A global overview of national regulations and standards for drinking-water quality

A global overview of national regulations and standards for drinking-water quality ii A global overview of national regulations and standards for drinking-water quality ISBN 978-92-4- 151376-0 © World Health Organization 2018 Some rights reserved. This work is available under the Creative Commons Attribution- NonCommercial-ShareAlike 3.0 IGO licence (CC BY-NC-SA 3.0 IGO; https://creativecommons.org/licenses/by-nc-sa/3.0/igo). Under the terms of this licence, you may copy, redistribute and adapt the work for non- commercial purposes, provided the work is appropriately cited, as indicated below. In any use of this work, there should be no suggestion that WHO endorses any specific organization, products or services. The use of the WHO logo is not permitted. If you adapt the work, then you must license your work under the same or equivalent Creative Commons licence. 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In no event shall WHO be liable for damages arising from its use. iii Contents Abbreviations and acronyms ........................................................................................... iv Role of the WHO Guidelines for Drinking-water Quality ............................................... 1 Inorganic parameters ........................................................................................................ 7 Organic parameters ......................................................................................................... 19 Parameters relating to acceptability, taste and odour and appearance ........................... 64 Radiological parameters ................................................................................................. 77 Microbiological parameters ............................................................................................ 80 Additional parameters..................................................................................................... 84 Conclusion ...................................................................................................................... 88 References and source documentation ........................................................................... 89 Box 1. Guidance levels, guideline values, and health-based values ................................. 1 Box 2. Provisional guideline values .................................................................................. 2 Figure 1: Countries and territories represented in the survey ........................................... 3 iv Abbreviations and acronyms Bq/l Becquerel per litre BSS Basic Safety Standards cfu colony forming units EU European Union Euratom European Atomic Energy Community GDWQ Guidelines for Drinking-water Quality GL Guidance level GV Guideline value HBV health-based value ICRP International Commission on Radiological Protection μg/l micrograms per litre mg/l milligrams per litre mSv/year milli Sieverts per year NTU Nephelometric turbidity unit PAHO Pan American Health Organization pCi/l pico Curie per litre RegNet WHO International Network of Drinking-water Regulators TCU true colour unit WHO World Health Organization WHOPES WHO Pesticide Evaluation Scheme 1 Role of the WHO Guidelines for Drinking-water Quality The Guidelines for Drinking-water Quality (GDWQ) are one of the longest-standing normative publications of the World Health Organization (WHO), with the first edition published in 1958. The GDWQ are an international reference point for the establishment of national or regional regulations and standards for water safety. They are addressed to water and health regulators, policy-makers and their advisors, mainly to assist them in the development of national standards. The GDWQ are also used by many others as a source of information on water quality and health and on effective management approaches. The GDWQ include an assessment of the health risks presented by the various microbial, chemical, radiological and physical contaminants that may be present in drinking-water. Where applicable, they derive maximum concentration guideline values for these hazardous constituents. Through a Framework for Safe Drinking Water, the GDWQ support the development of health-based targets, implementation of preventive risk management strategies (through water safety planning), and independent surveillance. Health-based water quality targets define drinking-water that does not represent any significant risk to health, generally over a lifetime of consumption. These numeric targets include ‘guidance levels’ (GL), ‘guideline values’ (GV) and 'health-based values' (HBV) for constituents in drinking-water or indicators of water quality (Box 1). Box 1. Guidance levels, guideline values, and health-based values The term ‘guidance levels’ is used for radiological parameters, while ‘guideline values’ or ‘health-based values’ is used for all other parameters. Generally, health-based values have been established for some chemicals in the GDWQ, rather than a formal guideline value, in order to provide guidance to Member States when there is reason for local concern. Establishing a formal guideline value for such substances may encourage Member States to incorporate a value into their national standards when this may be unnecessary. In the case of manganese, a health-based value was established rather than a guideline value as manganese is not of health concern at levels normally causing acceptability problems in drinking-water (e.g. staining of laundry). However, there are circumstances in which manganese can remain in solution at concentrations of health concern in some acidic or anaerobic waters, particularly groundwater. It may therefore be appropriate to incorporate manganese in national standards under these circumstances and to consider both aesthetic as well as health aspects when confirming the acceptability of drinking-water. 2 In addition, a number of provisional guideline values have been established based on the practical level of treatment performance or analytical achievability (Box 2). In these cases, the guideline value is higher than the calculated health-based value. Recognizing the benefits of a risk management approach, the GDWQ are not promoted as mandatory international standards, but as guidance that should be adapted to the specific circumstances, needs and resources of countries. Therefore, national or regional drinking-water quality regulations should only include a subset of the values included in the GDWQ and may have different parameter limits than what is specified in the GDWQ. Many countries use the GDWQ directly or indirectly in setting national drinking-water quality standards. To better understand the extent to which the GDWQ are used and reflected in these standards, a global review of various country regulations and policies was conducted. This report summarizes information from 104 countries and territories on values specified in national drinking-water quality standards for aesthetic, chemical, microbiological and radiological parameters. The aim of the report is to enable regulators and other key stakeholders to access and compare data when setting or revising national drinking-water quality standards, although comparison should be approached with caution. The report is not intended to provide guidance on selecting appropriate parameters and parameter limits for drinking-water quality standards. The separate publication, Developing Drinking-water Quality Regulations and Standards (WHO, in press) should be consulted for such guidance. Box 2. Provisional guideline values For several chemical parameters, the GDWQ suggest guidelines values which may be provisional for the following reasons:  A: provisional guideline value set at the achievable quantification level;  P: provisional guideline value because of uncertainties in the health database;  T: provisional guideline value set at the practical treatment level); and  D: provisional guideline value set considering possible health effects and the need to maintain adequate disinfection. Adequate disinfection of drinking-water remains paramount. For some chemicals, GVs are designated with a “C”. This indicates that the concentration of the substance at or below the guideline value may affect the appearance, taste or odour of the water, which may lead to consumer complaints. 3 Data sources and methods The data reviewed in the report were obtained from members of the WHO International Network of Drinking-water Regulators (RegNet)1, WHO regional and country office contacts, through internet searches or purchased from the relevant standards organizations. Data were collected for 104 countries and territories (Figure 1) up to 2015, and were reviewed and validated. The data validation entailed an online public review, as well as review by WHO regional and country office contacts, and RegNet members, who were asked to clarify inconsistencies and provide data updates wherever relevant. Figure 1: Countries and territories represented in the survey These countries and territories have a total population of approximately 6.5 billion people, representing approximately 89 % of the world population2. Countries that are members of the European Union (EU) are subject to the requirements of its Drinking-water Directive and European Atomic Energy Community (Euratom) which specifies radionuclide requirements. However, all these countries have their own regulations, some of which differ from the 1 Information about RegNet can be found at the following link: http://www.who.int/water_sanitation_health/water-quality/regulation/regnet/en/ 2 Based on mid-year population estimates for 2017: United Nations, Department of Economic and Social Affairs, Population Division (2017). World Population Prospects: The 2017 Revision. Wallchart 4 Directive with more stringent requirements or include additional parameters. In addition, it is understood that the following countries and territories use the standards specified in the GDWQ without currently publishing separate documentation listing regulatory parameters and values at the time that data for this report were collected: Burkina Faso, Kiribati, Kuwait, Mali, Nauru, Senegal, Solomon Islands, Tonga and Tuvalu. Countries and territories specify parameter values for drinking-water quality in a variety of formats; regulations, standards, specifications, laws, decrees, requirements and norms. For the purposes of this report these are all referred to as standards. The drinking-water quality standards specified by countries and territories for inorganic chemicals, organic chemicals, aesthetic and microbiological parameters were compared to the GV or HBV; and radiological parameters were compared to the GL of the fourth edition of the GDWQ (WHO, 2011)3. This report does not include detailed background information on the parameters, including derivation and adaptation of guideline values and appropriate risk management strategies; the report should be read in conjunction with the GDWQ to provide this information. The report also does not include the extent and effectiveness of compliance monitoring by national regulatory authorities against national standards, including information on how many samples are required or taken for each parameter; or whether drinking-water quality in each country and territory meets the values specified. Documentation and the report According to the documentation reviewed, the oldest specifications of values for drinking- water in current use date back to 1978. Fourteen countries and territories’ values, (42 including the members of the European Union (EU) through the European Drinking-water Directive) date to the 1990s. However, many EU Member States have implemented the Directive through more recent documentation but these have not been included in the survey because they differ little in requirements from the original Directive. The other 62 countries and territories have produced documentation in the year 2000 and later. As countries and territories often review their legislation and values, these findings are constantly subject to change. 3 The most recent edition of the GDWQ is the fourth edition, first addendum published in 2017. For the first addendum, risk assessments for the following parameters have been revised, resulting in updated guideline or health-based values: barium, bentazone, diquat and MCPA. As the first addendum was published after the cut-off date for the review and further, as countries have had little time to consider the first addendum in their national standards, an analysis against these updated values has not been included in this document. Information on the changes made in the first addendum to the fourth edition of the GDWQ can be found at the following link: http://www.who.int/water_sanitation_health/publications/gdwq4-1st-addendum/en/ 5 Thirty-seven countries and territories directly reference the GDWQ in their standards, although this number is likely to be higher because the full documentation was not available in all cases. Botswana and Pakistan list the WHO GV alongside their values. Although the GDWQ encourage countries and territories to set their own water-quality standards to ensure they are locally relevant in terms of parameters included, limits, etc., none of the documentation received includes a full explanation on why parameters are included and how countries and territories derived their values, including where they differ from the WHO GV. However, this is now becoming more readily available in separate documentation such as that produced by Health Canada. Others more generally reference WHO and other countries and territories’ values, such as those of the European Union, the United States of America, Nigeria and South Africa. Some countries and territories’ standards also reference the analytical method required. In some cases the names of the members of expert committees who drew up the values are listed. Some countries and territories include in their standards details of the likely origin of parameters and their associated risk. This may help the understanding of those who have to control and analyze drinking-water quality. Examples are Australia, the Dominican Republic, Fiji, India, New Zealand, Nigeria, Pakistan, the Philippines, South Africa, Uruguay and the USA. Other countries and territories may provide similar information in separate documentation or consider the information included in the GDWQ sufficient. In addition to setting values for specific parameters, many countries and territories’ documentation includes a general statement along the lines of: “water intended for human consumption should: not contain concentrations of compounds which could, either alone or in combination with other compounds, be harmful to human health; and not contain any micro- organisms and parasites in such a number that could be harmful to human health”. For the purposes of this report, all values for chemical parameters have been converted to mg/l. The values used in this report are the highest listed by countries and territories in their standards for normal (non-emergency or severe weather-affected) water supplies. Not all the values countries and territories have listed are mandatory; some are advisory, for guidance or occasionally described as operational. This applies particularly to the aesthetic and other parameters. The GDWQ suggest values with a wide margin of safety, and countries and territories are advised to adapt their drinking-water quality standards to local conditions and circumstances. 6 For clarity and convenience this report has adopted the terms “higher” or “above” for values greater than those specified in the GDWQ and “lower” or “below” for values less than those specified in the GDWQ. Countries and territories may have good reasons to specify a value more, or less stringent than WHO based on an overall risk-benefit strategy to protect public health, whereby scarce resources directed to provide greatest public health benefits. In addition, differences in the number of parameters specified by countries and territories are to be expected, according to the relevance of the parameters to the countries and territories concerned. A list of source documentation used in this survey is provided at the end of the report. 7 Inorganic parameters The 4th edition of the GDWQ includes GVs or HBVs for 24 inorganic parameters. All 104 countries and territories specify values for copper, lead and nitrate, and all but one specify values for manganese. The least specified inorganic parameters were: beryllium (12 out 104 countries); glyphosate (11); and uranium (17). All the median values equalled or were below the GV except for cadmium (GV 0.003 mg/l, median 0.005 mg/l). Antimony WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 76 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 13 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 62 Maximum value set 0.05 mg/l Minimum value set 0.003 mg/l Median value 0.005 mg/l The majority of countries and territories (62/76) set a value for antimony below the GV, with 50 countries and territories setting 0.005 mg/l. Arsenic WHO Guideline value 0.01 mg/l (provisional A, T) Number of countries and territories setting a regulatory / guideline value 102 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 22 Number of countries and territories setting the WHO Guideline 79 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.5 mg/l Minimum value set 0.007 mg/l Median value 0.01 mg/l 8 Arsenic is one of the parameters with a value set by most countries and territories (102/104). The majority of countries (79/102) specified the provisional GV; only one country set a value below the provisional GV. Barium WHO Guideline value 0.7 mg/l4 Number of countries and territories setting a regulatory / guideline value 52 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 11 Number of countries and territories setting the WHO Guideline 35 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 6 Maximum value set 2.0 mg/l Minimum value set 0.1 mg/l Median value 0.7 mg/l The majority (35/52) of those countries and territories setting a value for barium specified the GV. Beryllium WHO Guideline value None specified WHO Health-based value 0.012 mg/l Number of countries and territories setting a regulatory / guideline value 12 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Health-based value 1 Number of countries and territories setting the WHO Health-based value 0 Number of countries and territories setting a regulatory / guideline value less than WHO Health-based value 11 Maximum value set 0.06 mg/l Minimum value set 0.0002 mg/l Median value 0.004 mg/l Beryllium is one of the least specified parameters; with only 12 out of the 104 countries and territories surveyed setting a value. 4 The GV has been increased to 1.3 mg/l in the first addendum to the 4th edition of GDWQ (WHO, 2017), which is available here: http://apps.who.int/iris/bitstream/10665/254637/1/9789241549950-eng.pdf?ua=1 9 Boron WHO Guideline value 2.4 mg/l Number of countries and territories setting a regulatory / guideline value 73 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 1 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 70 Maximum value set 5 mg/l Minimum value set 0.2 mg/l Median value 1 mg/l No country set the revised GV for boron in the 4th edition of the GDWQ (WHO, 2011); most countries and territories had based their value on the previous provisional GV of 0.5 mg/l. Bromate WHO Guideline value 0.01 mg/l (provisional A,T) Number of countries and territories setting a regulatory / guideline value 60 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 8 Number of countries and territories setting the WHO Guideline 51 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.025 mg/l Minimum value set 0.005 mg/l Median value 0.01 mg/l Most countries and territories specified a value for bromate at or close to the provisional GV. 10 Cadmium WHO Guideline value 0.003 mg/l Number of countries and territories setting a regulatory / guideline value 101 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 59 Number of countries and territories setting the WHO Guideline 38 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 4 Maximum value set 0.05 mg/l Minimum value set 0.001 mg/l Median value 0.005 mg/l Cadmium is the inorganic parameter for which the most countries and territories specified a higher value than the GV, as demonstrated by the median value. Only four countries and territories specified a value below the GV. Chlorate WHO Guideline value 0.7 mg/l (provisional D) Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 10 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 3 Maximum value set 1.0 mg/l Minimum value set 0.05 mg/l Median value 0.7 mg/l Only 16 countries and territories set a value for chlorate. On these, 10 set the provisional GV of 0.7 mg/L. 11 Chlorine WHO Guideline value*(C) 5.0 mg/l (as free chlorine) Number of countries and territories setting a regulatory / guideline value 66 Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 13 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 53 Maximum value set 5.0 mg/l Minimum value set 0.1 mg/l Median value 0.9 mg/l *It is possible to reduce the concentration of chlorine effectively to zero (<0.1 mg/l) by reduction; however, it is normal practice to supply water with a chlorine dioxide residual of a few tenths of a milligram per litre to provide some protection against microbial regrowth during distribution. Chlorine is the inorganic parameter with the largest range between minimum and maximum. No country had a value above the GV. Thirty two countries and territories specified a level below 1 mg/l. Eleven countries and territories specified the GV. Some countries and territories set a range, specifying minimum and maximum levels. It was not always clear if the set value referred to free or total chlorine. Chlorite WHO Guideline value 0.7 mg/l (provisional D) Number of countries and territories setting a regulatory / guideline value 28 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 6 Number of countries and territories setting the WHO Guideline 12 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 10 Maximum value set 1.0 mg/l Minimum value set 0.05 mg/l Median value 0.7 mg/l Twenty eight countries and territories set a value for chlorite, and of these, 12 specified the GV. 12 Chromium (total) WHO Guideline value 0.05 mg/l (provisional P) Number of countries and territories setting a regulatory / guideline value 99 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 94 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.5 mg/l Minimum value set 0.04 mg/l Median value 0.05 mg/l Most countries and territories set a value for total chromium, and the great majority set the provisional GV. Copper WHO Guideline value* 2.0 mg/l Number of countries and territories setting a regulatory / guideline value 104 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 51 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 51 Maximum value set 3.0 mg/l Minimum value set 0.05 mg/l Median value 1.5 mg/l *The GDWQ also notes that copper causes aesthetic issues including staining of laundry at concentrations above 1 mg/l Copper is one of only three inorganic parameters with a value set by all the countries and territories in the survey. The majority specified the GV, or specified lower values. Only two countries set values above the GV. 13 Cyanide WHO Guideline value No value established in fourth edition, previously 0.07 mg/l* WHO Health-based value 0.5 mg/l (rounded value, for short-term exposure) Number of countries and territories setting a regulatory / guideline value 101 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than the WHO health-based value 11 Number of countries and territories setting the previous WHO health-based value 30 Number of countries and territories setting a regulatory / guideline value less than the previous WHO health-based value 60 Maximum value set 0.6 mg/l Minimum value set 0.01 mg/l Median value 0.05 mg/l *The GV was changed to a HBV in the 4th edition of the GDWQ. The majority of countries and territories (101/104) set a value for this parameter, and over half specified values below the GV. Fluoride WHO Guideline value 1.5 mg/l Number of countries and territories setting a regulatory / guideline value 102 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 8 Number of countries and territories setting the WHO Guideline 77 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 17 Maximum value set 4.0 mg/l Minimum value set 0.6 mg/l Median value 1.5 mg/l All but two countries specified a value for this parameter, and the majority set the GV. Many specified a lower value for higher water temperatures. In some cases where a low value was set, a higher value was allowed under certain circumstances. 14 Glyphosate WHO Guideline value None specified WHO health-based value 0.9 mg/l Number of countries and territories setting a regulatory / guideline value 11 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Health-based value 1 Number of countries and territories setting the WHO Health-based value 0 Number of countries and territories setting a regulatory / guideline value less than WHO Health-based value 10 Maximum value set 1 mg/l Minimum value set 0.01 mg/l Median value 0.7 mg/l The GDWQ link together glyphosate and its major metabolite aminomethylphosphonic acid (AMPA). Because of their low toxicity, the health-based value derived for AMPA alone or in combination with glyphosate is orders of magnitude higher than concentrations of glyphosate or AMPA normally found in drinking-water. Under usual conditions, therefore, the presence of glyphosate and AMPA in drinking-water does not represent a hazard to human health. For this reason, the establishment of a formal guideline value for glyphosate and AMPA is not deemed necessary. Glyphosate is one of the least specified parameters; with only 11 out of the 104 countries and territories setting a value. No country or territory specified a value for AMPA. Lead WHO Guideline value 0.01 mg/l (provisional; A, T) Number of countries and territories setting a regulatory / guideline value 104 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 19 Number of countries and territories setting the WHO Guideline 84 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.1 mg/l Minimum value set 0.005 mg/l Median value 0.01 mg/l Lead is one of only three inorganic parameters with a value specified by all countries and territories in this survey. The majority set the GV, while some countries and territories allowed 15 time for the 0.01 mg/l standard to apply. Of the countries and territories that set a value above the GDWQ, most specified 0.05 mg/l. Manganese WHO Guideline value No value established in the fourth edition, previously 0.4 mg/l WHO Health-based value (4th edition)* 0.4 mg/l Number of countries and territories setting a regulatory / guideline value 103 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than the previous WHO Guideline 19 Number of countries and territories setting the previous WHO Guideline 11 Number of countries and territories setting a regulatory / guideline value less than the previous WHO Guideline 73 Maximum value set 0.5 mg/l Minimum value set 0.05 mg/l Median value 0.1 mg/l *The GV was changed to a HBV in the 4th edition of the GDWQ, recognizing that manganese is not of health concern at levels normally causing acceptability problems in drinking-water. Manganese can cause aesthetic issues, including taste impacts and staining of laundry at concentrations above 0.1 mg/l. However, there are circumstances in which manganese can remain in solution at concentrations of health concern in some acidic or anaerobic waters, particularly groundwaters. Therefore, aesthetic as well as health aspects should be considered in the establishment of standards and confirming the acceptability of drinking-water. All countries and territories in the survey set a value for manganese with the exception of one. The majority set a value below the previous GV. Some countries and territories listed the parameter as aesthetic, some as inorganic, and some as both. Mercury WHO Guideline value 0.006 mg/l Number of countries and territories setting a regulatory / guideline value 100 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 4 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 95 Maximum value set 0.007 mg/l Minimum value set 0.0005 mg/l Median value 0.001 mg/l 16 The majority of countries and territories (100/104) set a value for this parameter. Only four countries specified the GV; the most specified values below the GV. Molybdenum WHO Guideline value 0.07 mg/l Number of countries and territories setting a regulatory / guideline value 26 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 22 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.25 mg/l Minimum value set 0.05 mg/l Median value 0.07 mg/l The majority (22/26) of the countries and territories setting a value for molybdenum specified the GV. Nickel WHO Guideline value 0.07 mg/l Number of countries and territories setting a regulatory / guideline value 82 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 7 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 72 Maximum value set 0.1 mg/l Minimum value set 0.01 mg/l Median value 0.02 mg/l Most countries and territories specifying a value for nickel set it below the GV, at 0.02 mg/l. 17 Nitrate WHO Guideline value 50 mg/l* (as NO3-) Number of countries and territories setting a regulatory / guideline value 104 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 69 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 33 Maximum value set 75 mg/l (as NO3-) Minimum value set 40 mg/l (as NO3-) Median value 50 mg/l (as NO3-) *The GDWQ also include a value for combined nitrate plus nitrite as: The sum of the ratios of the concentrations as reported or detected in the sample of each to its guideline value should not exceed 1. Nitrate is one of only three inorganic parameters with a value set by all countries and territories in the survey. Many quoted their value as 10 mg/l (as N) which has been converted to 45 mg/l (as NO3 -) for the purposes of this report but counted as being at the GV. Several countries and territories including the European Union countries included a formula that reduces the nitrate value as the nitrite level increases. Nitrite WHO Guideline value 3 mg/l* (as NO2-) Number of countries and territories setting a regulatory / guideline value 96 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 39 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 55 Maximum value set 3.3 mg/l (as NO2-) Minimum value set 0.003 mg/l (as NO2-) Median value 0.5 mg/l (as NO2-) Median value 50 mg/l (as NO3-) *The GDWQ also include a value for combined nitrate plus nitrite as: The sum of the ratios of the concentrations as reported or detected in the sample of each to its guideline value should not exceed 1. Many countries and territories’ values for nitrite have been based on older WHO guidance. Only two countries had values above the revised GV. Thirty-nine countries and territories specified the revised GV (or its equivalent as mg N/l). Several countries and territories 18 including the European Union countries included a formula that reduces the nitrate value as the nitrite level increases. Selenium WHO Guideline value 0.04 mg/l (provisional, P) Number of countries and territories setting a regulatory / guideline value 96 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 1 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 93 Maximum value set 0.05 mg/l Minimum value set 0.007 mg/l Median value 0.01 mg/l Only one country specified the new provisional GV of 0.04 mg/l; almost all others specified the previous value of 0.01 mg/l. Uranium WHO Guideline value 0.03 mg/l (provisional P) Number of countries and territories setting a regulatory / guideline value 17 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 17 Maximum value set 0.1 mg/l Minimum value set 0.002 mg/l Median value 0.015 mg/l Uranium is one of the least specified parameters; with only 17 out of the 104 countries and territories setting a value. The majority specified a value based on the previous GV, with no country specifying the latest. 19 Organic parameters The 4th edition of the GDWQ includes GVs or HBVs for 89 organic parameters. The most specified organic parameters are: aldrin and dieldrin (71 out of 104 countries and territories); benzene (77); tetrachloroethene (71); and 1,2 dichloroethane (67). Among the least specified values are: 2-phenylphenol (1); fenitrothion (2); nitrobenzene (3); and N-nitrosodimethylamine (NDMA, 3). No country or territory specified a value for cyanuric acid, sodium dichloroisocyanurate or hydroxyatrazine. Seven countries and territories did not specify values for any inorganic parameters, while some included notes with general requirements for low levels of pesticides. For the organic parameters that had specifications, all but four had median values equal to or below the GV. The exceptions were: cyanazine (GV 0.0006 mg/l, median 0.0007 mg/l), but only specified by five countries and territories; dibromoacetonitrile (GV 0.07 mg/l, median 0.0775), specified by 16 countries and territories; dichloroacetonitrile (GV 0.02 mg/l, median 0.06 mg/l), specified by 17 countries and territories; and vinyl chloride (GV 0.0003 mg/l, median 0.0005 mg/l), specified by 60 countries and territories. Forty-six countries and territories do not specify values for most individual pesticides other than aldrin and dieldrin, heptachlor and heptachlor epoxide. Instead, they include a blanket statement that the value for all individual pesticides is 0.0001 mg/l, and for total pesticides 0.0005 mg/l (where “total pesticides” is defined as the sum of all individual pesticides detected and quantified in the monitoring procedure), or similar requirement. Where a country or territory does not specify a value for an individual parameter in its standards, it is not included in the tables below. Acrylamide WHO Guideline value 0.0005 mg/l Number of countries and territories setting a regulatory / guideline value 56 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 20 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 36 Maximum value set 0.0005 mg/l Minimum value set 0.0001 mg/l Median value 0.0001 mg/l 20 Almost half of the countries and territories (56/104) set a value for acrylamide. No country set a value greater than the GV; the majority set 0.0001 mg/l. Alachlor WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 24 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 19 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 4 Maximum value set 0.15 mg/l Minimum value set 0.002 mg/l Median value 0.02 mg/l Most countries and territories (19/24) set the GV; and only one set a higher value. Aldicarb WHO Guideline value 0.01 mg/l Number of countries and territories setting a regulatory / guideline value 22 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 17 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 5 Maximum value set 0.01 mg/l Minimum value set 0.003 mg/l Median value 0.01 mg/l Only five out of 22 countries and territories set values that differed from the GV. 21 Aldrin and Dieldrin WHO Guideline value 0.00003 mg/l Number of countries and territories setting a regulatory / guideline value 71 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 6 Number of countries and territories setting the WHO Guideline 62 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 3 Maximum value set 0.001 mg/l Minimum value set 0.00001 mg/l (0) Median value 0.00003 mg/l Most countries and territories (62/71) specified the GV, and only three set values that were lower. Atrazine and its chloro-s-triazine metabolites WHO Guideline value 0.1 mg/l Number of countries and territories setting a regulatory / guideline value 28 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 27 Maximum value set 0.5 mg/l Minimum value set 0.0015 mg/l Median value 0.002 mg/l There was wide deviation from the GV in the values set for this parameter. Only one country set a value above the GV, all the other countries and territories were well below. 22 Bentazone WHO Guideline value None specified WHO health-based value 0.3 mg/l5 Number of countries and territories setting a regulatory / guideline value 11 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Health-based value 2 Number of countries and territories setting the WHO Health-based value 4 Number of countries and territories setting a regulatory / guideline value less than WHO Health-based value 5 Maximum value set 0.4 mg/l Minimum value set 0.03 mg/l Median value 0.03 mg/l Only 11 countries and territories set a value for bentazone, and the majority set below the HBV of 0.3 mg/L specified in the 4th edition of the GDWQ (WHO, 2011). Benzene WHO Guideline value 0.01 mg/l Number of countries and territories setting a regulatory / guideline value 77 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 31 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 45 Maximum value set 0.03 mg/l Minimum value set 0.001 mg/l Median value 0.005 mg/l Benzene is the most specified organic parameter among the 104 countries and territories surveyed. The majority specified values below the GV of 0.01 mg/L, and only one country specified a higher value. 5 The HBV has been increased to 0.5 mg/l in the first addendum to the 4th edition of GDWQ (WHO, 2017), which is available here: http://apps.who.int/iris/bitstream/10665/254637/1/9789241549950-eng.pdf?ua=1 23 Benzo[a]pyrene WHO Guideline value 0.0007 mg/l Number of countries and territories setting a regulatory / guideline value 65 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 15 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 50 Maximum value set 0.0007 mg/l Minimum value set 0.000005 mg/l Median value 0.00001 mg/l Where countries and territories also had a value for polynuclear aromatic hydrocarbons (PAH; see additional parameters), this parameter was usually quoted separately. The majority of countries and territories set a value below the GV, and no country set a value higher than the GV. Bromodichloromethane WHO Guideline value 0.06 mg/l* Number of countries and territories setting a regulatory / guideline value 29 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 22 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 7 Maximum value set 0.06 mg/l Minimum value set 0.015 mg/l Median value 0.06 mg/l *See total trihalomethanes (THMs) for information on how to account for additive toxicity with other individual THM compounds Of the 29 countries and territories specifying a value for this parameter, the majority (22) specified the GV. Some countries and territories which did not specify a value for this parameter included it in their value for total trihalomethanes. 24 Bromoform WHO Guideline value 0.1 mg/l* Number of countries and territories setting a regulatory / guideline value 23 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 21 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.1 mg/l Minimum value set 0.075mg/l Median value 0.1 mg/l *See total trihalomethanes (THMs) for information on how to account for additive toxicity with other individual THM compounds All but two of the countries and territories specifying a value for this parameter used the GV. Some countries and territories which did not specify a value for this parameter included it in their value for total trihalomethanes. Carbofuran WHO Guideline value 0.007 mg/l Number of countries and territories setting a regulatory / guideline value 26 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 7 Number of countries and territories setting the WHO Guideline 10 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 9 Maximum value set 0.09 mg/l Minimum value set 0.0035 mg/l Median value 0.007 mg/l Twenty-six countries and territories specified a value for carbofuran, with the majority (16) setting values greater or less than the GV. 25 Carbon tetrachloride WHO Guideline value 0.004 mg/l Number of countries and territories setting a regulatory / guideline value 34 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 8 Number of countries and territories setting the WHO Guideline 10 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 16 Maximum value set 0.005 mg/l Minimum value set 0.0013 mg/l Median value 0.004 mg/l Twenty-four of the 34 countries and territories specifying a value for this parameter differed from the GV. Eight countries and territories specified 0.005 mg/l. Chloral hydrate (trichloracetaldehyde) WHO Health-based value 0.1 mg/l (rounded figure) Number of countries and territories setting a regulatory / guideline value 11 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO health-based value 0 Number of countries and territories setting the WHO health-based value 2 Number of countries and territories setting a regulatory / guideline value less than WHO health-based value 9 Maximum value set 0.1 mg/l Minimum value set 0.01 mg/l Median value 0.01 mg/l Only 11 countries and territories specified a value for chloral hydrate, and nine of these set values below the HBV. 26 Chlordane WHO Guideline value 0.0002 mg/l Number of countries and territories setting a regulatory / guideline value 33 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 9 Number of countries and territories setting the WHO Guideline 23 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.003 mg/l Minimum value set 0.00015 mg/l Median value 0.0002 mg/l The majority of countries and territories specifying a value for chlordane set the GV (23/33), and only one specified a lower value. Chloroform WHO Guideline value 0.3 mg/l* Number of countries and territories setting a regulatory / guideline value 36 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 6 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 29 Maximum value set 0.4 mg/l Minimum value set 0.03 mg/l Median value 0.2 mg/l *See total trihalomethanes (THMs) for information on how to account for additive toxicity with other individual THM compounds The majority of countries and territories specifying a value for this parameter set a value below the GV, most specifying 0.2 mg/l. Some countries and territories did not specify a value for this parameter but included it in their value for total trihalomethanes. 27 Chlorotoluron WHO Guideline value 0.03 mg/l Number of countries and territories setting a regulatory / guideline value 12 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 10 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.04 mg/l Minimum value set 0.02 mg/l Median value 0.03 mg/l The majority of countries and territories specifying a value for chlorotoluron set the GV (10/12). Chlorpyrifos WHO Guideline value 0.03 mg/l Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 12 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.09 mg/l Minimum value set 0.01 mg/l Median value 0.03 mg/l The majority of countries and territories specifying a value for this parameter set the GV (12/16). 28 Cyanazine WHO Guideline value 0.0006 mg/l Number of countries and territories setting a regulatory / guideline value 5 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 2 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.01 mg/l Minimum value set 0.0006 mg/l Median value 0.0007 mg/l Only five countries and territories specified a value for cyanazine, and none set a value below the GV. Cyanogen Chloride WHO Guideline value No value specified in fourth edition, previously 0.07 mg/l WHO Health-based value 0.6 mg/l (rounded value) Number of countries and territories setting a regulatory / guideline value 13 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than previous WHO Guideline 0 Number of countries and territories setting the previous WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than previous WHO Guideline 13 Maximum value set 0.07 mg/l Minimum value set 0.05 mg/l Median value 0.07 mg/l The 4th edition of the GDWQ specifies a HBV of 0.6 mg/l for cyanogen chloride, a change from the GV of 0.07 mg/l previously specified in the 3rd edition. All the thirteen countries and territories setting values for this parameter set values lower than the HBV. All countries and territories specified the former GV (0.07 mg/l) except one (0.005 mg/l). 29 Cyanuric Acid WHO Guideline value 40 mg/l Number of countries and territories setting a regulatory / guideline value 0 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 No country in the survey set a value for this parameter. 2,4-D (2,4-Dichlorophenoxyacetic Acid) WHO Guideline value 0.03 mg/l Number of countries and territories setting a regulatory / guideline value 42 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 9 Number of countries and territories setting the WHO Guideline 31 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.1 mg/l Minimum value set 0.01 mg/l Median value 0.03 mg/l The majority of countries and territories setting a value for this parameter designated the GV; only two set values less than the GV. 2,4-DB (2,4-Dichlorophenoxybutyric Acid) WHO Guideline value 0.09 mg/l Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 4 Number of countries and territories setting the WHO Guideline 11 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.1 mg/l Minimum value set 0.067 mg/l Median value 0.09 mg/l 30 Only 16 countries and territories designated a value for this parameter, with most setting the GV. Dichlorodiphenyltrichloroethane (DDT) and metabolites WHO Guideline value 0.001 mg/l Number of countries and territories setting a regulatory / guideline value 42 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 18 Number of countries and territories setting the WHO Guideline 24 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.05 mg/l Minimum value set 0.001 mg/l Median value 0.001 mg/l Forty-two countries and territories specified a value for DDT, with over half (24/42) setting the GV. Di(2-ethylhexyl)phthalate WHO Guideline value 0.008 mg/l Number of countries and territories setting a regulatory / guideline value 11 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 7 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 3 Maximum value set 0.009 mg/l Minimum value set 0.002 mg/l Median value 0.008 mg/l Eleven countries and territories designated a value for this parameter, and only one set a value greater than the GV. 31 Dibromoacetylnitrile WHO Guideline value 0.07 mg/l Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 9 Number of countries and territories setting the WHO Guideline 6 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.1 mg/l Minimum value set 0.01 mg/l Median value 0.0775 mg/l Only 16 countries and territories designated a value for this parameter, and only one set a value less than the GV. Dibromochloromethane WHO Guideline value 0.1 mg/l* Number of countries and territories setting a regulatory / guideline value 29 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 23 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 5 Maximum value set 0.15 mg/l Minimum value set 0.01 mg/l Median value 0.1 mg/l *See total trihalomethanes (THMs) for information on how to account for additive toxicity with other individual THM compounds Among the twenty-nine countries and territories designating a value for dibromochloromethane, the majority specified the GV, and only one set a greater value. 32 1,2-Dibromo-3-chloropropane WHO Guideline value 0.001 mg/l Number of countries and territories setting a regulatory / guideline value 21 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 16 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 3 Maximum value set 0.007 mg/l Minimum value set 0.0002 mg/l Median value 0.001 mg/l Only five out of 21 countries and territories set values that differed from the GV for 1,2- Dibromo-3-chloropropane. 1,2-Dibromoethane WHO Guideline value 0.0004 mg/l Number of countries and territories setting a regulatory / guideline value 8 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 7 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.0004 mg/l Minimum value set 0.00001 mg/l Median value 0.0004 mg/l Only eight countries and territories specified a value for this parameter, and the majority set the GV. 33 Dichloroacetic acid WHO Guideline value 0.05 mg/l (provisional, D) Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 14 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.05 mg/l Minimum value set 0.02 mg/l Median value 0.05 mg/l Of the 16 countries and territories specifying a value for dichloroacetic acid, only two did not specify the provisional GV. Dichloroacetonitrile WHO Guideline value 0.02 mg/l (provisional, P) Number of countries and territories setting a regulatory / guideline value 17 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 9 Number of countries and territories setting the WHO Guideline 7 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.09 mg/l Minimum value set 0.01 mg/l Median value 0.06 mg/l Seventeen countries and territories specified a value for dichloroacetonitrile, and of these, almost half (9/17) set values above the provisional GV. 34 1,2-Dichlorobenzene WHO Guideline value 1 mg/l (C)* Number of countries and territories setting a regulatory / guideline value 26 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 15 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 9 Maximum value set 1.5 mg/l Minimum value set 0.0005 mg/l Median value 1 mg/l *Concentrations at or below the health-based guideline value may affect the appearance, taste or odour of the water, leading to consumer complaints There was wide variation in values specified for this parameter according to whether countries and territories followed the WHO health-based GV or a value based on taste and odour thresholds. Some specified values for both. 1,4-Dichlorobenzene WHO Guideline value 0.3 mg/l (C)* Number of countries and territories setting a regulatory / guideline value 25 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 15 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 9 Maximum value set 0.4 mg/l Minimum value set 0.0004 mg/l Median value 0.3 mg/l *Concentrations at or below the health-based guideline value may affect the appearance, taste or odour of the water, leading to consumer complaints As with 1,2- Dichlorobenzene, countries and territories also specified health-based GVs or values based on taste and odour thresholds, and some specified values for both. 35 1,2-Dichloroethane WHO Guideline value 0.03 mg/l Number of countries and territories setting a regulatory / guideline value 67 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 18 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 47 Maximum value set 0.05 mg/l Minimum value set 0.003 mg/l Median value 0.003 mg/l Of the 67 countries and territories specifying a value for this parameter, 33specified the lowest value of 0.003 mg/l, and only 2 specified values greater than the GV. 1,1-Dichloroethene (Vinylidene chloride) WHO Guideline value No value established in the 4th edition, previously 0.03 mg/l WHO Health-based value 0.140 mg/l Number of countries and territories setting a regulatory / guideline value 30 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than the previous WHO Guideline 0 Number of countries and territories setting the previous WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than the previous WHO Guideline 30 Maximum value set 0.1 mg/l Minimum value set 0.0003 mg/l Median value 0.03 mg/l The 4th edition of the GDWQ specify a HBV of 140 μg/l (0.140 mg/l) for 1,1-dichloroethene, a change from the GV of 0.03 mg/l previously specified in the 3rd edition. All the thirty countries and territories setting values for this parameter set values less than the HBV. 36 1,2-Dichloroethene WHO Guideline value 0.05 mg/l Number of countries and territories setting a regulatory / guideline value 23 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 4 Number of countries and territories setting the WHO Guideline 17 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.1 mg/l Minimum value set 0.035 mg/l Median value 0.05 mg/l Of the 23 countries and territories setting a value for this parameter, the majority (17/23) did not differ from the GV. Dichloromethane WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 28 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 21 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 5 Maximum value set 0.05 mg/l Minimum value set 0.003 mg/l Median value 0.02 mg/l Of the 28 countries and territories setting a value for this parameter, the majority (17/23) did not differ from the GV. 37 1,2-Dichloropropane WHO Guideline value 0.04 mg/l (provisional P) Number of countries and territories setting a regulatory / guideline value 20 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 6 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 13 Maximum value set 0.05 mg/l Minimum value set 0.005 mg/l Median value 0.02 mg/l Twenty countries and territories set a value for this parameter, and the majority (13/20) specified values less than the GV. 1,3-Dichloropropene WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 14 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.1 mg/l Minimum value set 0.015 mg/l Median value 0.02 mg/l The majority of countries and territories (14/16) setting a value for 1,3-Dichloropropene specified the GV. 38 Dichlorprop WHO Guideline value 0.1 mg/l Number of countries and territories setting a regulatory / guideline value 19 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 18 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.1 mg/l Minimum value set 0.075 mg/l Median value 0.1 mg/l None of the 19 countries and territories specifying a value for dichlorprop set a value above the GV. Di(2-ethylhexyl)phthalate WHO Guideline value 0.008 mg/l Number of countries and territories setting a regulatory / guideline value 17 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 10 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 4 Maximum value set 0.1 mg/l Minimum value set 0.001 mg/l Median value 0.008 mg/l The majority of countries and territories (10/17) specified the GV for di(2- ethylhexyl)phthalateJapan of 0.1 mg/l. 39 Dimethoate WHO Guideline value 0.006 mg/l Number of countries and territories setting a regulatory / guideline value 12 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 9 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.08 mg/l Minimum value set 0.006 mg/l Median value 0.006 mg/l Only three countries out of 12 specified values above the GV for dimethoate, and none specified values below. 1,4-Dioxane WHO Guideline value 0.05 mg/l Number of countries and territories setting a regulatory / guideline value 5 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 5 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.05 mg/l Minimum value set 0.05 mg/l Median value 0.05 mg/l All five countries specifying a value for this parameter set the GV. 40 Diquat WHO Guideline value None WHO Health-based value 0.006 mg/l6 Number of countries and territories setting a regulatory / guideline value 7 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 7 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.07 mg/l Minimum value set 0.007 mg/l Median value 0.02 mg/l All seven countries and territories that specified a value for diquat set values above the HBV of 0.006 mg/L. Edetec Acid (EDTA) WHO Guideline value 0.6 mg/l Number of countries and territories setting a regulatory / guideline value 18 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 8 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 9 Maximum value set 0.7 mg/l Minimum value set 0.15 mg/l Median value 0.425 mg/l Of the eighteen countries and territories specifying a value for EDTA, only one set a value above the GV. 6 The HBV has been increased to 0.03 mg/l in the first addendum to the 4th edition of GDWQ (WHO, 2017), which is available here: http://apps.who.int/iris/bitstream/10665/254637/1/9789241549950-eng.pdf?ua=1 41 Endrin WHO Guideline value 0.0006 mg/l Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 4 Number of countries and territories setting the WHO Guideline 9 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 3 Maximum value set 0.002 mg/l Minimum value set 0.0001 mg/l Median value 0.0006 mg/l The majority (9/16) of countries and territories setting a value for endrin specified the GV. Endosulfan WHO Guideline value None WHO Health-based value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 9 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 3 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 4 Maximum value set 0.03 mg/l Minimum value set 0.00035 mg/l Median value 0.02 mg/l Nine countries and territories set a value for endosulfan. 42 Epichlorohydrin WHO Guideline value 0.0004 mg/l Number of countries and territories setting a regulatory / guideline value 54 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 16 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 35 Maximum value set 0.0005 mg/l Minimum value set 0.0001 mg/l Median value 0.0001 mg/l Over half of the countries and territories in the survey specified a value for this parameter, with the majority (35/54) setting a value below the GV of 0.0004 mg/L. Thirty-two countries and territories specified 0.0001 mg/l; and one country specified 0.0002 mg/l as a treatment standard only where epichlorohydrin is used in treatment. Ethylbenzene WHO Guideline value 0.3 mg/l (C)* Number of countries and territories setting a regulatory / guideline value 27 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 21 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 3 Maximum value set 0.7 mg/l Minimum value set 0.0024 mg/l Median value 0.3 mg/l *Concentrations at or below the health-based guideline value may affect the appearance, taste or odour of the water, leading to consumer complaints The majority (21/27) of countries and territories specified the GV for ethylbenzene. 43 Fenitrothion WHO Guideline value None WHO Health-based value 0.008 mg/l Number of countries and territories setting a regulatory / guideline value 2 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.04 mg/l Minimum value set 0.007 mg/l Median value 0.0235 mg/l Fenitrithion is one of the least specified organic parameters, with only two countries specifying a value. Fenoprop WHO Guideline value 0.009 mg/l Number of countries and territories setting a regulatory / guideline value 14 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 11 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.01 mg/l Minimum value set 0.006 mg/l Median value 0.009 mg/l Of the 14 countries and territories specifying a value for fenoprop, there is little variation from the GV of 0.009 mg/L 44 Heptachlor and Heptachlor Epoxide WHO Guideline value None specified WHO Health-based value 0.00003 mg/l Number of countries and territories setting a regulatory / guideline value 21 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO health-based value 5 Number of countries and territories setting the WHO health-based value 16 Number of countries and territories setting a regulatory / guideline value less than WHO health-based value 0 Maximum value set 0.0002 mg/l Minimum value set 0.00003 mg/l Median value 0.00003 mg/l Of the 21 countries and territories specifying a value for heptachlor and heptachlor epoxide, none set a value less than the HBV. Hexachlorobenzene WHO Guideline value None specified WHO Health-based value 0.001 mg/l Number of countries and territories setting a regulatory / guideline value 22 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO health-based value 0 Number of countries and territories setting the WHO health-based value 16 Number of countries and territories setting a regulatory / guideline value less than WHO health-based value 6 Maximum value set 0.001 mg/l Minimum value set 0.00001 mg/l Median value 0.001 mg/l The majority of countries and territories (16/22) specifying a value for hexachlorobenzene set the HBV, and none set values greater. 45 Hexachlorobutadiene WHO Guideline value 0.0006 mg/l Number of countries and territories setting a regulatory / guideline value 19 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 12 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 5 Maximum value set 0.0007 mg/l Minimum value set 0.0004 mg/l Median value 0.0006 mg/l The majority of countries and territories (12/19 ) specifying a value for hexachlorobutadiene set the GV. Hydroxyatrazine WHO Guideline value 0.2 mg/l Number of countries and territories setting a regulatory / guideline value 0 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 None of countries and territories in the survey specified a value for this parameter. 46 Isoproturon WHO Guideline value 0.009 mg/l Number of countries and territories setting a regulatory / guideline value 19 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 17 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.01 mg/l Minimum value set 0.007 mg/l Median value 0.009 mg/l There was little variation from the GV in the values specified for isoproturon, with only 2/19 countries and territories specifying the GV. Lindane WHO Guideline value 0.002 mg/l Number of countries and territories setting a regulatory / guideline value 44 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 7 Number of countries and territories setting the WHO Guideline 32 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 5 Maximum value set 0.01 mg/l Minimum value set GV 0.0002 mg/l Median value 0.002 mg/l Of the 44 countries and territories specifying a value for lindane, the majority set the GV. 47 MCPA (4-(2-Methyl-4-chlorophenoxy) acetic acid) WHO Guideline value 0.002 mg/l7 Number of countries and territories setting a regulatory / guideline value 22 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 19 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.1 mg/l Minimum value set 0.002 mg/l Median value 0.002 mg/l All countries and territories specifying a value for MCPA set the GV, with the exception of three that set values greater values. Mecoprop WHO Guideline value 0.01 mg/l Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 14 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.01 mg/l Minimum value set 0.001 mg/l Median value 0.01 mg/l Mecoprop was specified by 16 countries and territories, and only two did not specify the GV. 7 The guideline value has changed to 0.7 mg/l in the first addendum to the 4th edition of GDWQ, which can be found here: http://www.who.int/water_sanitation_health/publications/drinking-water-quality-guidelines-4- including-1st-addendum/en/ 48 Methoxychlor WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 38 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 8 Number of countries and territories setting the WHO Guideline 29 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.9 mg/l Minimum value set 0.015 mg/l Median value 0.02 mg/l Most countries and territories (29/38) specified the GV but there was considerable variation in the nine other values for this parameter. Methyl parathion WHO Guideline value None WHO Health-based value 0.009 mg/l Number of countries and territories setting a regulatory / guideline value 8 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 1 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 4 Maximum value set 0.1 mg/l Minimum value set 0.0003 mg/l Median value 0.008 mg/l Eight countries and territories set a value for methyl parathion, and only one of them specified the GV. 49 Metolachlor WHO Guideline value 0.01 mg/l Number of countries and territories setting a regulatory / guideline value 21 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 18 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.3 mg/l Minimum value set 0.007 mg/l Median value 0.01 mg/l All 21 of the countries and territories specifying a value for metolachlor specified the GV, with the exception of three countries. Microcystin-LR WHO Guideline value 0.001 mg/l (provisional, P) Number of countries and territories setting a regulatory / guideline value 14 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 12 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.0015 mg/l Minimum value set 0.001 mg/l Median value 0.001 mg/l Microcystin-LR was specified by 14 countries and territories, and of these, only two did not specify the provisional GV of 0.001 mg/L. 50 Molinate WHO Guideline value 0.006 mg/l Number of countries and territories setting a regulatory / guideline value 20 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 17 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.007 mg/l Minimum value set 0.004 mg/l Median value 0.006 mg/l Of the 20 countries and territories specifying a value for molinate, only three did not specify the GV. Monochloramine WHO Guideline value 3 mg/l Number of countries and territories setting a regulatory / guideline value 19 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 15 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 4 mg/l Minimum value set 2 mg/l Median value 3 mg/l Of the 19 countries and territories specifying a value for this parameter only four did not specify the GV. One country specified 3 mg/l post-treatment, but 0.05 mg/l in distribution. 51 Monochloroacetic Acid (Monochloroacetate) WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 7 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 6 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.2 mg/l Minimum value set 0.02 mg/l Median value 0.02 mg/l Only seven countries and territories specified a value for monochloroacetate, and almost all specified the GV. Nitrilotriacetic Acid WHO Guideline value 0.2 mg/l Number of countries and territories setting a regulatory / guideline value 18 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 16 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.4 mg/l Minimum value set 0.15 mg/l Median value 0.2 mg/l Of the 18 countries and territories specifying a value for this parameter only two did not specify the GV. 52 Nitrobenzene WHO Guideline value None WHO Health-based value 0.03 mg/l (short term) 0.008-0.063 mg/l (long term exposure, depending on end-point and approach used) Number of countries and territories setting a regulatory / guideline value 3 Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.2 mg/l Minimum value set 0.004 mg/l Median value 0.102 mg/l The GDWQ derive two HBVs for nitrobenzene; one for short- and the other for long-term exposure, based on the limited available information. Only three countries specified a value for this parameter. N-Nitrosodimethylamine (NDMA) WHO Guideline value 0.0001 mg/l Number of countries and territories setting a regulatory / guideline value 3 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 1 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.0001 mg/l Minimum value set 0.000012 mg/l Median value 0.00004 mg/l NDMA is among the least specified organic parameters, with only three countries and territories specifying a value. 53 Parathion WHO Guideline value None WHO Health-based value 0.01 mg/l Number of countries and territories setting a regulatory / guideline value 7 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 5 Number of countries and territories setting the WHO Guideline 1 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.05 mg/l Minimum value set 0.003 mg/l Median value 0.02 mg/l The majority of countries and territories setting values for this parameter (5/7) specified values above the HBV of 0.01 mg/L. Pendimethalin WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 20 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 18 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.4 mg/l Minimum value set 0.015 mg/l Median value 0.02 mg/l Of the 20 countries and territories specifying a value for pendimethalin, only two did not specify the GV. 54 Pentachlorophenol (PCP) WHO Guideline value 0.009 mg/l Number of countries and territories setting a regulatory / guideline value 35 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 5 Number of countries and territories setting the WHO Guideline 23 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 7 Maximum value set 0.06 mg/l Minimum value set 0.0001 mg/l Median value 0.009 mg/l The majority of countries and territories specifying values for PCP specified the GV. Permethrin WHO Guideline value No value established in fourth edition, previously 0.3 mg/l WHO Health-based value* 0.3mg/l Number of countries and territories setting a regulatory / guideline value 17 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than the previous WHO Guideline 0 Number of countries and territories setting the previous WHO Guideline 3 Number of countries and territories setting a regulatory / guideline value less than the previous WHO Guideline 14 Maximum value set 0.3 mg/l Minimum value set 0.02 mg/l Median value 0.02 mg/l *The GV was changed to a HBV in the 4th edition of the GDWQ, recognizing that it is not recommended for direct addition to drinking-water as part of WHO’s policy to exclude the use of any pyrethroids for larviciding of mosquito vectors of human disease Permethrin was specified by 17 countries and territories. The majority specified values less than the HBV of 0.3 mg/L, with 13 countries and territories specifying 0.02 mg/l. 55 2-Phenylphenol and its sodium salt WHO Guideline value None WHO Health-based value 1 mg/l Number of countries and territories setting a regulatory / guideline value 1 Number of countries and territories setting a regulatory / guideline value greater than the previous WHO Guideline 1 Number of countries and territories setting the previous WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than the previous WHO Guideline 0 Maximum value set 1.4 mg/l Minimum value set 1.4 mg/l Median value 1.4 mg/l 2-Phenylphenol is among the least specified organic parameters; only one country set a value for this parameter. Pyriproxyfen WHO Guideline value* No value established in 4th edition, previously 0.3 mg/l Number of countries and territories setting a regulatory / guideline value 5 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than previous WHO Guideline 1 Number of countries and territories setting the previous WHO Guideline 4 Number of countries and territories setting a regulatory / guideline value less than previous WHO Guideline 0 Maximum value set 0.4 mg/l Minimum value set 0.3 mg/l Median value 0.3 mg/l *Under the WHO Pesticides Evaluation Scheme (WHOPES) the recommended dosage of pyriproxyfen in potable water in containers should not exceed 0.01mg/l. Pyroproxifen is a pesticide used for vector control in drinking-water sources and containers. While the 3rd edition of the GDWQ included a GV of 0.3 mg/l, the 4th edition of the GDWQ does not specify a value for pyriproxyfen as it is not considered appropriate to establish guideline values for vector control pesticides. However, it has been included here because a 56 GV was set in the 3rd edition, and five of the countries and territories retain a value for this parameter. Simazine WHO Guideline value 0.002 mg/l Number of countries and territories setting a regulatory / guideline value 24 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 4 Number of countries and territories setting the WHO Guideline 19 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.02 mg/l Minimum value set 0.0015 mg/l Median value 0.002 mg/l Simazine was specified by 24 countries and territories, with the majority specifying the GV. Sodium Dichloroisocyanurate WHO Guideline value 50 mg/l Number of countries and territories setting a regulatory / guideline value 0 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 No country set a value for this parameter. 57 Styrene WHO Guideline value 0.02 mg/l (C)* Number of countries and territories setting a regulatory / guideline value 24 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 5 Number of countries and territories setting the WHO Guideline 18 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.1 mg/l Minimum value set 0.015 mg/l Median value 0.02 mg/l *Concentrations at or below the health-based guideline value may affect the appearance, taste or odour of the water, leading to consumer complaints Twenty-four of the 104 countries and territories surveyed specified a value for styrene, with the majority specifying the GV. Terbuthylazine WHO Guideline value 0.007 mg/l Number of countries and territories setting a regulatory / guideline value 7 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 5 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.01 mg/l Minimum value set 0.007 mg/l Median value 0.007 mg/l Seven countries and territories specified a value for terbuthylazine, and of these, five specified the GV. 58 Tetrachloroethene WHO Guideline value 0.04 mg/l Number of countries and territories setting a regulatory / guideline value 70 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 22 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 46 Maximum value set 0.05 mg/l Minimum value set 0.001 mg/l Median value 0.01 mg/l Tetrachloroethene is among the most specified organic parameters, and one of few parameters where the majority of countries and territories specifying a value set it below the GV. Trichloroacetic acid WHO Guideline value 0.2 mg/l Number of countries and territories setting a regulatory / guideline value 18 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 10 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 8 Maximum value set 0.2 mg/l Minimum value set 0.02 mg/l Median value 0.2 mg/l Ten out of 18 countries and territories specifying a value for trichloroacetic acid specified the GV. 59 1,1,1-Trichloroethane WHO Guideline value None specified WHO Health-based value 2 mg/l Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO health-based value 1 Number of countries and territories setting the WHO health-based value 7 Number of countries and territories setting a regulatory / guideline value less than WHO health-based value 8 Maximum value set 2 mg/l Minimum value set 0.03 mg/l Median value 1.15 mg/l Of the 16 countries and territories specifying a value for 1,1,1-trichloroethane, seven specified the GV. Trichloroethene WHO Guideline value 0.02 mg/l (provisional P) Number of countries and territories setting a regulatory / guideline value 68 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 21 Number of countries and territories setting the WHO Guideline 7 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 40 Maximum value set 0.07 mg/l Minimum value set 0.001 mg/l Median value 0.01 mg/l Almost two thirds of the 104 countries and territories surveyed specified a value for trichloroethene, with the majority (40/68) specifying values less than the provisional GV. Several countries and territories specified 0.01 mg/l jointly with tetrachloroethene. 60 2,4,6-Trichlorophenol WHO Guideline value 0.2 mg/l (C)* Number of countries and territories setting a regulatory / guideline value 30 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 18 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 10 Maximum value set 0.3 mg/l Minimum value set 0.002 mg/l Median value 0.2 mg/l *Concentrations at or below the health-based guideline value may affect the appearance, taste or odour of the water, leading to consumer complaints The majority of countries and territories (18/30) specifying a value for this parameter specified the GV. 2,4,5-T (2,4,5-Trichlorophenoxy acetic acid) WHO Guideline value 0.009 mg/l Number of countries and territories setting a regulatory / guideline value 24 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 5 Number of countries and territories setting the WHO Guideline 17 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.1 mg/l Minimum value set 0.002 mg/l Median value 0.009 mg/l Twenty-four countries and territories specified a value for 2,4,5-Trichlorophenoxy acetic acid, and the majority of these parameter specified the GV. 61 Trifluralin WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 19 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 16 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.09 mg/l Minimum value set 0.02 mg/l Median value 0.02 mg/l Of the 19 countries and territories that specified a value for trifluralin the majority specified the GV. Trihalomethanes (Total) WHO Guideline value (the sum of the ratios of the concentrations for Bromodichloromethane, Bromoform, Chloroform and Dibromochloromethane to their guideline values) ≤1 Number of countries and territories setting a regulatory / guideline value 66 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value at the WHO Guideline 9 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 57 Maximum value set 1 Minimum value set 0.001 Median value 0.1 The GDWQ set out a fractionation approach for total trihalomethanes (THMs), in which the sum of the ratios of concentrations for bromodichloromethane, bromoform, chloroform and dibromochloromethane to their Gvs should not exceed 1. Information on these individual compounds is presented earlier in the section on organic parameters. The majority of the 66 countries and territories specifying a value for total THMs set a value below the GV, and only 10 specified a value for total THMs and a value for each of its constituent parameters. 62 Toluene WHO Guideline value 0.7 mg/l (C)* Number of countries and territories setting a regulatory / guideline value 34 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 4 Number of countries and territories setting the WHO Guideline 22 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 8 Maximum value set 1 mg/l Minimum value set 0.024 mg/l Median value 0.7 mg/l *Concentrations at or below the health-based guideline value may affect the appearance, taste or odour of the water, leading to consumer complaints Thirty-four countries and territories specified a value for toluene, with the majority specifying the GV. Vinyl Chloride WHO Guideline value 0.0003 mg/l Number of countries and territories setting a regulatory / guideline value 61 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 50 Number of countries and territories setting the WHO Guideline 11 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.02 mg/l Minimum value set 0.0003 mg/l Median value 0.0005 mg/l The majority of countries and territories specifying a value for vinyl chloride set 0.0005 mg/l, greater than the GV of 0.0003 mg/L. 63 Xylenes WHO Guideline value 0.5 mg/l (C)* Number of countries and territories setting a regulatory / guideline value 31 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 6 Number of countries and territories setting the WHO Guideline 20 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 5 Maximum value set 10 mg/l Minimum value set 0.05 mg/l Median value 0.5 mg/l *Concentrations at or below the health-based guideline value may affect the appearance, taste or odour of the water, leading to consumer complaints Thirty-one countries and territories specified a value for xylenes, and almost two thirds of these set the GV. 64 Parameters relating to acceptability, taste and odour and appearance The GDWQ identify 26 chemically derived parameters and four biologically derived parameters relating to acceptability, taste, odour and appearance. The importance of these parameters is that if the water is unacceptable to consumers, it may lead to rejection of the water, and use of other aesthetically more acceptable but potentially less-safe waters. Generally the concentrations that cause rejection are significantly lower than those of concern for health. As such, with the exception of manganese, which is widely found in drinking-water sources, it may not be appropriate to directly regulate or monitor such parameters, as they may be addressed through a general requirement in the national standard or regulation that water be acceptable to the majority of consumers. For these parameters, the GDWQ may include a HBV, or a GV(C) in order to assist in determining a response when problems are encountered (and to provide reassurance with regard to possible health risks). Some parameters have recommended values, mainly based on consumer acceptance. All the countries and territories in the survey specified values for some of the chemical and physical parameters. Three countries and territories included general statements that potable water should be free of algae. Most of the values that were set were guidance or indicator levels rather than mandatory standards. The acceptability parameters most often specified were pH (hydrogen ion) (specified by 103 countries and territories), chloride (100), iron (99), aluminium and sulfate (97). The least specified parameters were petroleum oils (3), and dissolved oxygen (4). In addition, 79 countries and territories had descriptive requirements for the taste parameter, and 78 for the odour parameter, such as: “acceptable to most consumers”, “not offensive”, “not objectionable”, “acceptable to consumers and no abnormal change”. Eighteen countries and territories had numerical values for the odour parameter and eleven for the taste parameter. The details for copper, chlorine, 1,2- and 1,4-dichlorobenzene, ethylbenzene, manganese, styrene, toluene, 2,4,6-trichlorophenol and xylenes appear already in the sections on inorganic or organic parameters as appropriate. 65 Aluminium WHO Guidance A GV has not been established for aluminium although the GDWQ note that average residuals should not exceed levels needed to optimize coagulation in drinking-water plants that use aluminium-based coagulants (0.1-0.2 mg/l). It also notes that a health- based value of 0.9 mg/l could be derived, but this exceeds practicable levels based on coagulation in treatment plants. Number of countries and territories setting a regulatory / guideline value 97 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline recommendation of 0.2 mg/l 4 Number of countries and territories setting a regulatory / guideline value at the WHO Guideline recommendation of 0.2 mg/l 84 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline recommendation of 0.2 mg/l 10 Maximum value set 0.5 mg/l Minimum value set 0.03mg/l Median value 0.2 mg/l GDWQ also note that aluminium concentrations greater than 0.1-0.2 mg/l can lead to aesthetic issues All but fourteen of the 97 countries and territories specifying a value for aluminium set a value of 0.2 mg/l. Ammonium WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 81 (out of 104) Maximum value set 3 mg NH4/l Minimum value set 0.05 mg NH4/l Median value 0.2 mg NH4/l The threshold odour concentration of ammonia at alkaline pH is approximately 1.5 mg/l, and a taste threshold of 35 mg/l has been proposed for the ammonium cation. Ammonia is not of direct relevance to health at these levels, and no health-based guideline value has been 66 proposed. Eighty-one countries and territories specified a value for ammonium, with 47 specifying 0.5 mg NH4/l; 20 specifying 1.5 mg NH4 /l, and the rest specifying values ≤ 1 mg NH4 /l. Calcium WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 31 (out of 104) Maximum value set 500 mg/l Minimum value set 30 mg/l Median value 150 mg/l The GDWQ advise a taste threshold for calcium ion of 150 – 300 mg/l, depending on the associated anion. Thirty-one countries and territories specified a value for this parameter, although it was not always clear if the value specified was quoted as calcium ion or as a calcium salt. Chloramines WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 6 (out of 104) Maximum value set 4 mg/l Minimum value set 0.15 mg/l Median value 3.5 mg/l A GV of 3 mg/L is set for monochloramine, and the information is presented in the inorganic parameters section. No HBV or GV is set for di- and trichloramines, as the available data is inadequate to derive a health-based GV. For dichloramine, the organoleptic effects between 0.1 and 0.5 mg/l were found to be “slight” and “acceptable”. Odour and taste thresholds of 0.15 and 0.13 mg/l were reported, respectively. An odour threshold of 0.02 mg/l has been reported for trichloramine, and it has been described as “geranium”. Six countries and territories set a value for chloramines, ranging from 0.15 to 4 mg/l. 67 Chloride WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 100 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline recommendation of 250 mg/l 15 Number of countries and territories setting a regulatory / guideline value at the WHO Guideline recommendation of 250 mg/l 77 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline recommendation of 250 mg/l 8 Maximum value set 1200 Minimum value set 20 Median value 250 Chloride is one of the most specified aesthetic parameters, with 100 countries and territories specifying a value. The GDWQ mention that concentrations in excess of 250 mg/l are increasingly likely to be detected by taste, and most countries and territories specified this value. Chlorobenzene WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 7 (out of 104) Maximum value set 0.3 mg/l Minimum value set 0.001 mg/l Median value 0.1 mg/l No GV has been set for chlorobenzene, however the GDWQ mention that odour thresholds of 0.002–0.01 and 0.0003–0.03 mg/l have been reported for 1,2- and 1,4-dichlorobenzene, respectively. Odour thresholds of 0.01, 0.005–0.03 and 0.05 mg/l have been reported for 1,2,3-, 1,2,4- and 1,3,5-trichlorobenzene, respectively. A taste and odour threshold concentration of 0.03 mg/l has been reported for 1,2,4-trichlorobenzene. Seven countries and territories specified a value for chlorobenzene, ranging from 0.001 to 0.3 mg/L. 68 Chlorophenols (other than 2,4,6-trichlorophenol) WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 9 (out of 104) Maximum value set 0.3 mg/l Minimum value set 0.0001 mg/l Median value 0.003 mg/l Chlorophenols generally have very low taste and odour thresholds. The taste thresholds in water for 2-chlorophenol, and 2,4-dichlorophenol are 0.0001,and 0.0003 mg/l, respectively. Odour thresholds are 0.01 and 0.04 mg/l, respectively. Nine countries and territories specified a value for this parameter, ranging from 0.0001 to 0.3 mg/L. Colour WHO Guideline value (true colour units) None set Number of countries and territories setting a regulatory / guideline value 80 with numerical values (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline recommendation of 15 TCU mg/l 20 Number of countries and territories setting a regulatory / guideline value at the WHO Guideline recommendation of 15 TCU mg/l 44 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline recommendation of 15 TCU 16 Maximum value set 50 TCU Minimum value set 0.5 TCU Median value 15 TCU The GDWQ suggest 15 TCU as the level for consumer acceptance. The majority (44/80) of countries and territories setting a value for the colour parameter set 15 TCU. Twenty-two countries and territories had only an advisory statement of “acceptable to consumers and no change”, and one country specified “colourless”. 69 Dissolved oxygen WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 4 (out of 104) Maximum value set 8 mg/l Minimum value set 4 mg/l Median value 6 mg/l Dissolved oxygen is one of the least specified parameters, with only four countries and territories specifying values ranging from 4 to 8 mg/L. Hardness WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 57 (out of 104) Maximum value set 1000 mg CaCO3/l Minimum value set 100 mg CaCO3/l Median value 500 mg CaCO3/l It was assumed that all quoted figures referred to mg CaCO3/l although this was not always clear, especially when no method was specified. Fifty-seven countries and territories set a value for this parameter, and several others also had target or desirable levels below their maximum value. Hydrogen sulphide WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 27 (out of 104), with numerical values Maximum value set 0.1 mg/l Minimum value set 0 mg/l Median value 0.05 mg/l All 27 countries and territories set values within the taste threshold of 0.05 – 0.1 mg/l quoted in the GDWQ. 70 Iron WHO Guideline value None set* Number of countries and territories setting a regulatory / guideline value 99 (out of 104) Maximum value set 2 mg/l Minimum value set 0.2 mg/l Median value 0.3 mg/l *However, the GDWQ indicates a precautionary level of 2 mg/l, which does not present a hazard to health Almost all countries and territories set a value for this parameter. Fifteen countries and territories set a value above the GDWQ aesthetic limit of 0.3 mg/l at which staining of laundry and fixtures may occur. Thirty-five countries and territories specified the lowest value of 0.2 mg/L. Magnesium WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 34 (out of 104) Maximum value set 1,000 mg/l Minimum value set 10 mg/l Median value 100 mg/l The GDWQ advise that the taste threshold for magnesium is probably less than the 150 – 300 mg/l range for calcium. Thirty-four countries and territories specified a value for this parameter, although it was not always clear whether the value specified was quoted as magnesium ion or as a magnesium salt. 71 Monochlorobenzene WHO Guideline value None specified WHO Health-based value 0.3 mg/l Number of countries and territories setting a regulatory / guideline value 14 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO health-based value 0 Number of countries and territories setting the WHO health-based value 4 Number of countries and territories setting a regulatory / guideline value less than WHO health-based value 10 Maximum value set 0.3 mg/l Minimum value set 0.003 mg/l Median value 0.1 mg/l Taste and odour thresholds of 0.01–0.02 mg/l and odour thresholds ranging from 0.04 to 0.12 mg/l have been reported for monochlorobenzene. Of the 14 countries and territories setting a value for this parameter, the majority specified a value below the HBV. Odour WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 19, with numerical values (out of 104) Maximum value set 6 DN Minimum value set 2 DN Median value 3 DN All countries and territories specifying a numerical value set dilution number (DN) as 3, except for two countries that specified 2 and 6. Seventy-eight countries and territories had an advisory statement such as “acceptable to consumers and no abnormal change”, “non-objectionable” or “not detectable”. 72 Petroleum Oils WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 3 (out of 104) Maximum value set 0.3 mg/l Minimum value set 0.1 mg/l Median value 0.2 mg/l Petroleum oils can give rise to the presence of a number of low molecular weight hydrocarbons that have low odour thresholds in drinking-water. Benzene, toluene, ethylbenzene and xylenes (BTEX) are considered in the organic parameters section. Only three countries and territories set values for this parameter. pH Maximum WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 103 (out of 104) Maximum value set pH 9.7 Minimum value set pH 8 Median value pH 8.5 The GDWQ do not establish a GV for pH, as it usually has no direct impact on consumers at levels found in drinking-water. It is however an important operational parameter, and the GDWQ indicate an optimum pH range of 6.5-8.5. Only one country out of the 104 included in the survey did not specify a value for this parameter. Forty-eight countries and territories specified a value above the GDWQ suggested pH 8.5, but many included the note that chlorine disinfectant is only effective below pH 8. The highest value of pH 9.7 was set by one country, and was described as an operational limit. pH Minimum WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 102 (out of 104) Maximum value set pH 7 Minimum value set pH 5 Median value pH 6.5 73 Only two countries did not specify a value for this parameter. Eight countries and territories specified a value below the optimum range discussed in the GDWQ of pH 6.5. Sodium WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 81 (out of 104) Maximum value set 400 mg/l Minimum value set 100 mg/l Median value 200 mg/l The GDWQ notes that at room temperature, the average taste threshold for sodium is 200 mg/l. Seventy-one of the 81 countries and territories set this value, and only seven set a higher value. Sulfate WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 97 (out of 104) Maximum value set 800 mg/l Minimum value set 50 mg/l Median value 250 mg/l The GDWQ suggest taste impairment is minimal below 250 mg/l but can be up to 1,000 mg/l for calcium sulfate. Ninety-seven countries and territories set a value for this parameter, and the majority (66) specified 250 mg/l. Synthetic Detergents (Anionic) (Surfactants) WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 33 (out of 104) Maximum value set 2 mg/l Minimum value set 0.01 mg/l Median value 0.5 mg/l The GDWQ advise that the concentration of detergents in drinking-water should not be allowed to reach levels giving rise to either foaming or taste problem. Thirty-three countries and territories specified a value for this parameter, of these, 14 set 0.5 mg/l. 74 Taste WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 12 (out of 104), with numerical values Maximum value set 6 DN Minimum value set 2DN Median value 3 DN Twelve countries and territories specified numerical values for taste, and nine of these specified 3 DN. Seventy-nine countries and territories had an advisory statement such as “acceptable to consumers and no abnormal change”, “non-objectionable” or “inoffensive”. Temperature WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 18 (out of 104) Maximum value set 35oC Minimum value set 15oC Median value 25oC None of the values for temperature were mandatory, being guiding levels or operational goals. None of the countries and territories’ documents indicated what would happen if temperatures rose above the suggested value. In addition to those with numerical values, seven countries and territories had descriptive levels such as: 2.5 oC above normal; “not objectionable”; “air temperature plus 3 oC”; “acceptable”; and “ambient”. Total dissolved solids WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 66 (out of 104) Maximum value set 2500 mg/l Minimum value set 200 mg/l Median value 1000 mg/l Sixty-six countries and territories set a value for this parameter. There was a wide range of values; from 200 mg/l to 2,500 mg/l. Thirty-six countries and territories specified 1000 mg/l, eleven specified 500 mg/l. 75 Trichlorobenzenes (total) WHO Guideline value None specified WHO Health-based value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 11 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO health-based value 3 Number of countries and territories setting the WHO health-based value 8 Number of countries and territories setting a regulatory / guideline value less than WHO health-based value 0 Maximum value set 0.03 mg/l Minimum value set 0.02 mg/l Median value 0.02 mg/l Eleven countries and territories specified a value for trichlorobenzenes, and of these, eight set the HBV of 0.02 mg/l. Odour thresholds of 0.01, 0.005–0.03 and 0.05 mg/l have been reported for 1,2,3-, 1,2,4- and 1,3,5-trichlorobenzene, respectively. A taste and odour threshold concentration of 0.03 mg/l has been reported for 1,2,4-trichlorobenzene. Turbidity WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 85 (out of 104), with numerical values Maximum value set 25 NTU Minimum value set 0.3 NTU Median value 5 NTU The GDWQ notes that turbidity should ideally be <1 NTU for water to be disinfected and that large well-run municipal supplies should be able to achieve turbidity levels of < 0.5 NTU at all times, with an average of </= 0.2 NTU. It also notes that turbidity levels of 4 NTU and above is visible to the naked eye. Sixteen countries and territories specified a value of 1 NTU or less. Many values were accompanied by comments, including one country that specified 20 NTU but stated that the monthly average of results must not exceed 2 NTU; and another that quoted 5 as an aesthetic limit but 1 NTU as an operational limit. Fifteen countries and territories had descriptive statements only such as “acceptable to consumers and no abnormal change”. 76 Zinc WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 74 (out of 104) Maximum value set 15 mg/l Minimum value set 1 mg/l Median value 5 mg/l The GDWQ note that zinc concentrations at around 4 mg/l may affect the taste of water. Thirty-five out of 72 countries and territories reporting a value for this parameter specified 3 mg/l or less. 77 Radiological parameters The GDWQ suggest screening levels for gross alpha and gross beta activity, as the process of identifying individual radionuclides is too cost-intensive for routine monitoring given their generally low concentration. If the screening levels for gross alpha and gross beta activity suggested by WHO are not being exceeded, the individual dose criterion (i.e. total dose) of 0.1 milliSieverts per year (mSv/year) will usually not be exceeded either. The idea of screening levels is that radioactivity should be assessed against these during routine monitoring. If the screening levels are being exceeded after having taken further samples to validate the findings, the contribution of K-40 (beta) should be subtracted from the gross beta activity following a separate determination of total potassium. If the screening values are still being exceeded, an analytical strategy for individual radionuclides should be determined. In general, countries and territories that specified values for radiological parameters did not deviate significantly from the GDWQ. Forty-eight countries and territories specified screening values for gross alpha and gross beta activity, two in terms of a ratio or annual dose. Some expressed their values in terms of Picocurie per litre (pCi/l); these have been converted to their equivalents as Becquerel per litre (Bq/l) for this report. Thirty five countries and territories specified a value for total dose in terms of mSv/yr. Only three of these also specified values for gross alpha and beta activity. The GDWQ list guidance levels for 191 radionuclides. However, most countries and territories specified values for only a few of these, including: radon (seven); radium-226 (seven); strontium-90 (five). Where countries and territories specified values for gross alpha and beta activity and total dose, most included advice on the steps that should be taken if any of these values were exceeded. 78 Total Dose / Individual Dose Criteria WHO/IDC guidance 0.1 mSv/year* Number of countries and territories setting a regulatory / guideline value 36 (out of 104) Number of countries and territories setting a regulatory / guidance level greater than WHO/IDC guidance 2 Number of countries and territories setting the WHO IDC guidance 34 Number of countries and territories setting a regulatory / guidance level less than WHO/IDC guidance 0 Maximum value set 1 mSv/year Minimum value set 0.1 mSv/year Median value 0.1 mSv/year *This value is translated into operational targets to be measured by water suppliers and regulators as the screening values (gross alpha and gross beta, which are listed in the tables below) and guidance levels (which are listed in Table 9.2 of Chapter 9 of the GDWQ). The GDWQ notes that the IDC represents a very low level of health risk and also refers to the International Radiation Basic Safety Standards (BSS), (IAEA, 2014) reference level. The BSS, which is co-sponsored by eight international organizations including WHO, has established a reference level for the radiation dose due to the consumption of drinking-water of 1 mSv/year. It is generally advisable for countries to establish a national standard between 0.1 and 1 mSv/year, where 0.1 mSv/year is achievable for most countries. Almost all countries have established their IDC as 0.1 mSv/year, and the EC Council Directive 2013/51/EURATOM also adopted a total indicative dose of 0.1 mSv/year. Only two countries out of the 36 that specified a value for this parameter set a value above 0.1 mSv/year. Gross alpha activity WHO Screening level 0.5 Bq/l Number of countries and territories setting a regulatory / guidance level 48 (out of 104) Number of countries and territories setting a regulatory / guidance level greater than WHO Screening level 3 Number of countries and territories setting the WHO Screening level 12 Number of countries and territories setting a regulatory / guidance level less than WHO Screening level 33 Maximum value set 0.56 Bq/l Minimum value set 0.01 Bq/l Median value 0.1 Bq/l Twelve countries and territories specified the WHO screening level (or its equivalent when their values are converted from pCI/l). 79 Gross beta activity WHO Screening level 1 Bq/l Number of countries and territories setting a regulatory / guidance level 48 (out of 104) Number of countries and territories setting a regulatory / guidance level greater than WHO Screening level 5 Number of countries and territories setting the WHO Screening level 37 Number of countries and territories setting a regulatory / guidance level less than WHO Screening level 6 Maximum value set 2.0Bq/l Minimum value set 0.1 Bq/l Median value 1 Bq/l Thirty-seven countries and territories specified the WHO screening level (or its equivalent when their values are converted from pCI/l). Five countries specified values above the WHO screening level, and six specified values less than the WHO screening level. 80 Microbiological parameters The GDWQ identify 43 microbial parameters, which include bacterial, viral, protozoan, and helminth pathogens, as well as toxic cyanobacteria. The verification of microbial water safety is normally based on testing of indicator organisms, and the GDWQ include a GV for Escherichia coli (E. coli) or thermotolerant coliforms). Countries and territories in the survey designated numerical standards for 24 microbiological parameters. However, nine of these parameters were designated by only one country and a further nine by less than ten countries and territories. Values for E. coli (or faecal coliforms or thermotolerant coliforms) were specified by 102 countries and territories, then total coliforms (97 countries and territories), enterococci (faecal streptococci) (46 countries and territories), sulphite-reducing Clostridia (Clostridium perfringens) (44 countries and territories), total heterotrophic bacteria at 22°C(19 countries and territories) and total heterotrophic bacteria at 37°C (13 countries and territories). The other parameters were: Enteric viruses and Pseudomonas aeruginosa (eight countries and territories); Cryptosporidium and Giardia (five countries and territories); Salmonella, somatic coliphages and Staphlococcus aureus (four countries and territories); pathogenic protozoa and Shigella (three countries and territories); and amoeba, Vibrio cholera, free living organisms, helminths, Legionella, nematodes, parasites and plankton (one country). The normal value for microbiological parameters, other than heterotrophic bacteria, was zero or absent per volume (usually 100 ml for bacterial parameters and 10 litres for protozoa) although many countries and territories’ values accepted that coliform bacteria would be detected in samples on occasions. In addition to setting values for some microbiological parameters, many countries and territories’ documentation included a statement the same as or similar to that in the European Drinking-water Directive that drinking-water “shall be free from any micro-organisms and parasites which, in numbers or concentrations, constitute a potential danger to human health”. 81 Clostridium perfringens (Sulphite-reducing anaerobes) WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 44 (out of 104) Maximum value set 0 per 100 ml Minimum value set 0 per 100 ml Median value 0 per 100 ml The GDWQ state that Clostridium perfringens has only limited value as a possible indicator of enteric viruses and protozoan (oo)cysts but may be useful as an indicator of the effectiveness of filtration processes. All countries and territories specifying a value for this parameter specified zero per 100 ml (or in some cases 20 ml or 50 ml) for this parameter. Coliform bacteria (Total) WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 98 (out of 104) Maximum value set 150 per 100 ml Minimum value set 0 per 100 ml Median value 0 per 100 ml The GDWQ highlight that total coliform bacteria include organisms that can survive and grow in water so they are not useful as an indicator of faecal pathogens. It recommends that total coliforms should be absent immediately after treatment and presence of these organisms indicates inadequate treatment. Few countries and territories appeared to recognize this in their setting values. While six countries and territories did not specify a value for total coliforms, the others generally specified a value of zero for this parameter. Some specified <1.1 per 100 ml for analysis by most probable number technique. Where the value specified was greater than zero (e.g. 10 per 100 ml; 6 per 100 ml; or 3 per 100 ml), in most cases this was qualified by not detecting coliform bacteria in two consecutive samples or 95% of annual samples or both. One country specified 10 per 100ml as an operational value; another specified 100 coliform bacteria per 100 ml in a maximum of 1% of samples;10 per 100 ml in a maximum of 4% of samples; and “not detected” in a minimum of 95% of samples. One country designated the highest value as a maximum allowable range of 50 – 150 per 100 ml, but a recommended maximum limit of 10 per 100 ml. 82 Enterococci (Faecal streptococci) WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 47 (out of 104) Maximum value set 0 per 100 ml Minimum value set 0 per 100 ml Median value 0 per 100 ml The GDWQ advise that intestinal enterococci can be used as an indicator of faecal pollution and may survive longer in water than E coli. All countries and territories specifying a value for this parameter specified zero per 100 ml, and one specified that the value should be zero per 100 ml in 95% of samples (where more than 20 are taken annually) and not be present in consecutive samples. Escherichia coli (Faecal coliforms, Thermotolerant coliforms) WHO Guideline value Must not be detectable in any 100ml sample Number of countries and territories setting a regulatory / guideline value 103 (out of 104) Maximum value set 1 per 100 ml Minimum value set 0 Median value 0 For the purposes of this survey, faecal coliforms and thermotolerant coliforms have not been counted separately where they have been specified by countries and territories in addition to E coli because the value has always been zero per 100 ml. The GDWQ advise that the presence of E coli (or thermotolerant coliforms) provides evidence of recent faecal contamination. All countries and territories specified a value of zero per 100 ml except one country which specified 1 per 100 ml in a maximum of 1% of samples. One country did not specify a value for this parameter, just specifying zero per 100 ml for coliforms. 83 Total heterotrophic bacteria 22oC WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 19 (out of 104) Maximum value set 10,000 cfu per ml Minimum value set 5 cfu per ml Median value 100 cfu per ml The GDWQ advise that the test for this parameter has little value as an indicator of pathogen presence but can be useful in operational monitoring as a treatment and disinfectant indicator and for assessing the cleanliness of distribution systems. The objective is to keep numbers as low as possible. The EU countries specified “no abnormal change” for this parameter. Total heterotrophic bacteria 37oC WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 14 (out of 104) Maximum value set 500 cfu per ml Minimum value set 0 cfu per ml Median value 100 cfu per ml The GDWQ advise that the test for this parameter has little value as an indicator of pathogen presence but can be useful in operational monitoring as a treatment and disinfectant indicator and for assessing the cleanliness of distribution systems. The objective is to keep numbers as low as possible. 84 Additional parameters In the documentation used for this survey countries and territories specified 865 numerical values for 287 inorganic, organic, aesthetic and physical parameters that do not have a WHO GV, HBV or aesthetic limit. The additional parameters with numerical standard values most often specified, and reported in this section are: Conductivity (51 countries and territories); total polynuclear aromatic hydrocarbons (PAH) (44); oxidizability (permanganate value) (43); phenols (35); formaldehyde (19); silver (24); potassium (12); and propanil (11). Conductivity WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 51 (out of 104) Maximum value set 2700 S/cm Minimum value set 170 S/cm Median value 2500 S/cm Almost half (51/104) of the countries and territories included in the survey specified a value for conductivity. A wide range of values were specified, from 170 to 2,700 S/cm. Twenty-eight countries and territories specified 2500 S/cm. Formaldehyde WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 19 (out of 104) Maximum value set 1 mg/l Minimum value set 0.02 mg/l Median value 0.9 mg/l The GDWQ advise that this parameter occurs in drinking-water at concentrations well below those of health concern and specifies a tolerable concentration of 2.6 mg/l for ingested formaldehyde. Nineteen countries and territories specified a value for formaldehyde, and of these, eleven set 0.9 mg/l. 85 Oxidizability (permanganate value) WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 43 (out of 104) Maximum value set 20 mg/l Minimum value set 3 mg/l Median value 5 mg/l Forty-three countries and territories specified a value for this parameter, with the majority (37/43) setting mg/l. Total Polynuclear Aromatic Hydrocarbons (PAH) WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 44 (out of 104) Maximum value set 0.01 mg/l Minimum value set 0.0001 mg/l Median value 0.0001 mg/l The GDWQ do not advise a health-based guideline value for total PAH. Benzo(a)pyrene has a health-based value of 0.0007 mg/l (see organic parameters). For fluoranthene it advises that it occurs in drinking-water at concentrations well below those of health concern but a health- based value of 0.004 can be calculated on available data. Forty-four countries and territories specified a value for total PAHs, of these, 33set 0.0001 mg/l. Phenols WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 35 (out of 104) Maximum value set 0.3 mg/l Minimum value set 0.0003 mg/l Median value 0.002 mg/l The GDWQ do not advise a health-based guideline value for total phenols. 2,4,6- Trichlorophenol has a provisional GV (C) of 0.2 mg/l (see organic parameters), and summary information on chlorophenols other than 2,4,6-trichlorophenol is presented in the sections on acceptability parameters. Thirty-five countries and territories specified a value for phenols. Almost half (15/35) set 0.002 mg/l. 86 Potassium WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 12 (out of 104) Maximum value set 50 mg/l Minimum value set 1.5 mg/l Median value 10 mg/l The GDWQ advise that currently, there is no evidence that potassium levels in municipally treated drinking-water, even water treated with potassium permanganate, are likely to pose any risk for the health of consumers. It is not considered necessary to establish a health-based guideline value for potassium in drinking-water. Twelve countries and territories specified a value for potassium. Propanil WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 11 (out of 104) Maximum value set 0.7 mg/l Minimum value set 0.02 mg/l Median value 0.02 mg/l The GDWQ advise that although a health-based value for propanil can be derived, this has not been done, because propanil is readily transformed into metabolites that are more toxic. Two of these metabolites, 3,4-dichloroaniline and 3,3′ ,4,4′ -tetrachloroazobenzene, are more toxic and more persistent than the parent compound. Therefore, a guideline value for propanil is considered inappropriate and there are inadequate data on the metabolites to allow the derivation of guideline values for them. All of the eleven countries and territories setting a value for propanil specified 0.02 mg/l except one, which specified 0.7 mg/l. No country or territory specified a value for metabolites of propanil. 87 Silver WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 24 (out of 104) Maximum value set 0.1 mg/l Minimum value set 0.01 mg/l Median value 0.05 mg/l The GDWQ advise that the available data is inadequate to permit the derivation of a health- based guideline value; however, a concentration of 0.1mg/l could be tolerated without risk to health. Twenty-four countries and territories specified a value for silver, and none set a value above 0.1 mg/l. 88 Conclusion The GDWQ emphasize the importance of setting risk-based standards and adopting the specifications in the guidelines to local resources and needs. The GDWQ do not only provide guidance on standard-setting, but also on a holistic water safety framework that includes the establishment of national standards, as well as preventive risk management approaches (e.g. Water Safety Plans), and independent surveillance. For the purpose of this report, only the standards that countries and territories are specifying for different water quality parameters were reviewed. In that context, it was found that the GDWQ play an overall significant role in countries and territories’ setting of values that define drinking-water quality. More than half of the countries and territories in the survey reference the GDWQ directly (e.g. Iceland) or indirectly (e.g. Norway) by referencing other countries and territories which referenced the GDWQ. This figure is actually likely to be higher as the full value standard was not always available. Another limitation of this report is that direct comparison between countries and territories is difficult because standards in different countries and territories can be mandatory, recommended and/or risk-based. Direct comparison is further difficult and should be approached with caution, as national standards should be developed considering the local context. It must also be kept in mind that countries and territories review their specification for drinking-water quality with a different rhythm than to when updates to the GDWQ are published. However, the values included in the GDWQ and their role in providing orientation to countries and territories is underlined by the number of countries and territories making reference to the GDWQ in their specifications, and in a great many cases specifying GVs. 89 References and source documentation Guidelines for Drinking-water Quality. Fourth Edition. Geneva: World Health Organization; 2011: (http://www.who.int/water_sanitation_health/publications/dwq-guidelines-4/en/, accessed 28 November 2017). Developing Drinking-water Quality Regulations and Standards: General Guidance with a Special Focus on Countries with Limited Resources. Geneva: World Health Organization; in press. Albania Law on Regulations for Hygiene-Sanitation for the Control of Quality of Drinking-water, etc. Decision Nr. 145, date 26.02.1998 approved by Council of Ministers. Albanian Standard: STASH 3904:1997. Argentina Codigo Alimentario Argentino Resolution Conjunta 68/2007 y 196/2007 Modification Australia National Water Quality Management Strategy. Australian Drinking-water Guidelines 6 2011 Austria Verordnung des Bundesministers für soziale Sicherheit und Generationen über die Qualität von Wasser für den menschlichen Gebrauch (Trinkwasserverordnung – TWV) August 2001 Bangladesh Water Safety Framework in Bangladesh, Ministry of Local Government, Rural Development and Cooperatives, Government of the People’s Republic of Bangladesh. October 2011. Belarus Питьевая вода. Г игиенические требования к качеству воды централизованных систем питьевого водоснабжения. Постановлением Главного государственного санитарного врача Республики Беларусь от 19 октября 1999 № 46 (Sanitary rules and norms "Drinking-water. Hygienic requirements for water quality of centralized drinking-water supply systems”.) Decree of the Chief State Sanitary Doctor 90 The Republic of Belarus October 19, 1999 № 46 Belgium L’arrêté du Gouvernement de la Région de Bruxelles-Capitale (AGRBC) du 24 janvier 2002 relatif à la qualité de l’eau distribuée par réseau Le décret du 12.12.2002 (MB 14.01.2003 – err 20.05.2003) – relatif à la qualité de l’eau destinée à la consommation humaine. Het besluit van de Vlaamse regering van 13 december 2002 houdende reglementeringen inzake de kwaliteit en levering van water bestemd voor menselijke consumptie, Bolivia Norma Boliviana NB 512 Agua Potable Requisitos 2004 Botswana BOS 32 : 2009 Water Quality: Drinking-water Brazil Norma de Qualidade da Agua Para Consumo Humano, Portaria No 2914 2011 Cambodia Drinking-water Quality Standards (Ministry of Industry, Mines and Energy) 2004 Canada Health Canada. Guidelines for Canadian Drinking-water Quality 2010 Chile Agua potable - Requisitos. Norma Chilena Oficial NCh409/1.Of2005 China GB 5749-2006 Standards for drinking-water quality Taiwan, China Drinking-water Quality Standards (Drinking-water Management Act) 2009 Colombia Normas oficiales para la calidad del agua Colombia 1994 91 Croatia O Zdravstvenoj Ispravnosti Vode Piće (Ministarstvo Zdravstvai Socijalne Skrbi (1593) (Regulations on drinking-water) 2008, Ministry of Social Welfare Costa Rica Reglamento para la Calidad del Agua Potable 2005 Cuba Agua Potable Requisitos Sanitarios NC 93-02:1997 Cyprus The Quality of Water Intended for Human Consumption (Monitoring and Control) Law of 2001 (N.87(I)/2001) and Regulations. Czech Republic Vyhláška č. 252/2004 Sb. kterou se stanoví hygienické požadavky na pitnou a teplou vodu a četnost a rozsah kontroly pitné vody Denmark Bekendtgørelse om vandkvalitet og tilsyn med vandforsyningsanlæg 1) I medfør af § 5, § 8, § 8 a, § 55, stk. 7, § 56, § 57, stk. 2, § 58, stk. 3 og 4, § 59, stk. 1 og 3, § 60, stk. 2, § 69 a, § 71 a og § 84, stk. 2, i lov om vandforsyning mv, jf. lovbekendtgørelse nr. 1199 af 30. september 2013, Dominican Republic Decreto 42-05 Establece el Reglamento de Aguas Consumo Humano, Secretaría de Estado de Salud Pública y Asistencia Social (SESPAS) 2005 Ecuador Norma Técnica Ecuatoriana NTE INEN 1 108:2011Agua Potable Requisitos Egypt Decree of Minister of Health No (108) and (301) 1995 El Salvador Norma Salvadoreña Obligatoria: NSO 13.07.02:08 "Agua.Agua Envasada (Primera Actualizacion)" 92 Estonia Joogivee kvaliteedi- ja kontrollinõuded ning analüüsimeetodid Vastu võetud 31.07.2001 nr 82 Ethiopia Drinking-water - Specifications ES 261:2001 European Union Council Directive 98/83/EC on the quality of water intended for human consumption Fiji Fiji National Drinking-water Standards 2011 Finland Terveysministeriön asetus talousveden laatuvaatimuksista 19.5.2000/461 France Arrêté du 11 janvier 2007 relatif aux limites et références de qualité des eaux brutes et des eaux destinées à la consommation humaine mentionnées aux articles R. 1321-2, R. 1321-3, R. 1321- 7 et R. 1321-38 du code de la santé publique Germany Verordnung über die Qualität von Wasser für denmenschlichen Gebrauch (Trinkwasserverordnung -TrinkwV 2001) Ghana Ghana Standard GS 175-1:2013. Water Quality - Specification for Drinking-water. 4th edition. Ghana Standards Authority. Greece Áñ. Öýëëïõ 892 11 Éïõëßïõ 2001 Guatemala Norma Guatemalteca Obligatoria Agua Potable 2000 Honduras República de Honduras Ministerio de Salud - Norma Técnica para la calidad del Agua 1995 93 Hungary 201/2001. (X. 25.) Korm. Rendelet az ivóvíz minőségi követelményeiről és az ellenőrzés rendjéről Iceland Reglugerd um neysluvatn 2001 India Drinking-water Specification Second revision of IS:10500 2012 Indonesia Nomor 492/Menkes/Per/IV/2010 Iraq The Standardization's Specification No 417 2001 Ireland Environmental Protection Agency Drinking-water Regulations 2014 Israel Public Health Regulations (Sanitary Quality of Drinking-water) 1974 Consolidated Version 2000 Italy Decreto Legislativo 2 febbraio 2001, n. 31 "Attuazione della direttiva 98/83/CE relativa alla qualita' delle acque destinate al consumo umano" Japan Ministerial Ordinance Concerning Drinking-water Quality Standards - 2010 Jordan Jordan Institute for Standards and Metrology. Technical Regulations: Water – Drinking water; 2008. (286:2008-5th edition) Kenya Kenya Bureau of Standards. Specification fir Drinking-water KS 05-459: Part 1:1996 94 Lao People’s Democratic Republic Decree for drinking-water quality standard in Lao People’s Democratic Republic and standard for checking of water resource No 953/MOH. 2003 Latvia Ministru kabineta noteikumi Nr.235 Rīgā 2003.gada 29.aprīlī (prot. Nr.23 71.§) Dzeramā ūdens obligātās nekaitīguma un kvalitātes prasības, monitoringa un kontroles kārtība Lebanon Ministry of Environment Decree No 52/1 - Standards for the Minimization of Pollution of Air, Water and Soil 2006 Lithuania Dėl lietuvos higienos normos HN 24:2003 “Geriamojo vandens saugos ir kokebės reikalavimai” Luxembourg Règlement grand-ducal du 7 octobre 2002 relatif à la qualité des eaux destinées à la consommationhumaine Malaysia National Standard for Drinking-water Quality 2004 Malta LN23 / 2004 Kwalità ta 'ilma maħsub għal regolamenti konsum tal-bniedem 2004 (LN23/2004 Quality of water intended for human consumption regulations 2004) Mexico Modificacion a la Norma Oficial Mexicana NOM-127-SSA1-1994, Salud ambiental. Agua para uso y consumo humano. Límites permisibles de calidad y tratamientos a que debe someterse el agua para su potabilización. Morocco Norm Marocaine NM 03.7.001 Qualité des eaux d'alimentation humane 2006 Mozambique Regulamento sobre a Qualidade da Água para o Consumo Humano 2004 95 Nepal National Drinking-water Quality Standards 2005 Netherlands Wet van 18 juli 2009, houdende nieuwe bepalingen met betrekking tot de productie en distributie van drinkwater en de organisatie van de openbare drinkwatervoorziening (Drinkwaterwet) New Zealand Drinking-water Standards for New Zealand 2005 (Revised 2008) Nicaragua Norma Regional de Calidad del Agua Comite Coordinador Regional de Instituciones de Agua Potable y Saneamiento de Centroamerica, Panama y Republica Dominicana – Capre 1994 Nigeria Nigerian Standard for Drinking-water Quality NIS 554: 2007 Norway FOR 2001-12-04 No 1372: Forskrift om vannforsyning og drikkevann Oman Omani Standard No 8/2006 Unbottled Drinking-water Pakistan National Standards for Quality Drinking-water 2009 Panama Reglamento Técnico DGNT-COPANIT 23-395-99 Agua, Agua Potable Definiciones y Requistos Generales Paraguay Ley General del Marco Regulatorio y Tarifario del Servicio de Agua Potable y Alcantarillado Sanitario Ley No 1.614/2000 Peru Reglamento de la Calidad del Agua para Consumo Humano. DS No 031-2010-SA 96 Philippines Philippine National Standards for Drinking-water 2007 Poland Rozporządzenia Ministra Zdrowia z dnia 29 marca 2007r. W sprawie jakości wody przeznaczonej do spoŜycia przez ludzi (Dz. U. Nr 61, poz. 417) Portugal Ministério do Ambiente, do Ordenamento do Território e do Desenvolvimento Regional Decreto-Lei no 306/2007 de 27 de Agosto Romania Lege nr 458(r1) din 08/07/2002. Privind calitatea apei potabile The Russian Federation II.Предельно допустимые концентрации (ПДК) химических веществ в воде водныхобъектов хозяйственно-питьевого и культурно-бытового водопользования (Permissible concentration (MPC) of chemicals in the water for drinking, cultural and domestic use) Resolution of the Sanitary Inspector of the The Russian Federationn Federation (30.04.2003 Moscow № 78 Овведении в действие ГН 2.1.5.1315-03) Rwanda Potable Water - Specification. Rwanda Standard RS435:2009 Rev 1:2011 Samoa Samoa National Drinking-water Standards 2008 Sierra Leone Draft Guidelines for Drinking-water Policy (Water Supply and Sanitation for Sierra Leone, United Nations Economic Commission for Africa) 2007 Singapore Environmental Public Health (Quality of Piped Drinking-water) Regulations 2008 Slovakia 97 Zbierka zákonov č. 496/2010 ktorým sa mení a dopĺňa nariadenie vlády Slovenskej republiky č. 354/2006 Z. z., ktorým sa ustanovujú požiadavky na vodu určenú na ľudskú spotrebu a kontrolu kvality vody určenej na ľudskú spotrebu Slovenia Rules on water intended for human consumption. Based on the Act Regulating the Sanitary Suitability of Foodstuffs, Products and Materials Coming into Contact with Foodstuffs (Official Gazette of RS, no. 52/00 and 42/02), Spain Real Deccreto 140/2003, de 7 Febrero, por el que se establecen los criterios sanitarios de la calidad del agua de consume humano South Africa South African National Standard SANS241:2011 Drinking-water Republic of Korea Management of Drinking-water Act 2008 Sri Lanka Sri Lanka Standards for potable water - SLS 614, 198 Sudan Drinking-water Standard ICS 13.060.00 2002 Suriname Anteproyecto de Ley 2003 Sweden Livsmedelsverkets föreskrifter (SLVFS 2001:30) om dricksvatten Syrian Arab Republic Syrian Arab Republic - Drinking-water Quality Standards 1994 Switzerland Criterès d’appréciation pour l’eau de boisson: composition chimique; composition microbiologie. SCVA VD / Inspection des eaux. Juillet 2008 98 The United Republic of Tanzania TZS 789:2003 - Drinking (potable) water - Specification Thailand Notification of the Ministry of Industry, No. 322, B.E. 2521 (1978), issued under the Industrial Products Standards Act B.E. 2511 (1968) Tunisia Project of Tunisian Standard PTS 14.09 (1993) Turkey İnsani Tüketim Amaçli Sular Hakkinda Yönetmelik (Regulations on water for human consumption) 2005 Uganda Uganda Standard US 201:2008 Drinking (potable) water - Specification Ukraine Гигиенические требования к воде питьевой, предназначенной для потребления человеком (ГCанПиН 2.2.4-171-10) (Hygienic requirements for drinking-water intended for human consumption) (GCanPiN 2.2.4-171-10): 2008 United Arab Emirates The Water Quality Regulations (Fourth Edition) 2014. The Regulation and Supervision Bureau for the water, wastewater and electricity sector in the Emirate of Abu Dhabi. United Kingdom The Water Supply (Water Quality) Regulations 2000 (England and Wales) (Similar Regulations apply in Scotland and Northern Ireland) Uruguay Agua potable - Requisitos, Instituto Uruguayo de Normas Técnicas 833:2008 USA National Primary Drinking-water Regulations 2009 Venezuela Normas Sanitaias de Calidad del Agua potable 1998 99 Viet Nam Nườc cấp sinh hoạt - yêu cấu chất lượng TCVN 5502 : 2003 (Domestic supply water - Quality requirements) West Bank and Gaza Strip Palestine Standard 41 1997 Zambia ZS 190:2010, ICS 13.060.20 (Drinking-water Quality - Specification), Zambian Bureau of Standards 100 For more information, contact: Water, Sanitation, Hygiene and Health World Health Organization 20, Avenue Appia 1211 Geneva 27 Switzerland E-mail: gdwq@who.int http://www.who.int/water_sanitation_health/water-quality/en/

A global overview of national regulations and standards for drinking-water quality ii A global overview of national regulations and standards for drinking-water quality ISBN 978-92-4- 151376-0 © World Health Organization 2018 Some rights reserved. This work is available under the Creative Commons Attribution- NonCommercial-ShareAlike 3.0 IGO licence (CC BY-NC-SA 3.0 IGO; https://creativecommons.org/licenses/by-nc-sa/3.0/igo). Under the terms of this licence, you may copy, redistribute and adapt the work for non- commercial purposes, provided the work is appropriately cited, as indicated below. In any use of this work, there should be no suggestion that WHO endorses any specific organization, products or services. The use of the WHO logo is not permitted. If you adapt the work, then you must license your work under the same or equivalent Creative Commons licence. 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Third-party materials. If you wish to reuse material from this work that is attributed to a third party, such as tables, figures or images, it is your responsibility to determine whether permission is needed for that reuse and to obtain permission from the copyright holder. The risk of claims resulting from infringement of any third-party-owned component in the work rests solely with the user. General disclaimers. The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of WHO concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Dotted and dashed lines on maps represent approximate border lines for which there may not yet be full agreement. The mention of specific companies or of certain manufacturers’ products does not imply that they are endorsed or recommended by WHO in preference to others of a similar nature that are not mentioned. Errors and omissions excepted, the names of proprietary products are distinguished by initial capital letters. All reasonable precautions have been taken by WHO to verify the information contained in this publication. However, the published material is being distributed without warranty of any kind, either expressed or implied. The responsibility for the interpretation and use of the material lies with the reader. In no event shall WHO be liable for damages arising from its use. iii Contents Abbreviations and acronyms ........................................................................................... iv Role of the WHO Guidelines for Drinking-water Quality ............................................... 1 Inorganic parameters ........................................................................................................ 7 Organic parameters ......................................................................................................... 19 Parameters relating to acceptability, taste and odour and appearance ........................... 64 Radiological parameters ................................................................................................. 77 Microbiological parameters ............................................................................................ 80 Additional parameters..................................................................................................... 84 Conclusion ...................................................................................................................... 88 References and source documentation ........................................................................... 89 Box 1. Guidance levels, guideline values, and health-based values ................................. 1 Box 2. Provisional guideline values .................................................................................. 2 Figure 1: Countries and territories represented in the survey ........................................... 3 iv Abbreviations and acronyms Bq/l Becquerel per litre BSS Basic Safety Standards cfu colony forming units EU European Union Euratom European Atomic Energy Community GDWQ Guidelines for Drinking-water Quality GL Guidance level GV Guideline value HBV health-based value ICRP International Commission on Radiological Protection μg/l micrograms per litre mg/l milligrams per litre mSv/year milli Sieverts per year NTU Nephelometric turbidity unit PAHO Pan American Health Organization pCi/l pico Curie per litre RegNet WHO International Network of Drinking-water Regulators TCU true colour unit WHO World Health Organization WHOPES WHO Pesticide Evaluation Scheme 1 Role of the WHO Guidelines for Drinking-water Quality The Guidelines for Drinking-water Quality (GDWQ) are one of the longest-standing normative publications of the World Health Organization (WHO), with the first edition published in 1958. The GDWQ are an international reference point for the establishment of national or regional regulations and standards for water safety. They are addressed to water and health regulators, policy-makers and their advisors, mainly to assist them in the development of national standards. The GDWQ are also used by many others as a source of information on water quality and health and on effective management approaches. The GDWQ include an assessment of the health risks presented by the various microbial, chemical, radiological and physical contaminants that may be present in drinking-water. Where applicable, they derive maximum concentration guideline values for these hazardous constituents. Through a Framework for Safe Drinking Water, the GDWQ support the development of health-based targets, implementation of preventive risk management strategies (through water safety planning), and independent surveillance. Health-based water quality targets define drinking-water that does not represent any significant risk to health, generally over a lifetime of consumption. These numeric targets include ‘guidance levels’ (GL), ‘guideline values’ (GV) and 'health-based values' (HBV) for constituents in drinking-water or indicators of water quality (Box 1). Box 1. Guidance levels, guideline values, and health-based values The term ‘guidance levels’ is used for radiological parameters, while ‘guideline values’ or ‘health-based values’ is used for all other parameters. Generally, health-based values have been established for some chemicals in the GDWQ, rather than a formal guideline value, in order to provide guidance to Member States when there is reason for local concern. Establishing a formal guideline value for such substances may encourage Member States to incorporate a value into their national standards when this may be unnecessary. In the case of manganese, a health-based value was established rather than a guideline value as manganese is not of health concern at levels normally causing acceptability problems in drinking-water (e.g. staining of laundry). However, there are circumstances in which manganese can remain in solution at concentrations of health concern in some acidic or anaerobic waters, particularly groundwater. It may therefore be appropriate to incorporate manganese in national standards under these circumstances and to consider both aesthetic as well as health aspects when confirming the acceptability of drinking-water. 2 In addition, a number of provisional guideline values have been established based on the practical level of treatment performance or analytical achievability (Box 2). In these cases, the guideline value is higher than the calculated health-based value. Recognizing the benefits of a risk management approach, the GDWQ are not promoted as mandatory international standards, but as guidance that should be adapted to the specific circumstances, needs and resources of countries. Therefore, national or regional drinking-water quality regulations should only include a subset of the values included in the GDWQ and may have different parameter limits than what is specified in the GDWQ. Many countries use the GDWQ directly or indirectly in setting national drinking-water quality standards. To better understand the extent to which the GDWQ are used and reflected in these standards, a global review of various country regulations and policies was conducted. This report summarizes information from 104 countries and territories on values specified in national drinking-water quality standards for aesthetic, chemical, microbiological and radiological parameters. The aim of the report is to enable regulators and other key stakeholders to access and compare data when setting or revising national drinking-water quality standards, although comparison should be approached with caution. The report is not intended to provide guidance on selecting appropriate parameters and parameter limits for drinking-water quality standards. The separate publication, Developing Drinking-water Quality Regulations and Standards (WHO, in press) should be consulted for such guidance. Box 2. Provisional guideline values For several chemical parameters, the GDWQ suggest guidelines values which may be provisional for the following reasons:  A: provisional guideline value set at the achievable quantification level;  P: provisional guideline value because of uncertainties in the health database;  T: provisional guideline value set at the practical treatment level); and  D: provisional guideline value set considering possible health effects and the need to maintain adequate disinfection. Adequate disinfection of drinking-water remains paramount. For some chemicals, GVs are designated with a “C”. This indicates that the concentration of the substance at or below the guideline value may affect the appearance, taste or odour of the water, which may lead to consumer complaints. 3 Data sources and methods The data reviewed in the report were obtained from members of the WHO International Network of Drinking-water Regulators (RegNet)1, WHO regional and country office contacts, through internet searches or purchased from the relevant standards organizations. Data were collected for 104 countries and territories (Figure 1) up to 2015, and were reviewed and validated. The data validation entailed an online public review, as well as review by WHO regional and country office contacts, and RegNet members, who were asked to clarify inconsistencies and provide data updates wherever relevant. Figure 1: Countries and territories represented in the survey These countries and territories have a total population of approximately 6.5 billion people, representing approximately 89 % of the world population2. Countries that are members of the European Union (EU) are subject to the requirements of its Drinking-water Directive and European Atomic Energy Community (Euratom) which specifies radionuclide requirements. However, all these countries have their own regulations, some of which differ from the 1 Information about RegNet can be found at the following link: http://www.who.int/water_sanitation_health/water-quality/regulation/regnet/en/ 2 Based on mid-year population estimates for 2017: United Nations, Department of Economic and Social Affairs, Population Division (2017). World Population Prospects: The 2017 Revision. Wallchart 4 Directive with more stringent requirements or include additional parameters. In addition, it is understood that the following countries and territories use the standards specified in the GDWQ without currently publishing separate documentation listing regulatory parameters and values at the time that data for this report were collected: Burkina Faso, Kiribati, Kuwait, Mali, Nauru, Senegal, Solomon Islands, Tonga and Tuvalu. Countries and territories specify parameter values for drinking-water quality in a variety of formats; regulations, standards, specifications, laws, decrees, requirements and norms. For the purposes of this report these are all referred to as standards. The drinking-water quality standards specified by countries and territories for inorganic chemicals, organic chemicals, aesthetic and microbiological parameters were compared to the GV or HBV; and radiological parameters were compared to the GL of the fourth edition of the GDWQ (WHO, 2011)3. This report does not include detailed background information on the parameters, including derivation and adaptation of guideline values and appropriate risk management strategies; the report should be read in conjunction with the GDWQ to provide this information. The report also does not include the extent and effectiveness of compliance monitoring by national regulatory authorities against national standards, including information on how many samples are required or taken for each parameter; or whether drinking-water quality in each country and territory meets the values specified. Documentation and the report According to the documentation reviewed, the oldest specifications of values for drinking- water in current use date back to 1978. Fourteen countries and territories’ values, (42 including the members of the European Union (EU) through the European Drinking-water Directive) date to the 1990s. However, many EU Member States have implemented the Directive through more recent documentation but these have not been included in the survey because they differ little in requirements from the original Directive. The other 62 countries and territories have produced documentation in the year 2000 and later. As countries and territories often review their legislation and values, these findings are constantly subject to change. 3 The most recent edition of the GDWQ is the fourth edition, first addendum published in 2017. For the first addendum, risk assessments for the following parameters have been revised, resulting in updated guideline or health-based values: barium, bentazone, diquat and MCPA. As the first addendum was published after the cut-off date for the review and further, as countries have had little time to consider the first addendum in their national standards, an analysis against these updated values has not been included in this document. Information on the changes made in the first addendum to the fourth edition of the GDWQ can be found at the following link: http://www.who.int/water_sanitation_health/publications/gdwq4-1st-addendum/en/ 5 Thirty-seven countries and territories directly reference the GDWQ in their standards, although this number is likely to be higher because the full documentation was not available in all cases. Botswana and Pakistan list the WHO GV alongside their values. Although the GDWQ encourage countries and territories to set their own water-quality standards to ensure they are locally relevant in terms of parameters included, limits, etc., none of the documentation received includes a full explanation on why parameters are included and how countries and territories derived their values, including where they differ from the WHO GV. However, this is now becoming more readily available in separate documentation such as that produced by Health Canada. Others more generally reference WHO and other countries and territories’ values, such as those of the European Union, the United States of America, Nigeria and South Africa. Some countries and territories’ standards also reference the analytical method required. In some cases the names of the members of expert committees who drew up the values are listed. Some countries and territories include in their standards details of the likely origin of parameters and their associated risk. This may help the understanding of those who have to control and analyze drinking-water quality. Examples are Australia, the Dominican Republic, Fiji, India, New Zealand, Nigeria, Pakistan, the Philippines, South Africa, Uruguay and the USA. Other countries and territories may provide similar information in separate documentation or consider the information included in the GDWQ sufficient. In addition to setting values for specific parameters, many countries and territories’ documentation includes a general statement along the lines of: “water intended for human consumption should: not contain concentrations of compounds which could, either alone or in combination with other compounds, be harmful to human health; and not contain any micro- organisms and parasites in such a number that could be harmful to human health”. For the purposes of this report, all values for chemical parameters have been converted to mg/l. The values used in this report are the highest listed by countries and territories in their standards for normal (non-emergency or severe weather-affected) water supplies. Not all the values countries and territories have listed are mandatory; some are advisory, for guidance or occasionally described as operational. This applies particularly to the aesthetic and other parameters. The GDWQ suggest values with a wide margin of safety, and countries and territories are advised to adapt their drinking-water quality standards to local conditions and circumstances. 6 For clarity and convenience this report has adopted the terms “higher” or “above” for values greater than those specified in the GDWQ and “lower” or “below” for values less than those specified in the GDWQ. Countries and territories may have good reasons to specify a value more, or less stringent than WHO based on an overall risk-benefit strategy to protect public health, whereby scarce resources directed to provide greatest public health benefits. In addition, differences in the number of parameters specified by countries and territories are to be expected, according to the relevance of the parameters to the countries and territories concerned. A list of source documentation used in this survey is provided at the end of the report. 7 Inorganic parameters The 4th edition of the GDWQ includes GVs or HBVs for 24 inorganic parameters. All 104 countries and territories specify values for copper, lead and nitrate, and all but one specify values for manganese. The least specified inorganic parameters were: beryllium (12 out 104 countries); glyphosate (11); and uranium (17). All the median values equalled or were below the GV except for cadmium (GV 0.003 mg/l, median 0.005 mg/l). Antimony WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 76 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 13 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 62 Maximum value set 0.05 mg/l Minimum value set 0.003 mg/l Median value 0.005 mg/l The majority of countries and territories (62/76) set a value for antimony below the GV, with 50 countries and territories setting 0.005 mg/l. Arsenic WHO Guideline value 0.01 mg/l (provisional A, T) Number of countries and territories setting a regulatory / guideline value 102 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 22 Number of countries and territories setting the WHO Guideline 79 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.5 mg/l Minimum value set 0.007 mg/l Median value 0.01 mg/l 8 Arsenic is one of the parameters with a value set by most countries and territories (102/104). The majority of countries (79/102) specified the provisional GV; only one country set a value below the provisional GV. Barium WHO Guideline value 0.7 mg/l4 Number of countries and territories setting a regulatory / guideline value 52 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 11 Number of countries and territories setting the WHO Guideline 35 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 6 Maximum value set 2.0 mg/l Minimum value set 0.1 mg/l Median value 0.7 mg/l The majority (35/52) of those countries and territories setting a value for barium specified the GV. Beryllium WHO Guideline value None specified WHO Health-based value 0.012 mg/l Number of countries and territories setting a regulatory / guideline value 12 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Health-based value 1 Number of countries and territories setting the WHO Health-based value 0 Number of countries and territories setting a regulatory / guideline value less than WHO Health-based value 11 Maximum value set 0.06 mg/l Minimum value set 0.0002 mg/l Median value 0.004 mg/l Beryllium is one of the least specified parameters; with only 12 out of the 104 countries and territories surveyed setting a value. 4 The GV has been increased to 1.3 mg/l in the first addendum to the 4th edition of GDWQ (WHO, 2017), which is available here: http://apps.who.int/iris/bitstream/10665/254637/1/9789241549950-eng.pdf?ua=1 9 Boron WHO Guideline value 2.4 mg/l Number of countries and territories setting a regulatory / guideline value 73 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 1 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 70 Maximum value set 5 mg/l Minimum value set 0.2 mg/l Median value 1 mg/l No country set the revised GV for boron in the 4th edition of the GDWQ (WHO, 2011); most countries and territories had based their value on the previous provisional GV of 0.5 mg/l. Bromate WHO Guideline value 0.01 mg/l (provisional A,T) Number of countries and territories setting a regulatory / guideline value 60 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 8 Number of countries and territories setting the WHO Guideline 51 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.025 mg/l Minimum value set 0.005 mg/l Median value 0.01 mg/l Most countries and territories specified a value for bromate at or close to the provisional GV. 10 Cadmium WHO Guideline value 0.003 mg/l Number of countries and territories setting a regulatory / guideline value 101 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 59 Number of countries and territories setting the WHO Guideline 38 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 4 Maximum value set 0.05 mg/l Minimum value set 0.001 mg/l Median value 0.005 mg/l Cadmium is the inorganic parameter for which the most countries and territories specified a higher value than the GV, as demonstrated by the median value. Only four countries and territories specified a value below the GV. Chlorate WHO Guideline value 0.7 mg/l (provisional D) Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 10 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 3 Maximum value set 1.0 mg/l Minimum value set 0.05 mg/l Median value 0.7 mg/l Only 16 countries and territories set a value for chlorate. On these, 10 set the provisional GV of 0.7 mg/L. 11 Chlorine WHO Guideline value*(C) 5.0 mg/l (as free chlorine) Number of countries and territories setting a regulatory / guideline value 66 Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 13 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 53 Maximum value set 5.0 mg/l Minimum value set 0.1 mg/l Median value 0.9 mg/l *It is possible to reduce the concentration of chlorine effectively to zero (<0.1 mg/l) by reduction; however, it is normal practice to supply water with a chlorine dioxide residual of a few tenths of a milligram per litre to provide some protection against microbial regrowth during distribution. Chlorine is the inorganic parameter with the largest range between minimum and maximum. No country had a value above the GV. Thirty two countries and territories specified a level below 1 mg/l. Eleven countries and territories specified the GV. Some countries and territories set a range, specifying minimum and maximum levels. It was not always clear if the set value referred to free or total chlorine. Chlorite WHO Guideline value 0.7 mg/l (provisional D) Number of countries and territories setting a regulatory / guideline value 28 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 6 Number of countries and territories setting the WHO Guideline 12 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 10 Maximum value set 1.0 mg/l Minimum value set 0.05 mg/l Median value 0.7 mg/l Twenty eight countries and territories set a value for chlorite, and of these, 12 specified the GV. 12 Chromium (total) WHO Guideline value 0.05 mg/l (provisional P) Number of countries and territories setting a regulatory / guideline value 99 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 94 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.5 mg/l Minimum value set 0.04 mg/l Median value 0.05 mg/l Most countries and territories set a value for total chromium, and the great majority set the provisional GV. Copper WHO Guideline value* 2.0 mg/l Number of countries and territories setting a regulatory / guideline value 104 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 51 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 51 Maximum value set 3.0 mg/l Minimum value set 0.05 mg/l Median value 1.5 mg/l *The GDWQ also notes that copper causes aesthetic issues including staining of laundry at concentrations above 1 mg/l Copper is one of only three inorganic parameters with a value set by all the countries and territories in the survey. The majority specified the GV, or specified lower values. Only two countries set values above the GV. 13 Cyanide WHO Guideline value No value established in fourth edition, previously 0.07 mg/l* WHO Health-based value 0.5 mg/l (rounded value, for short-term exposure) Number of countries and territories setting a regulatory / guideline value 101 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than the WHO health-based value 11 Number of countries and territories setting the previous WHO health-based value 30 Number of countries and territories setting a regulatory / guideline value less than the previous WHO health-based value 60 Maximum value set 0.6 mg/l Minimum value set 0.01 mg/l Median value 0.05 mg/l *The GV was changed to a HBV in the 4th edition of the GDWQ. The majority of countries and territories (101/104) set a value for this parameter, and over half specified values below the GV. Fluoride WHO Guideline value 1.5 mg/l Number of countries and territories setting a regulatory / guideline value 102 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 8 Number of countries and territories setting the WHO Guideline 77 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 17 Maximum value set 4.0 mg/l Minimum value set 0.6 mg/l Median value 1.5 mg/l All but two countries specified a value for this parameter, and the majority set the GV. Many specified a lower value for higher water temperatures. In some cases where a low value was set, a higher value was allowed under certain circumstances. 14 Glyphosate WHO Guideline value None specified WHO health-based value 0.9 mg/l Number of countries and territories setting a regulatory / guideline value 11 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Health-based value 1 Number of countries and territories setting the WHO Health-based value 0 Number of countries and territories setting a regulatory / guideline value less than WHO Health-based value 10 Maximum value set 1 mg/l Minimum value set 0.01 mg/l Median value 0.7 mg/l The GDWQ link together glyphosate and its major metabolite aminomethylphosphonic acid (AMPA). Because of their low toxicity, the health-based value derived for AMPA alone or in combination with glyphosate is orders of magnitude higher than concentrations of glyphosate or AMPA normally found in drinking-water. Under usual conditions, therefore, the presence of glyphosate and AMPA in drinking-water does not represent a hazard to human health. For this reason, the establishment of a formal guideline value for glyphosate and AMPA is not deemed necessary. Glyphosate is one of the least specified parameters; with only 11 out of the 104 countries and territories setting a value. No country or territory specified a value for AMPA. Lead WHO Guideline value 0.01 mg/l (provisional; A, T) Number of countries and territories setting a regulatory / guideline value 104 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 19 Number of countries and territories setting the WHO Guideline 84 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.1 mg/l Minimum value set 0.005 mg/l Median value 0.01 mg/l Lead is one of only three inorganic parameters with a value specified by all countries and territories in this survey. The majority set the GV, while some countries and territories allowed 15 time for the 0.01 mg/l standard to apply. Of the countries and territories that set a value above the GDWQ, most specified 0.05 mg/l. Manganese WHO Guideline value No value established in the fourth edition, previously 0.4 mg/l WHO Health-based value (4th edition)* 0.4 mg/l Number of countries and territories setting a regulatory / guideline value 103 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than the previous WHO Guideline 19 Number of countries and territories setting the previous WHO Guideline 11 Number of countries and territories setting a regulatory / guideline value less than the previous WHO Guideline 73 Maximum value set 0.5 mg/l Minimum value set 0.05 mg/l Median value 0.1 mg/l *The GV was changed to a HBV in the 4th edition of the GDWQ, recognizing that manganese is not of health concern at levels normally causing acceptability problems in drinking-water. Manganese can cause aesthetic issues, including taste impacts and staining of laundry at concentrations above 0.1 mg/l. However, there are circumstances in which manganese can remain in solution at concentrations of health concern in some acidic or anaerobic waters, particularly groundwaters. Therefore, aesthetic as well as health aspects should be considered in the establishment of standards and confirming the acceptability of drinking-water. All countries and territories in the survey set a value for manganese with the exception of one. The majority set a value below the previous GV. Some countries and territories listed the parameter as aesthetic, some as inorganic, and some as both. Mercury WHO Guideline value 0.006 mg/l Number of countries and territories setting a regulatory / guideline value 100 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 4 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 95 Maximum value set 0.007 mg/l Minimum value set 0.0005 mg/l Median value 0.001 mg/l 16 The majority of countries and territories (100/104) set a value for this parameter. Only four countries specified the GV; the most specified values below the GV. Molybdenum WHO Guideline value 0.07 mg/l Number of countries and territories setting a regulatory / guideline value 26 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 22 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.25 mg/l Minimum value set 0.05 mg/l Median value 0.07 mg/l The majority (22/26) of the countries and territories setting a value for molybdenum specified the GV. Nickel WHO Guideline value 0.07 mg/l Number of countries and territories setting a regulatory / guideline value 82 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 7 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 72 Maximum value set 0.1 mg/l Minimum value set 0.01 mg/l Median value 0.02 mg/l Most countries and territories specifying a value for nickel set it below the GV, at 0.02 mg/l. 17 Nitrate WHO Guideline value 50 mg/l* (as NO3-) Number of countries and territories setting a regulatory / guideline value 104 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 69 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 33 Maximum value set 75 mg/l (as NO3-) Minimum value set 40 mg/l (as NO3-) Median value 50 mg/l (as NO3-) *The GDWQ also include a value for combined nitrate plus nitrite as: The sum of the ratios of the concentrations as reported or detected in the sample of each to its guideline value should not exceed 1. Nitrate is one of only three inorganic parameters with a value set by all countries and territories in the survey. Many quoted their value as 10 mg/l (as N) which has been converted to 45 mg/l (as NO3 -) for the purposes of this report but counted as being at the GV. Several countries and territories including the European Union countries included a formula that reduces the nitrate value as the nitrite level increases. Nitrite WHO Guideline value 3 mg/l* (as NO2-) Number of countries and territories setting a regulatory / guideline value 96 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 39 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 55 Maximum value set 3.3 mg/l (as NO2-) Minimum value set 0.003 mg/l (as NO2-) Median value 0.5 mg/l (as NO2-) Median value 50 mg/l (as NO3-) *The GDWQ also include a value for combined nitrate plus nitrite as: The sum of the ratios of the concentrations as reported or detected in the sample of each to its guideline value should not exceed 1. Many countries and territories’ values for nitrite have been based on older WHO guidance. Only two countries had values above the revised GV. Thirty-nine countries and territories specified the revised GV (or its equivalent as mg N/l). Several countries and territories 18 including the European Union countries included a formula that reduces the nitrate value as the nitrite level increases. Selenium WHO Guideline value 0.04 mg/l (provisional, P) Number of countries and territories setting a regulatory / guideline value 96 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 1 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 93 Maximum value set 0.05 mg/l Minimum value set 0.007 mg/l Median value 0.01 mg/l Only one country specified the new provisional GV of 0.04 mg/l; almost all others specified the previous value of 0.01 mg/l. Uranium WHO Guideline value 0.03 mg/l (provisional P) Number of countries and territories setting a regulatory / guideline value 17 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 17 Maximum value set 0.1 mg/l Minimum value set 0.002 mg/l Median value 0.015 mg/l Uranium is one of the least specified parameters; with only 17 out of the 104 countries and territories setting a value. The majority specified a value based on the previous GV, with no country specifying the latest. 19 Organic parameters The 4th edition of the GDWQ includes GVs or HBVs for 89 organic parameters. The most specified organic parameters are: aldrin and dieldrin (71 out of 104 countries and territories); benzene (77); tetrachloroethene (71); and 1,2 dichloroethane (67). Among the least specified values are: 2-phenylphenol (1); fenitrothion (2); nitrobenzene (3); and N-nitrosodimethylamine (NDMA, 3). No country or territory specified a value for cyanuric acid, sodium dichloroisocyanurate or hydroxyatrazine. Seven countries and territories did not specify values for any inorganic parameters, while some included notes with general requirements for low levels of pesticides. For the organic parameters that had specifications, all but four had median values equal to or below the GV. The exceptions were: cyanazine (GV 0.0006 mg/l, median 0.0007 mg/l), but only specified by five countries and territories; dibromoacetonitrile (GV 0.07 mg/l, median 0.0775), specified by 16 countries and territories; dichloroacetonitrile (GV 0.02 mg/l, median 0.06 mg/l), specified by 17 countries and territories; and vinyl chloride (GV 0.0003 mg/l, median 0.0005 mg/l), specified by 60 countries and territories. Forty-six countries and territories do not specify values for most individual pesticides other than aldrin and dieldrin, heptachlor and heptachlor epoxide. Instead, they include a blanket statement that the value for all individual pesticides is 0.0001 mg/l, and for total pesticides 0.0005 mg/l (where “total pesticides” is defined as the sum of all individual pesticides detected and quantified in the monitoring procedure), or similar requirement. Where a country or territory does not specify a value for an individual parameter in its standards, it is not included in the tables below. Acrylamide WHO Guideline value 0.0005 mg/l Number of countries and territories setting a regulatory / guideline value 56 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 20 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 36 Maximum value set 0.0005 mg/l Minimum value set 0.0001 mg/l Median value 0.0001 mg/l 20 Almost half of the countries and territories (56/104) set a value for acrylamide. No country set a value greater than the GV; the majority set 0.0001 mg/l. Alachlor WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 24 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 19 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 4 Maximum value set 0.15 mg/l Minimum value set 0.002 mg/l Median value 0.02 mg/l Most countries and territories (19/24) set the GV; and only one set a higher value. Aldicarb WHO Guideline value 0.01 mg/l Number of countries and territories setting a regulatory / guideline value 22 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 17 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 5 Maximum value set 0.01 mg/l Minimum value set 0.003 mg/l Median value 0.01 mg/l Only five out of 22 countries and territories set values that differed from the GV. 21 Aldrin and Dieldrin WHO Guideline value 0.00003 mg/l Number of countries and territories setting a regulatory / guideline value 71 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 6 Number of countries and territories setting the WHO Guideline 62 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 3 Maximum value set 0.001 mg/l Minimum value set 0.00001 mg/l (0) Median value 0.00003 mg/l Most countries and territories (62/71) specified the GV, and only three set values that were lower. Atrazine and its chloro-s-triazine metabolites WHO Guideline value 0.1 mg/l Number of countries and territories setting a regulatory / guideline value 28 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 27 Maximum value set 0.5 mg/l Minimum value set 0.0015 mg/l Median value 0.002 mg/l There was wide deviation from the GV in the values set for this parameter. Only one country set a value above the GV, all the other countries and territories were well below. 22 Bentazone WHO Guideline value None specified WHO health-based value 0.3 mg/l5 Number of countries and territories setting a regulatory / guideline value 11 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Health-based value 2 Number of countries and territories setting the WHO Health-based value 4 Number of countries and territories setting a regulatory / guideline value less than WHO Health-based value 5 Maximum value set 0.4 mg/l Minimum value set 0.03 mg/l Median value 0.03 mg/l Only 11 countries and territories set a value for bentazone, and the majority set below the HBV of 0.3 mg/L specified in the 4th edition of the GDWQ (WHO, 2011). Benzene WHO Guideline value 0.01 mg/l Number of countries and territories setting a regulatory / guideline value 77 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 31 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 45 Maximum value set 0.03 mg/l Minimum value set 0.001 mg/l Median value 0.005 mg/l Benzene is the most specified organic parameter among the 104 countries and territories surveyed. The majority specified values below the GV of 0.01 mg/L, and only one country specified a higher value. 5 The HBV has been increased to 0.5 mg/l in the first addendum to the 4th edition of GDWQ (WHO, 2017), which is available here: http://apps.who.int/iris/bitstream/10665/254637/1/9789241549950-eng.pdf?ua=1 23 Benzo[a]pyrene WHO Guideline value 0.0007 mg/l Number of countries and territories setting a regulatory / guideline value 65 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 15 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 50 Maximum value set 0.0007 mg/l Minimum value set 0.000005 mg/l Median value 0.00001 mg/l Where countries and territories also had a value for polynuclear aromatic hydrocarbons (PAH; see additional parameters), this parameter was usually quoted separately. The majority of countries and territories set a value below the GV, and no country set a value higher than the GV. Bromodichloromethane WHO Guideline value 0.06 mg/l* Number of countries and territories setting a regulatory / guideline value 29 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 22 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 7 Maximum value set 0.06 mg/l Minimum value set 0.015 mg/l Median value 0.06 mg/l *See total trihalomethanes (THMs) for information on how to account for additive toxicity with other individual THM compounds Of the 29 countries and territories specifying a value for this parameter, the majority (22) specified the GV. Some countries and territories which did not specify a value for this parameter included it in their value for total trihalomethanes. 24 Bromoform WHO Guideline value 0.1 mg/l* Number of countries and territories setting a regulatory / guideline value 23 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 21 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.1 mg/l Minimum value set 0.075mg/l Median value 0.1 mg/l *See total trihalomethanes (THMs) for information on how to account for additive toxicity with other individual THM compounds All but two of the countries and territories specifying a value for this parameter used the GV. Some countries and territories which did not specify a value for this parameter included it in their value for total trihalomethanes. Carbofuran WHO Guideline value 0.007 mg/l Number of countries and territories setting a regulatory / guideline value 26 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 7 Number of countries and territories setting the WHO Guideline 10 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 9 Maximum value set 0.09 mg/l Minimum value set 0.0035 mg/l Median value 0.007 mg/l Twenty-six countries and territories specified a value for carbofuran, with the majority (16) setting values greater or less than the GV. 25 Carbon tetrachloride WHO Guideline value 0.004 mg/l Number of countries and territories setting a regulatory / guideline value 34 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 8 Number of countries and territories setting the WHO Guideline 10 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 16 Maximum value set 0.005 mg/l Minimum value set 0.0013 mg/l Median value 0.004 mg/l Twenty-four of the 34 countries and territories specifying a value for this parameter differed from the GV. Eight countries and territories specified 0.005 mg/l. Chloral hydrate (trichloracetaldehyde) WHO Health-based value 0.1 mg/l (rounded figure) Number of countries and territories setting a regulatory / guideline value 11 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO health-based value 0 Number of countries and territories setting the WHO health-based value 2 Number of countries and territories setting a regulatory / guideline value less than WHO health-based value 9 Maximum value set 0.1 mg/l Minimum value set 0.01 mg/l Median value 0.01 mg/l Only 11 countries and territories specified a value for chloral hydrate, and nine of these set values below the HBV. 26 Chlordane WHO Guideline value 0.0002 mg/l Number of countries and territories setting a regulatory / guideline value 33 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 9 Number of countries and territories setting the WHO Guideline 23 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.003 mg/l Minimum value set 0.00015 mg/l Median value 0.0002 mg/l The majority of countries and territories specifying a value for chlordane set the GV (23/33), and only one specified a lower value. Chloroform WHO Guideline value 0.3 mg/l* Number of countries and territories setting a regulatory / guideline value 36 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 6 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 29 Maximum value set 0.4 mg/l Minimum value set 0.03 mg/l Median value 0.2 mg/l *See total trihalomethanes (THMs) for information on how to account for additive toxicity with other individual THM compounds The majority of countries and territories specifying a value for this parameter set a value below the GV, most specifying 0.2 mg/l. Some countries and territories did not specify a value for this parameter but included it in their value for total trihalomethanes. 27 Chlorotoluron WHO Guideline value 0.03 mg/l Number of countries and territories setting a regulatory / guideline value 12 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 10 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.04 mg/l Minimum value set 0.02 mg/l Median value 0.03 mg/l The majority of countries and territories specifying a value for chlorotoluron set the GV (10/12). Chlorpyrifos WHO Guideline value 0.03 mg/l Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 12 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.09 mg/l Minimum value set 0.01 mg/l Median value 0.03 mg/l The majority of countries and territories specifying a value for this parameter set the GV (12/16). 28 Cyanazine WHO Guideline value 0.0006 mg/l Number of countries and territories setting a regulatory / guideline value 5 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 2 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.01 mg/l Minimum value set 0.0006 mg/l Median value 0.0007 mg/l Only five countries and territories specified a value for cyanazine, and none set a value below the GV. Cyanogen Chloride WHO Guideline value No value specified in fourth edition, previously 0.07 mg/l WHO Health-based value 0.6 mg/l (rounded value) Number of countries and territories setting a regulatory / guideline value 13 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than previous WHO Guideline 0 Number of countries and territories setting the previous WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than previous WHO Guideline 13 Maximum value set 0.07 mg/l Minimum value set 0.05 mg/l Median value 0.07 mg/l The 4th edition of the GDWQ specifies a HBV of 0.6 mg/l for cyanogen chloride, a change from the GV of 0.07 mg/l previously specified in the 3rd edition. All the thirteen countries and territories setting values for this parameter set values lower than the HBV. All countries and territories specified the former GV (0.07 mg/l) except one (0.005 mg/l). 29 Cyanuric Acid WHO Guideline value 40 mg/l Number of countries and territories setting a regulatory / guideline value 0 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 No country in the survey set a value for this parameter. 2,4-D (2,4-Dichlorophenoxyacetic Acid) WHO Guideline value 0.03 mg/l Number of countries and territories setting a regulatory / guideline value 42 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 9 Number of countries and territories setting the WHO Guideline 31 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.1 mg/l Minimum value set 0.01 mg/l Median value 0.03 mg/l The majority of countries and territories setting a value for this parameter designated the GV; only two set values less than the GV. 2,4-DB (2,4-Dichlorophenoxybutyric Acid) WHO Guideline value 0.09 mg/l Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 4 Number of countries and territories setting the WHO Guideline 11 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.1 mg/l Minimum value set 0.067 mg/l Median value 0.09 mg/l 30 Only 16 countries and territories designated a value for this parameter, with most setting the GV. Dichlorodiphenyltrichloroethane (DDT) and metabolites WHO Guideline value 0.001 mg/l Number of countries and territories setting a regulatory / guideline value 42 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 18 Number of countries and territories setting the WHO Guideline 24 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.05 mg/l Minimum value set 0.001 mg/l Median value 0.001 mg/l Forty-two countries and territories specified a value for DDT, with over half (24/42) setting the GV. Di(2-ethylhexyl)phthalate WHO Guideline value 0.008 mg/l Number of countries and territories setting a regulatory / guideline value 11 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 7 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 3 Maximum value set 0.009 mg/l Minimum value set 0.002 mg/l Median value 0.008 mg/l Eleven countries and territories designated a value for this parameter, and only one set a value greater than the GV. 31 Dibromoacetylnitrile WHO Guideline value 0.07 mg/l Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 9 Number of countries and territories setting the WHO Guideline 6 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.1 mg/l Minimum value set 0.01 mg/l Median value 0.0775 mg/l Only 16 countries and territories designated a value for this parameter, and only one set a value less than the GV. Dibromochloromethane WHO Guideline value 0.1 mg/l* Number of countries and territories setting a regulatory / guideline value 29 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 23 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 5 Maximum value set 0.15 mg/l Minimum value set 0.01 mg/l Median value 0.1 mg/l *See total trihalomethanes (THMs) for information on how to account for additive toxicity with other individual THM compounds Among the twenty-nine countries and territories designating a value for dibromochloromethane, the majority specified the GV, and only one set a greater value. 32 1,2-Dibromo-3-chloropropane WHO Guideline value 0.001 mg/l Number of countries and territories setting a regulatory / guideline value 21 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 16 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 3 Maximum value set 0.007 mg/l Minimum value set 0.0002 mg/l Median value 0.001 mg/l Only five out of 21 countries and territories set values that differed from the GV for 1,2- Dibromo-3-chloropropane. 1,2-Dibromoethane WHO Guideline value 0.0004 mg/l Number of countries and territories setting a regulatory / guideline value 8 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 7 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.0004 mg/l Minimum value set 0.00001 mg/l Median value 0.0004 mg/l Only eight countries and territories specified a value for this parameter, and the majority set the GV. 33 Dichloroacetic acid WHO Guideline value 0.05 mg/l (provisional, D) Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 14 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.05 mg/l Minimum value set 0.02 mg/l Median value 0.05 mg/l Of the 16 countries and territories specifying a value for dichloroacetic acid, only two did not specify the provisional GV. Dichloroacetonitrile WHO Guideline value 0.02 mg/l (provisional, P) Number of countries and territories setting a regulatory / guideline value 17 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 9 Number of countries and territories setting the WHO Guideline 7 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.09 mg/l Minimum value set 0.01 mg/l Median value 0.06 mg/l Seventeen countries and territories specified a value for dichloroacetonitrile, and of these, almost half (9/17) set values above the provisional GV. 34 1,2-Dichlorobenzene WHO Guideline value 1 mg/l (C)* Number of countries and territories setting a regulatory / guideline value 26 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 15 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 9 Maximum value set 1.5 mg/l Minimum value set 0.0005 mg/l Median value 1 mg/l *Concentrations at or below the health-based guideline value may affect the appearance, taste or odour of the water, leading to consumer complaints There was wide variation in values specified for this parameter according to whether countries and territories followed the WHO health-based GV or a value based on taste and odour thresholds. Some specified values for both. 1,4-Dichlorobenzene WHO Guideline value 0.3 mg/l (C)* Number of countries and territories setting a regulatory / guideline value 25 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 15 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 9 Maximum value set 0.4 mg/l Minimum value set 0.0004 mg/l Median value 0.3 mg/l *Concentrations at or below the health-based guideline value may affect the appearance, taste or odour of the water, leading to consumer complaints As with 1,2- Dichlorobenzene, countries and territories also specified health-based GVs or values based on taste and odour thresholds, and some specified values for both. 35 1,2-Dichloroethane WHO Guideline value 0.03 mg/l Number of countries and territories setting a regulatory / guideline value 67 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 18 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 47 Maximum value set 0.05 mg/l Minimum value set 0.003 mg/l Median value 0.003 mg/l Of the 67 countries and territories specifying a value for this parameter, 33specified the lowest value of 0.003 mg/l, and only 2 specified values greater than the GV. 1,1-Dichloroethene (Vinylidene chloride) WHO Guideline value No value established in the 4th edition, previously 0.03 mg/l WHO Health-based value 0.140 mg/l Number of countries and territories setting a regulatory / guideline value 30 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than the previous WHO Guideline 0 Number of countries and territories setting the previous WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than the previous WHO Guideline 30 Maximum value set 0.1 mg/l Minimum value set 0.0003 mg/l Median value 0.03 mg/l The 4th edition of the GDWQ specify a HBV of 140 μg/l (0.140 mg/l) for 1,1-dichloroethene, a change from the GV of 0.03 mg/l previously specified in the 3rd edition. All the thirty countries and territories setting values for this parameter set values less than the HBV. 36 1,2-Dichloroethene WHO Guideline value 0.05 mg/l Number of countries and territories setting a regulatory / guideline value 23 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 4 Number of countries and territories setting the WHO Guideline 17 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.1 mg/l Minimum value set 0.035 mg/l Median value 0.05 mg/l Of the 23 countries and territories setting a value for this parameter, the majority (17/23) did not differ from the GV. Dichloromethane WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 28 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 21 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 5 Maximum value set 0.05 mg/l Minimum value set 0.003 mg/l Median value 0.02 mg/l Of the 28 countries and territories setting a value for this parameter, the majority (17/23) did not differ from the GV. 37 1,2-Dichloropropane WHO Guideline value 0.04 mg/l (provisional P) Number of countries and territories setting a regulatory / guideline value 20 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 6 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 13 Maximum value set 0.05 mg/l Minimum value set 0.005 mg/l Median value 0.02 mg/l Twenty countries and territories set a value for this parameter, and the majority (13/20) specified values less than the GV. 1,3-Dichloropropene WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 14 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.1 mg/l Minimum value set 0.015 mg/l Median value 0.02 mg/l The majority of countries and territories (14/16) setting a value for 1,3-Dichloropropene specified the GV. 38 Dichlorprop WHO Guideline value 0.1 mg/l Number of countries and territories setting a regulatory / guideline value 19 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 18 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.1 mg/l Minimum value set 0.075 mg/l Median value 0.1 mg/l None of the 19 countries and territories specifying a value for dichlorprop set a value above the GV. Di(2-ethylhexyl)phthalate WHO Guideline value 0.008 mg/l Number of countries and territories setting a regulatory / guideline value 17 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 10 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 4 Maximum value set 0.1 mg/l Minimum value set 0.001 mg/l Median value 0.008 mg/l The majority of countries and territories (10/17) specified the GV for di(2- ethylhexyl)phthalateJapan of 0.1 mg/l. 39 Dimethoate WHO Guideline value 0.006 mg/l Number of countries and territories setting a regulatory / guideline value 12 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 9 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.08 mg/l Minimum value set 0.006 mg/l Median value 0.006 mg/l Only three countries out of 12 specified values above the GV for dimethoate, and none specified values below. 1,4-Dioxane WHO Guideline value 0.05 mg/l Number of countries and territories setting a regulatory / guideline value 5 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 5 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.05 mg/l Minimum value set 0.05 mg/l Median value 0.05 mg/l All five countries specifying a value for this parameter set the GV. 40 Diquat WHO Guideline value None WHO Health-based value 0.006 mg/l6 Number of countries and territories setting a regulatory / guideline value 7 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 7 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.07 mg/l Minimum value set 0.007 mg/l Median value 0.02 mg/l All seven countries and territories that specified a value for diquat set values above the HBV of 0.006 mg/L. Edetec Acid (EDTA) WHO Guideline value 0.6 mg/l Number of countries and territories setting a regulatory / guideline value 18 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 8 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 9 Maximum value set 0.7 mg/l Minimum value set 0.15 mg/l Median value 0.425 mg/l Of the eighteen countries and territories specifying a value for EDTA, only one set a value above the GV. 6 The HBV has been increased to 0.03 mg/l in the first addendum to the 4th edition of GDWQ (WHO, 2017), which is available here: http://apps.who.int/iris/bitstream/10665/254637/1/9789241549950-eng.pdf?ua=1 41 Endrin WHO Guideline value 0.0006 mg/l Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 4 Number of countries and territories setting the WHO Guideline 9 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 3 Maximum value set 0.002 mg/l Minimum value set 0.0001 mg/l Median value 0.0006 mg/l The majority (9/16) of countries and territories setting a value for endrin specified the GV. Endosulfan WHO Guideline value None WHO Health-based value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 9 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 3 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 4 Maximum value set 0.03 mg/l Minimum value set 0.00035 mg/l Median value 0.02 mg/l Nine countries and territories set a value for endosulfan. 42 Epichlorohydrin WHO Guideline value 0.0004 mg/l Number of countries and territories setting a regulatory / guideline value 54 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 16 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 35 Maximum value set 0.0005 mg/l Minimum value set 0.0001 mg/l Median value 0.0001 mg/l Over half of the countries and territories in the survey specified a value for this parameter, with the majority (35/54) setting a value below the GV of 0.0004 mg/L. Thirty-two countries and territories specified 0.0001 mg/l; and one country specified 0.0002 mg/l as a treatment standard only where epichlorohydrin is used in treatment. Ethylbenzene WHO Guideline value 0.3 mg/l (C)* Number of countries and territories setting a regulatory / guideline value 27 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 21 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 3 Maximum value set 0.7 mg/l Minimum value set 0.0024 mg/l Median value 0.3 mg/l *Concentrations at or below the health-based guideline value may affect the appearance, taste or odour of the water, leading to consumer complaints The majority (21/27) of countries and territories specified the GV for ethylbenzene. 43 Fenitrothion WHO Guideline value None WHO Health-based value 0.008 mg/l Number of countries and territories setting a regulatory / guideline value 2 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.04 mg/l Minimum value set 0.007 mg/l Median value 0.0235 mg/l Fenitrithion is one of the least specified organic parameters, with only two countries specifying a value. Fenoprop WHO Guideline value 0.009 mg/l Number of countries and territories setting a regulatory / guideline value 14 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 11 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.01 mg/l Minimum value set 0.006 mg/l Median value 0.009 mg/l Of the 14 countries and territories specifying a value for fenoprop, there is little variation from the GV of 0.009 mg/L 44 Heptachlor and Heptachlor Epoxide WHO Guideline value None specified WHO Health-based value 0.00003 mg/l Number of countries and territories setting a regulatory / guideline value 21 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO health-based value 5 Number of countries and territories setting the WHO health-based value 16 Number of countries and territories setting a regulatory / guideline value less than WHO health-based value 0 Maximum value set 0.0002 mg/l Minimum value set 0.00003 mg/l Median value 0.00003 mg/l Of the 21 countries and territories specifying a value for heptachlor and heptachlor epoxide, none set a value less than the HBV. Hexachlorobenzene WHO Guideline value None specified WHO Health-based value 0.001 mg/l Number of countries and territories setting a regulatory / guideline value 22 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO health-based value 0 Number of countries and territories setting the WHO health-based value 16 Number of countries and territories setting a regulatory / guideline value less than WHO health-based value 6 Maximum value set 0.001 mg/l Minimum value set 0.00001 mg/l Median value 0.001 mg/l The majority of countries and territories (16/22) specifying a value for hexachlorobenzene set the HBV, and none set values greater. 45 Hexachlorobutadiene WHO Guideline value 0.0006 mg/l Number of countries and territories setting a regulatory / guideline value 19 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 12 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 5 Maximum value set 0.0007 mg/l Minimum value set 0.0004 mg/l Median value 0.0006 mg/l The majority of countries and territories (12/19 ) specifying a value for hexachlorobutadiene set the GV. Hydroxyatrazine WHO Guideline value 0.2 mg/l Number of countries and territories setting a regulatory / guideline value 0 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 None of countries and territories in the survey specified a value for this parameter. 46 Isoproturon WHO Guideline value 0.009 mg/l Number of countries and territories setting a regulatory / guideline value 19 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 17 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.01 mg/l Minimum value set 0.007 mg/l Median value 0.009 mg/l There was little variation from the GV in the values specified for isoproturon, with only 2/19 countries and territories specifying the GV. Lindane WHO Guideline value 0.002 mg/l Number of countries and territories setting a regulatory / guideline value 44 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 7 Number of countries and territories setting the WHO Guideline 32 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 5 Maximum value set 0.01 mg/l Minimum value set GV 0.0002 mg/l Median value 0.002 mg/l Of the 44 countries and territories specifying a value for lindane, the majority set the GV. 47 MCPA (4-(2-Methyl-4-chlorophenoxy) acetic acid) WHO Guideline value 0.002 mg/l7 Number of countries and territories setting a regulatory / guideline value 22 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 19 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.1 mg/l Minimum value set 0.002 mg/l Median value 0.002 mg/l All countries and territories specifying a value for MCPA set the GV, with the exception of three that set values greater values. Mecoprop WHO Guideline value 0.01 mg/l Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 14 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.01 mg/l Minimum value set 0.001 mg/l Median value 0.01 mg/l Mecoprop was specified by 16 countries and territories, and only two did not specify the GV. 7 The guideline value has changed to 0.7 mg/l in the first addendum to the 4th edition of GDWQ, which can be found here: http://www.who.int/water_sanitation_health/publications/drinking-water-quality-guidelines-4- including-1st-addendum/en/ 48 Methoxychlor WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 38 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 8 Number of countries and territories setting the WHO Guideline 29 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.9 mg/l Minimum value set 0.015 mg/l Median value 0.02 mg/l Most countries and territories (29/38) specified the GV but there was considerable variation in the nine other values for this parameter. Methyl parathion WHO Guideline value None WHO Health-based value 0.009 mg/l Number of countries and territories setting a regulatory / guideline value 8 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 1 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 4 Maximum value set 0.1 mg/l Minimum value set 0.0003 mg/l Median value 0.008 mg/l Eight countries and territories set a value for methyl parathion, and only one of them specified the GV. 49 Metolachlor WHO Guideline value 0.01 mg/l Number of countries and territories setting a regulatory / guideline value 21 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 18 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.3 mg/l Minimum value set 0.007 mg/l Median value 0.01 mg/l All 21 of the countries and territories specifying a value for metolachlor specified the GV, with the exception of three countries. Microcystin-LR WHO Guideline value 0.001 mg/l (provisional, P) Number of countries and territories setting a regulatory / guideline value 14 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 12 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.0015 mg/l Minimum value set 0.001 mg/l Median value 0.001 mg/l Microcystin-LR was specified by 14 countries and territories, and of these, only two did not specify the provisional GV of 0.001 mg/L. 50 Molinate WHO Guideline value 0.006 mg/l Number of countries and territories setting a regulatory / guideline value 20 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 17 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.007 mg/l Minimum value set 0.004 mg/l Median value 0.006 mg/l Of the 20 countries and territories specifying a value for molinate, only three did not specify the GV. Monochloramine WHO Guideline value 3 mg/l Number of countries and territories setting a regulatory / guideline value 19 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 15 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 4 mg/l Minimum value set 2 mg/l Median value 3 mg/l Of the 19 countries and territories specifying a value for this parameter only four did not specify the GV. One country specified 3 mg/l post-treatment, but 0.05 mg/l in distribution. 51 Monochloroacetic Acid (Monochloroacetate) WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 7 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 6 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.2 mg/l Minimum value set 0.02 mg/l Median value 0.02 mg/l Only seven countries and territories specified a value for monochloroacetate, and almost all specified the GV. Nitrilotriacetic Acid WHO Guideline value 0.2 mg/l Number of countries and territories setting a regulatory / guideline value 18 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 16 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.4 mg/l Minimum value set 0.15 mg/l Median value 0.2 mg/l Of the 18 countries and territories specifying a value for this parameter only two did not specify the GV. 52 Nitrobenzene WHO Guideline value None WHO Health-based value 0.03 mg/l (short term) 0.008-0.063 mg/l (long term exposure, depending on end-point and approach used) Number of countries and territories setting a regulatory / guideline value 3 Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.2 mg/l Minimum value set 0.004 mg/l Median value 0.102 mg/l The GDWQ derive two HBVs for nitrobenzene; one for short- and the other for long-term exposure, based on the limited available information. Only three countries specified a value for this parameter. N-Nitrosodimethylamine (NDMA) WHO Guideline value 0.0001 mg/l Number of countries and territories setting a regulatory / guideline value 3 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 1 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.0001 mg/l Minimum value set 0.000012 mg/l Median value 0.00004 mg/l NDMA is among the least specified organic parameters, with only three countries and territories specifying a value. 53 Parathion WHO Guideline value None WHO Health-based value 0.01 mg/l Number of countries and territories setting a regulatory / guideline value 7 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 5 Number of countries and territories setting the WHO Guideline 1 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.05 mg/l Minimum value set 0.003 mg/l Median value 0.02 mg/l The majority of countries and territories setting values for this parameter (5/7) specified values above the HBV of 0.01 mg/L. Pendimethalin WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 20 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 1 Number of countries and territories setting the WHO Guideline 18 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.4 mg/l Minimum value set 0.015 mg/l Median value 0.02 mg/l Of the 20 countries and territories specifying a value for pendimethalin, only two did not specify the GV. 54 Pentachlorophenol (PCP) WHO Guideline value 0.009 mg/l Number of countries and territories setting a regulatory / guideline value 35 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 5 Number of countries and territories setting the WHO Guideline 23 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 7 Maximum value set 0.06 mg/l Minimum value set 0.0001 mg/l Median value 0.009 mg/l The majority of countries and territories specifying values for PCP specified the GV. Permethrin WHO Guideline value No value established in fourth edition, previously 0.3 mg/l WHO Health-based value* 0.3mg/l Number of countries and territories setting a regulatory / guideline value 17 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than the previous WHO Guideline 0 Number of countries and territories setting the previous WHO Guideline 3 Number of countries and territories setting a regulatory / guideline value less than the previous WHO Guideline 14 Maximum value set 0.3 mg/l Minimum value set 0.02 mg/l Median value 0.02 mg/l *The GV was changed to a HBV in the 4th edition of the GDWQ, recognizing that it is not recommended for direct addition to drinking-water as part of WHO’s policy to exclude the use of any pyrethroids for larviciding of mosquito vectors of human disease Permethrin was specified by 17 countries and territories. The majority specified values less than the HBV of 0.3 mg/L, with 13 countries and territories specifying 0.02 mg/l. 55 2-Phenylphenol and its sodium salt WHO Guideline value None WHO Health-based value 1 mg/l Number of countries and territories setting a regulatory / guideline value 1 Number of countries and territories setting a regulatory / guideline value greater than the previous WHO Guideline 1 Number of countries and territories setting the previous WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than the previous WHO Guideline 0 Maximum value set 1.4 mg/l Minimum value set 1.4 mg/l Median value 1.4 mg/l 2-Phenylphenol is among the least specified organic parameters; only one country set a value for this parameter. Pyriproxyfen WHO Guideline value* No value established in 4th edition, previously 0.3 mg/l Number of countries and territories setting a regulatory / guideline value 5 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than previous WHO Guideline 1 Number of countries and territories setting the previous WHO Guideline 4 Number of countries and territories setting a regulatory / guideline value less than previous WHO Guideline 0 Maximum value set 0.4 mg/l Minimum value set 0.3 mg/l Median value 0.3 mg/l *Under the WHO Pesticides Evaluation Scheme (WHOPES) the recommended dosage of pyriproxyfen in potable water in containers should not exceed 0.01mg/l. Pyroproxifen is a pesticide used for vector control in drinking-water sources and containers. While the 3rd edition of the GDWQ included a GV of 0.3 mg/l, the 4th edition of the GDWQ does not specify a value for pyriproxyfen as it is not considered appropriate to establish guideline values for vector control pesticides. However, it has been included here because a 56 GV was set in the 3rd edition, and five of the countries and territories retain a value for this parameter. Simazine WHO Guideline value 0.002 mg/l Number of countries and territories setting a regulatory / guideline value 24 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 4 Number of countries and territories setting the WHO Guideline 19 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.02 mg/l Minimum value set 0.0015 mg/l Median value 0.002 mg/l Simazine was specified by 24 countries and territories, with the majority specifying the GV. Sodium Dichloroisocyanurate WHO Guideline value 50 mg/l Number of countries and territories setting a regulatory / guideline value 0 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 No country set a value for this parameter. 57 Styrene WHO Guideline value 0.02 mg/l (C)* Number of countries and territories setting a regulatory / guideline value 24 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 5 Number of countries and territories setting the WHO Guideline 18 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 1 Maximum value set 0.1 mg/l Minimum value set 0.015 mg/l Median value 0.02 mg/l *Concentrations at or below the health-based guideline value may affect the appearance, taste or odour of the water, leading to consumer complaints Twenty-four of the 104 countries and territories surveyed specified a value for styrene, with the majority specifying the GV. Terbuthylazine WHO Guideline value 0.007 mg/l Number of countries and territories setting a regulatory / guideline value 7 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 5 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.01 mg/l Minimum value set 0.007 mg/l Median value 0.007 mg/l Seven countries and territories specified a value for terbuthylazine, and of these, five specified the GV. 58 Tetrachloroethene WHO Guideline value 0.04 mg/l Number of countries and territories setting a regulatory / guideline value 70 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 22 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 46 Maximum value set 0.05 mg/l Minimum value set 0.001 mg/l Median value 0.01 mg/l Tetrachloroethene is among the most specified organic parameters, and one of few parameters where the majority of countries and territories specifying a value set it below the GV. Trichloroacetic acid WHO Guideline value 0.2 mg/l Number of countries and territories setting a regulatory / guideline value 18 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting the WHO Guideline 10 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 8 Maximum value set 0.2 mg/l Minimum value set 0.02 mg/l Median value 0.2 mg/l Ten out of 18 countries and territories specifying a value for trichloroacetic acid specified the GV. 59 1,1,1-Trichloroethane WHO Guideline value None specified WHO Health-based value 2 mg/l Number of countries and territories setting a regulatory / guideline value 16 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO health-based value 1 Number of countries and territories setting the WHO health-based value 7 Number of countries and territories setting a regulatory / guideline value less than WHO health-based value 8 Maximum value set 2 mg/l Minimum value set 0.03 mg/l Median value 1.15 mg/l Of the 16 countries and territories specifying a value for 1,1,1-trichloroethane, seven specified the GV. Trichloroethene WHO Guideline value 0.02 mg/l (provisional P) Number of countries and territories setting a regulatory / guideline value 68 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 21 Number of countries and territories setting the WHO Guideline 7 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 40 Maximum value set 0.07 mg/l Minimum value set 0.001 mg/l Median value 0.01 mg/l Almost two thirds of the 104 countries and territories surveyed specified a value for trichloroethene, with the majority (40/68) specifying values less than the provisional GV. Several countries and territories specified 0.01 mg/l jointly with tetrachloroethene. 60 2,4,6-Trichlorophenol WHO Guideline value 0.2 mg/l (C)* Number of countries and territories setting a regulatory / guideline value 30 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 2 Number of countries and territories setting the WHO Guideline 18 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 10 Maximum value set 0.3 mg/l Minimum value set 0.002 mg/l Median value 0.2 mg/l *Concentrations at or below the health-based guideline value may affect the appearance, taste or odour of the water, leading to consumer complaints The majority of countries and territories (18/30) specifying a value for this parameter specified the GV. 2,4,5-T (2,4,5-Trichlorophenoxy acetic acid) WHO Guideline value 0.009 mg/l Number of countries and territories setting a regulatory / guideline value 24 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 5 Number of countries and territories setting the WHO Guideline 17 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 2 Maximum value set 0.1 mg/l Minimum value set 0.002 mg/l Median value 0.009 mg/l Twenty-four countries and territories specified a value for 2,4,5-Trichlorophenoxy acetic acid, and the majority of these parameter specified the GV. 61 Trifluralin WHO Guideline value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 19 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 3 Number of countries and territories setting the WHO Guideline 16 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.09 mg/l Minimum value set 0.02 mg/l Median value 0.02 mg/l Of the 19 countries and territories that specified a value for trifluralin the majority specified the GV. Trihalomethanes (Total) WHO Guideline value (the sum of the ratios of the concentrations for Bromodichloromethane, Bromoform, Chloroform and Dibromochloromethane to their guideline values) ≤1 Number of countries and territories setting a regulatory / guideline value 66 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 0 Number of countries and territories setting a regulatory / guideline value at the WHO Guideline 9 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 57 Maximum value set 1 Minimum value set 0.001 Median value 0.1 The GDWQ set out a fractionation approach for total trihalomethanes (THMs), in which the sum of the ratios of concentrations for bromodichloromethane, bromoform, chloroform and dibromochloromethane to their Gvs should not exceed 1. Information on these individual compounds is presented earlier in the section on organic parameters. The majority of the 66 countries and territories specifying a value for total THMs set a value below the GV, and only 10 specified a value for total THMs and a value for each of its constituent parameters. 62 Toluene WHO Guideline value 0.7 mg/l (C)* Number of countries and territories setting a regulatory / guideline value 34 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 4 Number of countries and territories setting the WHO Guideline 22 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 8 Maximum value set 1 mg/l Minimum value set 0.024 mg/l Median value 0.7 mg/l *Concentrations at or below the health-based guideline value may affect the appearance, taste or odour of the water, leading to consumer complaints Thirty-four countries and territories specified a value for toluene, with the majority specifying the GV. Vinyl Chloride WHO Guideline value 0.0003 mg/l Number of countries and territories setting a regulatory / guideline value 61 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 50 Number of countries and territories setting the WHO Guideline 11 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 0 Maximum value set 0.02 mg/l Minimum value set 0.0003 mg/l Median value 0.0005 mg/l The majority of countries and territories specifying a value for vinyl chloride set 0.0005 mg/l, greater than the GV of 0.0003 mg/L. 63 Xylenes WHO Guideline value 0.5 mg/l (C)* Number of countries and territories setting a regulatory / guideline value 31 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline 6 Number of countries and territories setting the WHO Guideline 20 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline 5 Maximum value set 10 mg/l Minimum value set 0.05 mg/l Median value 0.5 mg/l *Concentrations at or below the health-based guideline value may affect the appearance, taste or odour of the water, leading to consumer complaints Thirty-one countries and territories specified a value for xylenes, and almost two thirds of these set the GV. 64 Parameters relating to acceptability, taste and odour and appearance The GDWQ identify 26 chemically derived parameters and four biologically derived parameters relating to acceptability, taste, odour and appearance. The importance of these parameters is that if the water is unacceptable to consumers, it may lead to rejection of the water, and use of other aesthetically more acceptable but potentially less-safe waters. Generally the concentrations that cause rejection are significantly lower than those of concern for health. As such, with the exception of manganese, which is widely found in drinking-water sources, it may not be appropriate to directly regulate or monitor such parameters, as they may be addressed through a general requirement in the national standard or regulation that water be acceptable to the majority of consumers. For these parameters, the GDWQ may include a HBV, or a GV(C) in order to assist in determining a response when problems are encountered (and to provide reassurance with regard to possible health risks). Some parameters have recommended values, mainly based on consumer acceptance. All the countries and territories in the survey specified values for some of the chemical and physical parameters. Three countries and territories included general statements that potable water should be free of algae. Most of the values that were set were guidance or indicator levels rather than mandatory standards. The acceptability parameters most often specified were pH (hydrogen ion) (specified by 103 countries and territories), chloride (100), iron (99), aluminium and sulfate (97). The least specified parameters were petroleum oils (3), and dissolved oxygen (4). In addition, 79 countries and territories had descriptive requirements for the taste parameter, and 78 for the odour parameter, such as: “acceptable to most consumers”, “not offensive”, “not objectionable”, “acceptable to consumers and no abnormal change”. Eighteen countries and territories had numerical values for the odour parameter and eleven for the taste parameter. The details for copper, chlorine, 1,2- and 1,4-dichlorobenzene, ethylbenzene, manganese, styrene, toluene, 2,4,6-trichlorophenol and xylenes appear already in the sections on inorganic or organic parameters as appropriate. 65 Aluminium WHO Guidance A GV has not been established for aluminium although the GDWQ note that average residuals should not exceed levels needed to optimize coagulation in drinking-water plants that use aluminium-based coagulants (0.1-0.2 mg/l). It also notes that a health- based value of 0.9 mg/l could be derived, but this exceeds practicable levels based on coagulation in treatment plants. Number of countries and territories setting a regulatory / guideline value 97 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline recommendation of 0.2 mg/l 4 Number of countries and territories setting a regulatory / guideline value at the WHO Guideline recommendation of 0.2 mg/l 84 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline recommendation of 0.2 mg/l 10 Maximum value set 0.5 mg/l Minimum value set 0.03mg/l Median value 0.2 mg/l GDWQ also note that aluminium concentrations greater than 0.1-0.2 mg/l can lead to aesthetic issues All but fourteen of the 97 countries and territories specifying a value for aluminium set a value of 0.2 mg/l. Ammonium WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 81 (out of 104) Maximum value set 3 mg NH4/l Minimum value set 0.05 mg NH4/l Median value 0.2 mg NH4/l The threshold odour concentration of ammonia at alkaline pH is approximately 1.5 mg/l, and a taste threshold of 35 mg/l has been proposed for the ammonium cation. Ammonia is not of direct relevance to health at these levels, and no health-based guideline value has been 66 proposed. Eighty-one countries and territories specified a value for ammonium, with 47 specifying 0.5 mg NH4/l; 20 specifying 1.5 mg NH4 /l, and the rest specifying values ≤ 1 mg NH4 /l. Calcium WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 31 (out of 104) Maximum value set 500 mg/l Minimum value set 30 mg/l Median value 150 mg/l The GDWQ advise a taste threshold for calcium ion of 150 – 300 mg/l, depending on the associated anion. Thirty-one countries and territories specified a value for this parameter, although it was not always clear if the value specified was quoted as calcium ion or as a calcium salt. Chloramines WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 6 (out of 104) Maximum value set 4 mg/l Minimum value set 0.15 mg/l Median value 3.5 mg/l A GV of 3 mg/L is set for monochloramine, and the information is presented in the inorganic parameters section. No HBV or GV is set for di- and trichloramines, as the available data is inadequate to derive a health-based GV. For dichloramine, the organoleptic effects between 0.1 and 0.5 mg/l were found to be “slight” and “acceptable”. Odour and taste thresholds of 0.15 and 0.13 mg/l were reported, respectively. An odour threshold of 0.02 mg/l has been reported for trichloramine, and it has been described as “geranium”. Six countries and territories set a value for chloramines, ranging from 0.15 to 4 mg/l. 67 Chloride WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 100 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline recommendation of 250 mg/l 15 Number of countries and territories setting a regulatory / guideline value at the WHO Guideline recommendation of 250 mg/l 77 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline recommendation of 250 mg/l 8 Maximum value set 1200 Minimum value set 20 Median value 250 Chloride is one of the most specified aesthetic parameters, with 100 countries and territories specifying a value. The GDWQ mention that concentrations in excess of 250 mg/l are increasingly likely to be detected by taste, and most countries and territories specified this value. Chlorobenzene WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 7 (out of 104) Maximum value set 0.3 mg/l Minimum value set 0.001 mg/l Median value 0.1 mg/l No GV has been set for chlorobenzene, however the GDWQ mention that odour thresholds of 0.002–0.01 and 0.0003–0.03 mg/l have been reported for 1,2- and 1,4-dichlorobenzene, respectively. Odour thresholds of 0.01, 0.005–0.03 and 0.05 mg/l have been reported for 1,2,3-, 1,2,4- and 1,3,5-trichlorobenzene, respectively. A taste and odour threshold concentration of 0.03 mg/l has been reported for 1,2,4-trichlorobenzene. Seven countries and territories specified a value for chlorobenzene, ranging from 0.001 to 0.3 mg/L. 68 Chlorophenols (other than 2,4,6-trichlorophenol) WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 9 (out of 104) Maximum value set 0.3 mg/l Minimum value set 0.0001 mg/l Median value 0.003 mg/l Chlorophenols generally have very low taste and odour thresholds. The taste thresholds in water for 2-chlorophenol, and 2,4-dichlorophenol are 0.0001,and 0.0003 mg/l, respectively. Odour thresholds are 0.01 and 0.04 mg/l, respectively. Nine countries and territories specified a value for this parameter, ranging from 0.0001 to 0.3 mg/L. Colour WHO Guideline value (true colour units) None set Number of countries and territories setting a regulatory / guideline value 80 with numerical values (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO Guideline recommendation of 15 TCU mg/l 20 Number of countries and territories setting a regulatory / guideline value at the WHO Guideline recommendation of 15 TCU mg/l 44 Number of countries and territories setting a regulatory / guideline value less than WHO Guideline recommendation of 15 TCU 16 Maximum value set 50 TCU Minimum value set 0.5 TCU Median value 15 TCU The GDWQ suggest 15 TCU as the level for consumer acceptance. The majority (44/80) of countries and territories setting a value for the colour parameter set 15 TCU. Twenty-two countries and territories had only an advisory statement of “acceptable to consumers and no change”, and one country specified “colourless”. 69 Dissolved oxygen WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 4 (out of 104) Maximum value set 8 mg/l Minimum value set 4 mg/l Median value 6 mg/l Dissolved oxygen is one of the least specified parameters, with only four countries and territories specifying values ranging from 4 to 8 mg/L. Hardness WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 57 (out of 104) Maximum value set 1000 mg CaCO3/l Minimum value set 100 mg CaCO3/l Median value 500 mg CaCO3/l It was assumed that all quoted figures referred to mg CaCO3/l although this was not always clear, especially when no method was specified. Fifty-seven countries and territories set a value for this parameter, and several others also had target or desirable levels below their maximum value. Hydrogen sulphide WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 27 (out of 104), with numerical values Maximum value set 0.1 mg/l Minimum value set 0 mg/l Median value 0.05 mg/l All 27 countries and territories set values within the taste threshold of 0.05 – 0.1 mg/l quoted in the GDWQ. 70 Iron WHO Guideline value None set* Number of countries and territories setting a regulatory / guideline value 99 (out of 104) Maximum value set 2 mg/l Minimum value set 0.2 mg/l Median value 0.3 mg/l *However, the GDWQ indicates a precautionary level of 2 mg/l, which does not present a hazard to health Almost all countries and territories set a value for this parameter. Fifteen countries and territories set a value above the GDWQ aesthetic limit of 0.3 mg/l at which staining of laundry and fixtures may occur. Thirty-five countries and territories specified the lowest value of 0.2 mg/L. Magnesium WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 34 (out of 104) Maximum value set 1,000 mg/l Minimum value set 10 mg/l Median value 100 mg/l The GDWQ advise that the taste threshold for magnesium is probably less than the 150 – 300 mg/l range for calcium. Thirty-four countries and territories specified a value for this parameter, although it was not always clear whether the value specified was quoted as magnesium ion or as a magnesium salt. 71 Monochlorobenzene WHO Guideline value None specified WHO Health-based value 0.3 mg/l Number of countries and territories setting a regulatory / guideline value 14 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO health-based value 0 Number of countries and territories setting the WHO health-based value 4 Number of countries and territories setting a regulatory / guideline value less than WHO health-based value 10 Maximum value set 0.3 mg/l Minimum value set 0.003 mg/l Median value 0.1 mg/l Taste and odour thresholds of 0.01–0.02 mg/l and odour thresholds ranging from 0.04 to 0.12 mg/l have been reported for monochlorobenzene. Of the 14 countries and territories setting a value for this parameter, the majority specified a value below the HBV. Odour WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 19, with numerical values (out of 104) Maximum value set 6 DN Minimum value set 2 DN Median value 3 DN All countries and territories specifying a numerical value set dilution number (DN) as 3, except for two countries that specified 2 and 6. Seventy-eight countries and territories had an advisory statement such as “acceptable to consumers and no abnormal change”, “non-objectionable” or “not detectable”. 72 Petroleum Oils WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 3 (out of 104) Maximum value set 0.3 mg/l Minimum value set 0.1 mg/l Median value 0.2 mg/l Petroleum oils can give rise to the presence of a number of low molecular weight hydrocarbons that have low odour thresholds in drinking-water. Benzene, toluene, ethylbenzene and xylenes (BTEX) are considered in the organic parameters section. Only three countries and territories set values for this parameter. pH Maximum WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 103 (out of 104) Maximum value set pH 9.7 Minimum value set pH 8 Median value pH 8.5 The GDWQ do not establish a GV for pH, as it usually has no direct impact on consumers at levels found in drinking-water. It is however an important operational parameter, and the GDWQ indicate an optimum pH range of 6.5-8.5. Only one country out of the 104 included in the survey did not specify a value for this parameter. Forty-eight countries and territories specified a value above the GDWQ suggested pH 8.5, but many included the note that chlorine disinfectant is only effective below pH 8. The highest value of pH 9.7 was set by one country, and was described as an operational limit. pH Minimum WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 102 (out of 104) Maximum value set pH 7 Minimum value set pH 5 Median value pH 6.5 73 Only two countries did not specify a value for this parameter. Eight countries and territories specified a value below the optimum range discussed in the GDWQ of pH 6.5. Sodium WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 81 (out of 104) Maximum value set 400 mg/l Minimum value set 100 mg/l Median value 200 mg/l The GDWQ notes that at room temperature, the average taste threshold for sodium is 200 mg/l. Seventy-one of the 81 countries and territories set this value, and only seven set a higher value. Sulfate WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 97 (out of 104) Maximum value set 800 mg/l Minimum value set 50 mg/l Median value 250 mg/l The GDWQ suggest taste impairment is minimal below 250 mg/l but can be up to 1,000 mg/l for calcium sulfate. Ninety-seven countries and territories set a value for this parameter, and the majority (66) specified 250 mg/l. Synthetic Detergents (Anionic) (Surfactants) WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 33 (out of 104) Maximum value set 2 mg/l Minimum value set 0.01 mg/l Median value 0.5 mg/l The GDWQ advise that the concentration of detergents in drinking-water should not be allowed to reach levels giving rise to either foaming or taste problem. Thirty-three countries and territories specified a value for this parameter, of these, 14 set 0.5 mg/l. 74 Taste WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 12 (out of 104), with numerical values Maximum value set 6 DN Minimum value set 2DN Median value 3 DN Twelve countries and territories specified numerical values for taste, and nine of these specified 3 DN. Seventy-nine countries and territories had an advisory statement such as “acceptable to consumers and no abnormal change”, “non-objectionable” or “inoffensive”. Temperature WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 18 (out of 104) Maximum value set 35oC Minimum value set 15oC Median value 25oC None of the values for temperature were mandatory, being guiding levels or operational goals. None of the countries and territories’ documents indicated what would happen if temperatures rose above the suggested value. In addition to those with numerical values, seven countries and territories had descriptive levels such as: 2.5 oC above normal; “not objectionable”; “air temperature plus 3 oC”; “acceptable”; and “ambient”. Total dissolved solids WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 66 (out of 104) Maximum value set 2500 mg/l Minimum value set 200 mg/l Median value 1000 mg/l Sixty-six countries and territories set a value for this parameter. There was a wide range of values; from 200 mg/l to 2,500 mg/l. Thirty-six countries and territories specified 1000 mg/l, eleven specified 500 mg/l. 75 Trichlorobenzenes (total) WHO Guideline value None specified WHO Health-based value 0.02 mg/l Number of countries and territories setting a regulatory / guideline value 11 (out of 104) Number of countries and territories setting a regulatory / guideline value greater than WHO health-based value 3 Number of countries and territories setting the WHO health-based value 8 Number of countries and territories setting a regulatory / guideline value less than WHO health-based value 0 Maximum value set 0.03 mg/l Minimum value set 0.02 mg/l Median value 0.02 mg/l Eleven countries and territories specified a value for trichlorobenzenes, and of these, eight set the HBV of 0.02 mg/l. Odour thresholds of 0.01, 0.005–0.03 and 0.05 mg/l have been reported for 1,2,3-, 1,2,4- and 1,3,5-trichlorobenzene, respectively. A taste and odour threshold concentration of 0.03 mg/l has been reported for 1,2,4-trichlorobenzene. Turbidity WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 85 (out of 104), with numerical values Maximum value set 25 NTU Minimum value set 0.3 NTU Median value 5 NTU The GDWQ notes that turbidity should ideally be <1 NTU for water to be disinfected and that large well-run municipal supplies should be able to achieve turbidity levels of < 0.5 NTU at all times, with an average of </= 0.2 NTU. It also notes that turbidity levels of 4 NTU and above is visible to the naked eye. Sixteen countries and territories specified a value of 1 NTU or less. Many values were accompanied by comments, including one country that specified 20 NTU but stated that the monthly average of results must not exceed 2 NTU; and another that quoted 5 as an aesthetic limit but 1 NTU as an operational limit. Fifteen countries and territories had descriptive statements only such as “acceptable to consumers and no abnormal change”. 76 Zinc WHO Guideline value None set Number of countries and territories setting a regulatory / guideline value 74 (out of 104) Maximum value set 15 mg/l Minimum value set 1 mg/l Median value 5 mg/l The GDWQ note that zinc concentrations at around 4 mg/l may affect the taste of water. Thirty-five out of 72 countries and territories reporting a value for this parameter specified 3 mg/l or less. 77 Radiological parameters The GDWQ suggest screening levels for gross alpha and gross beta activity, as the process of identifying individual radionuclides is too cost-intensive for routine monitoring given their generally low concentration. If the screening levels for gross alpha and gross beta activity suggested by WHO are not being exceeded, the individual dose criterion (i.e. total dose) of 0.1 milliSieverts per year (mSv/year) will usually not be exceeded either. The idea of screening levels is that radioactivity should be assessed against these during routine monitoring. If the screening levels are being exceeded after having taken further samples to validate the findings, the contribution of K-40 (beta) should be subtracted from the gross beta activity following a separate determination of total potassium. If the screening values are still being exceeded, an analytical strategy for individual radionuclides should be determined. In general, countries and territories that specified values for radiological parameters did not deviate significantly from the GDWQ. Forty-eight countries and territories specified screening values for gross alpha and gross beta activity, two in terms of a ratio or annual dose. Some expressed their values in terms of Picocurie per litre (pCi/l); these have been converted to their equivalents as Becquerel per litre (Bq/l) for this report. Thirty five countries and territories specified a value for total dose in terms of mSv/yr. Only three of these also specified values for gross alpha and beta activity. The GDWQ list guidance levels for 191 radionuclides. However, most countries and territories specified values for only a few of these, including: radon (seven); radium-226 (seven); strontium-90 (five). Where countries and territories specified values for gross alpha and beta activity and total dose, most included advice on the steps that should be taken if any of these values were exceeded. 78 Total Dose / Individual Dose Criteria WHO/IDC guidance 0.1 mSv/year* Number of countries and territories setting a regulatory / guideline value 36 (out of 104) Number of countries and territories setting a regulatory / guidance level greater than WHO/IDC guidance 2 Number of countries and territories setting the WHO IDC guidance 34 Number of countries and territories setting a regulatory / guidance level less than WHO/IDC guidance 0 Maximum value set 1 mSv/year Minimum value set 0.1 mSv/year Median value 0.1 mSv/year *This value is translated into operational targets to be measured by water suppliers and regulators as the screening values (gross alpha and gross beta, which are listed in the tables below) and guidance levels (which are listed in Table 9.2 of Chapter 9 of the GDWQ). The GDWQ notes that the IDC represents a very low level of health risk and also refers to the International Radiation Basic Safety Standards (BSS), (IAEA, 2014) reference level. The BSS, which is co-sponsored by eight international organizations including WHO, has established a reference level for the radiation dose due to the consumption of drinking-water of 1 mSv/year. It is generally advisable for countries to establish a national standard between 0.1 and 1 mSv/year, where 0.1 mSv/year is achievable for most countries. Almost all countries have established their IDC as 0.1 mSv/year, and the EC Council Directive 2013/51/EURATOM also adopted a total indicative dose of 0.1 mSv/year. Only two countries out of the 36 that specified a value for this parameter set a value above 0.1 mSv/year. Gross alpha activity WHO Screening level 0.5 Bq/l Number of countries and territories setting a regulatory / guidance level 48 (out of 104) Number of countries and territories setting a regulatory / guidance level greater than WHO Screening level 3 Number of countries and territories setting the WHO Screening level 12 Number of countries and territories setting a regulatory / guidance level less than WHO Screening level 33 Maximum value set 0.56 Bq/l Minimum value set 0.01 Bq/l Median value 0.1 Bq/l Twelve countries and territories specified the WHO screening level (or its equivalent when their values are converted from pCI/l). 79 Gross beta activity WHO Screening level 1 Bq/l Number of countries and territories setting a regulatory / guidance level 48 (out of 104) Number of countries and territories setting a regulatory / guidance level greater than WHO Screening level 5 Number of countries and territories setting the WHO Screening level 37 Number of countries and territories setting a regulatory / guidance level less than WHO Screening level 6 Maximum value set 2.0Bq/l Minimum value set 0.1 Bq/l Median value 1 Bq/l Thirty-seven countries and territories specified the WHO screening level (or its equivalent when their values are converted from pCI/l). Five countries specified values above the WHO screening level, and six specified values less than the WHO screening level. 80 Microbiological parameters The GDWQ identify 43 microbial parameters, which include bacterial, viral, protozoan, and helminth pathogens, as well as toxic cyanobacteria. The verification of microbial water safety is normally based on testing of indicator organisms, and the GDWQ include a GV for Escherichia coli (E. coli) or thermotolerant coliforms). Countries and territories in the survey designated numerical standards for 24 microbiological parameters. However, nine of these parameters were designated by only one country and a further nine by less than ten countries and territories. Values for E. coli (or faecal coliforms or thermotolerant coliforms) were specified by 102 countries and territories, then total coliforms (97 countries and territories), enterococci (faecal streptococci) (46 countries and territories), sulphite-reducing Clostridia (Clostridium perfringens) (44 countries and territories), total heterotrophic bacteria at 22°C(19 countries and territories) and total heterotrophic bacteria at 37°C (13 countries and territories). The other parameters were: Enteric viruses and Pseudomonas aeruginosa (eight countries and territories); Cryptosporidium and Giardia (five countries and territories); Salmonella, somatic coliphages and Staphlococcus aureus (four countries and territories); pathogenic protozoa and Shigella (three countries and territories); and amoeba, Vibrio cholera, free living organisms, helminths, Legionella, nematodes, parasites and plankton (one country). The normal value for microbiological parameters, other than heterotrophic bacteria, was zero or absent per volume (usually 100 ml for bacterial parameters and 10 litres for protozoa) although many countries and territories’ values accepted that coliform bacteria would be detected in samples on occasions. In addition to setting values for some microbiological parameters, many countries and territories’ documentation included a statement the same as or similar to that in the European Drinking-water Directive that drinking-water “shall be free from any micro-organisms and parasites which, in numbers or concentrations, constitute a potential danger to human health”. 81 Clostridium perfringens (Sulphite-reducing anaerobes) WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 44 (out of 104) Maximum value set 0 per 100 ml Minimum value set 0 per 100 ml Median value 0 per 100 ml The GDWQ state that Clostridium perfringens has only limited value as a possible indicator of enteric viruses and protozoan (oo)cysts but may be useful as an indicator of the effectiveness of filtration processes. All countries and territories specifying a value for this parameter specified zero per 100 ml (or in some cases 20 ml or 50 ml) for this parameter. Coliform bacteria (Total) WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 98 (out of 104) Maximum value set 150 per 100 ml Minimum value set 0 per 100 ml Median value 0 per 100 ml The GDWQ highlight that total coliform bacteria include organisms that can survive and grow in water so they are not useful as an indicator of faecal pathogens. It recommends that total coliforms should be absent immediately after treatment and presence of these organisms indicates inadequate treatment. Few countries and territories appeared to recognize this in their setting values. While six countries and territories did not specify a value for total coliforms, the others generally specified a value of zero for this parameter. Some specified <1.1 per 100 ml for analysis by most probable number technique. Where the value specified was greater than zero (e.g. 10 per 100 ml; 6 per 100 ml; or 3 per 100 ml), in most cases this was qualified by not detecting coliform bacteria in two consecutive samples or 95% of annual samples or both. One country specified 10 per 100ml as an operational value; another specified 100 coliform bacteria per 100 ml in a maximum of 1% of samples;10 per 100 ml in a maximum of 4% of samples; and “not detected” in a minimum of 95% of samples. One country designated the highest value as a maximum allowable range of 50 – 150 per 100 ml, but a recommended maximum limit of 10 per 100 ml. 82 Enterococci (Faecal streptococci) WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 47 (out of 104) Maximum value set 0 per 100 ml Minimum value set 0 per 100 ml Median value 0 per 100 ml The GDWQ advise that intestinal enterococci can be used as an indicator of faecal pollution and may survive longer in water than E coli. All countries and territories specifying a value for this parameter specified zero per 100 ml, and one specified that the value should be zero per 100 ml in 95% of samples (where more than 20 are taken annually) and not be present in consecutive samples. Escherichia coli (Faecal coliforms, Thermotolerant coliforms) WHO Guideline value Must not be detectable in any 100ml sample Number of countries and territories setting a regulatory / guideline value 103 (out of 104) Maximum value set 1 per 100 ml Minimum value set 0 Median value 0 For the purposes of this survey, faecal coliforms and thermotolerant coliforms have not been counted separately where they have been specified by countries and territories in addition to E coli because the value has always been zero per 100 ml. The GDWQ advise that the presence of E coli (or thermotolerant coliforms) provides evidence of recent faecal contamination. All countries and territories specified a value of zero per 100 ml except one country which specified 1 per 100 ml in a maximum of 1% of samples. One country did not specify a value for this parameter, just specifying zero per 100 ml for coliforms. 83 Total heterotrophic bacteria 22oC WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 19 (out of 104) Maximum value set 10,000 cfu per ml Minimum value set 5 cfu per ml Median value 100 cfu per ml The GDWQ advise that the test for this parameter has little value as an indicator of pathogen presence but can be useful in operational monitoring as a treatment and disinfectant indicator and for assessing the cleanliness of distribution systems. The objective is to keep numbers as low as possible. The EU countries specified “no abnormal change” for this parameter. Total heterotrophic bacteria 37oC WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 14 (out of 104) Maximum value set 500 cfu per ml Minimum value set 0 cfu per ml Median value 100 cfu per ml The GDWQ advise that the test for this parameter has little value as an indicator of pathogen presence but can be useful in operational monitoring as a treatment and disinfectant indicator and for assessing the cleanliness of distribution systems. The objective is to keep numbers as low as possible. 84 Additional parameters In the documentation used for this survey countries and territories specified 865 numerical values for 287 inorganic, organic, aesthetic and physical parameters that do not have a WHO GV, HBV or aesthetic limit. The additional parameters with numerical standard values most often specified, and reported in this section are: Conductivity (51 countries and territories); total polynuclear aromatic hydrocarbons (PAH) (44); oxidizability (permanganate value) (43); phenols (35); formaldehyde (19); silver (24); potassium (12); and propanil (11). Conductivity WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 51 (out of 104) Maximum value set 2700 S/cm Minimum value set 170 S/cm Median value 2500 S/cm Almost half (51/104) of the countries and territories included in the survey specified a value for conductivity. A wide range of values were specified, from 170 to 2,700 S/cm. Twenty-eight countries and territories specified 2500 S/cm. Formaldehyde WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 19 (out of 104) Maximum value set 1 mg/l Minimum value set 0.02 mg/l Median value 0.9 mg/l The GDWQ advise that this parameter occurs in drinking-water at concentrations well below those of health concern and specifies a tolerable concentration of 2.6 mg/l for ingested formaldehyde. Nineteen countries and territories specified a value for formaldehyde, and of these, eleven set 0.9 mg/l. 85 Oxidizability (permanganate value) WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 43 (out of 104) Maximum value set 20 mg/l Minimum value set 3 mg/l Median value 5 mg/l Forty-three countries and territories specified a value for this parameter, with the majority (37/43) setting mg/l. Total Polynuclear Aromatic Hydrocarbons (PAH) WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 44 (out of 104) Maximum value set 0.01 mg/l Minimum value set 0.0001 mg/l Median value 0.0001 mg/l The GDWQ do not advise a health-based guideline value for total PAH. Benzo(a)pyrene has a health-based value of 0.0007 mg/l (see organic parameters). For fluoranthene it advises that it occurs in drinking-water at concentrations well below those of health concern but a health- based value of 0.004 can be calculated on available data. Forty-four countries and territories specified a value for total PAHs, of these, 33set 0.0001 mg/l. Phenols WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 35 (out of 104) Maximum value set 0.3 mg/l Minimum value set 0.0003 mg/l Median value 0.002 mg/l The GDWQ do not advise a health-based guideline value for total phenols. 2,4,6- Trichlorophenol has a provisional GV (C) of 0.2 mg/l (see organic parameters), and summary information on chlorophenols other than 2,4,6-trichlorophenol is presented in the sections on acceptability parameters. Thirty-five countries and territories specified a value for phenols. Almost half (15/35) set 0.002 mg/l. 86 Potassium WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 12 (out of 104) Maximum value set 50 mg/l Minimum value set 1.5 mg/l Median value 10 mg/l The GDWQ advise that currently, there is no evidence that potassium levels in municipally treated drinking-water, even water treated with potassium permanganate, are likely to pose any risk for the health of consumers. It is not considered necessary to establish a health-based guideline value for potassium in drinking-water. Twelve countries and territories specified a value for potassium. Propanil WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 11 (out of 104) Maximum value set 0.7 mg/l Minimum value set 0.02 mg/l Median value 0.02 mg/l The GDWQ advise that although a health-based value for propanil can be derived, this has not been done, because propanil is readily transformed into metabolites that are more toxic. Two of these metabolites, 3,4-dichloroaniline and 3,3′ ,4,4′ -tetrachloroazobenzene, are more toxic and more persistent than the parent compound. Therefore, a guideline value for propanil is considered inappropriate and there are inadequate data on the metabolites to allow the derivation of guideline values for them. All of the eleven countries and territories setting a value for propanil specified 0.02 mg/l except one, which specified 0.7 mg/l. No country or territory specified a value for metabolites of propanil. 87 Silver WHO Guideline value None specified Number of countries and territories setting a regulatory / guideline value 24 (out of 104) Maximum value set 0.1 mg/l Minimum value set 0.01 mg/l Median value 0.05 mg/l The GDWQ advise that the available data is inadequate to permit the derivation of a health- based guideline value; however, a concentration of 0.1mg/l could be tolerated without risk to health. Twenty-four countries and territories specified a value for silver, and none set a value above 0.1 mg/l. 88 Conclusion The GDWQ emphasize the importance of setting risk-based standards and adopting the specifications in the guidelines to local resources and needs. The GDWQ do not only provide guidance on standard-setting, but also on a holistic water safety framework that includes the establishment of national standards, as well as preventive risk management approaches (e.g. Water Safety Plans), and independent surveillance. For the purpose of this report, only the standards that countries and territories are specifying for different water quality parameters were reviewed. In that context, it was found that the GDWQ play an overall significant role in countries and territories’ setting of values that define drinking-water quality. More than half of the countries and territories in the survey reference the GDWQ directly (e.g. Iceland) or indirectly (e.g. Norway) by referencing other countries and territories which referenced the GDWQ. This figure is actually likely to be higher as the full value standard was not always available. Another limitation of this report is that direct comparison between countries and territories is difficult because standards in different countries and territories can be mandatory, recommended and/or risk-based. Direct comparison is further difficult and should be approached with caution, as national standards should be developed considering the local context. It must also be kept in mind that countries and territories review their specification for drinking-water quality with a different rhythm than to when updates to the GDWQ are published. However, the values included in the GDWQ and their role in providing orientation to countries and territories is underlined by the number of countries and territories making reference to the GDWQ in their specifications, and in a great many cases specifying GVs. 89 References and source documentation Guidelines for Drinking-water Quality. Fourth Edition. 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Norma Chilena Oficial NCh409/1.Of2005 China GB 5749-2006 Standards for drinking-water quality Taiwan, China Drinking-water Quality Standards (Drinking-water Management Act) 2009 Colombia Normas oficiales para la calidad del agua Colombia 1994 91 Croatia O Zdravstvenoj Ispravnosti Vode Piće (Ministarstvo Zdravstvai Socijalne Skrbi (1593) (Regulations on drinking-water) 2008, Ministry of Social Welfare Costa Rica Reglamento para la Calidad del Agua Potable 2005 Cuba Agua Potable Requisitos Sanitarios NC 93-02:1997 Cyprus The Quality of Water Intended for Human Consumption (Monitoring and Control) Law of 2001 (N.87(I)/2001) and Regulations. 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Water Quality - Specification for Drinking-water. 4th edition. Ghana Standards Authority. Greece Áñ. Öýëëïõ 892 11 Éïõëßïõ 2001 Guatemala Norma Guatemalteca Obligatoria Agua Potable 2000 Honduras República de Honduras Ministerio de Salud - Norma Técnica para la calidad del Agua 1995 93 Hungary 201/2001. (X. 25.) Korm. Rendelet az ivóvíz minőségi követelményeiről és az ellenőrzés rendjéről Iceland Reglugerd um neysluvatn 2001 India Drinking-water Specification Second revision of IS:10500 2012 Indonesia Nomor 492/Menkes/Per/IV/2010 Iraq The Standardization's Specification No 417 2001 Ireland Environmental Protection Agency Drinking-water Regulations 2014 Israel Public Health Regulations (Sanitary Quality of Drinking-water) 1974 Consolidated Version 2000 Italy Decreto Legislativo 2 febbraio 2001, n. 31 "Attuazione della direttiva 98/83/CE relativa alla qualita' delle acque destinate al consumo umano" Japan Ministerial Ordinance Concerning Drinking-water Quality Standards - 2010 Jordan Jordan Institute for Standards and Metrology. Technical Regulations: Water – Drinking water; 2008. (286:2008-5th edition) Kenya Kenya Bureau of Standards. Specification fir Drinking-water KS 05-459: Part 1:1996 94 Lao People’s Democratic Republic Decree for drinking-water quality standard in Lao People’s Democratic Republic and standard for checking of water resource No 953/MOH. 2003 Latvia Ministru kabineta noteikumi Nr.235 Rīgā 2003.gada 29.aprīlī (prot. Nr.23 71.§) Dzeramā ūdens obligātās nekaitīguma un kvalitātes prasības, monitoringa un kontroles kārtība Lebanon Ministry of Environment Decree No 52/1 - Standards for the Minimization of Pollution of Air, Water and Soil 2006 Lithuania Dėl lietuvos higienos normos HN 24:2003 “Geriamojo vandens saugos ir kokebės reikalavimai” Luxembourg Règlement grand-ducal du 7 octobre 2002 relatif à la qualité des eaux destinées à la consommationhumaine Malaysia National Standard for Drinking-water Quality 2004 Malta LN23 / 2004 Kwalità ta 'ilma maħsub għal regolamenti konsum tal-bniedem 2004 (LN23/2004 Quality of water intended for human consumption regulations 2004) Mexico Modificacion a la Norma Oficial Mexicana NOM-127-SSA1-1994, Salud ambiental. Agua para uso y consumo humano. Límites permisibles de calidad y tratamientos a que debe someterse el agua para su potabilización. Morocco Norm Marocaine NM 03.7.001 Qualité des eaux d'alimentation humane 2006 Mozambique Regulamento sobre a Qualidade da Água para o Consumo Humano 2004 95 Nepal National Drinking-water Quality Standards 2005 Netherlands Wet van 18 juli 2009, houdende nieuwe bepalingen met betrekking tot de productie en distributie van drinkwater en de organisatie van de openbare drinkwatervoorziening (Drinkwaterwet) New Zealand Drinking-water Standards for New Zealand 2005 (Revised 2008) Nicaragua Norma Regional de Calidad del Agua Comite Coordinador Regional de Instituciones de Agua Potable y Saneamiento de Centroamerica, Panama y Republica Dominicana – Capre 1994 Nigeria Nigerian Standard for Drinking-water Quality NIS 554: 2007 Norway FOR 2001-12-04 No 1372: Forskrift om vannforsyning og drikkevann Oman Omani Standard No 8/2006 Unbottled Drinking-water Pakistan National Standards for Quality Drinking-water 2009 Panama Reglamento Técnico DGNT-COPANIT 23-395-99 Agua, Agua Potable Definiciones y Requistos Generales Paraguay Ley General del Marco Regulatorio y Tarifario del Servicio de Agua Potable y Alcantarillado Sanitario Ley No 1.614/2000 Peru Reglamento de la Calidad del Agua para Consumo Humano. DS No 031-2010-SA 96 Philippines Philippine National Standards for Drinking-water 2007 Poland Rozporządzenia Ministra Zdrowia z dnia 29 marca 2007r. W sprawie jakości wody przeznaczonej do spoŜycia przez ludzi (Dz. U. Nr 61, poz. 417) Portugal Ministério do Ambiente, do Ordenamento do Território e do Desenvolvimento Regional Decreto-Lei no 306/2007 de 27 de Agosto Romania Lege nr 458(r1) din 08/07/2002. Privind calitatea apei potabile The Russian Federation II.Предельно допустимые концентрации (ПДК) химических веществ в воде водныхобъектов хозяйственно-питьевого и культурно-бытового водопользования (Permissible concentration (MPC) of chemicals in the water for drinking, cultural and domestic use) Resolution of the Sanitary Inspector of the The Russian Federationn Federation (30.04.2003 Moscow № 78 Овведении в действие ГН 2.1.5.1315-03) Rwanda Potable Water - Specification. Rwanda Standard RS435:2009 Rev 1:2011 Samoa Samoa National Drinking-water Standards 2008 Sierra Leone Draft Guidelines for Drinking-water Policy (Water Supply and Sanitation for Sierra Leone, United Nations Economic Commission for Africa) 2007 Singapore Environmental Public Health (Quality of Piped Drinking-water) Regulations 2008 Slovakia 97 Zbierka zákonov č. 496/2010 ktorým sa mení a dopĺňa nariadenie vlády Slovenskej republiky č. 354/2006 Z. z., ktorým sa ustanovujú požiadavky na vodu určenú na ľudskú spotrebu a kontrolu kvality vody určenej na ľudskú spotrebu Slovenia Rules on water intended for human consumption. Based on the Act Regulating the Sanitary Suitability of Foodstuffs, Products and Materials Coming into Contact with Foodstuffs (Official Gazette of RS, no. 52/00 and 42/02), Spain Real Deccreto 140/2003, de 7 Febrero, por el que se establecen los criterios sanitarios de la calidad del agua de consume humano South Africa South African National Standard SANS241:2011 Drinking-water Republic of Korea Management of Drinking-water Act 2008 Sri Lanka Sri Lanka Standards for potable water - SLS 614, 198 Sudan Drinking-water Standard ICS 13.060.00 2002 Suriname Anteproyecto de Ley 2003 Sweden Livsmedelsverkets föreskrifter (SLVFS 2001:30) om dricksvatten Syrian Arab Republic Syrian Arab Republic - Drinking-water Quality Standards 1994 Switzerland Criterès d’appréciation pour l’eau de boisson: composition chimique; composition microbiologie. SCVA VD / Inspection des eaux. Juillet 2008 98 The United Republic of Tanzania TZS 789:2003 - Drinking (potable) water - Specification Thailand Notification of the Ministry of Industry, No. 322, B.E. 2521 (1978), issued under the Industrial Products Standards Act B.E. 2511 (1968) Tunisia Project of Tunisian Standard PTS 14.09 (1993) Turkey İnsani Tüketim Amaçli Sular Hakkinda Yönetmelik (Regulations on water for human consumption) 2005 Uganda Uganda Standard US 201:2008 Drinking (potable) water - Specification Ukraine Гигиенические требования к воде питьевой, предназначенной для потребления человеком (ГCанПиН 2.2.4-171-10) (Hygienic requirements for drinking-water intended for human consumption) (GCanPiN 2.2.4-171-10): 2008 United Arab Emirates The Water Quality Regulations (Fourth Edition) 2014. The Regulation and Supervision Bureau for the water, wastewater and electricity sector in the Emirate of Abu Dhabi. United Kingdom The Water Supply (Water Quality) Regulations 2000 (England and Wales) (Similar Regulations apply in Scotland and Northern Ireland) Uruguay Agua potable - Requisitos, Instituto Uruguayo de Normas Técnicas 833:2008 USA National Primary Drinking-water Regulations 2009 Venezuela Normas Sanitaias de Calidad del Agua potable 1998 99 Viet Nam Nườc cấp sinh hoạt - yêu cấu chất lượng TCVN 5502 : 2003 (Domestic supply water - Quality requirements) West Bank and Gaza Strip Palestine Standard 41 1997 Zambia ZS 190:2010, ICS 13.060.20 (Drinking-water Quality - Specification), Zambian Bureau of Standards 100 For more information, contact: Water, Sanitation, Hygiene and Health World Health Organization 20, Avenue Appia 1211 Geneva 27 Switzerland E-mail: gdwq@who.int http://www.who.int/water_sanitation_health/water-quality/en/