Chemical safety of drinking-water : assessing priorities for risk assessment

This book provides guidance on the chemical safety of drinking-water. Chemical contaminants of drinking-water are often considered a lower priority than microbial contaminants, because adverse health effects from chemical contaminants are generally associated with long-term exposures, whereas the effects from microbial contaminants are usually immediate. Nonetheless, chemicals in water supplies can cause very serious problems. The objective of this publication is to help users at national or local level to establish which chemicals in a particular setting should be given priority in developing strategies for risk management and monitoring of chemicals in drinking-water. The document will be useful to public health authorities, those responsible for setting standards and for surveillance of drinking-water quality, and to water supply agencies responsible for water quality management. In particular, this publication will be applicable in settings where information on actual drinking-water quality is limited, which is the case in many developing countries and in rural areas of some developed countries.--Publisher's description. Contents......Page 4 Foreword......Page 8 Acknowledgements......Page 10 Abbreviations and acronyms......Page 12 Part A – Assessing and managing priorities......Page 14 1. Introduction......Page 16 1|2. Objective......Page 18 1|4. Administrative and policy context......Page 19 1|5. How to use this publication......Page 21 1|6. References......Page 23 2. General principles and basis for prioritizing chemicals......Page 26 2|1. Principles for assigning priorities for risk management......Page 28 2|2. Setting priorities with limited information......Page 29 2|3. Factors affecting chemical concentrations along pathways......Page 30 2|4. Frequent priorities for risk management......Page 31 2|5. References......Page 32 3. Developing and implementing risk management strategies......Page 34 3|1. Identifying priority chemicals in a drinking-water supply......Page 36 3|3. Overview of management procedures......Page 37 3|4. References......Page 41 Part B – Identifying specific chemicals......Page 44 4. Naturally occurring chemicals......Page 46 4|1. General......Page 48 4|3. Data sources......Page 49 4|5. Guidance on identifying relevant chemicals......Page 50 4|6. References......Page 54 5. Chemicals from agricultural activities......Page 56 5|2. Data sources......Page 58 5|3. Use of human excrement, animal manure, inorganic fertilizer and biosolids......Page 59 5|4. Intensive animal practices......Page 61 5|5. Use of pesticides......Page 62 5|6. Irrigation and drainage......Page 63 5|7. References......Page 64 6. Chemicals from human settlements......Page 66 6|1. Introduction......Page 68 6|3. Sewage systems and on-site sanitation......Page 70 6|4. Waste disposal......Page 71 6|5. Urban runoff......Page 72 6|6. Fuel storage sites......Page 73 6|9. References......Page 74 7. Chemicals from industrial activities......Page 76 7|2. Data sources......Page 78 7|3. Extractive industries......Page 79 7|4. Manufacturing and processing industries......Page 82 7|5. Reference......Page 85 8. Chemicals from water treatment and distribution......Page 88 8|2. Chemicals used in treatment......Page 90 8|4. Distribution systems......Page 92 8|5. References......Page 93 Part C – Appendices......Page 97 Appendix 1. Potential sources and uses of chemicals considered in the WHO Guidelines for Drinking-water Quality......Page 98 Appendix 2. Chemicals potentially discharged through effluents from industrial sources......Page 122 Appendix 3. Association of pesticides with crops and crop types......Page 130 Appendix 4. Practical comments on selected parameters......Page 138 C......Page 154 I......Page 155 P......Page 156 Z......Page 157