This fourth edition incorporating the first addendum, of the World Health Organization's Guidelines for Drinking-water Quality builds on over 50 years of guidance by WHO on drinking-water quality, which has formed an authoritative basis for the setting of national regulations and standards for water safety in support of public health.

It is the product of significant revisions to clarify and elaborate on ways of implementing its recommendations of contextual hazard identification and risk management, through the establishment of health-based targets, catchment-to-consumer water safety plans and independent surveillance. It reflects the renewed focus on primary prevention.

Significant additional guidance on good practice is presented, incorporating changes introduced by the first and second addenda to the third edition. Emerging water management issues are comprehensively addressed for a range of circumstances, from household water treatment and safe storage and the bulk supply of water over long distances to the potential implications of climate change.

Additional risk assessments are presented for a number of new chemical and microbial hazards and applied to a suite of pesticides used for public health purposes. Existing reviews on chemicals and waterborne pathogens have been revised to account for new scientific information. The chapter on radiological aspects of drinking-water quality has been comprehensively updated.

Even more than the previous edition, this new edition incorporating the first addendum, emphasizes achievable practices and the formulation of sound regulations, applicable to low-income, middle-income and industrialized countries alike, that aim to prevent a potential health crisis caused by the consumption of unsafe drinking-water, against the backdrop of rapid urbanization, water scarcity and climate change.

Contents

• Preface
• ACKNOWLEDGEMENTS
• Abbreviations used in text
• 1. Introduction
  • 1.1. General considerations and principles
  • 1.2. Roles and responsibilities in drinking-water safety management
  • 1.3. Supporting resources to the Guidelines
• 2. A conceptual framework for implementing the Guidelines
  • 2.1. Health-based targets
  • 2.2. Water safety plans
  • 2.3. Surveillance
  • 2.4. Verification of drinking-water quality
  • 2.5. Identifying priority concerns
  • 2.6. Developing drinking-water quality standards
  • 2.7. Drinking-water regulations and supporting policies and programmes
• 3. Health-based targets
  • 3.1. Setting health-based targets
  • 3.2. Disability-adjusted life years, tolerable disease burden and reference level of risk
  • 3.3. Types of health-based targets
• 4. Water safety plans
  • 4.1. System assessment and design
  • 4.2. Operational monitoring and maintaining control
  • 4.3. Verification
  • 4.4. Management procedures for piped distribution systems
  • 4.5. Management of community and household water supplies
  • 4.6. Documentation and communication
  • 4.7. Planned review
• 5. Surveillance
  • 5.1. Types of approaches
  • 5.2. Adapting approaches to specific circumstances
  • 5.3. Adequacy of supply
  • 5.4. Planning and implementation
  • 5.5. Reporting and communicating
• 6. Application of the Guidelines in specific circumstances
  • 6.1. Climate change, water scarcity and heavy rainfall
  • 6.2. Rainwater harvesting
  • 6.3. Vended water
  • 6.4. Bulk water supply
  • 6.5. Desalination systems
  • 6.6. Dual piped water supply systems
  • 6.7. Emergencies and disasters
  • 6.8. Temporary water supplies
  • 6.9. Buildings
  • 6.10. Health-care facilities
  • 6.11. Safe drinking-water for travellers
  • 6.12. Aircraft and airports
  • 6.13. Ships
  • 6.14. Packaged drinking-water
  • 6.15. Food production and processing
• 7. Microbial aspects
  • 7.1. Microbial hazards associated with drinking-water
  • 7.2. Health-based target setting
  • 7.3. Occurrence and treatment of pathogens
  • 7.4. Microbial monitoring
  • 7.5. Methods of detection of faecal indicator organisms
  • 7.6. Identifying local actions in response to microbial water quality problems and emergencies
• 8. Chemical aspects
  • 8.1. Chemical hazards in drinking-water
  • 8.2. Derivation of chemical guideline values and health-based values
  • 8.3. Analytical achievability
  • 8.4. Treatment
  • 8.5. Guideline values for individual chemicals, by source category
  • 8.6. Pesticides used in water for public health purposes
  • 8.7. Identifying local actions in response to chemical water quality problems and emergencies
• 9. Radiological aspects
  • 9.1. Sources and health effects of radiation exposure
  • 9.2. Rationale for screening levels and guidance levels
  • 9.3. Monitoring and assessment for dissolved radionuclides
  • 9.4. Guidance levels for radionuclides commonly found in drinking-water
  • 9.5. Analytical methods
  • 9.6. Remedial measures
  • 9.7. Radon
  • 9.8. Risk communication
• 10. Acceptability aspects: Taste, odour and appearance
  • 10.1. Biologically derived contaminants
  • 10.2. Chemically derived contaminants
  • 10.3. Treatment of taste, odour and appearance problems
  • 10.4. Temperature
• 11. Microbial fact sheets
  • 11.1. Bacterial pathogens
  • 11.2. Viral pathogens
  • 11.3. Protozoan pathogens
  • 11.4. Helminth pathogens
  • 11.5. Toxic cyanobacteria
  • 11.6. Indicator organisms
• 12. Chemical fact sheets
  • 12.1. Chemical contaminants in drinking-water
  • 12.2. Pesticides used for vector control in drinking-water sources and containers
• ANNEX 1. Supporting documentation to the Guidelines
• ANNEX 2. References cited
• ANNEX 3. Chemical summary tables
• ANNEX 4. Analytical methods and achievability
• ANNEX 5. Treatment methods and performance
• ANNEX 6. Supporting information on radionuclides
• ANNEX 7. Contributors to the development of the Guidelines for drinking-water quality: fourth edition incorporating the first addendum

Suggested citation:

Guidelines for drinking-water quality: fourth edition incorporating the first addendum. Geneva: World Health Organization; 2017. Licence: CC BY-NC-SA 3.0 IGO.

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