Chlorination in various forms has been the predominant method of drinking water disinfection in the United States for more than 70 years. The seventh volume of the Drinking Water and Health series addresses current methods of drinking water disinfection and compares standard chlorination techniques with alternative methods. Currently used techniques are discussed in terms of their chemical activity, and their efficacy against waterborne pathogens, including bacteria, cysts, and viruses, is compared.

Charts, tables, graphs, and case studies are used to analyze the effectiveness of chlorination, chloramination, and ozonation as disinfectant processes and to compare these methods for their production of toxic by-products. Epidemiological case studies on the toxicological effects of chemical by-products in drinking water are also presented.

Contents

• List of Participants
• Preface
• 1. Executive Summary
• 2. Disinfection Methods and Efficacy
  • Current Practices
  • Chlorination
  • Alternative Methods
  • Waterborne Pathogens
  • References
• 3. Chemistry and Toxicity of Disinfection
  • Chlorination
  • Epidemiological Studies
  • Alternative Methods
  • Oxidation Processes
  • References
• 4. Chemistry and Toxicity of Selected Disinfectants and By-Products
  • Chlorine
  • Chlorine Dioxide
  • Chloramines
  • Chlorite
  • Chlorate
  • Trihalomethanes
  • Haloacids
  • Haloaldehydes
  • Haloketones
  • Haloacetonitriles
  • Chloropicrin
  • Chlorophenols
  • References
• 5. Conclusions and Recommendations
  • Disinfection Methods and Efficacy
  • Chemistry and Toxicity of Disinfection

NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.

This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine.

This project has been funded by the U.S. Environmental Protection Agency under Contract No. 68-01-3169 with the National Academy of Sciences. The contents of this document do not necessarily reflect the views and policies of the Environmental Protection Agency, and an official endorsement should not be inferred.

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The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy's purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Frank Press and Dr. Robert M. White are chairman and vice chairman, respectively, of the National Research Council.