Public health risk from contamination of drinking water with carcinogenic chemicals in centralized water supply systems

The paper presents the results of assessing the carcinogenic risk to public health from consuming drinking water contaminated with priority chemicals at the level of their hygienic standards. A comparative analysis of SanPiN 1.2.3685-21 “Hygienic Standards and Requirements for Ensuring the Safety and (or) Harmlessness of Environmental Factors for Humans” and repealed SanPiN 2.1.4.1074-01 “Drinking Water and Water Supply to Populated Areas. Drinking Water. Hygienic Requirements for Water Quality of Centralized Drinking Water Supply Systems. Quality Control” valid since March 01, 2021, is carried out. Maximum allowable concentrations of carcinogenic chemical substances and values of slope factors and risk potential factors have been analyzed. A comparative analysis of SanPiN 1.2.3685-21 that is currently in force and the US EPA “2018 Edition of the Drinking Water Standards and Health Advisories Tables” has been conducted. The average daily intake doses of each studied substance in drinking water at the level of maximum permissible concentrations were determined. It has been found that, despite the tightening of standards for some substances, the content of many carcinogens in water at the maximum allowable concentrations or below can lead to high values of potential carcinogenic risk, and a list of activities is needed to complement the current standards regarding the quality of water.