Updating the hygienic standards of chemical substances regulated in water according to the general sanitary indicator of harmfulness, taking into account modern data on their hazard

Introduction.The approach to the development of differentiated hygienic standards for chemical substances for different types of water use, depending on the possible impact on human health or the conditions of water use of the population, and the algorithm for their establishment require testing and improvement due to a number of restrictions on the availability of the necessary data on the toxicological and hygienic characteristics of previously standardized substances.The purpose of the research was to update and adjust, using the proposed Algorithm of hygienic standards - the maximum permissible concentration (MPC) in drinking water, the limiting indicator of harmfulness, and, if necessary, the hazard class of chemicals regulated in the water of water bodies according to the general sanitary indicator of harmfulness, taking into account the hazard of affecting human health, as well as to improve this algorithm.Material and methods. The objects of the study were the hygienic standards of chemicals regulated in the water of water bodies according to the general sanitary indicator of harmfulness. Research methods included searching and sorting information from MedLine, PubMed, PubChem databases, the Hazardous Substances Data Bank (HSDB and CHEMINFO), the WATERTOX database (RAMS. STC: 02296014904), grouping of chemicals by chemical classes, specified characteristics, establishment of common and distinct signs of toxicity of substances, expert assessment.Results. From 204 substances regulated in the water of water bodies according to the general sanitary indicator of harmfulness, a group of substances (23 in total) was formed. For these chemicals, there are data on threshold concentrations for organoleptic, general sanitary and sanitary-toxicological indicators of harmfulness. The MPC in drinking water was updated, the limiting hazard index was adjusted from the general sanitary to the organoleptic without changing the hazard class for 9 substances, for the remaining 14 substances it was recommended to replace the general sanitary limiting hazard index with the sanitary-toxicological one, including for 6 substances, the hazard classes of which were changed from the 4th to the 3rd.Limitations. Lack of information about the previously experimentally established maximum non-effective dose or sufficient literature data on the toxicity of the substance that would make it possible to predict safe levels for human health.Conclusion. The selection and analysis of information made it possible for the first time to implement an approach to introduce differentiated hygienic standards for chemicals in water, depending on the type of water use. Updating the MPC of chemicals regulated in the water of water bodies according to the general sanitary indicator of harmfulness will eliminate unnecessary requirements for the purification of drinking water from chemicals to levels below the maximum ineffective ones that do not pose a threat to public health and sanitary conditions of water use.Compliance with ethical standards. The study does not require the submission of a conclusion from the biomedical ethics committee or other documents.Authors’ contribution: Tulskaya E.A., Belyaeva N.I., Khamidulina Kh.Kh., Tarasova E.V., Nazarenko A.K. – collection and processing of material; Sinitsyna O.O. – conception and design of the study, generalization of data, writing and text editing; Turbinskii V.V. – concept and design of the study, text editing. All authors – responsibility for the integrity of all parts of the article, approval of the final version of the article.Conflict of interest. The authors declare that there are no obvious and potential conflicts of interest in connection with the publication of this article.Funding. The study had no sponsorship.Received: March 05, 2025 / Revised: July 15, 2025 / Accepted: November 25, 2025 / Published: January 15, 2026