On the issue of substantiating the maximum permissible concentration (MPC) of benzoic acid and its derivatives in water

Introduction. Testing of new methodological approaches to the system of hygienic regulation of chemicals in water using the example of substantiating the group maximum permissible concentration (MPC) of benzoic acid and its derivatives (sodium benzoate, potassium benzoate and benzyl alcohol). The purpose of the study is to substantiate the group MPC of benzoic acid and its derivatives (sodium benzoate, potassium benzoate and benzyl alcohol) in water, taking into account current data on their toxicity and new methodological approaches to the existing system of hygienic regulation of chemicals in water. Material and methods. The research material was Russian and foreign regulatory and methodological documents, domestic and foreign scientific publications containing information on the physicochemical properties, biotransformation and bioaccumulation abilities, and the effects of benzoic acid and its derivatives on laboratory animals and humans. The research was searched using the databases of scientific literature MedLine/PubMed/PubChem, Scopus, eLIBRARY.ru, WATERTOX databases (RAMS. STC: 02296014904). Research methods included searching and sorting information, identifying common and distinct signs of substance toxicity, comparative analysis, and expert evaluation. Results. The threshold concentration of benzoic acid and its derivatives (sodium benzoate, potassium benzoate, benzyl alcohol) for the effect on the organoleptic properties of water (TCorg.) is 6.0 mg/l (for benzoic acid). The threshold concentration by influence on the processes of self-purification of water bodies (TCsan.) to justify the group MPC of benzoic acid and its derivatives is 0.1 mg/l (for benzoic acid). The value (calculated) of the maximum no-effect concentration of benzoic acid and its derivatives according to the sanitary-toxicological indicator of harmfulness is 20 mg/l (for benzoic acid). Limitations. There is limited data in the literature on the parameters of toxicometry of benzoic acid and its derivatives (sodium benzoate, potassium benzoate, benzyl alcohol). Conclusion. To introduce a group standard for benzoic acid and its derivatives (sodium benzoate, potassium benzoate, benzyl alcohol): 1) for water bodies of domestic and drinking water, cultural and household water use 0.1 mg/l (for benzoic acid), hazard class 3, limiting harm index – general sanitary; 2) for centralized water supply systems, including hot water supply, and non-centralized water supply 6 mg/l (for benzoic acid), hazard class 3, limiting harm index – organoleptic. Based on the principle of “unity of the standard and the method of its control”, to ensure the group PAC of benzoic acid and its derivatives, use the method of determining benzoic acid in water.