Scientific substantiation of Maximum Permissible Concentrations (MPCs) for benzoic acid and sodium benzoate in water based on modern data (literature review)

Abstract

Correction of outdated MPCs for substances in water should be based on a generalization of the results of previous studies and the new literature data. On the example of benzoic acid and sodium benzoate, which are widespread in the environment, the possibility of adjusting the current MPC in water according to literature data is considered. A comparative assessment of the methods for calculating the MPC following international approaches and practices adopted in Russia are given. The internationally set maximum allowable dose (MAD) is based on data that does not comply with Organization for Economic Cooperation and Development (OECD) requirements or domestic regulations. Modern works present new data on the mechanisms and manifestations of the harmful effects of benzoic acid and sodium benzoate. These data indicate the multipathogenetic representation of the toxic effect of benzoic acid, which is typical for most chemical compounds. The results of experiments on animals showed benzoic acid and sodium benzoate to harm the central nervous system. In particular, they significantly impair memory and coordination of movements. A forecast of safe levels of benzoic acid and sodium benzoate was carried out based on two approaches - determination of MPC in water according to the internationally established allowable daily intake (ADI) according to international requirements (1.7 mg/l) and calculation based on experimental data following the requirements of domestic methodological documents (0.6 mg/l). The toxicity of benzoic acid and sodium benzoate is determined by the benzoate ion, which makes it possible to recommend a single standard for two compounds at the level of 0.6 mg/l, a sanitary and toxicological hazard index, hazard class 2. When considering the possibility and ways of harmonizing the methodology for the regulation of substances in water with international approaches, it is necessary to take into account the deep research of scientists of our country concerning the accumulation of the effect of intoxication with prolonged exposure to substances on the body, adaptation responses, and disruption of adaptive responses and the development of new responses over time.