MATERIALS FOR THE SUBSTANTIATION OF HYGIENIC STANDARD OF MICROCYSTIN-LR IN WATER OF WATER OBJECTS

Introduction. The growth of the anthropogenic pollution of water bodies and the regulation of river flow has led to an almost universal intensification of eutrophication of water bodies, which contributes to the mass development (“blooming “) in the summer cyanobacteria - blue-green algae. The main danger of “ blooming “ is the ability of cyanobacteria to produce toxins to adversely affect human health, among which hepatotoxin microcystin-LR takes the first place in prevalence and toxicity. To date, microcystin-LR in drinking water is regulated by WHO and 22 States, but in Russia, microcystin-LR in water is not standardized. The purpose of this work is to substantiate the MAC of microcystin-LR in water of water bodies and drinking water of the Russian Federation. Material and methods. The data of the world practice of the toxicity assessment of microcystin-LR, including the acute and chronic effects of microcystin-LR on animals and humans in natural conditions; the results of the study of acute, subacute and chronic toxic effects, effects on reproductive function, mutagenic, genotoxic and carcinogenic effects in experiments on laboratory animals were analyzed. The methodology of substantiation and harmonization of hygienic standards of substances in water was used. Results. Analysis of the information about the toxic effect of microcystin-LR, the experience of WHO and 22 countries on the regulation of its permissible content in water, as well as domestic experience of justification and harmonization of hygienic standards makes it possible to recommend the MAC microcystin-LR in water of water bodies and drinking water at the level of 0.001 mg/l marked “k” (carcinogen), 1st hazard class, limiting harmfulness index - sanitary-toxicological. Discussion. The results of the study showed that to justify the MAC of microcystin-LR in water, one index of harmfulness is sufficient - sanitary-toxicological, the study of the effect on organoleptic and general sanitary indices is not advisable because of the specific properties of the toxin. Conclusion. In the conditions of non-decreasing pollution of water bodies with cyanotoxins of blue-green algae, the introduction of MAC microcystin-LR will be important for the prevention of its adverse effects on public health.