On assessing potential risk of damage to health when dealing with water collection and purification and probability of its occurrence

The paper dwells on the assessment of potential health risk (R1) that can occur in the sphere of water collection and purification. It was shown that activities related to water collection and purification held the leading place (6.10 • 10-3) as per Rlaverage in the priority group "Activities in the sphere of public healthcare, provision of communal, social, and private services" (30.9 %). A share of juridical persons and private entrepreneurs whose activities were ranked as having the 1st and 2nd hazard degree as per health risks amounted to 36 % of all the economic entities who provide water collection and purification for drinking water supply system in the RF regions. Our research object was a typical juridical person that provided a large settlement (more than 19,000 thousand people living there) with drinking water taken from a surface source. Water chlorination is a necessary stage in the technological process of water treatment. Chlorinated organic admixtures are detected in drinking water in concentrations which reach up to 1.3 MPC. The object is ranked as having the 1st hazard degree as per health risk (R1 = 2.98 • 10-3). We quantitatively assessed damage to children's health caused by activities performed by the examined economic entity. We found out that oral introduction of chlorinated organic compounds and their additive effects caused increased non-carcinogenic risk that had the following hazard indexes: functional disorders in the liver HI 1.74: in the kidneys, HI 1.72; in the neuroendocrine system (HI 1.56); in the central nervous system, HI 1.55; the circulatory system, HI 1.48. Chloroform makes the greatest contribution into the hazard index value (up to 99.75 %). In-depth research proved there was damage to health of 33 % of the examined children. Damage was estimated as mild in 84 % cases, and as moderate, in 16% cases. Given the gravity of negative outcomes for health, risk realization amounted to approximately 6.5 % of the calculated value of potential risk Rl for children. It means more than 5,400 additional morbidity cases occur annually at the population level; they are digestive organs diseases, nervous, endocrine, and urinary system diseases. Economic losses amounted to more than 100 million rubles. The authors applied a system of parameterized models that describe cause-and-effect relationships for children population to determine reference chloroform concentrations; they amounted to 0.0031 mg/dm3 in blood; 0.07 mg/dm3, in drinking water; reference dose load amounted to 0.0095 mg/(kg • day).