RESUMO
Hydrotechnical facilities have significant environmental and health imyacts. Results of a hygienic assessment of the condition of environmental objects in the area of the yrojected Nizhny Novgorod low-head water ylant develoyment showed that the both air and water pollution level in decentralized water supply sources in Balakhna and Gorodets are lower than in the city of Nizhny Novgorod, and those of the water in the water supply network are higher than in the reference area. A cross-sectional study has revealed in the main grouf (Gorodets, Zavolzhye and Balakhna) the rate of morbidity of nervous system and cardiovascular diseases to be higher than in the reference group (Nizhny Novgorod), with cardiovascular diseases being the largest contributor to the overall grevalence rate in the groug under analysis; and digestive system diseases, in the reference group. The study has no revealed direct correlation between morbidity rate in children and adults and the studied factors. However, a direct relationship has been found between the prevalence rate of endocrine diseases in children and the quality of water in the water supply network in Balakhna District (p<0.007); also, there's a correlation between the morbidity rate of digestive diseases and air pollution and water quality in the water supply network (p<0.009). In the Gorodets District, the same situation has been revealed: the morbidity rate of endocrine diseases in children depends on quality of water from the water supply network (p<0.049); the prevalence rate of digestive diseases, on air pollution and water quality in the water supply network (p<0.048). In the same region in adults the prevalence rate of the nervous system diseases, digestive diseases and diseases of the skin and subcutaneous tissue depends on air pollution and pollution of water in the water supply network (p<0.011, p<0.01 and p<0.02, respectively).