ENVIRONMENTAL AND HYGIENIC ASSESSMENT OF NITRATE ENTRY INTO THE HUMAN BODY WITH DRINKING WATER

Abstract

The article raises the issue of compliance of water from the sources of centralized and decentralized water supply in Ukraine and the Cherkasy region with the requirements of DSanPiN 2.2.4-171-10 "Hygienic requirements for drinking water intended for human consumption", the Law of Ukraine "On drinking water and drinking water supply", "On ensuring sanitary and epidemic welfare". The results of the research of the nitrate content in centralized water mains, private wells and wells in settlements of the Cherkasy district are highlighted. It is established that the average concentration of nitrates in the water of centralized water supply sources was 24 mg/dm3, which does not exceed the maximum permissible standard. However, in 2.8% of the investigated water samples of centralized water supply sources, a slight excess of the normative values was observed, and in the water of individual sources it was 110 mg/dm3 (the city of Uman, the city of Talne, etc.). The determined average concentration of nitrates in the water of decentralized water supply sources was 44 mg/dm3, which is within the maximum permissible level, but in 18% of the tested samples there was a deviation from the permissible daily dose (PDD – 50 mg/dm3) in 1,5–4, 0 times, and, in some sources of control (mines and tube wells), was 235 mg/dm3 and even 900 mg/dm3, which is extremely dangerous for public health, especially for infants, for whom the daily norm is 2,5 mg /kg/day. The issue of the effect of nitrate compounds on the human body, which in high doses quickly oxidize blood hemoglobin into methemoglobin, causing circulatory and tissue hypoxia, block the enzyme systems of body cells, which leads to a violation of oxidative phosphorylation and nitrate methemoglobinemia, has been studied. Possible sources of ingress of toxicants into drinking water have been determined, and recommendations for its use have been developed.