MONITORING INVESTIGATIONS OF SON-KUL LAKE (KYRGYZSTAN) POLLUTED BY PESTICIDES
The results of environmental monitoring of Son-Kul Lake (Kyrgyzstan), conducted in 2017-2018 by representatives of environmental non-governmental public organizations with the participation of the Kyrgyz Republic state environmental laboratory and international water quality monitoring experts, are presented, which have been used for giving recommendations for organizing the lake monitoring system. The monitoring was aimed at determining the lake ecological status and further specifying the ways of its sustainable management, including its decontamination from hazardous chemical compounds and solid waste accumulated as a result of pesticide pollution and fishing activities, respectively. The monitoring analyzed the content of a wide range of pesticides in the lake surface water samples, bottom sediments, as well as in fish inhabitants. A series of persistent organic pollutants (POPs), i.e. 4,4'-dichlorodiphenyltrichloroethane (DDT), hexachlorocyclohexane isomers, polychlorinated biphenyls, and other hazardous chemical compounds were found in collected samples. The observed levels of POPs in the bottom sediments and fish samples were within the limited range, while the analysis of water samples showed an exceeding of the maximum permissible concentrations for DDT and hexachlorocyclohexane for fishery waters. The obtained preliminary results show an urgent need to develop a state monitoring program for Son-Kul Lake and to conduct a continuous monitoring on POPs levels.