Gas chromatographic analysis of organochlorine pesticides in Lake Anasagar of Ajmer, Rajasthan (India).

Anasagar is a perennial, shallow fresh water body which is degraded because of agricultural and other anthropogenic activities, such as input of detergent, sewage disposal, human settlement around the lake etc. In the lake waters as well as in the catchment area, pesticides are being used by the farmers which lead to contamination of water. Gas chromatographic analysis of 120 contaminated water samples collected from the lake was carried out. The organochlorine pesticides recorded in the samples were Heptachlor, beta-HCH, gamma-HCH, Aldrin, DDT and Endosulfan. The average ranges of these pesticides were 0.0224 ppm, 0.1035 ppm, 0.0478 ppm, 0.0041 ppm, 0.1381 ppm and 0.5051 ppm, respectively. The study revealed that water of Anasagar is highly contaminated with these synthetic pesticides. Among these agrochemicals, the level of Endosulfan, DDT and Y-HCH were found to be significantly high in the lake. Therefore, the research efforts are needed to conserve the wetland as well as to minimise the impacts of agrochemicals on the lake ecosystem.