Accumulation of Heavy Metals in the Surface Water of Asthamudi Lake, Kollam, Kerala

Ashtamudi Lake, the Ramsar site, is subjected to severe pollution by domestic sewage, agricultural activity and industrial wastes. In this study, the distribution of heavy metals (Fe, Cu, Pb, Zn, Cr, Cd) was measured from three sites of the lake for a period of one year from November 2010 to December 2011. The results of the study show that the heavy metal concentration was remarkably high, especially in Site-2 and Site-3. Iron was found to exceed the maximum permissible limit in all the sites which indicates the severity of pollution in the lake. Chromium exceeds the limit in Site-2 and Site-3, whereas all other metals are within the permissible limit. Constant monitoring of water quality of Ashtamudi Lake is needed to record any fluctuation in the quality and mitigate occurrence of health disorders and the harmful impacts on the aquatic system.