Occurrence and Risk Assessment of Organochlorine Pesticides (OCPs) in Surface Water of Veeranam Lake, Tamil Nadu

The study aimed at assessing the levels of organochlorine pesticide (OCPs) residues in the surface water of Veeranam Lake, Tamil Nadu, South India and its effects on human beings and aquatic organisms. Pesticide residues were quantified using Gas Chromatograph Mass Spectrometer (GCMS) in Quadrupole analyzer on Electron Ionization (EI) mode. The measured environmental concentration (MEC) of OCPs in the water samples was taken for calculating the carcinogenic risk and ecological risk quotient (ErQ). The most commonly encountered organochlorine pesticides (OCPs) in surface water of Veeranam Lake were isomers of DDT (p, p?-DDD & o, p?-DDT) and HCH (? & ?) compounds, aldrin, dieldrin and mirex. The mean concentrations of endrin exceed the permissible limit of Canadian guidelines for fresh water (CGFW). The results of the present investigation showed that the carcinogenic risk among local population through intake of water from Veeranam Lake is more likely due to presence of significant levels of aldrin and mirex. The result also demonstrated acute risk to aquatic animals as a result of high concentrations of aldrin and endrin. Even though the incidence percentage of DDT (p, p?-DDD & o, p?-DDT), HCH (? & ?), aldrin, dieldrin and mirex were high, their mean concentrations are well below the international permissible limit (CGFW) except endrin. However, these minimal levels of aldrin and mirex were supposed to cause carcinogenic risk and ecological risk to humans and aquatic organisms respectively.