Persistence and fate of some Organophosphorus pesticides in sea-sediments along east coast of India

Abstract

Stability and fate of pesticides, monocrotophos, phosphamidon and DDVP, were studied in sediment samples collected along the east coast of India. <i>p</i>H, salinity and exchangeable cations present in sediments exhibited profound influence on stability and fate of these pesticides. Rate of hydrolysis of these pesticides in freshwater, brackish water and sea-sediments followed the path of pseudo first order reaction. The rate constants (<i>K</i>₁) and the half life periods (<i>T</i><img src='http://www.niscair.res.in/jinfo/1bytwo.gif' border=0>) of these pesticides were determined in freshwater, brackishwater and sea-sediments with and without the presence of all exchangeable actions and anions. The low stability of these pesticides in the sea-sediments indicates that the major elements, present in the sea-sediments as cations have reduced the toxic effects of these pesticides to the marine organisms.