Distribution of pesticide (organochlorine) in Terengganu river estuarine sediments

Abstract

Organochlorine pesticide in sediment samples were detected using Gas Chromatography - Electron Capture Detector (GC-ECD).The primary aim of this study is to determine the species of organochlorine pesticide (OCP) and their concentration in Terengganu River Estuarine sediment. The levels of contamination of 16 species organochlorine pesticides such as HCHs, DDTs, aldrin, dieldrin and endrin were determined in estuarine sediments along the Terengganu River Estuary in Terengganu. The concentration of various pesticides in sediments from the mouth of estuaries along the river were in the range of 0.01-1853095 ng/g (alpha-BHC), 0.0021669

ng/g (beta BHC), 0.0002-6048 ng/g (gamma-BHC), 0.0003-2422 ng/g (delta­ BHC), 0.02-17874 ng/g (heptachlor), 0.01 - 49029 ng/g (aldrin), 0.004 - 9565 ng/g (heptachlor epoxide isomer B), 0.002 - 69855 ng/g (endosulfan alpha), 0.01 11679280 ng/g (dieldrin), 0.15 - 5972 ng/g (DDE), 0.28 - 8428 ng/g (endrin), 0.42 1899 (endosulfan beta), 0.47 - 24132 ng/g (DOD), 0.5 - 2484 ng/g (endrin aldehyde), 0.14 - 4652 ng/g (endosulfan sulfate) and 21.5 - 29006 ng/g (DDT). Among the organochlorine pesticides, dieldrin and gamma-BHC were most dominant in the estuarine sediments. The highest concentration of dieldrin was estimated at station 2 near the mouth of Terengganu River estuary (11679280 ng/g) while that of gamma­ BHC at the same station (6048 ng/g). Among the cyclodiene compounds, alpha-BHC was in abundance in most of the sediments whereas DDT could be detected at the smaller river channel.