Organochlorine Pesticide Residues in the Muscles of Three Fishes from the Ganges Estuary, Bangladesh

S.M.A. Jabber, Y.S.A. Khan and M.S. Rahman

ABSTRACT

Organochlorine pesticide (OCPs) residues were monitored in muscle samples of Lates calcarifer, Liza subviridis and Cynoglossus cynoglossus collected during October-December (Dry season) 1996 and May-July (Wet season) 1997 from the Ganges estuary. The OCP residues were analysed by Gas-Chromatography (GC) in Electron Capture Detector (ECD) mode and were verified by Thin Layer Chromatography (TLC). OCP residues were more in the muscles of Lates calcarifer because of its carnivorous characteristic, and lowest in Liza subviridis, a herbivorous fish. The OCP residue concentrations were found in order of heptachlor>dieldrin>DDTs>aldrin for Lates calcarifer and in order of DDTs>heptachlor>dieldrin>aldrin for the Cynoglossus cynoglossus. In Liza subviridis only DDTs were found. A good positive linear correlation was observed between the pesticide residues ( DDT and OCPs) and lipid contents of fishes. Among the nine OCP residues analysed only dieldrin and heptachlor residues in Lates calcarifer exceed the FAO/WHO (1993) recommended permissible limit.