Mansingh, Ajai; Robinson, Dwight E.; Henry, C.; Lawrence, V.
Author Affiliation, Ana.
Natural Products Institute
Pesticide contamination of Jamaican environment II: Insecticide residues in the rivers and shrimps of Rio Cobre Basin, 1982-1996
Environmental Monitoring and Assessment
Date of Publication
Only organochlorine (OC) residues were monitored by gas chromatography in water, sediment and shrimp samples collected every month between July 1982 and August 1983 from the rivers of Rio Cobre basin. In samples collected every four months during 1989-1990, and seven times during July 1995-March 1996, OC and OP (organophosphates) residues were monitored. Carbamate and pyrethroid residues were not monitored. The detection of residues in 1982-1983 was 54 to 100% in water and sediment, and 83 to 100% in shrimp samples from various sampling stations in the four rivers. In other years, it ranged from about 40 to 100% in the three types of samples. In 1982 -1983, DDE and dieldrin residues were found to be much higher than those of lindane and alpha - and beta -endosulfan in Black River, Rio Pedro, Thomas River and Rio Cobre in the watershed. The ranges of means of each residue in water ( mu g L super(-1)), sediment (ng g super(-1)) and shrimp (ng g super(-1)) samples, respectively, were: DDE, 0.059-102.0, 3.44-13.97, 0.344-14.57; dieldrin, 0.026-173.6, 1.21-2.75, 0.427-5.59; alpha -endosulfan, bdl, 1.75-4.00, bdl; beta -endosulfan, bdl (below detectable limits), 2.51-9.48, bdl; and lindane, (bdl), 0.110-0.319, 2.90. In 1989-1990 and 1995-1996, residues of six OCs and two OPs were detected quite regularly. DDE, dieldrin and Chlorpyrifos residues were much higher than those of the other insecticides. The range of their means in water ( mu g L super(-1)), sediment and shrimp (ng g super(-1)), respectively, were: DDE, 1.66-19.76, 0.941-5.84, 1.11-8.32; dieldrin, 0.077-7.22, 0.425-3.31, 0.385-1.59; alpha -endosulfan, 0.034-1.25, 0.021-1.22, 0.032-3.62; beta -endosulfan, 0.665-1.23, 0.008-3.60, 0.005-3.97; endosulfan sulphate, 0.959-1.34, 0.035-3.08, 0.012-1.80; lindane, bdl, 0.005-0.82, 1.19-1.56; chlorpyrifos, 0.702-4.06, 0.005-1.51, 0.156-7.04; and diazinon, bdl, 0-0.150, 0.001-0.006. At the mouth of the river, where it discharges into the sea, the levels of almost all the residues were higher than upstream.....