Insecticide contamination of Jamaican environment. V. Island-wide rapid survey of residues in surface and ground water

Residues of organochlorines and organophosphates were determined by gas chr omatography in water and sediment from 26 locations in 17 major rivers, 7 n atural springs and 13 wells across Jamaica. Samples were collected on only one occasion between May and July, 1994. Residues of endosulfan were detect ed in all but three rivers; alpha-endosulfan in 15 samples of sediment (0.9 -108.1, mean = 28.93, S.E. = 7.198 mu g kg(-1)) and 13 of water (0.01-0.35, mean = 0.11, S.E. = 0.035 mu g L-1), beta-endosulfan in 5 sediment (15.29- 49.35, mean = 30.56, S.E. = 7.132 mu g kg(-1)) and 12 water (0.05-0.31, mea n = 0.14, S.E. = 0.031 mu g L-1) samples, and endosulfan sulphate in waters of three rivers (0.003-0.244 mu g L-1). Chlorpyrifos was present in 9 sedi ment (0.423-135.2, mean = 18.38, S.E. = 10.699 mu g kg(-1)) and two water ( 0.001-0.022 mu g L-1) samples, diazinon and ethoprophos in the sediment of one river each. Mean levels (mu g L-1) of alpha and beta isomers and sulpha te of endosulfan were 0.16 (S.E. = 0.057), 0.12 (S.E. = 0.036) and 0.15 (S. E. = 0.089), respectively, in four of the seven springs and 0.23 (S.E. = 0. 052), 0.11 (S.E. = 0.029) and 0.26 (S.E. = 0.088), respectively, in seven o f the thirteen wells monitored.