Chiang Mai Journal of Science

Five carbamate pesticides, namely, methomyl, benomyl, aldicarb, carbofuran and carbaryl in water were extracted simultaneously by solid phase ENVI-18. The results showed good recoveries in the ranges of 95.57-98.52% by using 4 ml methanol as eluent with the standard deviation of 0.90-2.41. The detection limits of methomyl, benomyl, aldicarb, carbofuran and carbaryl from solid phase extraction were 65, 167, 226, 140 and 188 ng, respectively. Eight organochlorine pesticides, namely, a -BHC, aldrin dieldrin, endrin, heptachlor, heptachlor epoxide, 4,4 DDT and 2,4 DDT were simultaneously extracted by solid phase LC-18 using 5 ml of 15% diethylether in hexane as eluent. The results showed good recoveries in the ranges of 90.04-101.44% with the standard deviation of 0.49-2.61. Heptachlor and aldrin showed low percentage recoveries of 22.60 and 50.55, respectively, due to degradation. The detection limits for solid phase extraction of organochlorine pesticides were in the ranges of 119 - 379 pg.