The levels of 11 organochlorine pesticides were analyzed in samples of two fish species (Sarotherodon mossambicus and Cichlasoma managüense) and sediments. Due to a toxaphene-producing factory located on the shore of Lake Xolotlán, toxaphene was detected in more than 80% of the fish specimens and in all the sediment samples analyzed. α-BHC, heptachlor, heptachlor-epoxide, aldrin and dieldrin were detected neither in fish nor in sediment samples. DDT or its metabolites DDE or DDD (∊DDT) were present in almost all the fish and sediment samples but in low concentrations. The presence of β-BHC and lindane (τ-BHC) in fish and lindane in sediment was insignificant.
International Journal of Environmental Analytical Chemistry, 1993, Vol 53, Issue 4, p. 297-305