ABSTRACT
The aim of this study was to determine the presence of pesticide residues hexachloro-cyclohexane, cyclodiene, diphenylaliphate and their metabolites in the milk of women from different regions of Karachi, Sindh-Pakistan. An experimental study. This study was conducted in the department of Zoology, University of Karachi from April 2009 to April 2011. A total of 30 human breast milk samples were collected from the Gynae wards of Karachi hospitals. A breast pump was used to collect 5 ml milk sample from each women. The sample was taken in the sterilized and labeled vials. The collected samples were then stored at -20°C for analysis. All the samples were analyzed for the presence of pesticide residues. Samples of milk were prepared accordingly and the purified samples injected into the Shimadzu GC-ECD apparatus. The peaks of the samples were compared by the retention time of the standard peaks. The chromatogram obtained indicated the quantity of pesticide residues. The standard chromatogram of organochlorine pesticides and their isomers were prepared and analyzed on GC-ECD. The standard chromatograms were then matched with the chromatogram of milk samples. The isomers like alpha, beta, gamma and delta were detected as major residues of HCH. The cyclodiene compounds such as aldrin and alpha- endosulfan were detected as common compounds. DDT was found in 43% of milk samples. The percentage of cyclodiene residues was higher than HCH and diphenylaliphate. A significant bioconcentration of organochlorine residues was found in the breast milk. Total DDT concentrations were found higher than total HCH levels. It is thus concluded that this bioconcentration of pesticide residues clearly indicates that the mother contains a heavy amounts of such toxic chemicals