Organochlorine pesticide in fresh and pasteurized cow's milk from Kampala markets

Fresh and pasteurized milk samples from Kampala markets were analyzed for organochlorine pesticides using a gas chromatograph equipped with an electron capture detector. Five organochlorine pesticides, namely; aldrin, dieldrin, endosulfan, lindane, DDT and its metabolites were detected in the milk samples and confirmed with a gas chromatograph equipped with a mass spectrometer [GC-MS]. The mean values are expressed in mgkg(-1) milk fat (mf) basis. The mean concentration in the fresh milk (n=54) were: 0.026 ± 0.003 mg kg(-1) mf; 0.002 ± 0.0003 mg kg(-1), below the detection limit; 0.007 ± 0.003 mg kg(-1), 0.009 ± 0.002 mg kg(-1) milk fat for lindane, endosulfan dieldrin and aldrin, respectively. The mean concentrations of p,p'-DDE; p,p'-DDT and o,p'-DDT were 0.009 ± 0.002 mg kg(-1); 0.033 ± 0.007 mg kg(-1) and 0.008 ± 0.001 mg kg(-1) mf, respectively in the fresh milk samples. In the pasteurized milk samples (n=47), the mean concentrations recorded were: 0.008 ± 0.003 mg kg(-1), 0.025 ± 0.004 mg kg(-1), and 0.007 ± 0.001 mg kg(-1), respectively for p,p'-DDE; p,p'-DDT and o,p'-DDT. Alpha and beta-endosulfan recorded the concentration below the detection limit and the mean of 0.022 ± 0.001 mg kg(-1) mf, 0.005 ± 0.002 mg kg(-1) mf, and 0.006 ± 0.0002 mg kg(-1) mf, respectively for lindane, dieldrin and aldrin. Although, most of the residues detected were above the residue limits set by the FAO/WHO (2008), bioaccumulation of these residues is likely to pose health risks to the consumers of milk in Uganda.