Organochlorine pesticide residues in dairy products in Jordan

Abstract

The use of aldrin, dieldrin, endrin, heptachlor and hexachlorobenzene (HCB) has been banned in Jordan officially in 1981, and of dichlorodiphenyltrichloroethane (DDT) in 1995. However, residues of such compounds can still be found in the environment and in foodstuffs. Dairy products are an important exposure route for organochlorine pesticides (OCPs) to humans. For this reason, the presence of OCP residues in 233 dairy product samples; comprising milk, butter, cheese, labaneh and yoghurt collected from Jordan was determined. All samples were analyzed for their residual contents of aldrin, DDT and metabolites (DDTs), dieldrin, endosulfan isomers, endrin, hexachlorocyclohexane isomers (HCHs), heptachlor and HCB. Levels of these compounds were determined by gas chromatography with electron capture detector (GC-ECD). The results indicated that 9% (21/233), 8.5% (20/233), 6% (14/233) and 2.1% (5/233) of the examined samples were contaminated with β-HCH, pp′-DDE, α-HCH and γ-HCH, respectively. Heptachlor and α-endosulfan were only present in less than 2% of the analyzed samples. None of the samples revealed the presence of aldrin, op′-DDD, pp′-DDD, op′-DDE, op′-DDT, pp′-DDT, dieldrin, β-endosulfan, endrin and HCB at their detection limits. The order for the contamination in the analyzed dairy products was labaneh > cheese > yoghurt > butter > milk. This study has provided the preliminary information on the concentration of OCPs in dairy products for the first time in Jordan. The results will help in a scientific assessment of the implications of pesticide residues with regards to human risks in Jordan.