Residues and risk assessment of dichlorodiphenyl trichloroethanes in commercial fishes from Dongguan and its adjacent waters

We determined the residues of dichlorodiphenyl trichloroethanes (DDTs) in 6 species of commercial fishes from Dongguan and its adjacent waters by Agilent 7890N GC, capillary column (HP-5 30 m250 m0.25 m) and ECD detector. Results show that the DDTs residues in those fishes are 1.527~24.842 gkg-1. Coilia mystus has the highest content of DDTs residues, followed by Uroconger lepturus and Harpadon nehereus. The average content of P,P'-DDE, P,P'-DDD, P,P'-DDT and O,P'-DDT is 44.55%, 29.19%, 22.01% and 4.25%, respectively. Since no new pollution source of DDTs was found, the DDTs in those fishes might come from the past pollution and pose no significant threat to human health.