Concentration and Distribution of Organochlorine Pesticides Residues in Surface Sediment from Xiaohai,China

Concentrations of organochlorine pesticides(OCPs) residues in Quanzhou Bay,China,are determined by GC/ECD.The results show that concentrations of total OCPs in the upper surface sediment is obviously higher than those in the lower sediment.It also presents that concentrations of OCPs increase in the inner bay and then decrease near the exit.The sharp high concentration in the exit may be attributed to its special terrain.The result shows that the concentration of DDTs moves up first,and then goes down from the inner bay to the outside,and the sharp ascending concentration is probably relevant to the special terrain of the lagoon.The degree of DDTs degradation in the inner bay is obvious higher than that near the exit.The ratio of α-HCH/γ-HCH is between 0 and 4,and the source of HCHs is industrial HCH.The concentration of DDTs in Xiaohai is lower than that in developed areas,such as Xiamen Bay,and higher than that in half-opened bay,such as Quanzhou Bay and Xinghua Bay.The concentration of HCHs is much lower than that in Xiamen Bay,Quanzhou Bay and Xinghua Bay.