Levels and distribution of Dechlorane Plus in coastal sediments of the Yellow Sea, North China.

Dechlorane Plus (DP) has been determined in surface sediments from three Chinese coastal bays, e.g. Jiaozhou, Sishili and Taozi Bay in North China. DP concentrations ranged from <1.2 to 187 pg g(-1) dry weight (dw) (mean: 24.7 pg g(-1)dw) in Jiaozhou Bay, <1.2 to 135 pg g(-1)dw (mean 69.9 pg g(-1)dw) in Sishili Bay and <1.2 to 66.7 pg g(-1)dw (mean: 40.4 pg g(-1)dw) in Taozi Bay, respectively. Additionally, two dechlorinated species were quantified, which accounted for 0.6-5.1% of the ∑DP concentration. The f(syn) values (syn-isomer/(syn-+anti-isomer)) in sediments from Jiaozhou Bay (mean 0.29) were close to the technical DP mixture (0.2-0.4), probably indicating local inputs of DP. In contrast, sediments in Sishili and Taozi Bay showed much lower f(syn) values (mean 0.16). During transportation the DP isomers are subject to stereo selective degradation which partly resulted in the relative enrichment of anti-DP in coastal sediments.