Organochlorine pesticides in sediments from Gulfs of Naples and Salerno, Southern Italy

Organochlorine pesticides (OCPs) have the potential to concentrate in the marine environment and threaten the local marine life. Here, we present the results of a study of the contamination profiles, spatial distribution, possible sources, and potential ecological risk of OCPs in marine sediments from Gulfs of Naples and Salerno, Southern Italy. The total concentrations of OCPs ranged from 0.54 to 99.6 ng/g (average mean: AM = 7.80 +/- 16.3 ng/g). The concentration of OCPs from gulf of Salerno (AM = 9.20 +/- 20.7 ng/g) was higher than Naples (AM = 7.49 +/- 15.3 ng/g). The sediment levels of individual OCPs were (in sequence of concentration) dichlorodiphenyltrichloroethanes (DDTs, including p,p'-DDD, p,p'-DDE, o,p'-DDT and p,p'-DDT) > CHLs (heptachlor, heptachlor epoxide, trans-chlordane, and cis-chlordane) > hexachlorocyclohexanes (HCHs, including alpha-beta-gamma-and delta-HCH) > DRINs (aldrin, dieldrin, and endrin) > hexachlorobenzene (HCB) > SULPHs (alpha-endosulfan, beta-endosulfan, and endosulfan sulfate). DDTs and heptachlor were the highest in proportion among the OCPs. High concentrations of OCPs were observed in the coastal area especially near the cities of Naples and Salerno as a result of terrigenous supply. The occurrence of high residual levels of OCPs found in this study may be attributed to their historical application. Marine dynamics influence the distribution of OCPs, in particular the HCHs, as they are less lipophilic and more soluble. According to established sediment quality guidelines, DDTs may cause ecological risk.