Analysis of HCHs and DDTs in a sediment core from the Old Yellow River Estuary, China

The present study analyzed the distribution of HCHs and DDTs in a sediment core from the Old Yellow River Estuary, China. The OCP levels were detected by Soxhlet extraction followed by gas chromatography (GC) using a mass-selective detector. Sediment age was analyzed for Pb-210 using an Ortec GWL HPGe gamma spectrometer. The results indicated that the concentrations of Sigma DDT in the sediment core were much lower than those of Sigma HCH. Compared with the other estuarine and coastal regions in Chinese rivers, HCHs levels in this area were higher or similar, while DDTs levels were lower. The compositional analysis indicated that beta-HCH and p, p'-DOD were the predominant species. The temporal trends indicated that levels of HCHs and DDTs were related with their historical usage, emission and soil residues. According to the analysis of the ratio, HCHs in this area was mainly due to the technical historical residue and recent lindane. DDTs was mainly due to historical residue. The biodegradation conditions for DDTs were anaerobic. The dicofol-type DDTs application occurred in this area. Crown Copyright (C) 2013 Published by Elsevier Inc. All rights reserved.