鄱阳湖流域沉积物中有机氯农药的残留特征及风险评估

采用GC/ECD分析了鄱阳湖流域沉积物中有机氯农药的残留特征及生态风险,结果表明:所测样品中有机氯农药浓度范围为1.22～32.19 ng/g,其中,六六六(HCHs)、滴滴涕(DDTs)、六氯苯(HCB)在几乎所有采样点都有检出,含量分别是未检出～12.95 ng/g、0.75～12.57ng/g、未检出～10.8.所测样品中大部分W_(DDT)/(W_(DDE)+W_(DDD))>1,表明有新的DDT输入,HCHs主要为长时间降解后的农药残留.鄱阳湖流域沉积物中DDT、DDD和DDE含量绝大部分小于风险评估中值(ERM),但接近一半介于风险评估低值(ERL)和ERM之间,而且有一个点大于ERM,表明其生态风险大多介于10%～50%,但有一个点的生态风险大于50%.

Organochlorine Residues in Sediments From Poyang Lake Basin and Their Risk Evaluation

Organochlorine residues in sediments from Poyang Lake Basin and reservoirs and their risk evaluation were presented in the paper.Organochlorine contents in the surface sediment samples taken from Poyang Lake Basin were measured by GC/ECD.The following results were obtained:1) The total concentrations of organochlorine pesticides determined in the samples were 1.22～32.19 ng/g in which HCHs、DDTs and HCB were detected in almost all samples; their concentrations were ND～12.95 ng/g、0.75～12.57ng/g and ND～10.83.2) The ratios of wDDT to (wDDD +wDDE ) were larger than 1 in most of samples,showing that there were new DDT inputs.The concentration of the HCHs were dominant in the HCHs in all samples.3) Most of the residues of DDT、DDD and DDE in all sediment samples were lower than the Effects Range-Median (ERM).However,half of them were between ERL and ERM,showing the ecological risks for most of them were between 10% and 50%.But the residues of DDT the four sample was higher than ERM,showing the ecological risk for it was higher than 50%.