黄浦江表层沉积物中有机氯农药的分布特征及风险评价

用双柱GC/ECD对黄浦江表层沉积物中的20种有机氯农药进行了分析 沉积物中总有机氯农药含量范围为2.65～19.54ng/g ,含量较高的组分有DDTs、BHCs、甲氧氯和狄氏剂等,DDTs含量高于BHCs ,含量范围分别为0.68～4.43ng/g和0.14～0.77ng/g 从上游到下游沉积物中有机氯农药含量呈升高趋势,说明工业污染及苏州河对黄浦江中下游水环境中的有机氯农药具有较大的输入贡献.有机氯农药组分分布特征研究表明,当前沉积物中的有机氯农药主要来自于早期残留或是施用农药长期风化后的土壤.相关性分析表明,总有机碳是影响沉积物中有机氯农药分布的重要因素.与其它地区相比较,黄浦江沉积物中有机氯农药含量较低.与沉积物风险评估值相比较,黄浦江中下游沉积物存在一定的生态风险.

Distribution of Organochlorine Pesticides in Surface Sediments from Huangpu River and Its Risk Evaluation

This paper reports 20 organochlorine pesticides (OCPs) in surface sediments of Huangpu River in Shanghai, China. Pesticides were analyzed by GC/ECD with dual column. The concentration range of sigmaOCPs in sediments was 2.65-19.54 ng/g. DDTs, BHCs, methoxychlor and dieldrin had higher concentration than others. The concentration range of DDTs and BHCs was 0.68-4.43 ng/g and 0.14-0.77 ng/g, respectively, which shows concentration of DDTs was higher than BHCs. OCPs content increasing from upper to downstream Huangpu River implicats that discharging of industrial effluents and inflow of Suzhou River offered lots of OCPs to middle-lower Huangpu River. Distribution of OCPs components indicate that OCPs in sediments may be derived from the aged and weathered agricultural soils. According to correlation analysis between OCPs and TOC of sediments, TOC content influences the distribution of OCPs in sediment strongly. Contamination level of OCPs in sediment of Huangpu River is relatively lower than other areas. Comparing with ERL and ERM value of risk evaluation, sediments in middle-lower Huangpu River pose a bit high risk to consumers of bottom feeders.