微山湖水体中有机氯农药的分布及风险评价

目的]研究微山湖水体中有机氯农药残留的现状,为微山湖生态评价提供依据。方法]采用气相色谱毛细管柱程序升温,ECD检测器,定量测定底泥和水体中有机氯的含量,并对结果进行分析。结果]微山湖表层沉积物和上覆水样品中有机氯农药总的浓度分别为0.065～0.338ng/ml和8.40～17.62ng/g,六六六、DDT在多数采样点都有检出,有机氯农药含量较多的化合物类有P,P′-DDE、β-HCH和δ-HCH,属低污染水平;微山湖沉积物和上覆水中α-HCH/γ-HCH的比值均小于等于1,而DDT的比值均在1以上,表明微山湖农药主要来源于早期输入。结论]微山湖中的残留农药主要来源于早期输入;利用水生环境沉积物化学品风险评价标准对微山湖水体的有机氯农药的风险评价表明,微山湖沉积物中有机氯农药的含量属于低生态风险水平。

Research on the Distribution of Organochlorine Pesticide in the Weishan Lake and Its Risk Evaluation

Objective] The reference for the ecological evaluation of the Weishan Lake was provided through the research on the current situation of resident of the organochlorine from pesticides its water-body.Method] The content of the organochlorine in the sediment and water-body of the Lake was quantitatively tested with the gas chromatography coupled by ECD detector(GC-ECD) and then the testing data was analyzed.Results] Total level range of OPCS in the samples from its sediment and water-body was 0.065～0.338 ng/ml and 8.40～17.62 ng/g,respectively.The content of pesticide-Liuliuliu and Diditi component was found in most samples.It was also found there were the chemical compound:P,P′-DDE,β-HCH and δ-HCH,which was mostly used in pesticide,belonging to low level of pollution in the Lake.The ratio of α-HCH/γ-HCH in the sediment and water-body of the Lake was less than 1 and DDT,more than 1,indicating that the pollution of pesticide in the Lake was due to the water importation in early period.Conclusion] The water importation in early period resulted in the pollution of pesticide to the Weishan Lake.The risk evaluation of the pollution to the Lake based on the analysis of resident component from the pesticides showed that the content of the organochlorine in its sediment was in a low risk level.