杭州市内主要河流沉积物中拟除虫菊酯的残留特征及风险

Residue characteristics and risks of pyrethroids in sediments ofmajor rivers in Hangzhou

拟除虫菊酯(Synthetic pyrethroids,SPs)类杀虫剂的广泛使用已成为水生态环境安全关注的重点问题。为探明SPs在杭州主要流域沉积物中的污染特征,选择钱塘江和京杭大运河(杭州段)作为采样流域,采用气相色谱质谱联用仪测定了8个采样点中的联苯菊酯、氯菊酯和主要降解产物3苯氧基苯苄醇的残留特征。结果显示:京杭大运河(杭州段)沉积物中SPs的整体质量分数高于钱塘江,SPs质量分数最高点位于两流域交汇处JF,为11.01 ng/g;两条流域SPs质量分数的最高点分别位于京杭大运河(杭州段)和钱塘江上游的TQ(10.43 ng/g)和WY(6.96 ng/g);3-PBAlc检出水平较低;对鱼类和无脊椎动物的风险评估表明各采样点沉积物中的SPs尚未对采样区域构成明显的水生生态风险。

The widespread use of synthetic pyrethroids(SPs)pesticides has become a key concern for the safety of the water ecosystem.To investigate the pollution characteristics of SPs in the sediments of the main watersheds in Hangzhou,including the Qiantang River and the Beijing-Hangzhou Grand Canal(Hangzhou section),were selected as the sampling watersheds,and the residue characteristics of bifenthrin,permethrin and the main degradation product 3-phenoxybenzyl alcohol(3-PBAlc)in eight sampling sites were determined by gas chromatography-mass spectrometry.The results showed that the overall mass fraction of SPs in the sediments of the Canal were higher than that of the Qiantang River.The highest SPs mass fraction was 11.01 ng/g and located at the confluence of the two basins(JF);the highest mass fraction of SPs in the two basins were placed at the upper reaches of the Canal and the Qiantang River TQ(10.43 ng/g)and WY(6.96 ng/g),respectively.The detection level of 3-PBAlc was low;the risk assessment on fish and invertebrates indicated that SPs in sediment at each sampling region did not present a significant aquatic ecological risk to the sampling area.