全氟辛烷磺酸短期暴露对不同作物苗期生长的影响

全氟辛烷磺酸(PFOS)作为一种新型持久性有机污染物，目前国内外对其生态毒性研究主要集中在水环境领域，而高等植物的生态毒性数据尚不完善。因此，本研究采用内培养方式，选取小麦、大麦、小白菜、三叶草、绿豆作为供试植物，利用根伸长、芽伸长、地上部分生物量等评价指标，研究了PFOS短期暴露对不同供试作物苗期生长的影响，建立了PFOS和作物苗期生长的剂量-效应关系，并对不同的评价指标进行相关性分析，筛选出表征PFOS生态毒性的敏感植物。结果表明，不同供试作物培育3 d后，PFOS对其于不同毒性终点的最小EC₅₀值为：小麦352 mg·kg^-1(根伸长)、大麦434 mg·kg^-1(根伸长)、三叶草794 mg·kg^-1(地上部分生物量鲜重)、小白菜829 mg·kg^-1(地上部分生物量鲜重)、绿豆>1 000 mg·kg^-1，因此敏感程度依次为：小麦>大麦>三叶草>小白菜>绿豆。须根系作物小麦、大麦较直根系作物三叶草、小白菜和绿豆敏感，而须根系作物各评价指标的敏感程度依次为：根伸长>地上部分生物量鲜重>芽伸长>地上部分生物量干重，可见小麦的根伸长对PFOS污染最为敏感。各评价指标间均呈正相关关系，表明PFOS对同种植物的不同评价指标影响趋势一致。

Influence of Short-Term Exposure of PFOS on Seedling Growth of Different Plants

PFOS is a new type of persistent organic pollutants (POPs) and most of its ecotoxiciy tests were focused on the aquatic system. The research on phytotoxicity of PFOS is still limited. The aim of this paper is to investigate the influence of short-term exposure of PFOS on seedling growth of several different plants including wheat, barley, Chinese cabbage, clover and mung bean. The root elongation, shoot elongation and the above ground biomass were selected as different evaluation indices. The dose-response relationship between PFOS concentration and crop growth was established and the correlation was analyzed between different indices, aiming to screen out the plant which was most sensitive to PFOS contamination. Results showed that the lowest EC₅₀ for different endpoints for the selected crops were: wheat 352 mg·kg^-1 (root elongation), barley 434 mg·kg^-1 (root elongation), clover 794 mg·kg^-1 (fresh weight of the above ground biomass), cabbage 829 mg·kg^-1 (fresh weight of the above ground biomass), mung bean >1 000 mg·kg^-1. Thus the decreasing order of phytotoxicity of PFOS for the selected crops were: wheat > barley > clover >cabbage > mung bean. Fibrous root crops (wheat and barley) were more sensitive than straight root crops (clover, cabbage and mung bean). The descending order of sensitivity for four evaluation indices was root elongation > fresh weight of the above ground biomass > shoot elongation > dry weight of the above ground biomass. The root elongation of wheat was the most sensitive indicator. The evaluation indices were positively related based on correlation analysis, indicating PFOS has identical influence on the different evaluation indices for each kind of plant.