He Wenxiang, Megharaj Mallavarapu, Naidu Ravi
College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, 712100, People's Republic of China.
Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, Australia.
Environ Monit Assess. 2016 Jul;188(7):424. doi: 10.1007/s10661-016-5416-y. Epub 2016 Jun 21.
Perfluorooctanoic acid (PFOA) is a widespread persistent organic contaminant in the environment that has recently raised much of regulatory and public concern. Therefore, assessment of its ecological risk is a top priority research. Hence, this study investigated the toxicity of PFOA to beneficial microbial processes in the soil such as activities of dehydrogenase, urease and potential nitrification in addition to earthworm survival, weight loss and PFOA bioaccumulation in two contrasting soils. In general, PFOA caused inhibition of all the measured microbial processes in a dose-dependent manner and the inhibition was higher in Williamtown (WT) soil than Edinburgh (EB) soil. Thus, WT soil being sandy in nature with low clay content showed higher PFOA bioavailability and hence showed higher toxicity. There was no mortality in earthworms exposed up to 100 mg PFOA/kilogram soil in both the soils; however, there was a significant weight loss from 25 mg/kg onwards. This study clearly demonstrates that soil contamination of PFOA can lead to adverse effects on soil health.
全氟辛酸（PFOA）是环境中一种广泛存在的持久性有机污染物，最近引起了监管部门和公众的广泛关注。因此，评估其生态风险是一项首要的研究任务。因此，本研究调查了PFOA对土壤中有益微生物过程的毒性，如脱氢酶、脲酶活性和潜在硝化作用，以及两种不同土壤中蚯蚓的存活率、体重减轻和PFOA生物累积情况。总体而言，PFOA以剂量依赖的方式抑制了所有测量的微生物过程，并且在威廉敦（WT）土壤中的抑制作用高于爱丁堡（EB）土壤。因此，WT土壤质地为沙质，粘土含量低，显示出较高的PFOA生物可利用性，因此毒性也较高。在两种土壤中，暴露于高达100毫克PFOA/千克土壤的蚯蚓均未死亡；然而，从25毫克/千克起体重出现显著减轻。本研究清楚地表明，PFOA对土壤的污染会对土壤健康产生不利影响。
