Global Centre for Environmental Remediation, Faculty of Science, The University of Newcastle, Callaghan, NSW 2308, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, The University of Newcastle, Callaghan, NSW 2308, Australia.
Global Centre for Environmental Remediation, Faculty of Science, The University of Newcastle, Callaghan, NSW 2308, Australia.
Sci Total Environ. 2021 May 15;769:144577. doi: 10.1016/j.scitotenv.2020.144577. Epub 2021 Jan 9.
Widespread environmental contamination of per- and polyfluoroalkyl substances (PFAS) is well established. Nevertheless, few studies have reported on the aquatic toxicity of PFAS, especially in indicator species such as Daphnia. In this study, the toxicity of two major PFAS, namely perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS), was investigated on water flea (Daphnia carinata) using a battery of comprehensive toxicity tests, including a 48 h acute and a 21-day chronic assays. The survival, growth, and reproduction of D. carinata were monitored over a 21-day life cycle. PFOS exhibited higher toxicity than PFOA. The 48 h LC values (confidence interval) based on acute toxicity for PFOA and PFOS were 78.2 (54.9-105) mg L and 8.8 (6.4-11.6) mg L, respectively. Chronic exposure to PFOS for 21 days displayed mortality and reproductive defects in D. carinata at a concentration as low as 0.001 mg L. Genotoxicity assessment using comet assay revealed that exposure for 96 h to PFOS at 1 and 10.0 mg L significantly damaged the organism's genetic makeup. The results of this study have great implications for risk assessment of PFOS and PFOA in aquatic ecosystems, given the potential of PFOS to pose a risk to Daphnia even at lower concentrations (1 μg L).
全氟和多氟烷基物质（PFAS）的广泛环境污染已得到充分证实。然而，很少有研究报告 PFAS 的水生毒性，尤其是在水蚤等指示物种中。在这项研究中，使用一系列综合毒性测试研究了两种主要的 PFAS，即全氟辛酸（PFOA）和全氟辛烷磺酸（PFOS）对水蚤（Daphnia carinata）的毒性，包括 48 小时急性毒性和 21 天慢性毒性试验。在 21 天的生命周期中监测了 D. carinata 的生存、生长和繁殖情况。PFOS 的毒性高于 PFOA。基于急性毒性的 48 小时 LC 值（置信区间），PFOA 和 PFOS 的数值分别为 78.2（54.9-105）mg/L 和 8.8（6.4-11.6）mg/L。慢性暴露于 21 天 PFOS 时，浓度低至 0.001 mg/L 就会导致 D. carinata 死亡和生殖缺陷。使用彗星试验进行的遗传毒性评估表明，在 1 和 10.0 mg/L 下暴露 96 小时，PFOS 会严重损害生物体的遗传结构。鉴于 PFOS 即使在较低浓度（1μg/L）下也可能对水蚤构成风险，本研究结果对评估水生生态系统中 PFOS 和 PFOA 的风险具有重要意义。
