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Indexed by:期刊论文

Date of Publication:2018-02-01

Journal:ENVIRONMENTAL POLLUTION

Included Journals:SCIE、EI、PubMed

Volume:233

Page Number:8-15

ISSN No.:0269-7491

Key Words:Polyfluorinated compounds; Alga; Bioaccumulation; Membrane property; Oxidative stress

Abstract:Chlorinated polyfluorinated ether sulfonate (CI-PFESA) is a novel alternative compound for perfluorooctane sulfonate (PFOS), with its environmental risk not well known. The bioaccumulation and toxic effects of CI-PFESA in the freshwater alga is crucial for the understanding of its potential hazards to the aquatic environment. Scenedesmus obliquus was exposed to CI-PFESA at ng L-1 to mg L-1, with the exposure regime beginning at the environmentally relevant level. The total log BAF of CI-PFESA in S. obliquus was 4.66, higher than the reported log BAF of PFOS in the freshwater plankton (2.2-3.2). CI-PFESA adsorbed to the cell surface accounted for 33.5-68.3% of the total concentrations. The IC50 of CI-PFESA to algal growth was estimated to be 40.3 mg L-1. Significant changes in algal growth rate and chlorophyll a/b contents were observed at 11.6 mg L-1 and 13.4 mg L-1 of CI-PFESA, respectively. The sample cell membrane permeability, measured by the fluorescein diacetate hydrolyzation, was increased by CI-PFESA at 5.42 mg L-1. The mitochondrial membrane potential, measured by Rh123 staining, was also increased, indicating the hyperpolarization induced by CI-PFESA. The increasing ROS and MDA contents, along with the enhanced SOD, CAT activity, and GSH contents, suggested that CI-PFESA caused oxidative damage in the algal cells. It is less possible that current CI-PFESA pollution in surface water posed obvious toxic effects on the green algae. However, the bioaccumulation of CI-PFESA in algae would contribute to its biomagnification in the aquatic food chain and its effects on membrane property could potentially increase the accessibility and toxicity of other coexisting pollutants. (C) 2017 Elsevier Ltd. All rights reserved.