Bioaccumulation and uptake routes of perfluoroalkyl acids in Daphnia magna

• Published in: Chemosphere (Oxford) Vol. 90; no. 5; pp. 1589 - 1596
• Main Authors: Dai, Zhineng, Xia, Xinghui, Guo, Jia, Jiang, Xiaoman
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.02.2013; Elsevier
• Subjects: Animal, plant and microbial ecology; Animals; Applied ecology; Bioaccumulation; Biological and medical sciences; Daphnia - metabolism; Daphnia magna; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on protozoa and invertebrates; Fluorocarbons - analysis; Fluorocarbons - metabolism; Fundamental and applied biological sciences. Psychology; hydrophobicity; partition coefficients; Perfluorinated compounds (PFCs); PFAs; Scenedesmus; sorption; Uptake route; Water Pollutants, Chemical - analysis; Water Pollutants, Chemical - metabolism; Uptake route; Bioaccumulation; PFAs; Daphnia magna; Perfluorinated compounds (PFCs); Emerging contaminant; Organic perhalocompound; Pollutant behavior; Cladocera; Biological indicator; Uptake; Crustacea; Carboxylic acid; Arthropoda; Kinetics; Fluorine Organic compounds; Invertebrata; Biological accumulation; Branchiopoda
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2012.08.026

► PFAs were considered as one kind of moderate accumulative compounds for Daphnia magna. ► The bioaccumulation factors of PFAs were positively correlated with their logKow. ► Dietary effect was not significant on the bioaccumulation of PFAs by D. magna. ► Body surface sorption dominated the bioaccumulation of PFAs in D. magna. Perfluoroalkyl acids (PFAs), one kind of emerging contaminants, have attracted great attentions in recent years. However, the study about their bioaccumulation mechanism remains scarce. In this research, the bioaccumulation of six kinds of PFAs in water flea Daphnia magna was studied. The uptake rates of PFAs in D. magna ranged from 178 to 1338Lkg−1d−1, and they increased with increasing perfluoroalkyl chain length; the elimination rates ranged from 0.98 to 2.82d−1. The bioaccumulation factors (BAFs) of PFAs ranged from 91 to 380Lkg−1 in wet weight after 25d exposure; they increased with increasing perfluoroalkyl chain length and had a significant positive correlation with the n-octanol/water partition coefficients (logKow) of PFAs (p<0.05). This indicated that the hydrophobicity of PFAs plays an important role in their bioaccumulation. The BAFs almost kept constant when the PFA concentrations in aqueous phase increased from 1 to 10μgL−1. Scenedesmus subspicatus, as the food of D. magna, did not significantly affect the bioaccumulation of PFAs by D. magna. Furthermore, the body burden of PFAs in the dead D. magna was 1.08–2.52 times higher than that in the living ones, inferring that the body surface sorption is a main uptake route of PFAs in D. magna. This study suggested that the bioaccumulation of PFAs in D. magna is mainly controlled by their partition between organisms and water; further research should be conducted to study the intrinsic mechanisms, especially the roles of protein and lipid in organisms.