Effects of acute and chronic exposure to perfluorodecanoic acid (PFDA) and perfluorotridecanoic acid (PFTrDA) in Daphnia magna and Zebrafish (Danio rerio) with endocrine disruption potential

Abstract

Perfluorolalkyl acids (PFAAs) have been frequently detected in both the environment and biota, however the endocrine disruption potentials and underlying mechanism of long-chain PFAAs have not yet been fully understood. In the present study, the effects of perfluorodecanoic acid (PFDA) and perfluorotridecanoic acid (PFTrDA) on Daphnia magna and sex steroid hormones and expression of mRNA of selected genes in hypothalamus-pituitary-gonad (HPG) axis were evaluated after 120 d exposure of zebrafish. PFDA and PFTrDA affected growth and delayed the time required for reproduction of the first brood of D. magna, respectively. CYP19A and VTG1 genes were up-regulated in male fish by exposure to PFDA and PFTrDA. In male zebrafish, concentrations of 11-ketotestosterone (11-KT) and T were significantly decreased at 0.1 mg/L PFTrDA. Significantly increased ratios of 17β-estradiol (E2)/T and E2/11-KT were observed in male zebrafish after exposure to PFDA and PFTrDA, indicating balance of sex hormones were disrupted, which could further result in adverse effects on reproduction in fish. The results of this study showed that long term exposure to PFDA and PFTrDA could affect sex steroid hormones and related gene transcriptions.