Cytotoxic and genotoxic effects of perfluorododecanoic acid (PFDoA) in Japanese medaka

Abstract

This study investigated the cytotoxic and genotoxic potential of perfluorododecanoic acid (PFDoA), a perfluorinated carboxylic chemical (PFC) that has broad applications and distribution in the environment in Japanese medaka, Oryzias latipes. Micronucleus (MN) test and Comet assay were used for the toxicity study. Three groups of fish were exposed to 0.1 mg/L, 0.5 mg/L and 2.5 mg/L concentration of the chemical for 28 days. Another group served as control. Sampling of the fish blood and liver were done after days 1, 4, 7, 14, 21 and 28 for analysis of different erythrocyte abnormalities and damage to DNA using the MN test and Comet assay respectively. Results showed that there was a significant time and concentration dependent increase (p < 0.05) in percent tail length of DNA and frequency of erythrocyte abnormalities. Nuclear abnormalities observed include micronucleus, fragmented apoptotic cells, lobed nuclei, and bean-shaped cells. Increase in induction of erythrocyte abnormalities and percent tail length of DNA peaked at days 14 and 7, respectively, after which there was a gradual decline. The results indicate that sub-chronic exposure of PFDoA to Japanese medaka caused DNA damage with a simultaneous induction of different erythrocyte abnormalities.