DNA Double-Strand Breaks in Arctic Char (Salvelinus alpinus) from Bjornoya in the Norwegian Arctic

High levels of organochlorine contaminants (OCs) have been found in arctic char (Salvelinus alpinus) from Lake Ellasjoen, Bjornoya (Norwegian Arctic). The aim of the present study was to investigate the potential genotoxic effect of environmental organochlorine contaminant exposure in arctic char from Ellasjoen compared with arctic char from the low-contaminated Lake Laksvatn nearby. Blood was analyzed using agarose gel electrophoresis and image data analysis to quantify the fraction of total DNA that migrated into the gel (DNA-FTM) as a relative measure of DNA double-strand breaks (DSBs). Analysis by GC-MS of muscle samples showed an average 43 times higher concentration of sigma OCs in arctic char from Ellasjoen (n = 18) compared with Laksvatn char (n = 21). Char from Lake Ellasjoen had a much higher frequency of DSBs, as measured by DNA-FTM, than char from Lake Laksvatn. Principal component analysis and multiple linear regressions show that there was a significant positive relationship between DSBs and levels of organochlorine contaminants in the char. In addition, DSBs were less frequent in reproductively mature char than in immature char. The results suggest that organochlorine contaminants are genotoxic to arctic char. Environ Toxicol Chem 2019;00:1-9. (c) 2019 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.