Nutritional Quality and Assessment of Contaminants in Farmed Atlantic Salmon (Salmo salar L.) of Different Origins

Abstract

Atlantic salmon represents an important source of valuable proteins and lipids rich in n-3 fatty acids and micronutrients. However, there are reports that these marine fish still contain contaminants at levels that raise health concerns. Although the Stockholm Convention already bans some compounds, they can still be detected because of their persistence. The present study reports nutritional parameters and the occurrence of persistent and bioaccumulative chemicals in the tissues of fifty-five salmon from several major farming areas. The protein content of all samples was almost identical, averaging to 19.2% w/w, while lipids averaged 14.9% w/w. Fish from Chilean farms contained 6.0% less fat and a lower level of vitamin E than from other sources, that is, 2.2 mg per 100 g (w/w). Fish from Scottish farms contained higher levels of eicosapentaenoic and docosahexaenoic acid. Halogenated contaminants from polychlorinated biphenyls, organochlorinated pesticides, brominated flame retardants, and perfluoroalkylated and polyfluoroalkylated substances were measured, and generally, they were found to be at very low concentrations that did not exceed the legislation limits applicable in the European Union. These results showed that the compositional differences between Atlantic salmon from several important farming areas were only minor, but some significant differences were demonstrated in total fat content and fatty acid profiles.