Aluminium content in edible parts of seafood

Abstract

 Samples of the edible parts of different fish species and of crustacean and molluscan shellfish were collected in the North Sea, the Barents Sea, the Baltic Sea, the Northeast Atlantic, and in Greenland waters. Most of the aluminium concentrations in fillets of lean and fatty fish were lower than 0.2 mg Al/kg wet weight. Exceptions were the aluminium concentrations in fillets of fish caught near an aluminium smelting plant (up to 1 mg Al/kg wet weight). Presumably a connection between the aluminium content in sea water and the fish fillets is responsible for this. The investigations of fillets of saithe, haddock, and cod with different lengths (age) showed that the aluminium levels decreased with increasing length, however, the decrease was not significant. An aluminium accumulation in muscle tissue with increasing age could not be detected. A comparison between fillets and different organs of cod showed higher aluminium concentrations in organs, especially in gills. The aluminium intake via gills, which are in continuous contact with the ambient water, is responsible for this. In the edible part of crustacean and molluscan shellfish higher aluminium concentrations (up to 5 mg Al/kg wet weight) were detected. The different feed spectrum and metabolism of these species seem to be responsible for the higher aluminium accumulation in marine crustacean and molluscan shellfish.