Content of selected elements in the muscle tissue of plaice (Pleuronectes platessa) and garfish (Belone belone) from the Baltic Sea

Fish are an important component of a balanced human diet. Marine fish are more popular than freshwater fish among Polish consumers. All fish are an excellent source of minerals, which the human body cannot synthesize. Hence, they should be provided with food in right amounts and proportions. However, fish can be contaminated by heavy metals. For this reason, it is very important to determine the levels of selected trace elements in fish. The aim of this study was to compare the content of mineral compounds in the muscle tissue of two species of fish from the Baltic Sea, i.e. plaice (Pleuronectes platessa) and garfish (Belone belone). Wet-digested fish muscle samples were used to analyze the content of macro- (K, Na, Ca, Mg), and micronutrients (Zn, Fe, Mn, Cu) determined with flame atomic absorption spectrometry (AAS), and the levels of heavy metals (Cd, Pb) using flameless AAS. No significant differences between the species in the concentrations of K, Mg, Ca, Cu and heavy metals appeared, while the Na, Mn, Zn and Fe concentrations were significantly different between the two fish. Higher levels of Na, Mg, Mn and heavy metals were determined in muscle tissue of European plaice, while concentrations of the other macroand micronutrients were higher in muscles of garfish. The muscles of both species showed equal levels of Cd and Pb, below the maximum allowable limits.