Study of the distribution of metals in tissues of fish from amazon region

Abstract

The purpose of this study was to evaluate the levels of Al, Ca, Cu, Fe, Mg, Mn, Na, Pb and Zn in 15 samples of five fish species (Brachyplatystoma rousseauxii, Brachyplatystoma filamentosum, Cynoscion leiarchus, Brachyplatystoma vaillanti e Colossoma macropomum) obtained in municipal market of Belém (Pará State, Brazil). These samples were digested in a cavity microwave oven using a 3.5 mol L-1 nitric acid solution and concentrated hydrogen peroxide. Total concentrations of the studied elements were determined by flame atomic absorption spectrometry (FAAS) and graphite furnace atomic absorption spectrometry (GF AAS). The contents of the elements in fish samples ranged from 90.12-2497.09 μg g-1 for Al, 114.05-7100.10 μg g-1 for Ca, 43.2-150.1 μg g-1 for Cu, 22.26-4296.62 μg g-1 for Fe, 514.03-7520.13 μg g-1 for Mg, 20.05-20.08 μg g-1 for Mn, 227.93-7315.56 μg g-1 for Na, 0.54-11.81 μg g-1 for Pb, and 7.46-129.74 μg g-1 for Zn. Results show that higher levels of the elements studied were found in the liver and lower levels in the muscle of fish. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were applied to check correlations between mineral composition, length and mass of fish samples studied.