Mercury and selenium accumulation assessment in fish most consumed by Cubatao Community, Sao Paulo, Brazil

High correlation between mercury (Hg) and selenium (Se) concentrations in fish organs is well known. In the present study, 58 fish samples of five fish species most commonly consumed by the Cubatao city population, Sao Paulo State, Brazil were analyzed. The Cubatao Estuary, located in southeastern Sao Paulo State, is an economically important area suffering severe environmental water quality problems due to industrial wastes, domestic sewage and solid residues. The waters of the bay suffer the impact of the immense industrial complex of Cubatao. In this study, Hg concentration in muscle, liver and kidney tissues and Se concentration in liver tissue from three predatory fish species: Macrodon ancylodon (Pescada), Menticirrhus americanus (Perna de Moca) and Micropogonias furnieri (Corvina) and two planctivorous species: Mugil liza (Tainha) and Sardella braziliensis (Sardinha) were determined. Mercury determination was performed using Cold Vapour Atomic Absorption Spectrometry (CV AAS) and selenium by Instrumental Neutron Activation Analysis (INAA). The muscle-Hg concentration variation (wet weight) was: (8 to 40 μg kg-1) - Sardinha; (12 to 62 μg kg-1) - Pescada; (3 to 23 μg kg-1) - Tainha; (43 to 184 μg kg-1) - Perna de Moca and (41 to 348 μg kg-1) - Corvina. The general concentration ranges of the analyzed elements in all species studied were (dry weight): muscle-Hg (13 to 1512 μg kg-1); liver-Hg (21 to 1804 μg kg-1); kidney-Hg 47 to 9912 μg kg-1) and liver-Se (2.10 to 43.00 mg kg-1). Se concentrations were higher than those of Hg in the liver. (author)