Potentially toxic elements in commonly consumed fish species from the western Mediterranean Sea (Almería Bay): Bioaccumulation in liver and muscle tissues in relation to biometric parameters.

Marine pollution is one of today's most relevant problems. Public awareness has been raised about the harmful potential of heavy metals (HMs) accumulating in edible fish and possibly ending up in human diet through the food chain. This study aimed to characterize and evaluate As, Cd, Cr, Cu, Ni and Pb contents in four edible fish species from the western Mediterranean Sea. Liver and muscle toxic elements were determined by GF-AAS in Mullus surmuletus, Merluccius merluccius, Auxis rochei and Scomber japonicus from Almería Bay (Spain). Muscular composition, biometrics and trophic levels were also determined. The mean PTE concentration levels (mg kg-1, DW) in fish muscle tissue were: As (2.90-53.74), Cd (0.01-0.18), Cr (0.53-2.01), Cu (0.78-6.93), Ni (0.06-0.24), Pb (0.0-0.32). These concentrations did not exceed the maximum limits set by European legislation (Commission Regulation (EC) No. 1881/2006) for the intake of these marine species. Accumulation of toxic elements tends to be seen in the liver (As (7.31-26.77), Cd (0.11-8.59), Cr (0.21-2.94), Cu (2.64-16.90), Ni (0.16-1.03), Pb (0.0-0.99)). As was the element at highest risk in this Mediterranean region, especially due to red mullet values in muscle. The high As contents with living habits as benthic species that feed near the coast. HMs, especially muscle Cd contents, were associated with higher contents of lipids and organic matter, and bigger specimen size (length and weight), while As was linked to higher fish protein content. However, these relationships between potentially toxic elements (PTE) and biometric indices and body composition parameters depend on species. Finally, the THQ indices indicated that eating fish from Almería Bay poses no human health risk despite pollution from the Almería coastline.

Mercury contents in relation to biometrics and proximal composition and nutritional levels of fish eaten from the Western Mediterranean Sea (Almería bay).

Total liver and muscle mercury, and muscular composition, biometrics and trophic levels, were determined in four species (Mullus surmuletus, Merluccius merluccius, Auxis rochei and Scomber japonicus) of the Mediterranean Sea (Almería Bay, Spain). Mercury levels did not exceed the maximum residue limit, and M. merluccius obtained the highest level in muscle. Considerable variations in Hg content among individuals were observed in non-gregarious species. A positive correlation between Hg and trophic level or length was found in muscle, but not in liver. Organs (liver or muscle) with major Hg accumulation depend on species; muscle in M. merluccius and liver in S. japonicus. The results indicate that Hg levels in fish depend on intra- and interspecies factors that should be taken into account in systems to monitor Hg levels.