RESUMEN
We determined levels of mercury, cadmium, lead and selenium in muscle and liver of 29 specimens of a large pelagic fish rarely investigated, the Mediterranean spearfish Tetrapturus belone (Raf., 1810). The following element concentration ranking (mean ± S.D.; espressed in mg/kg dry weight) was recorded in muscle: Hg (3.401 ± 1.908) > Se (1.727 ± 0.232) > Pb (0.532 ± 0.322) > Cd (0.019 ± 0.015), and Se (6.577 ± 1.789) > Cd (5.815 ± 3.038) > Hg (2.698 ± 2.214) > Pb (0.661 ± 1.334) in liver. Levels of Hg, Se and Cd were compared to those reported for other Istiophoridae from oceanic areas and for other large predators of Mediterranean Sea, like swordfish and tuna. Organotropism of trace elements and their relation to size was discussed. Ecophysiological considerations regarding the Se-Hg relationship as well as Se-Cd indicate a possible detoxification mechanism. The implications for human consumption are briefly discussed.
Asunto(s)
Monitoreo del Ambiente , Peces , Oligoelementos , Contaminantes Químicos del Agua , Animales , Humanos , Hígado , Mar Mediterráneo , Mercurio , SelenioRESUMEN
The Greenland shark Somniosus microcephalus is an opportunistic feeder, a top predator, and a very long-lived species. The brain, liver, red and white muscle, gonads, fat, skin, pancreas, and spleen of Greenland sharks from NE Greenland fjords were analysed for PCBs, PCDDs/DFs, PBDEs; DDT isomers; HCH isomers; dieldrin; endrin; HCB; Cd, Hg, Pb, and Se. PCBs (2.01-103 ng/g wet wt) and PBDEs (7.9-3050 pg/g wet wt) were detected in most of the samples. PCDDs/DFs showed high values when detected. DDTs, HCB and HCHs were only detected in some tissues. The ΣTEQ was 5.76 pg/g in muscle. Cadmium mainly accumulated in the pancreas and liver (19.6 and 10.7 mg/kg dry wt, respectively); mercury in red muscle (4.10-6.91 mg/kg dry wt); selenium in the pancreas (3.57 mg/kg dry wt) and spleen (1.95 mg/kg dry wt); lead in the skin (0.358 mg/kgd ry wt). The selenium-mercury ratio in the liver was also evaluated.