Mercury, selenium and cadmium in juvenile blue (Prionace glauca) and smooth hammerhead (Sphyrna zygaena) sharks from the Northwest Mexican Pacific coast.

Cadmium, selenium, and mercury concentrations were measured in muscle and liver of juvenile blue (Prionace glauca) and smooth hammerhead (Sphyrna zygaena) sharks caught on the west coast of Baja California Sur, Mexico, to evaluate the human health risk associated with its consumption. Cd and Hg were lower than the maximum allowable limit for human consumption established by the Mexican government (Hg = 1.0 μg g^-1 and Cd = 0.50 μg g^-1). Interspecific differences in trace elements accumulation denoted diet variations and physiological requirements of each shark species. Calculated biomagnification factor (BMF) values confirmed a prey-predator trophic transfer of elements. Not significant results of Selenium health benefit Index value (P. glauca = −0.46; S. zygaena = −0.02) signify no potential risks for human health. However, calculated Hazard Index values displayed possible health hazards to the children who consume blue shark meat regularly. The local population is advised regarding the ingestion rates of shark. [Display omitted] • P. glauca and S. zygaena sharks show similar distribution patterns of Cd, Se and Hg. • Hg and Se presented BMF values >1, indicating trophic accumulation process. • High HI values in children, demand regulatory measures in consumption of shark meat. [ABSTRACT FROM AUTHOR]