First report of the mercury, cadmium and lead concentrations in the tissues of wild amberjacks (Seriola spp.) caught in Gran Canary (Canary Islands, Spain)

Abstract

Amberjack (Seriola spp.) is a commercially valuable fish species in the Canary Islands, yet data on toxic heavy metals in its tissues remain scarce. This study presents the first assessment of mercury (Hg), cadmium (Cd), and lead (Pb) concentrations in muscle, liver, and gonads of wild specimens caught in Gran Canaria and confiscated due to ciguatoxin presence. Hg levels in muscle tissue were notably high, with 73 % of specimens exceeding the European legal limit (median: 0.80 mg/kg). Cd and Pb levels in muscle remained below detection thresholds. Liver tissues showed substantial accumulation of Hg (median: 1.72 mg/kg) and Cd (median: 3.00 mg/kg), with 100 % of specimens surpassing the Cd legal limit. Gonadal tissues exhibited lower concentrations, with a significant negative correlation between Cd levels and gonad weight, suggesting possible elimination during spawning. Despite elevated Hg concentrations in muscle, the human health risk assessment—based on Estimated Daily Intake (EDI) and Target Hazard Quotient (THQ)—indicated values below critical thresholds for both adults and children, suggesting no immediate health risk under current consumption patterns. These findings highlight the liver as a key organ for heavy metal bioaccumulation and underscore the limitations of current food safety regulations, which focus solely on muscle tissue. Expanding monitoring protocols to include liver and gonads is recommended to better reflect toxicological risks and safeguard public health in regions where Seriola spp. is regularly consumed.