Metallic trace elements in wild and farmed fish from the Aveiro Region (Portugal)

This study assessed the concentrations of 11 metallic trace elements (MTEs: As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Se, Zn) in fish muscle from eight wild and farmed species collected in the Aveiro region of Portugal, an area historically affected by industrial pollution. A total of 66 samples were analyzed by ICP-MS. Mean concentrations (mg/kg ww), arranged in ascending order, were: Ni (0.0001), Cd (0.0015), Co (0.0020), Pb (0.0023), Cr (0.0179), Mn (0.0862), Cu (0.2500), Se (0.2964), Fe (1.9236), As (1.9260, total As), and Zn (3.3701). Significant differences were observed among species and between wild and farmed fish, particularly in Dicentrarchus labrax and Sparus aurata. Although Cd and Pb concentrations remained below current European maximum levels, risk assessment based on safe consumption limits (SCLnc) identified total Se, Cd, and Pb as the most restrictive elements for daily intake, especially in children. For arsenic, only total concentrations were considered, as inorganic As could not be distinguished in this study. No significant non-carcinogenic risks were identified at current national average fish consumption levels; however, the potential cumulative and synergistic effects of multiple metals in chronic exposure warrant further investigation. The Metal Pollution Index (MPI < 1 for all samples) confirmed low overall contamination. These findings underscore the importance of ongoing monitoring of trace elements in fish to ensure food safety and protect vulnerable populations.