Reproductive cycle influences trace metal(loid) distribution in the spottail mantis shrimp Squilla mantis from the Adriatic Sea.

This study investigated the accumulation of 13 metal(oid) s (Ag, Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn) in muscle and gonadal edible tissues of Squilla mantis from the central Adriatic Sea, considering pre-spawning, spawning, and post-spawning reproductive phases. A total of 69 specimens were analyzed. Compliance with EU limits was observed for Hg, Cd and Pb. Total As concentrations were higher, though regulatory thresholds apply specifically to inorganic As. Concentrations of essential metals varied significantly among tissues and reproductive phases, with gonads accumulating higher levels than muscle, particularly post-spawning. Multivariate analysis revealed clear patterns of metal co-accumulation, with post-spawning gonads showing the highest levels and driving most of the separation among tissue and reproductive phase groups. Kruskal-Wallis tests confirmed significant tissue- and phase-specific differences. The calculated Hazard Quotient (HQ) and cumulative Hazard Index (HI) values remained below unity, suggesting negligible non-carcinogenic health risks associated with the consumption of S. mantis. These findings provide a comprehensive multielement baseline for S. mantis, supporting risk assessment and informed management of this commercially relevant species.