Stage- and tissue-specific cadmium accumulation in Portunus trituberculatus during gonadal maturation

Cadmium (Cd) accumulation in Portunus trituberculatus raises food safety concerns, yet its tissue-specific distribution during gonadal maturation remains poorly understood. Previous studies commonly combined hepatopancreas and gonads as “brown meat”, making it difficult to determine the relative contribution of individual tissues to Cd accumulation. Therefore, we systematically investigated Cd distribution across six ovarian developmental stages using precise anatomical dissection and ICP-MS analysis. Results showed that the hepatopancreas was the predominant Cd accumulation tissue, accounting for ≥97% of total Cd in edible tissues (11.3–42.9 mg/kg wet weight). In contrast, Cd concentrations in ovaries remained low (0.162 mg/kg), and Cd levels in eggs were near the detection limit (0.070 mg/kg), indicating that gonads are not the primary Cd accumulation site. The hepatosomatic index (HSI) declined significantly during vitellogenesis, while ovarian Cd concentrations exhibited stage-specific variations during maturation. These findings clarify tissue-specific Cd partitioning in Portunus trituberculatus and provide new insights into Cd distribution and potential detoxification processes in crustaceans. The results also offer valuable information for tissue-specific food safety assessment of this economically important species.