Which part of an edible clam poses the highest health concern? A tissue-specific assessment of PAH bioaccumulation in Ruditapes philippinarum

The growing global emphasis on food safety, coupled with projected increases in seafood consumption, underscores the need for rigorous health risk assessments associated with dietary intake of seafood products. This study investigates the distribution and ecological risk of PAHs in seawater and sediment, and further examines tissue-specific patterns of PAHs bioaccumulation in the clam Ruditapes philippinarum from typical bays of the Bohai Sea and the Yellow Sea. PAHs concentrations in environmental media were within globally reported ranges, with elevated ecological risks observed in a semi-enclosed, urban-adjacent bay (Jiaozhou Bay). Among tissues, the digestive gland consistently showed higher PAH accumulation and bioaccumulation factors than other organs. Health risk assessment approaches (ILCR and MOE) indicated generally acceptable risks from whole soft tissue consumption, while tissue-level scenarios identified the digestive gland as a dominant contributor to potential exposure. These findings provide mechanistic insight into tissue-specific PAHs accumulation and support targeted risk-reduction strategies in seafood consumption.