OCCURRENCE AND BIOACCUMULATION OF PFAS IN BIVALVE MOLLUSKS: A SYSTEMATIC REVIEW

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants that have been widely detected in aquatic ecosystems and seafood. Due to their filter-feeding behavior and bioaccumulation capacity, bivalve mollusks are considered important bioindicators of environmental contamination. This systematic review aimed to evaluate the occurrence and distribution of PFAS in bivalve mollusks and identify recent trends in contamination profiles. A systematic literature search was conducted in the Scopus and ScienceDirect databases, including original articles published between 2019 and 2025. After screening and eligibility assessment, 34 studies were included in the review. Most studies were conducted in North America, Europe, and China, revealing a significant geographic bias and limited information from developing regions. Legacy PFAS compounds, especially perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), were the most frequently reported contaminants, while an increasing number of recent investigations reported emerging compounds such as including trifluoroacetic acid (TFA), FHxSA, PFBS and C6O4. PFOA concentrations ranged from 0.185 to 111.57 ng/g wet weight (ww), while PFOS concentrations ranged from 0.002 to 1137 ng/g ww, demonstrating substantial variability among species and locations. The most frequently investigated species were, Mytilus galloprovincialis, Crassostrea virginica, and Ruditapes philippinarum. The findings confirm the widespread occurrence of PFAS in bivalves and highlight concerns regarding environmental persistence and food safety. The increasing detection of replacement compounds emphasizes the need for continued monitoring and further investigation of their ecological and toxicological implications under a One Health perspective.