Arsenic speciation and bioaccessibility in raw and cooked seafood: Influence of seafood species and gut microbiota.

Abstract Seafood is an important source of arsenic (As) exposure for humans. In this study, 34 seafood samples (fishes, shellfishes, and seaweeds) collected from different markets in China were analysed for total and speciated As before and after boiling. Furthermore, the As bioaccessibility was also assessed using a physiologically based extraction test combined with the Simulator of Human Intestinal Microbial Ecosystems. The results showed that the total As (tAs) contents of seaweeds (raw: 44.12; boiled: 31.13, μg·g−1 dw) were higher than those of shellfishes (raw: 8.34; boiled: 5.14, μg·g−1 dw) and fishes (raw: 6.01; boiled: 3.25, μg·g−1 dw). Boiling significantly decreased the As content by 22.24% for seaweeds, 32.27% for shellfishes, and 41.42% in fishes, respectively (p   0.05). With the effect of gut microbiota, arsenate (AsⅤ) was transformed into monomethylarsonic acid (MMA) and arsenite (AsⅢ) in C. Moreover, as for seaweeds, an unknown As compound was produced.