Distribution of inorganic arsenic and methylated arsenic in marine organisms

Inorganic arsenic and methylated arsenic compounds in 60 specimens of marine organisms were investigated by hydride generation derivatization and cold‐trap gas chromatography–mass spectrometry (GC MS). Chloroform–methanol extracts from seaweeds, shellfish, fish, crustaceans and other marine organisms were separated into water‐soluble and lipid‐soluble fractions. The arsenic compounds in each fraction were identified and analysed as arsine, methylarsine, dimethylarsine and trimethylarsine. Trimethylarsenic compounds were distributed mainly in the water‐soluble fraction of muscle of carnivorous gastropods, crustaceans and fish. The amounts of dimethylated arsenic compounds were found to be larger than that of trimethylated arsenic in the lipid‐soluble fraction of fish viscera. Dimethylated arsenic compounds were distributed in the water‐soluble fraction of Phaeophyceae.