THE BIOTRANSFORMATION OF MONOMETHYLARSONATE AND DIMETHYLARSINATE INTOARSENOBETAINE IN SEAWATER AND MUSSELS

Water-soluble H-3-labeled arsenic compounds were phenol-extracted from mussels (Mytilus edulis) and seawater after exposure to [H-3]monometh ylarsonate (MMAA) and [H-3]dimethylarsinate (DMAA). Varying amounts of [H-3] arsenobetaine were found in mussels and seawater, depending upo n the experimental conditions. The results indicate that arsenobetaine is principally biosynthesized by microscopic organisms in the seawate r and that it is bioaccumulated by mussels. Total arsenic concentratio ns in mussel flesh, byssal threads and shells were also determined, sh owing concentration increases in all three compartments.