Abstract
Selective determination of inorganic arsenic (III), (V) and organic arsenic by the solvent extraction method was done with 20 species of marine organisms, including fish, ascidian, holo-thurian, sea urchin, crustacean, shellfish, cephalopod, polychaete, and seweed. In all species, inorganic arsenic, which is more highly toxic than organic arsenic, comprised only a small part (0-7%) of the total arsenic; the one exception was in a seaweed Hizikia fusiforme, in which inorganic arsenic accounted for 60% of the total arsenic. Furthermore, when arsenic in water-soluble and fat-soluble fractions was determined, the ratio of water-soluble arsenic reached 58-97% of the total arsenic. Especially in the cephalopod (3 species) and fish (6 species), more than 84% of the total arsenic was found in the water-soluble fraction. These results strongly suggested that most arsenicals in marine organisms are present in water-soluble organic forms.
