The content and the oxidation state of arsenic and antimony in coastal water of Japan

The content and the oxidation state of arsenic and antimony in coastal seawater were determined coupled with chemical separation and neutron activation method. The contents of arsenic and antimony in coastal seawater were estimated to be 1.56–2.73g As/l, 0.25–0.57g Sb/l. Most parts of these elements exist as soluble ionic species, passing through 0.45 pore-size membrane filter, and at surface, 80–97% of arsenic occurs as arsenate and 70–94 % of antimony may occurs as antimonate. The vertical distribution of arsenite and arsenate is almost constant from the surface to 1,200 m depth. However the distribution of Sb(III) and Sb(V) is much more complicated with depth.