USE OF AN ULTRAFILTRATION AND GAMMA-RAY IRRADIATION TECHNIQUE FOR STUDYING THE SPECIATION OF TRACE-ELEMENTS IN RIVER WATERS

The physicochemical forms of 38 elements in several river waters were measured by size fractionation combined with a gamma (gamma)-ray irrad iation technique and a neutron activation analysis. The gamma-ray irra diation technique was effectively utilized to decompose organic materi als in the river waters and made it possible to estimate the physicoch emical forms of trace elements. The dissolved species for alkali and a lkaline earth elements, Al, V, Mn, Sb and Au were present mainly as si mple inorganic ions in the river waters. The dissolved species of Sc, Cr, Co, Ni, Zn, Se, Ho, Tm, Yb, and Lu predominantly existed as solubl e organic complexes, even though significant amounts of Cr, Co, Ni, Zn , and Se were also present as simple ions. The dissolved species of Fe , Ag, La, Ce, Sm, and Eu, on the other hand, were chiefly associated w ith organic colloids.