NEUTRON ACTIVATION ANALYSIS OF MERCURY, COPPER AND ARSENIC IN MARINE ORGANISMS

The mercury, copper, and arsenic contents of some marine organisms were determined by neutron activation. The irradiations were carried out in JRR-1 reactor, with neutron fluxes of about 3 x 10/sup 11/ n/cm/sup 2//sec, and the irradiation lasted 2 to 3 days (intermittently, 5 hr each day). After cooling for 2 days the sample was dissolved by treating with nitric-sulfuric acid and potassium permanganate in the presence of carriers. From the clear solution the mixed sulfides were separated from the bulk of the contaminating activities, and the arsenic and copper was dissolved by treating successively with hot 6 N ammonium polysulfide and 6 N nitric acid, leaving the mercury sulfide unattacked. Further decontamination chemistry was carried out for each element. The amount of the element in the marine organisms was then determined by comparing Hg/sup 203/, Cu/sup 64/, and As/sup 76/ ore resistant t activities isolated from the sample with those from the monitor. The mean chemical yield was 40, 65, and 30% for mercury, copper, and arsenic, respectively, and the sensitivity of the method was Hg 1.5 ation g, Cu 0.03 ation g, and As more » 0.04 ation g. The method makes it possible to minimize loss and contamination, the greatest obstacles in other analytical techniques for the determination of extremely minute amounts of these elements. (auth) « less