Studies on behavior of long-lived actinides plutonium and americium in the Baltic Sea; effect of season, distribution coefficients in particulate matter and surface sediment

Concentrations found are similar to other seas at the same latitude and probably originate from fallout. Both elements increased in concentration in surface waters in summer. Americium was more closely associated with particulate matter than Pu. Analysis of particulates showed similar concentrations to those in surface layers of sediments. Ksub(d) values for both were 105-106, very similar to results reported elsewhere. In contrast to deep sea regions, 2% of Pu and Am were in the water column and 98% in the sediments. A method for separating Pusup(III,IV) and Pusup(V,VI) in water was developed which relies on NdF3 coprecipitation. (author)