Radionuclide bioconcentration factors and sediment partition coefficients in Arctic Seas subject to contamination from dumped nuclear wastes

The disposal of large quantities of radioactive wastes in Arctic Seas by the former Soviet Union has prompted interest in the behavior of long-lived radionuclides in polar waters. Previous studies on the interactions of radionuclides prominent in radioactive wastes have focused on temperate waters; the extent to which the bioconcentration factors and sediment partitioning from these earlier studies could be applied to risk assessment analyses involving high latitude systems is unknown. Here we present concentrations in seawater and calculated in situ bioconcentration factors for ⁹⁰Sr, ¹³⁷Cs, and ²³⁹+²⁴⁰Pu (the three most important radionuclides in Arctic risk assessment models) in macroalgae, crustaceans, bivalve molluscs, sea birds, and marine mammals as well as sediment K(d) values for 13 radionuclides and other elements in samples taken from the Kara and Barents Seas. Our data analysis shows that, typically, values for polar and temperate waters are comparable, but exceptions include 10-fold higher concentration factors for ^239+240Pu in Arctic brown macroalgae, 10- fold lower K(d) values for ⁹⁰Sr in Kara Sea sediment than in 'typical' temperate coastal sediment, and 100-fold greater Ru K(d) values in Kara Sea sediment. For most elements application of temperate water bioconcentration factors and K(d) values to Arctic marine systems appears to be valid.