Uptake of Americium and Plutonium from Contaminated Sediments by Three Benthic Species: Arenicola marina, Corophium volutator and Scrobicularia plana
Marine Ecology Progress Series
The biological availability of americium (241Am) and plutonium ( 2 3 8 P~) contained in a muddy sediment was investigated in 3 burrowing coastal benthic species: the polychaete annelid Arenicola marina (L.), the bivalve mollusc Scroblcularia plana (da Costa) and the amphipod crustacean Corophium volutator (Pallas). The biological availability was expressed in terms of a transfer factor defined as the activity in the organisms (cpm g-' wet weight) relative to the activity in the sediment (cpm
... he sediment (cpm g-I wet weight). For the 3 species and both radionuclides, the transfer factors observed were low (< 1) after 14 d in contact with the contaminated sediment. Uptake by C. volutator (TF = 0.1) was 10 times (TF = 0.01) and 50 times (TF = 0.002) greater than uptake by S. plana and A. marina respectively. A comparative investigation of the biological availability of americium and plutonium contained in seawater showed, for the same exposure period, that the concentration in the organism relative to the concentration in the water (C.F.) was about 1000 for americium and 780 for plutonium in C. volutator, but much lower for the other 2 species. The data obtained demonstrate that part of the americium transferred to the organisms comes from the sediment's interstitial water. Part of the americium retained by the animals could therefore result from direct transfer from sedimentary particles to organisms.