Am-241Pu-239 + 240 ratios in the marine environment

The $\text{Am}\text{-241}\text{Pu}\text{-239 + 240}$ ratio is at least a factor of two higher in the particulate phases of California coastal waters than the values previously reported for unfiltered waters and sediments. These results are attributed to a greater water solubility for plutonium relative to americium species. The values of the ratio in mussels indicate primarily a particulate uptake of these transuranics. Sorption experiments of these two elements from seawater to glass beads, rayon fibres and filter papers are consistent with an uptake of the particulate phases.