Biokinetic behavior of technetium in the red abalone, Haliotis rufescens: a re-assessment

The biokinetic behavior of 95mTc in the red abalone, Haliotis rufescens, is reviewed in light of recent experiments with other molluscs. Additional experimentation has confirmed that, when uptake is directly from labeled seawater, abalones exhibit concentration factors in excess of 100. Bivalve molluscs under the same experimental conditions have concentration factors that do not exceed 2. However, uptake and loss kinetics in the abalone cannot be described by a single compartment model as had been previously advanced. Assimilation of 95mTc by abalones following a single feeding of labeled macroalga, Nereocystis luetkeana, is approximately 45% and loss kinetics are similar to those observed following direct uptake from seawater.