Partition of radiotracers between suspended particles and seawater

Distinctive uptake mechanisms of different radiotracers by red clays in seawater are elucidated from the magnitude and change of distribution coefficients (Kd) for up to 17 γ-emitting radiotracers as functions of equilibration time, suspended particle concentration and compositions of solids and seawaters. The adsorption of ionic metals onto colloids and subsequent coagulation of colloids onto larger particles are the dominant removal processes of metals in the aquatic environments of low suspended particle concentration.