Furthermore, our unpublished data indicated that the bivalves were not able to selectively ingest particles from a particle mixture (e.g. diatom and sediment) at this low particle concentration (Ke and Wang, in preparation). After feeding on radiolabeled sediment for 30 min (or 10 min in the oxic / anoxic experiment described below), the
bivalves were rinsed and their radioactivity was measured non-destructively with a gamma counter.