Transfer of polonium-210 into Mytilus edulis (L.) and Fucus vesiculosus (L.) from the baie de Seine (Channel coast of France)

During the period from March 1990 to November 1991, the distribution of 210Po activity in Fucus vesiculosus and Mytilus edulis was studied in the Seine estuary as well as at some other stations outside the estuary. The estuarine zone of the Seine is the site of industrial releases of phosphatic gypsum waste. In Mytilus edulis, activities range from 90 to 700 Bq kg−1 dry wt., whereas Fucus vesiculosus yields values of 3–22 Bq kg−1 dry wt. The distribution of 210Po activity indicates the existence of significant geographical zonation in both of these species, as well as some seasonal fluctuations involving the mussels at certain stations. The factors influencing these distributions are discussed, including the ecological and physicochemical parameters of the system.