ZEBRA MUSSELS (DREISSENA-POLYMORPHA) AS A BIOMONITORING TOOL FOR SR-90 CONTAMINATION

Due to their efficient filtration capabilities, zebra mussels (Dreisse na polymorpha) are effective bio-monitors of a wide range of environme ntal pollutants. In this study we test the suitability of zebra mussel s as bio-monitors of Sr-90 contamination around a nuclear power statio n situated at Gentilly, Quebec along the St. Lawrence River. Based on the latest emission data which indicated negligible contributions of S r-90 to the river, we hypothesize that dreissenids collected at sites upstream (Montreal), at the station and downstream from the station (D onnacona) would show no significant differences in shell concentration s of Sr-90. Zebra mussel shell concentrations of Sr-90 were in the ord er of 0.02 pCi/g at Gentilly, 0.04 pCi/g at Montreal and 0.03 pCi/g at Donnacona, all values being below the limit of detection of the analy tical method. We also considered the implication of Sr-90 contaminatio n to higher trophic levels in the food chain.