METAL ACCUMULATION IN FRESHWATER MOLLUSKS OF CENTRAL PENNSYLVANIA

Bioaccumulation of heavy metals in freshwater mollusks has been used to provide information concerning concentrations of heavy metals in streams to measure water quality. The study aims to use geochemical analysis methods to find potential sources of metal origins. The different species of freshwater mollusks collected during this study have shown different heavy metal accumulation sensitivities, providing a more dynamic understanding of low-level and intermittent sources of metal pollution. This study was conducted by collecting water samples, Asian clams (Corbicula fluminea) and River Snails (Pleurocera sp. a Campeloma sp.) along the Juniata River locality and comparing them to the metal accumulation concentrations to freshwater mollusks collected from the Susquehanna River in Central Pennsylvania. The addition of Campeloma sp. collected from the Susquehanna River provided a more complex insight to metal accumulation across species. Analysis of 14 different elements were conducted with particular interest in cadmium, copper, lead, aluminum, iron, strontium, and mercury for ion concentrations. Collection sites were intentionally selected for their different hydrogeologic conditions, including differences in stream discharge rates, geologic formation, and lithology. All snails showed higher levels of metal accumulation compared to clams taken from the same site collection location consistently. While the snails’ metal accumulations were higher compared to clams, the elements that appeared in higher concentrations in the snails differed by collection site location. Highest metal content existed in snails and clams from Sinking Valley which can be attributed to weathering of sulfide minerals.