Trace Metals in Aquatic Invertebrates in Stormwater Retention Ponds in Suburban Maryland
Stephanie Atueyi, Joel Snodgrass, Ryan Casey
Stormwater retention ponds collect many pollutants including trace metals. Aquatic invertebrates ingest some of these contaminants as they feed. A study, conducted ten years ago, measured the quantity of zinc, copper and lead in invertebrates and the sediment of stormwater retention ponds. Invertebrate samples were collected from the same twenty ponds and analyzed for trace metal content (zinc, copper, aluminum, lead, chromium, nickel, arsenic, and cadmium) by ICPMS. Metal concentrations in invertebrates were generally similar to levels measured ten years ago, indicating that continual influx of metals in runoff is not necessarily resulting in increased contamination of biota in ponds. Levels of Cr, As, Cd and Pb were generally similar between invertebrate types, whereas Ni and Al were generally higher in moluscs than odonates and composite invertebrates.