Assessing the toxicity of copper to freshwater Macroinvertebrates

by: Ingrid Schubert

The fate of copper use in the algaecide Cutrine-Plus® and its affect on freshwater macroinvertebrates in an Oak Hill pond receiving Cutrine-Plus® treatment was assessed by analyzing sediments.  Underwater sediments of the Oak Hill pond receiving Cutrine-Plus® treatment, along with three reference ponds (ponds not treated with copper-based compounds), were tested for copper concentrations.  Sediments act as a sink for trace metals such as copper.  A solution of sulfuric/hydrochloric acid solution was used to extract copper from the sediments for analysis of total copper content via atomic absorption spectrophotometry.  I detected a statistically significant difference among ponds in average copper concentration of the sediment samples (K=23.83, p<0.001, d=3).  The average copper concentration of the sediments of the Oak Hill pond receiving Cutrine-Plus® was 0.216 mg/mL, whereas the copper concentrations of the three reference ponds ranged from 0.000 (undetectable) to 0,025 mg/mL.  Copper concentrations in organisms are elevated in areas treated with copper containing algaecides; therefore the analysis of freshwater macroinvertebrates is advised for future research in order to determine whether there is a positive correlation between copper concentrations in sediment and freshwater macroinvertebrates.

Research Advisor: William L. Hallahan, Ph.D., Nazareth College