Sediment quality classification in freshwater lakes predicted by the history of treatment with copper‐based aquatic algaecides.

This article focuses on the relationship between historical use of copper-based aquatic algaecides and copper accumulation in freshwater lake sediments in New York State. The study analyzed sediment samples from 29 lakes with varying histories of copper treatment and found that lakes treated with copper algaecides have significantly higher sediment copper concentrations, particularly in the sublittoral zone, compared to untreated lakes. A positive correlation was quantitatively established between the number of copper algaecide applications and sediment copper levels, enabling the identification of treatment thresholds that may pose ecological risks to benthic organisms. These findings support the use of sediment copper concentration and treatment history as screening tools for regulatory agencies to assess and manage the ecological risks of future copper-based algaecide applications.