Examining the Impacts of Antibacterial Personal Care Products on Lake Superior Bacteria

Project Summary

Many personal care products and prescription drugs contain antibacterial chemicals. The presence of low concentrations of these chemicals in wastewater and, ultimately, in lakes and rivers is a topic of recent scientific and media interest. However, not much is known about how these contaminants might affect the environment.

This project looks at one antibacterial chemical, triclosan, which is widely used in hand soaps, toothpaste, and deodorants and other consumer products. The researcher intends to determine the resistance of Lake Superior bacteria to triclosan by sampling bacteria from the Duluth-Superior Harbor and several nearshore locations in Lake Superior. The bacteria will be exposed to very low concentrations of triclosan in the laboratory to note if their growth rates are affected. The researcher also hopes to clarify if low concentrations of triclosan alter the composition of Lake Superior bacterial communities.

The results will be compared to previous studies of Mississippi River bacteria and can be extrapolated to other surface water bodies. The project will help natural resource agencies and scientists decide whether triclosan is an ecological threat that requires more comprehensive study, monitoring, or regulation.