Assessing Effects of Emerging Contaminants on Sentinel Species

Chemicals used extensively and intensively in our technological society are currently predicted to have surpassed the 100,000 mark in numbers and depending on their properties, modes, and quantity of use, a large number of these chemicals can reach the environment and have unpredictable but potentially harmful environmental and health impacts. Accurate methods of monitoring the levels of these chemicals, an understanding of their potential to damage natural inhabitants to these waters, and the ability to properly develop a risk assessment strategy are all critical pieces to the maintenance of a healthy aquatic ecosystem that does not pose a threat to human safety. Current research in our laboratories has identified several emerging contaminants in Lake Erie beach waters of Presque Isle State Park, including fluoxetine, triclosan, estradiol, and diuron, as well as the artificial sweetener sucralose. All of these chemicals have been shown to have negative health consequences in organisms from bacteria to humans. For most of these, the levels in the Park approach or exceed levels known to cause harm to aquatic species. We have also demonstrated the ability of these chemicals of concern to have genotoxic (and often synergistic) effects on sentinel species, including E. coli. The aims of this study were extend our previous work through three objectives:

• Monitoring levels of contaminants in Lake Erie beach surface waters over a 15-month time period.
• Extending previous findings that have established a correlation between DNA damage and contaminant concentrations to biologically relevant and commonly used laboratory species
• Examining existing levels of DNA damage in environmental species through a novel application of an established methodology in a new direction (unprecedented work in the literature)

 The chosen experimental methods (ELISA assay and Comet Assay) have a well-established history of success for the examination of the presence and genotoxic potential of chemicals of concern in the environment. The findings obtained from the objectives proposed in this research have complemented existing data from our laboratories and that from others on the effects of chemicals of concern in the environment and their potential to cause DNA damage in humans. Lastly, the proposed research here shows an important, and as yet unpublished, combination of these established methods (Comet-FISH assay) to create new knowledge to answer several important questions relating to water quality and the potential impact to human health. The objectives of the research allowed us to accomplish several goals. First, we examined the levels of several emerging contaminants in Lake Erie Beach waters of Presque Isle State Park including fluoxetine, triclosan, estradiol, and diuron. In the laboratory, we tested the extent to which these chemicals can act negatively on standard sentinel species, including Euglena and Chlamydomonas through a DNA damage assay. From these data, we are working to provide a clearer picture as to levels, potential hazards of, and need for risk assessment management of these chemicals of concern in the Lake Erie beach waters of Presque Isle State Park.