Impacts of wastewater discharges on freshwater mussels in a tributary of the Grand River, Ontario

Session: 58. - Cities on the Shore: Urbanization as a Growing Threat to Nearshore Ecosystem Health

Erin Hayward, Trent University, [email protected]
Patricia Gillis, Environment and Climate Change Canada, [email protected]
James Bennet, Environment and Climate Change Canada, [email protected]
Chris Metcalfe, Trent University, [email protected]
Ryan Prosser, University of Guelph, [email protected]

Abstract

Population abundance, and species diversity of aquatic organisms have been found to be negatively impacted by the release of municipal wastewater. Exposures to contaminants of emerging concern (CECs) of wastewater origin have been associated with feminization of fish and effects on the immune system of freshwater mussels. In some areas of the Grand River watershed, there are abundant populations of freshwater mussels, including several species at risk (SAR). The impact of wastewater discharged into Boston Creek, a tributary of the Grand River, was investigated in partnership with a small rural community of approximately 300 people. The lagoon water met Environment Canada guidelines for wastewater quality and did not cause acute toxicity to Oncorhynchus mykiss. However, exposures of glochidia (mussel larvae) of Lampsilis fascilola and Villosa iris to undiluted lagoon water slightly reduced survival. During the fall discharge from the lagoon, adult Lasmigona costata were caged in Boston Creek upstream and downstream of the lagoon discharge. Mussel tissues were analyzed for various biomarkers of contaminant exposure. Passive samplers were also deployed to characterize CEC exposure, including caffeine, artificial sweeteners, estrogens and selected pharmaceuticals. Some of these results will be presented and discussed in relation to the quality of mussel SARs habitat in the Grand River watershed.

1. Keyword
unionids

2. Keyword
environmental contaminants

3. Keyword
Grand River

4. Additional Keyword
First Nations

5. Additional Keyword
Species at Risk

6. Additional Keyword
CECs