Assessing adverse effects of emerging chemical contaminants on fishes of commercial, aboriginal, and recreational value to Canadians

Description

Human activities result in the discharge of a diversity of chemicals into aquatic ecosystems. While some of these substances have been well characterized with respect to their adverse effects on aquatic organisms including fishes, the biological impact of many chemicals remains unknown. Emerging contaminants, including pharmaceuticals and personal care products, nanoparticles, and brominated flame retardants are ubiquitously present in the environment, and have been identified as potential risks to aquatic wildlife. Large amounts of these chemicals can enter surface waters through wastewater effluents, particularly for communities that discharge their sewage directly to surface waters or lagoons with minimal treatment, which is the case in many northern and rural communities.

Currently, strategies for the assessment of the risks associated with the exposure to environmental contaminants are based on standard laboratory model species. However, it is not clear whether such an approach is protective against adverse effects of emerging contaminants on native species of fishes because our understanding of the sensitivity and vulnerability of such species is very limited. Therefore, the main objective of this research is to generate novel knowledge and approaches to enable prospective and objective assessments of risks that emerging contaminants pose to freshwater fishes of commercial, cultural, and recreational importance to Canadians, and that serve as indicators for the health of ecosystems. Specifically, this study will focus on five emerging contaminants and a complex municipal wastewater effluent that are representative of priority contaminants in Canadian water bodies. Target fish species are rainbow trout (Coregonus clupeaformis), the endangered white sturgeon (Coregonus clupeaformis), northern pike (Coregonus clupeaformis), and lake whitefish (Coregonus clupeaformis). Test chemicals include the contraceptive 17a-ethynylestradiol, the antidepressant Fluoxitine (Prozac), the brominated flame retardant hexabromocyclododecane, short chain chlorinated paraffins, silver nanoparticles, as well as a municipal effluent.

The research addresses effects on survival, growth, and development of early life stages, impacts on the reproductive endocrine system of sexually maturing life stages, as well as assessment of the specific mechanisms of adverse effects by use of open format “omics” technologies. Furthermore, in vitro tissue explant systems will be developed for the four target species as a high-throughput approach to predict the specific toxicities of environmental contaminants to native fishes. Together, this information will be used to develop a predictive toxicological model that will allow for prediction of biologically relevant outcomes from sub-lethal toxicity initiating events and species-specific high-throughput, in vitro approaches. This work will establish novel approaches to aid scientists and policy-makers with unbiased assessment of risks that emerging contaminants pose to native fishes. While focusing on six representative chemicals/matrices, the approaches will be transferable and applicable to other contaminants of concern.

Program Name

National Contaminants Advisory Group (NCAG)

Year(s)

2014 - 2017

Ecoregion(s)

National

Principal Investigator(s)

Markus Hecker
Associate Professor and Canada Research Chair
University of Saskatchewan, Saskatoon, Saskatchewan

Team Member(s)

Steve B. Wiseman, University of Saskatchewan, Saskatoon, Saskatchewan

Paul D. Jones, University of Saskatchewan, Saskatoon, Saskatchewan

John P. Giesy, University of Saskatchewan, Saskatoon, Saskatchewan

Song Tang, University of Saskatchewan, Saskatoon, Saskatchewan

Collaborative Partner(s)

Henner Hollert, RWTH Aachen University, Germany

Edward Perkins, US Army Engineer Research and Development Center, USA