The modifying effects of temperature on contaminant toxicity in Artic and temperate fish species

Description

The presence of contaminants in the Arctic has been well-documented, however the majority of Arctic toxicology research has focused on mercury and persistent organic pollutants such as PCBs and dioxins. To date, the risk that other environmental contaminants pose to Arctic species has been estimated based on research on temperate species, even though the sensitivity and response of Arctic animals may differ. Water temperature has a profound effect on fish physiology, yet few studies have examined how temperature influences the chronic toxicity of priority pollutants in either Arctic or temperate species. Metals such as cadmium and copper, two priority pollutants in the Arctic region, are known to be toxic to different fish species.

This research will examine the toxicity of cadmium and copper on two species of Arctic fish (Arctic Charr and Lake Whitefish) and one temperate fish (Rainbow Trout) at three different temperatures (5, 10 and 15°C). The main goals are to determine the sensitivities of Arctic fish to chronic cadmium and copper exposures, and examine the influence of water temperature on the uptake and response of these fish to contaminant exposure. For each objective, we will assess the growth rate and impacts on the gill, kidney, and liver through microscopic analysis of tissues (histology), swimming performance, metabolism, and urinalysis. Impacts on sensory tissue will be assessed using behavioural and olfactory tests. Determining how temperature modifies toxicity within a species, and the relative sensitivity of Arctic versus temperate species to contaminants, will be important for extrapolating existing toxicological data to Arctic species. This has implications for predicting changes in toxicity in Arctic regions under climate change.

Program Name

National Contaminants Advisory Group (NCAG)

Year(s)

2017 – 2020

Ecoregion(s)

Arctic: Eastern Arctic, Western Arctic, Arctic Archipelago

Atlantic: NL- Labrador Shelves

Principal Investigator(s)

Dr. Joanna Wilson
Associate Professor, Department of Biology
McMaster University