Grant: Research Tools and Instruments - Category 1 (<$150,000)

A micro-respirometry system will be used by the applicant and three collaborators at Wilfrid Laurier in a wide range of applications to determine how aquatic organisms respond to metals, pesticides, endocrine disrupting compounds, and emerging contaminants such as nanoparticles, at the sub-cellular, cellular and whole animal level. The instrument will initially be used to measure oxygen consumption of mitochondria to better understand how exposure to 3-trifluoromethyl-4-nitrophenol (TFM), the pesticide used to control invasive sea lamprey populations in the Great Lakes, interferes with fuel (ATP) production in lampreys, as well as non-target fishes which are often transiently exposed to this chemical during TFM treatments. As the mitochondria are also targets of metals and metabolic wastes such as ammonia, mitochondrial respiration studies will determine how such toxicants interfere with ATP production in different fishes. The micro-respirometry system will also be used to elucidate how respiratory processes are compromised in developing fish embryos and larvae when exposed to endocrine disrupting substances, which are contaminants found in many waters. The metabolic activity of cultured cells (e.g. brain, gills, liver) will also be measured with the micro-respirometry system to assess cell viability and physiological stress during exposure to metals, ammonia and nanoparticles. By developing such a non-lethal means of testing cell viability and physiological stress, it will be possible to more effectively track how cells respond to environmental contaminants in ecotoxicology studies. To better understand how metals compromise gas exchange and metabolism in invertebrates, oxygen consumption will also be measured in model organisms such as the common water flea, which is commonly used to monitor the toxicity of municipal and industrial effluents. The requested instrument is not available at Wilfrid Laurier, and will fulfill the research needs of HQP in the four laboratories that presently belong to Laurier's emerging Fish Physiology Research Group.