This course discusses various types of contaminants (metals, persistent organic pollutants, emerging contaminants, pesticides, pharmaceuticals, flame-retardants, micro-plastics, nano-materials, etc.) and their impacts on the environment. Lectures cover sources, transport and fate of these contaminants in various environmental media (air, water, and soil/sediment), degradation mechanisms, uptake into biological systems, and toxicity. A number of case studies such as pollutants in Arctic ecosystems and the potential risks they pose to the health of Indigenous People and the role of science in informing policy addressing pollutants will be examined. Class and group activities during tutorials, including discussions of current scientific articles, will complement lectures.