This course discusses various types of contaminants (metal, organic pollutants, pesticides, pharmaceuticals, flame-retardants, micro-plastics, nano-materials) and their impact on the environment. Lectures will cover sources, transport and fate of these contaminants in various environmental media (air, water), degradation mechanisms, uptake into biological systems, and toxicity. Case studies such as pollutants in Arctic ecosystems and the potential risks they pose to the health of indigenous people will be examined. Tutorial discussions of current scientific articles will complement lectures.