The document discusses reserves of heavy oil and concentrations of toxicants in the environment and their environmental impacts. It analyzes related research studies and finds that even small concentrations of toxicants in the environment can accumulate in living organisms permanently living there. For example, the Hanford nuclear plant illustrates how organisms concentrated toxicants released from the plant. The document also examines heavy oil reserves in different regions and how they contain tar-asphaltene compounds and heavy metals.