Abstract Pentachlorobenzene is included on the List of Priority Substances to be assessed under the Canadian Environmental Protection Act. Available data were critically evaluated to assess the potential human health effects of exposure to pentachlorobenzene in the Canadian environment. Data on the potential carcinogenicity of pentachlorobenzene have not been identified. The estimated average daily intakes of pentachlorobenzene for various age groups in the general population in Canada are approximately 5 to 1,000 times less than the tolerable daily intake derived from oral studies in experimental animals.