Polycyclic aromatic hydrocarbons: Evaluation of risks to health from environmental exposure in Canada

Abstract Polycyclic aromatic hydrocarbons (PAHs) are included on the List of Priority Substances to be assessed under the Canadian Environmental Protection Act. On the basis of available results of carcinogenicity bioassays, the 5 PAHs considered in this assessment [benzo(a)pyrene, benzo(b)fluoranthene, benzo(j)fluoranthene, benzo(k)fluoranthene and indeno(1,2,3‐cd)pyrene] have been classified as “probably carcinogenic to humans”. Based on comparison of levels of PAHs in ambient air in Canada with estimates of their carcinogenic potency by two limited approaches, the priority for analysis of options to reduce exposure of the general population is considered to be moderate to high, compared to that of other substances assessed in the Priority Substances program. Recommendations for research to enable a more complete assessment are included.