Dose-response analysis of ingested benzo(a)pyrene (CAS No. 50-32-8)

The report represents the first part of the Office of Health and Environmental Assessment's dose-response analysis of polycyclic aromatic hydrocarbons (PAHs). Because of the tremendous amount of information bearing on approaches that can be developed to estimate risks from exposures to PAHs, the task is divided into three steps beginning with an analysis of benzo(a)pyrene (BAP), one of the PAHs. The steps are: (1) determining the oral potency slope for benzo(a)pyrene (B(a)P), (2) determining the inhalation potency slope for B(a)P, and (3) determining the potency slopes for other PAHs using a relative potency approach. The focus of the report is on estimating the carcinogenic potency slope of B(a)P by ingestion. The potency slope is used to provide an upper-bound estimate for risk from ingesting low doses of B(a)P. It should be noted that only information relevant to analyzing dose-response relationships by ingestion is analyzed in the report.