Indirect-acting carcinogens

•      Polycyclic aromatic hydrocarbons (PAH)

•      Produced by incomplete combustion of organic materials

•      Present in chimney soot, charcoal grilled meats, auto exhaust, cigarette smoke

                                       Human exposure to PAH

•      Benzo(a)pyrene – 1300 tons per year into atmosphere

•      In clean air – 0.02 ug/day inhaled

•      In polluted air – 1.5 ug/day inhaled