Polycyclic Aromatic Hydrocarbons: Part I. Exposure.

Polycyclic aromatic hydrocarbons (PAH) comprise the largest class of cancer-causing chemicals and are ranked ninth among chemical compounds threatening to humans. Although interest in PAH has been mainly due to their carcinogenic property, many of these compounds are genotoxic, mutagenic, teratogenic, and carcinogenic. They tend to bioaccumulate in the soft tissues of living organisms. Interestingly, many are not directly carcinogenic, but act like synergists. PAH carcinogenicity is related to their ability to bind DNA thereby causing a series of disruptive effects that can result in tumor initiation. Thus, any structural attribute or modification of a PAH molecule that enhances DNA cross linking can cause carcinogenicity. In part I, we review exposure to these dangerous chemicals across a spectrum of use in the community and industry.