Superfund Research Program
Environmental PAH Mixtures as Skin and Transplacental Carcinogens
Project Leader: William M. Baird
Grant Number: P42ES016465
Funding Period: 2009-2013
Project Summary (2009-2013)
Polycyclic aromatic hydrocarbons (PAHs) are a re-emerging class of environmental pollutants formed from incomplete combustion of fossil fuels (diesel or gasoline exhaust, burning of coal, petroleum or tobacco). Increasing energy needs world-wide suggest PAH concentrations will be increasing over the next quarter century. PAHs produce cancers at multiple sites in animal models and were the first class of chemicals identified as environmental carcinogens. Even so, relatively little is known about critical aspects of PAH-dependent carcinogenesis. Much of the work to date has, for simplicity, employed a single PAH, such as benzo[a]pyrene (BaP) or dibenzo[a,l]pyrene (DBP) rather than actual environmental mixtures. In this project, Dr. Baird and his research team compare the carcinogenicity of PAH mixtures, from locations where high human exposures are known or suspected, to BaP and DBP in two cancer models. The first models skin cancer, which is rapidly increasing in incidence world-wide. The second model examines transplacental lymphorna, lung, and liver cancer. In studying these environmentally relevant PAH mixtures, the researchers address critical questions of mechanism and the potential for intervention. The common mechanistic goals in both cancer models allow a high degree of integration.