Respiratory Epithelial Penetration and Clearance of Particle-Borne Benzo[a]pyrene

Dr. Gerde and colleagues at the Lovelace Respiratory Research Institute examined the effects of organic compounds in diesel exhaust such as genotoxic polynuclear aromatic compounds (PAHs). The investigators removed most of the organic compounds from diesel exhaust particles and bound radioactive Benzo[a]pyrene (BaP), a type of PAH is known to cause cancer in laboratory animals, to them. They exposed the lower respiratory tract of three dogs to the particles and measured the levels of particle-bound BaP and free BaP released from particles in the peripheral region of the lungs. After six months, the investigators exposed only the trachea to the particle-bound BaP to determine the long term stability of BaP on the particles.