Air pollutant-enhanced respiratory disease in experimental animals

Studies in animals have shown that a wide range of airborne particulates in cluding cigarette smoke, acid aerosols, metals, organic compounds, and comb ustion products can interfere with the normal defense processes of the lung to enhance susceptibility to respiratory infection or exacerbate allergic diseases. Such detrimental effects are less easy to quantify in humans beca use of the difficulties in obtaining comprehensive exposure history and hea lth status in large populations and because of the inherent dangers of indu cing disease in clinical studies. In this article we describe examples of h ow air pollutants affect lung disease in experimental animal systems. This information can be used to predict the health risk of simple and complex ex posures and to lend insight into the mechanisms of air pollution toxicity.