Combustion-Source Particulate Air Pollution and Human Health. C. Arden Pope, III, Brigham Young University
Numerous studies have reported adverse health effects associated with particulate air pollution. This paper explores the overall evidence that particulate pollution is an important risk factor for cardiopulmonary disease, focusing on the concern that the observed health effects may be due to a common confounder. This paper also evaluates the constituent or characteristic of this pollution that may be most important in defining its toxicity, with special attention to combustion-source particulate pollution and aerosol acidity. There is no obvious single common confounder, including cigarette smoking, socioeconomic factors, weather and seasonal factors, sulfur dioxide (SO2) or ozone (O3), that would explain the overall epidemiologic evidence. An overall evaluation of the epidemiologic evidence suggests that combustion-source particles have larger effects on human health than natural occurring particles. It is uncertain if the relative importance of combustion-source particles is due to their relative small size, their chemical composition, or both. However particulate acidity does not appear to be a necessary constituent or characteristic of combustion-source particle pollution that defines its toxicity.