Bailus Walker Jr., PhD, MPH, Department of Community and Family Medicine, College of Medicine, Howard University, Washington, DC, USA.
Charles Mouton, MD, MS, Department of Community and Family Medicine, College of Medicine, Howard University, Washington, DC, USA.

In the late 1990s, it became increasingly clear that air pollution, even at the lower ambient concentrations prevalent in many urban areas, is associated with increased mortality and other serious health effects. More recently, considerable research has focused on particulate air pollution as studies have linked a growing number of health effects to fine particles. Hundreds of studies now indicate that breathing fine particles discharged by vehicles, factories, and power plants can trigger a cardiac event and exacerbate respiratory disease in vulnerable populations. Older adults are one subgroup considered more susceptible to the effects of airborne particles. This sensitivity can be attributed to a number of factors including loss of pulmonary functional reserve and compensation due to age or disease. Although a number of mechanisms have been proposed to explain the adverse impact of particles on cardiovascular health, many questions remain. Their answers will require further transdisciplinary research.
Key words: heart disease, air pollution, smog, particulates, older adults.