Air Pollution

HEI Research Report 192 describes a multicenter study by John Balmes at the University of California–San Francisco, Phil Bromberg at the University of North Carolina–Chapel Hill, and Mark Frampton at the University of Rochester, New York. The study was designed to test whether ozone has short-term cardiovascular effects at present-day ambient levels. It evaluated respiratory and cardiovascular outcomes in 87 healthy participants (60 years old on average) who were exposed to 0, 70, or 120 ppb ozone for 3 hours while exercising moderately.

Research Report 191 describes a study by Allison Fryer and colleagues that addressed how exposure to ozone affects the immune and physiological responses in guinea pigs. In her study, Dr. Fryer focused on eosinophils, white blood cells that play an important role in inflammation, allergies, and allergic asthma, and can modify the airway response to ozone inhalation. This study tested a novel hypothesis: that allergic guinea pigs react differently to ozone than normal animals because of newly formed eosinophils that migrate from bone marrow to the lungs.