Health Effects of Repeated Exposure to Low Levels of Concentrated Ambient Particles in Healthy Young Volunteers

Purpose: To determine whether 3-day consecutive exposures to levels of fine particulate matter (PM2.5) that are close to the current 24-hr national standard will cause changes in inflammatory and cardiopulmonary endpoints in healthy young individuals. Participants: 20 healthy males and females aged 18-35 years. Procedures (methods): Subjects will be randomly exposed to three consecutive days of filtered air (4 hr/day) and three consecutive days of PM2.5 (approximately 35 µg/m3; 4 hr/day) in an exposure chamber. Blood collection for inflammatory factors such as C-reactive protein (CRP), clotting factors; heart rate variability (HRV); spirometry; and a symptom questionnaire will be conducted before and after each exposure.