Acute Health Effects of Commuters’ Exposure to Air Pollution

Abstract

ISEE-0670 Background and Objective: People spend a significant amount of time in traffic, during which they are exposed to high levels of air pollution. Very few studies measured acute health effects after exposure in traffic. The TRAVEL study was designed to study exposure and related acute health effects of people commuting by bike, car and bus. Methods: From June 2007 till June 2008 volunteers repeatedly travelled for two hours by bus, car or bike on a fixed route in the city of Arnhem. During the commute we measured the PM10 concentration using Harvard Impactors and Particle Number Count (PNC) using a portable condensation particle counter (TSI CPC3007). Soot was measured on the PM10 filter using a smoke stain reflectometer. Before and six hours after exposure we measured nitrogen oxide in exhaled air (FeNO) and high-sensitivity C-reactive protein (CRP) plasma levels in the volunteers. Results: During the 47 measurement days we collected 357 pre and post health measurements of 34 healthy, non-smoking, adult volunteers. Two hour mean exposure to PNCs ranged from 14000 to 91000 particles/cm3 (mean 40000 particles/cm3), PM10 exposure ranged from 16 to 423 μg/m3 (mean 54 μg/m3), and soot exposure from 1.6 to 31 ± 10-5/m (mean 7.2 ± 10−5/m). FeNO levels were on average 19 ppb, the difference in post and pre FeNO ranged from −35 to 10 (mean: −1.5 ppb). CRP levels were on average 1.21 mg/L, the difference in post and pre CRP ranged from −2.4 to 6.5 (mean: 0.0 mg/L). Using mixed model analysis, we found no associations between exposure to PNC, PM10 and soot and differences in post-pre levels of FeNO and CRP. Conclusion: Commuters’ exposure to PNC, PM10 and soot was not associated with FeNO, a marker of airway inflammation, and plasma CRP, a marker of systemic inflammation.