The Analysis and Assessment of Exhaled VOCs in Adults under Ambient Ozone Exposure

Rapidly monitoring and accurately assessing the direct
impacts
of air pollution on human health is a long–standing challenge.
Exhaled breath analysis, as a real–time and sensitive human
biomonitoring technique, is causing significant concerns. This study
aims to analyze and assess volatile organic compounds (VOCs) in human
exhaled breath under ambient ozone (O3) exposure. A comprehensive
correlation analysis involving 288 VOCs are identified in the exhaled
breath of healthy adults (n = 1130), uncovering 12
VOCs including methanol, propyne, and 1–butene etc. that show
strong exposed correlations with ambient O3 levels. Nonlinear
modeling indicated the dose–response commencing at O3 concentrations as low as 58 μg/m3. Moreover,
the presence of PM2.5 significantly exacerbates the effect
of O3 on the filtered 12 VOCs. The most pronounced interplay
is observed at 140 μg/m3 for O3 and 150
μg/m3 for PM2.5. Finally, an in-vivo study
using rats validates the result, with all of the 12 exhaled breath
biomarkers exhibit obvious differences (O3 exposure group
vs control group). This work demonstrates direct evidence that ambient
O3 pollution impacts on human exhaled VOCs, and also offers
valuable insights for establishing O3 exposure thresholds.