Objective: We examined whether more precise exposure measures would better detect associations between traffic-related pollution, elemental carbon (EC), nitrogen dioxide (NO2), and heart rate variability (HRV).
Methods: Repeated 24-hour personal and ambient pm2.5, EC, and NO2 were measured for 30 people living in Atlanta, GA. The association between HRV and either ambient concentrations or personal exposures was examined using linear mixed effects models.
Results: Ambient pm2.5, EC, NO2, and personal pm2.5 were not associated with HRV. Personal EC and NO2 measured 24 hours before HRV were associated with decreased RMSSD, PNN50, and HF and with increased LF/HF. RMSSD decreased by 10.97% (95% confidence interval: −18.00 to −3.34) for an inter-quartile range change in personal EC (0.81 μg/m3).
Conclusions: Results indicate decreased vagal tone in response to traffic pollutants, which can best be detected with precise personal exposure measures.
From the Department of Environmental Health, Harvard School of Public Health, Boston, Mass.
CME Available for this Article at ACOEM.org
Helen Suh and Antonella Zanobetti have no financial interest related to this research.
The JOEM Editorial Board and planners have no financial interest related to this research.
Address correspondence to: Helen H. Suh, ScD, Department of Environmental Health, Harvard School of Public Health, 401 Park Drive, Landmark West 404G, PO Box 15677, Boston, MA 02215; E-mail: firstname.lastname@example.org.