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).
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.
, 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
Results indicate decreased vagal tone in response to traffic pollutants, which can best be detected with precise personal exposure measures.