Association of heart rate variability in taxi drivers with marked changes in particulate air pollution in Beijing in 2008

Environ Health Perspect. 2010 Jan;118(1):87-91. doi: 10.1289/ehp.0900818.


Background: Heart rate variability (HRV), a marker of cardiac autonomic function, has been -associated with particulate matter (PM) air pollution, especially in older patients and those with cardio-vascular diseases. However, the effect of PM exposure on cardiac autonomic function in young, healthy adults has received less attention.

Objectives: We evaluated the relationship between exposure to traffic-related PM with an aerodynamic diameter <or= 2.5 microm (PM2.5) and HRV in a highly exposed panel of taxi drivers.

Methods: Continuous measurements of personal exposure to PM2.5 and ambulatory electrocardiogram monitoring were conducted on 11 young healthy taxi drivers for a 12-hr work shift during their work time (09002100 hr) before, during, and after the Beijing 2008 Olympic Games. Mixed-effects regression models were used to estimate associations between PM2.5 exposure and percent changes in 5-min HRV indices after combining data from the three time periods and controlling for potentially confounding variables.

Results: Personal exposures of taxi drivers to PM2.5 changed markedly across the three time -periods. The standard deviation of normal-to-normal (SDNN) intervals decreased by 2.2% [95% confidence interval (CI), 3.8% to 0.6%] with an interquartile range (IQR; 69.5 microg/m3) increase in the 30-min PM2.5 moving average, whereas the low-frequency and high-frequency powers decreased by 4.2% (95% CI, 9.0% to 0.8%) and 6.2% (95% CI, 10.7% to 1.5%), respectively, in association with an IQR increase in the 2-hr PM2.5 moving average.

Conclusions: Marked changes in traffic-related PM2.5 exposure were associated with altered cardiac autonomic function in young healthy adults.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Air Pollution / adverse effects*
  • Air Pollution / prevention & control
  • Analysis of Variance
  • Automobile Driving*
  • Autonomic Nervous System / drug effects
  • Autonomic Nervous System / physiopathology
  • China
  • Electrocardiography, Ambulatory
  • Female
  • Heart Rate / physiology*
  • Humans
  • Male
  • Occupational Exposure*
  • Particulate Matter / toxicity
  • Regression Analysis
  • Risk Factors
  • Vehicle Emissions / toxicity*


  • Particulate Matter
  • Vehicle Emissions