Effects of particulate air pollution on blood pressure in a highly exposed population in Beijing, China: a repeated-measure study

Environ Health. 2011 Dec 21;10:108. doi: 10.1186/1476-069X-10-108.

Abstract

Background: Particulate Matter (PM) exposure is critical in Beijing due to high population density and rapid increase in vehicular traffic. PM effects on blood pressure (BP) have been investigated as a mechanism mediating cardiovascular risks, but results are still inconsistent. The purpose of our study is to determine the effects of ambient and personal PM exposure on BP.

Methods: Before the 2008 Olympic Games (June 15-July 27), we examined 60 truck drivers and 60 office workers on two days, 1-2 weeks apart (n = 240). We obtained standardized measures of post-work BP. Exposure assessment included personal PM(2.5) and Elemental Carbon (EC, a tracer of traffic particles) measured using portable monitors during work hours; and ambient PM(10) averaged over 1-8 days pre-examination. We examined associations of exposures (exposure group, personal PM(2.5)/EC, ambient PM(10)) with BP controlling for multiple covariates.

Results: Mean personal PM(2.5) was 94.6 μg/m(3) (SD = 64.9) in office workers and 126.8 (SD = 68.8) in truck drivers (p-value < 0.001). In all participants combined, a 10 μg/m(3) increase in 8-day ambient PM(10) was associated with BP increments of 0.98 (95%CI 0.34; 1.61; p-value = 0.003), 0.71 (95%CI 0.18; 1.24; p-value = 0.01), and 0.81 (95%CI 0.31; 1.30; p-value = 0.002) mmHg for systolic, diastolic, and mean BP, respectively. BP was not significantly different between the two groups (p-value > 0.14). Personal PM(2.5) and EC during work hours were not associated with increased BP.

Conclusions: Our results indicate delayed effects of ambient PM(10) on BP. Lack of associations with exposure groups and personal PM(2.5)/EC indicates that PM effects are related to background levels of pollution in Beijing, and not specifically to work-related exposure.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adult
  • Blood Pressure*
  • Cardiovascular Diseases / chemically induced*
  • China
  • Cities
  • Environmental Exposure*
  • Female
  • Heart Rate*
  • Humans
  • Male
  • Particulate Matter / analysis
  • Particulate Matter / toxicity*
  • Time Factors
  • Young Adult

Substances

  • Particulate Matter