Medium-term exposure to traffic-related air pollution and markers of inflammation and endothelial function

Environ Health Perspect. 2011 Apr;119(4):481-6. doi: 10.1289/ehp.1002560. Epub 2011 Feb 24.


Background: Exposure to traffic-related air pollution (TRAP) contributes to increased cardiovascular risk. Land-use regression models can improve exposure assessment for TRAP.

Objectives: We examined the association between medium-term concentrations of black carbon (BC) estimated by land-use regression and levels of soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1), both markers of inflammatory and endothelial response.

Methods: We studied 642 elderly men participating in the Veterans Administration (VA) Normative Aging Study with repeated measurements of sICAM-1 and sVCAM-1 during 1999-2008. Daily estimates of BC exposure at each geocoded participant address were derived using a validated spatiotemporal model and averaged to form 4-, 8-, and 12-week exposures. We used linear mixed models to estimate associations, controlling for confounders. We examined effect modification by statin use, obesity, and diabetes.

Results: We found statistically significant positive associations between BC and sICAM-1 for averages of 4, 8, and 12 weeks. An interquartile-range increase in 8-week BC exposure (0.30 μg/m3) was associated with a 1.58% increase in sICAM-1 (95% confidence interval, 0.18-3.00%). Overall associations between sVCAM-1 and BC exposures were suggestive but not statistically significant. We found a significant interaction with diabetes-where diabetics were more susceptible to the effect of BC-for both sICAM-1 and sVCAM-1. We also observed an interaction with statin use, which was statistically significant for sVCAM-1 and suggestive for sICAM-1. We found no evidence of an interaction with obesity.

Conclusion: Our results suggest that medium-term exposure to TRAP may induce an increased inflammatory/endothelial response, especially among diabetics and those not using statins.

Publication types

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

MeSH terms

  • Aged
  • Aged, 80 and over
  • Air Pollutants / analysis*
  • Air Pollutants / toxicity
  • Boston / epidemiology
  • Endothelium / drug effects*
  • Endothelium / metabolism
  • Endothelium / physiopathology
  • Humans
  • Inflammation / chemically induced
  • Inflammation / metabolism
  • Intercellular Adhesion Molecule-1 / metabolism
  • Male
  • Middle Aged
  • Regression Analysis
  • Soot / analysis*
  • Soot / toxicity
  • Vascular Cell Adhesion Molecule-1 / metabolism
  • Vehicle Emissions / analysis*
  • Vehicle Emissions / toxicity


  • Air Pollutants
  • Soot
  • Vascular Cell Adhesion Molecule-1
  • Vehicle Emissions
  • Intercellular Adhesion Molecule-1