Unit of Environmental Epidemiology, Institute of Environmental Medicine, Nobels väg 13, Box 210 Karolinska Institutet, SE-171 77 Stockholm, Sweden. Sviatlana.Panasevich@ki.se
Exposure to elevated levels of ambient air pollutants can lead to adverse cardiovascular effects. Potential mechanisms include systemic inflammation and perturbation of the coagulation balance.
To investigate long- and short-term effects of air pollution exposure on serum levels of inflammatory (IL-6, TNF-alpha and CRP) and coagulation (fibrinogen and PAI-1) markers relevant for cardiovascular pathology.
The study group consisted of a population sample of 1028 men and 508 women aged 45-70 years from Stockholm. Long-term air pollution exposure was assessed using spatial modelling of traffic-related NO(2) and heating-related SO(2) emissions at each subject's residential addresses over retrospective periods of 1, 5 and 30 years. Short-term exposure was assessed as averages of rooftop measurements over 12-120 h before blood sampling.
Long-term exposures to both traffic-NO(2) and heating-SO(2) emissions showed consistent associations with IL-6 levels. 30-year average traffic-NO(2) exposure was associated with a 64.5% (95% CI 6.7% to 153.8%) increase in serum IL-6 per 28.8 microg/m(3) (corresponding to the difference between the 5th and 95th percentile exposure value), and 30-year exposure to heating-SO(2) with a 67.6% (95% CI 7.1% to 162.2%) increase per 39.4 microg/m(3) (5th-95th percentile value difference). The association appeared stronger in non-smokers, physically active people and hypertensive subjects. We observed positive non-significant associations of inflammatory markers with NO(2) and PM(10) during 24 h before blood sampling. Short-term exposure to O(3) was associated with increased, and SO(2) with decreased, fibrinogen levels.
Our results suggest that exposure to moderate levels of air pollution may influence serum levels of inflammatory markers.