Traffic and the heart

Abstract

A small but growing body of evidence suggests that being near traffic may not be good for our hearts. Time series studies have shown associations between various air pollution components and cardiovascular deaths and hospitalizations for the last 15 years or so.1 In these studies, the day-to-day variation in pollution levels is associated with day-to-day variations in cardiovascular death or hospitalization rates. Temporal pollution variations are largely driven by weather patterns, which by themselves may also affect cardiovascular health. How best to disentangle effects of meteorology and air pollution on the cardiovascular system has been the topic of heated debate.2 At current pollution levels in highly developed regions of the world, the estimated effects on cardiovascular mortality and morbidity are modest even on ‘high’ pollution days, being in the order of perhaps 5–10% excursions over baseline—but it has been impossible to identify a threshold below which no effect occurs, and all of these small, day-to-day health impacts add up to considerable numbers over years.3,4 Cohort studies conducted in the US have provided evidence that long-term exposure especially to very small particles in the air, leads to reduced life expectancy as a result of increased cardio-respiratory mortality.5,6 These studies have had a major impact on regulatory advice and decisions … Corresponding author. Tel: +31 30 2539494/90; fax: +31 30 2539499. E-mail address : b.brunekreef{at}iras.uu.nl