Effects of transportation noise and particulate matter on the cardiovascular system: what is the new evidence?

Several decades of research provides compelling evidence that exposure to air pollution causes various diseases. Time series studies in Europe and the USA examined the short term effects on mortality and found about 1% increase for cardiovascular mortality per 10 μg/m3 increase in daily PM2.5 concentration. A comprehensive analysis of 12 European cohort studies addressing the long term effects found a 13% increased risk of coronary events per 5 μg/m3 increase in estimated annual mean PM2.5. Noise exposure triggers an increase in sympathetic responses (fight-flight reactions) and increased release of corticoids (defeat reactions). In 2018 the World Health Organization has published new Environmental Noise Guidelines reporting an 8% increase in risk of incident ischemic heart disease per 10 dB(A) increase in road traffic noise exposure. Transportation noise and air pollution impact health through different pathways, though they also share many biologic pathways. In a recent cohort study, we did not find indications for synergistic or antagonistic effects from combined exposure to noise and air pollution. A study estimating the Environmental Burden of Disease in Europe concluded that ambient air pollution and transportation noise are the two most relevant environmental stressors for the population living in Europe.