Air pollution is a major environmental risk factor. There is accumulating evidence that air pollution could induce elevated blood pressure and potentiate hypertension. Acute elevations in the outdoor air pollution levels can trigger immediate or shortly delayed increases in arterial blood pressure. Moreover, few studies suggest that short-term increases in the levels of particulate and gaseous pollutants could lead to an acute onset of hypertension. Prolonged exposure to outdoor air pollution is associated with elevated blood pressure. Furthermore, some longitudinal studies have linked long-term exposure to air pollution with the incidence of hypertension. Various components of air pollution, such as inhalable particulate matter (PM2.5, PM10), nitrogen oxides, sulfur dioxide, and ozone, have shown associations with blood pressure in some studies. The hypothesized underlying mechanisms include inflammatory reactions and oxidative stress in lungs and in systemic circulation, imbalance of autonomous nervous system, and pathologic changes in vascular endothelium. In addition to “traditional” susceptible groups such as elderly individuals or patients with chronic diseases, children and pregnant women could be especially susceptible to the adverse effects of air pollution. The interplay of air pollution with the related environmental exposures, such as traffic noise and climate change, should be investigated further.
Part of the book: Blood Pressure