A road forward to improve public health.

Air quality has improved in many countries, including the United States, during the past few decades.1,2 Importantly, these gains have translated into observable health benefits. Reductions in fine particulate matter (PM) have significantly contributed to the increase in life expectancy in the United States since the 1980s.2 However, the burden of adverse health effects caused by high levels of air pollution continues to grow throughout many regions of the world. Outdoor air pollution ranks as the 8th-leading risk factor for death among high-income countries.3 Estimates are that anthropogenic fine PM contributes to 3.5 million cardiopulmonary deaths globally per year.4 Perhaps not well appreciated is the reality that cardiovascular (CV) deaths likely constitute the largest portion of this mortality.1