A new report finds air pollution reduces global life expectancy by 2.3 years — slightly more than being a smoker. The study by the Energy Policy Institute at the University of Chicago concludes fine particulate air pollution from vehicles, industrial emissions, wildfires and other sources are “the greatest external threat to public health.” In South Asia, air pollution cuts life expectancy by an average of five years, with the air quality in New Delhi leading to a loss of more than 10 years on average.