Their work informed air-pollution policy not only in the United States, but also around the world. “To be blunt, they are lying.”The World Health Organization (WHO) estimates that air pollution causes 7 million premature deaths each year, globally. But in the United States, an alarming trend is emerging. Some of the threats to lung health come from well-known air pollutants such as ozone and particulate matter generated by vehicles. “We have a rapidly growing source of air pollution that our main policy tool is not equipped to deal with,” Burke says.