Nearly four in 10 people in the US are exposed to unhealthy levels of air pollution, a new report has found. Four of the five most polluted cities are in California, where wildfires, drought and extreme heat are driving the rise in hazardous air quality.
More than 131 million people are exposed to harmful ozone and particle (PM 2.5) pollution, according to the American Lung Association’s annual State of the Air report. That figure, which incorporates new, more stringent federal standards for particle pollution, represents an 11.7 million increase from the previous year.
