Inhalers are the frontline treatment for asthma and COPD, but they come with a steep environmental cost, according to a new UCLA Health study—the largest to date quantifying inhaler-related emissions in the United States. > >Researchers found that inhalers have generated over 2 million metric tons of carbon emissions annually over the past decade, equivalent to the emissions of roughly 530,000 gas-powered cars on the road each year.