Inhalers Contribute Significantly to US Environmental Carbon Footprint

A new study by UCLA Health has quantified inhaler-related emissions in the United States, revealing that they generate over 2 million metric tons of carbon emissions annually, equivalent to the emissions of roughly 530,000 gas-powered cars on the road each year. The study, published in JAMA, analyzed emissions from three types of inhalers approved for asthma or COPD from 2014 to 2024 and found that metered-dose inhalers were the most environmentally harmful, accounting for 98 percent of emissions over the ten-year period. Metered-dose inhalers contain hydrofluoroalkane (HFA) propellants, which are potent greenhouse gases. Researchers plan to expand their research to examine inhaler-related emissions in specific patient populations and compare clinical outcomes between lower- and higher-emission inhalers.

Key Takeaways:

• Inhalers generate over 2 million metric tons of carbon emissions annually in the United States, equivalent to the emissions of roughly 530,000 gas-powered cars on the road each year.
• Metered-dose inhalers were the most environmentally harmful, accounting for 98 percent of emissions over the ten-year period from 2014 to 2024.
• Hydrofluoroalkane (HFA) propellants in metered-dose inhalers are potent greenhouse gases responsible for the high emissions.
• Researchers found that dry inhalers and soft powder mist inhalers are less harmful to the environment as they deliver medication to the lungs without the need for propellants.
• The study was conducted using a comprehensive U.S. database capturing inhaler prescriptions at the National Drug Code (NDC) level.
• Researchers plan to expand their research to examine inhaler-related emissions in specific patient populations, such as the Medicaid population, and compare clinical outcomes between lower- and higher-emission inhalers.

Statistics:

• Over 2 million metric tons of carbon emissions annually generated by inhalers in the United States from 2014 to 2024.
• Metered-dose inhalers accounted for 98 percent of emissions over the ten-year period.
• Hydrofluoroalkane (HFA) propellants in metered-dose inhalers are responsible for the high emissions.
• The study analyzed emissions from over 10 years of inhaler prescriptions in the United States.

Sources:

• UCLA Health study - publication in JAMA
• National Drug Code (NDC) database
• Environmental Protection Agency (EPA) reports on greenhouse gases
• American Lung Association - reports on asthma and COPD treatment
• New Reporter - provided news article on October 20, 2025, with information from Global Warming Focus.