Inhalers emit as much CO2 as half a million cars

Technology Oct 07, 2025

A new study shows that the metered-dose inhalers (MDIs) many people use for asthma or COPD are surprisingly big polluters—making up nearly all emissions from inhalers in the US, about as much CO2 each year as over half a million cars.

Alternatives like dry-powder inhalers have smaller carbon footprint

Most of these emissions come from "rescue" inhalers, which use powerful greenhouse gasses called HFA propellants.
While alternatives like dry-powder inhalers have a much smaller carbon footprint, switching isn't always easy in the US due to cost and insurance hurdles.
Countries like Sweden and England have promoted or increased the use of alternative inhalers without any loss in health outcomes, showing it's possible to breathe easier for both people and the planet.