Each use of a metered dose respiratory inhaler [MDI] emits some propellant. The amount is tiny, but a typical MDI propellant is a refrigerant gas with a huge global warming potential. Some are thousands of times stronger than CO₂. One news item implies that every 230 inhalers recycled are as good for the climate as avoiding an average year of driving an average car.

Moves are being made to substitute with less potent refrigerants and with dry powder inhalers [DPI] where possible. However, in healthcare, clinical outcomes must determine what’s best. For some conditions DPI have been shown to produce better outcomes but for others MDI are clearly the best option and we must live with them.

After use, the propellant is at extreme risk of escape if an unwanted inhaler is discarded into general waste, whether the treatment is discontinued or the inhaler is empty. In reality “empty” involves some unused propellant.

Recycle Now’s web page on inhalers says they can be handed in to any UK pharmacy for recycling. If someone you know uses an inhaler, find out whether they knew that fact (and indeed knew Recycle Now!); same for their household. What does the patient information that comes with the inhaler say about the propellant problem and its repair?

That’s OK then, what could possibly go wrong? We all know. Anywhere along the path from user to recycling facility there can be forgetfulness, ignorance, bad training, bad storage, accidents and so on.

If you have any knowhow on further reducing greenhouse gas emissions from MDIs, especially things a community could do, please post a comment on this page.