Global access and patient safety in the transition to environmentally friendly respiratory inhalers: the Global Initiative for Asthma perspective.

Climate change and its impacts on the health of our planet and its people are, deservedly, on centre stage in international discourse, and have prompted critical evaluation of all human activities that could lessen the degree and progression of these effects. Health care, too, is under scrutiny for its contribution to climate change. Among the many issues is the global warming potential of gases in medical devices, including fluorinated gas propellants in pressurised metered-dose inhalers (pMDIs) that are often used for the treatment of airway diseases; these contribute a small but substantial proportion of global greenhouse gas emissions (estimated as <0 center dot 1%). 1-9 Many countries, including the USA, the UK, and several in mainland Europe, have developed policies to reduce the carbon footprint of inhalers. The chief measures proposed are to replace harmful propellants, such as hydrofluoroalkane-134a and hydrofluoroalkane-227ea,1,2 with safer alternatives that are under development; 4,10,11 in the meantime to choose pMDIs that have lower fluorinated gas content;12 and to encourage a switch to dry-powder inhalers (DPIs), which do not contain propellants (assuming that the patient can use the relevant inhaler correctly).12,13 At the same time, international action is being taken to limit use of perfluoroalkyl and polyfluoroalkyl substances (PFAS),14 a large and diverse group of chemicals that are widely used in consumer products and industry, and some of which have significant toxicity and accumulate in the environment over time. Actions to limit PFAS, if worded too broadly, could affect supply of some new propellants that have low global warming potential and no evidence of toxicity or accumulation over time.