Disposal practices for unwanted medicines in New Zealand community pharmacies and their willingness to support a low-carbon return scheme for metered-dose inhalers

Abstract In New Zealand, appropriate disposal of non-cytotoxic medicines involves collection, steam sterilisation and transfer to a dedicated landfill by a third-party contractor. However, little is known about whether community pharmacies routinely dispose of unwanted medicines via this process. Even when disposed of appropriately, medicines can still cause environmental harm. Pressurised metered-dose inhalers (pMDIs) pose a particular threat due to their hydrofluorocarbon (HFC) propellant gases, which remain after all doses have been used. A specialised scheme that safely captures and destroys HFCs in empty and unwanted pMDIs could significantly lower the carbon footprint of pMDI use. This study explored current pharmacy disposal practices for returned or expired medicines and the willingness of community pharmacies to participate in a dedicated pMDI return scheme. An invitation to complete an online questionnaire was emailed to community pharmacies across New Zealand. Questions examined current medicine disposal practices, willingness to be involved in a pMDI return scheme, and perceived enablers and barriers to involvement. Of the 1043 pharmacies invited to participate, 102 responses were sufficiently complete for analysis. Of these, 98% reported collecting unwanted or expired medicines for disposal. Current disposal methods included placing waste into dedicated pharmaceutical waste bins, pouring down the sink and placing with general rubbish. Regarding a pMDI return scheme, 42.7% expressed interest in participating, particularly if barriers such as the administrative burden and cost could be addressed. Increased education for pharmacy staff about pharmaceutical waste pathways and environmentally responsible disposal methods could support pharmacies to adopt practices more protective of planetary health. Graphical abstract Community pharmacies reported disposing of unwanted medicines via third-party contractors, down the sink or with general waste. Pharmacists reported feeling poorly informed about what happens to the waste when it leaves the pharmacy. A dedicated return scheme for pressurised metered-dose inhalers (pMDIs) could capture and destroy propellant gases.