Switching to ‘greener’ inhalers would result in large carbon savings alongside reduced drug costs, a new study has suggested.
Researchers at the University of Cambridge found that that the carbon footprint of metered-dose inhalers was between 10 to 37 times bigger than that of dry powder inhalers.
Metered-dose inhalers contain ‘potent greenhouse gases’ – hydrofluoroalkane propellants – that atomise the drug being delivered and pump it out users. They contribute an estimated 3.9% of the carbon footprint of the NHS in the UK.
There have previously been calls to switch to alternatives such as dry powder inhalers and aqueous mist inhalers, but the high ‘up-front’ cost of some dry powder inhalers has been a ‘significant barrier’, the study published by BMJ Open concluded.
However, it went on to suggest that swapping out one in ten metered-dose inhalers in England with the cheapest equivalent dry powder inhalers could leave to a reduction in drug costs of £8.2 million annually and reduce carbon dioxide equivalent emissions by 58 kilotonnes.
On an individual level, each metered-dose inhaler replaced by a dry powder inhaler would save between 150kg and 400kg a year, it said. This is a similar impact to installing wall insulation at home, recycling or reducing meat consumption.
‘Nurses have to be very careful’
Reacting to the research, respiratory nurse consultant Jane Scullion warned that an emphasis on ‘switching’ inhalers in the name of the environment may not be in the patients’ best interests, as metered-dose inhalers are vital to effective treatment.
‘If you’re going to switch, it has to be a face-to-face review,’ she told Nursing in Practice. ‘Nurses have to be very careful with the message they’re giving. It’s not that I am against looking after the environment, but we have to put it in context.’
She pointed out that under the European protocol the UK is under that aims to cut EU fluorinated gas emissions by two-thirds by 2030, medical devices are exempt.
‘My biggest concern at the end of the day is that it puts patient lives at risk,’ Ms Scullion continued. ‘On Twitter, I saw one person ask: “What’s the carbon footprint of me going in an emergency ambulance to hospital, dying there, and then me being cremated because I can’t use the inhaler?”
‘…If you look at the priorities, it’s about the right patient, right inhaler, right inspiratory flow rates in sickness and in health,’ she added, instead suggesting a focus on issues around recycling and packaging.
Dr Alexander Wilkinson, consultant in respiratory medicine from East and North Hertfordshire NHS Trust who worked on the study, emphasised that patients should not stop using their usual treatments.
He continued: ‘Instead we recommend patients review their condition and treatment at least annually with their healthcare professional and at this point discuss whether a more environmentally-friendly inhaler is available and appropriate in their situation.’
Dr James Smith, consultant in public health from the Department of Public Health and Primary Care at the University of Cambridge and who also worked on the study, said: ‘Climate change is a huge and present threat to health that will disproportionately impact the poorest and most vulnerable on the planet, including people with pre-existing lung disease.
‘Our study shows that switching to inhalers which are better for the environment could help individuals, and the NHS as a whole, reduce their impact on the climate significantly. This is an important step towards creating a zero carbon healthcare system fit for the 21st century.’
In 2017, seven out of ten inhalers prescribed in England were metered-dose inhalers, of the roughly 50 million prescribed.
According to the study authors, other actions people can take to reduce the carbon footprint of their inhalers include:
making sure they are using their inhaler correctly, as errors in technique are common;
returning used inhalers to pharmacies for proper disposal as metered dose inhalers have some propellant left in them when they are finished;
if their inhaler doesn’t have a dose counter, making sure they know how many doses it contains to avoid running out, or throwing away half-full inhalers.