A puff helps patients but hurts the environment

People living with asthma are most vulnerable when taking a breath of air, yet their use of widely prescribed inhalers to help them breathe better contributes to the worsening of air quality.

- Judith Tan Correspondent

Doctors say asthma patients should be managing their conditions better instead of turning to the inhalers frequently for treatment, to prevent more damage to the environment.

Scientists from SingHealth Polyclinics (SHP) have found that these inhalers generate a significant amount of greenhouse gases.

"These are the L-shaped metered-dose inhalers that release small puffs to help ease breathing for patients with asthma. But they emit high levels of hydrofluorocarbon (HFC) propellants. The puffs add up," said Clinical Associate Professor Tan Ngiap Chuan, director of research at SingHealth Polyclinics.

"What this means is that when you use (the inhalers) and when the chemicals are released, they trap the heat within the environment, causing the temperature to rise."

HFC propellant is a type of aerosol propellant that uses a synthetic gas that contains hydrogen, fluorine, and carbon in products like hairsprays, deodorants and some inhalers.

Prof Tan and his team conducted two studies to understand the environmental impact of the metered-dose inhalers and assess the effect of the newer therapies in terms of asthma control and environment footprint.

On average, each patient using metered-dose inhalers with propellants in 2023 produced 140kg of CO2 emissions (CO2e) over a year, their studies found.

Based on the studies, The Straits Times calculated that inhalers used by one patient over a year emitted as much greenhouse gas as the average petrol-powered car that has travelled 97km, or from the eastern end of Singapore to the western end and back.