Vape mouthpieces could be swarming with fungi that harm airways

Fungal species, one of which caused chronic bronchitis in mice, were collected from the mouthpieces of e-cigarettes used by daily vapers

By James Woodford

13 August 2025

Vaping is a healthier option than smoking, but it still isn’t risk-free

Matthew Horwood/Getty Images

An array of fungi, some of which have been linked to lung complications, have been collected from e-cigarette mouthpieces.

The use of vapes is generally recommended as a way to transition away from smoking, but their long-term health impacts are poorly understood.

Read more

How bad is vaping for your health? We’re finally getting answers

In vapes, a battery-powered coil heats a liquid that typically contains nicotine, producing vapour that is inhaled by users. Health concerns have largely centred on the toxicity of the liquid’s chemical constituents, so no one has tried to understand which microbes may make their way from the devices into users’ airways.

To learn more, Borna Mehrad and his colleagues at the University of Florida recruited 25 people who used disposable vapes every day. The researchers cultured the microbes from the mouthpieces of their devices, comparing them to those in the volunteers’ mouths.

Only a small number of the vapes contained bacteria. But according to the researchers, more than half were “abundantly colonized” with fungi species that were distinct from those in the volunteers’ mouths – and 80 per cent of them are capable of causing ill health in people.