Microfibres can come from natural fabrics, such as cotton, or synthetic ones, such as polyester - which are also considered to be microplastics. Releasing microfibres into the environment is a concern because it can present potential health issues. The microfibres also adsorb and transport pollutants long distances and the fibres themselves can be irritants if they are ingested or inhaled.

Previous studies have shown that microfibres are released from clothes washers into laundry water, but this waste is treated, removing some or most of the fibres before the water is discharged into rivers or streams. However, to date, there has been very little information about whether tumble dryers, whose air passes through a duct and is vented directly to the outdoors, are an important atmospheric source of airborne microfibres and microplastic contamination in nature.

Kai Zhang, Kenneth Leung, and colleagues from the American Chemical Society (ACS) wanted to count...

Robert Heaton