Using fibre-catching devices in washing machines can dramatically reduce the amount of microscopic particles potentially entering the marine environment, researchers say.
A study conducted at the University of Plymouth compared six devices, ranging from prototypes to commercially available products.
The most successful reduced the amount of fibres released into waste water by almost 80%, the research found.
But researchers, writing in the journal Science Of The Total Environment, say such devices will only ever be part of any solution.
Dr Imogen Napper, from Plymouth University’s International Marine Litter Research Unit, said: “Fibres from clothing are among the key sources of microplastics, and companies are inventing ways which claim to reduce the amount of fibres which enter wastewater.
“We wanted to see how effective they were both in catching fibres, but also stopping clothes from shedding them in the first place.
“Our results show there is a huge variety between the devices available, with some significantly reducing the number of fibres released.”
A recent study by Plymouth University found wearing clothes releases as many microplastics as from washing them.
In May, a report produced for the Department for Environment, Food & Rural Affairs (Defra) suggested that fitting filters to washing machines could be less effective than changing fabric designs to reduce fibre loss.
For the latest research, which was funded by the National Geographic Society and Sky Ocean Rescue, scientists washed three different synthetic fabric types to represent a typical mixed load.
They used a mesh to capture fibres entering wastewater and measured the mass of particles generated without filters, with three in-drum devices and three external washing machine filters.
The most effective device, the XFiltra external filter, reduced the quantity of microfibres being released by 78%.
A washing bag by Fourth Element was the least effective device in the study, reducing microfibres by 21%, the study found.
Professor Richard Thompson, head of the International Marine Litter Research Unit, said: “Too often, the quest for fast fashion and market pressures means that appropriate environmental considerations are being sacrificed.
“If we are to achieve widespread and lasting change, it is essential for scientists to provide the independent evidence that demonstrates the scale of the problem as well as any potential solutions.
“Some of the devices we tested can undoubtedly reduce the fibres generated through the laundry process, but perhaps the most overarching change would be to design garments to last longer and shed less fibres in the first place.”
The study has been welcomed by the Marine Conservation Society, which recently launched its own Stop Ocean Threads campaign.
Dr Laura Foster, head of clean seas at the charity, said: “This independent research shows clearly that washing machine fitted filters are the most effective method of preventing microfibre loss from washing clothes.
“We’re urging people to sign our petition which will require the filters, by law, in all washing machines from 2024.
“Having all washing machines fitted with filters will make a huge impact on the volume of microfibres polluting our ocean from every wash.
“The clothes we have will continue to shed fibres now and in the many years to come, which means that we need to have filters fitted as well as improvements from the fashion industry.”