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Farm-bound sludge teems with tiny plastic fibres


An astonishing 700,000 microfibres – threads of plastic the size of an ant’s leg – leach out of an average 6kg wash of acrylic clothing. And research by Brunel University London shows this plastic pollution has travelled at least as far as Britain’s farms.

The team behind BBC’s Countryfile, one of the nation’s most popular TV programmes, turned to Brunel ecotoxicologist Dr Chris Green to investigate whether microplastics – microfibres and other small plastic pieces – are present in biosolids: sludge from waste water treatment that’s been pasteurised so it can be spread onto farmland as a fertiliser and soil improver.

Although plastic microbeads used in cosmetics have made the headlines in recent years, microfibres may be a more significant but poorly understood part of the microplastics problem. With our laundry’s waste water discharged into the sewage system, it’s important to track where this domestic pollution ends up.

In the episode aired on Sunday 21 May, Countryfile reporter Tom Heap joined Dr Green for a demonstration of a simple technique that separated microplastics from the organic material in biosolids – and then confirmed that they were indeed plastic with the help of Brunel’s Experimental Techniques Centre.


UK viewers can watch the episode of Countryfile on BBC iPlayer. The sequence starts at 26:34. 

Observing the evidence under the microscope, Tom Heap couldn’t believe how tiny the fragments were. He later added: “Microplastics in the ocean are a concern for marine biologists and, increasingly, for environmental groups. But the discovery that microplastics are on our land brings this much closer to home.”

The laboratory sequence used by Dr Green, a post-doctoral research fellow in Brunel’s Institute of Environment, Health and Societies, was funded and set up by the Plastic Oceans Foundation, which is at the forefront of thinking about plastics in the environment.

Jo Ruxton, UK CEO of the Plastic Oceans Foundation, commented: “The presence of so many microfibres in the biosolids sample is both shocking and sadly not surprising.

“Prevention is always better than cure, so the Plastic Oceans Foundation is working to stop this plastic being released into the environment wherever possible, right back to the source of the pollution.

“We’re asking washing machines manufacturers to prevent microfibres being washed away into our rivers, and synthetic clothing manufacturers need to improve their fabrics. Ultimately, we aim to influence business and governments on the actions they need to take to protect the environment.

“But as long as microfibres are released into the environment, we need better understanding of the effect they have – hence our invaluable working relationship with Brunel.”

Dr Green added: “We don’t yet know the significance of microplastics in biosolids for land-based ecosystems. Given that their presence is likely to be widespread, the next step is to investigate further in collaboration with the UK water industry.

“By improving our understanding of what types of plastics are in biosolids, we may be able to better understand their sources and how to best reduce their numbers.”


Source of statistic: Napper, I.E. and Thompson, R.C. (2016) ‘Release of synthetic microplastic plastic fibres from domestic washing machines: Effects of fabric type and washing conditions’, Marine Pollution Bulletin, 112(1–2), pp. 39–45.

Read more about the Plastic Oceans Foundation (including their celebrated and thought-provoking documentary A Plastic Ocean) and Brunel University London’s Institute for Environment, Health and Societies.

Reported by:

Joe Buchanunn, Media Relations