A major government-funded research study suggests particles released from vehicle tyres could be a significant and previously largely unrecorded source of microplastics in the marine environment.
The study shows that tyre particles can be transported directly to the ocean through the atmosphere or carried by rainwater into rivers and sewers, where they can pass through the water treatment process.
Researchers estimate this could place around 100million m² of the UK’s river network – and more than 50million m² of estuarine and coastal waters – at risk of contamination by tyre particles.
The study is one of the first worldwide to identify tyre particles as a major and additional source of microplastics.
Scientists have previously discovered microplastics, originating from microbeads in cosmetics and the degradation of larger items such as carrier bags and plastic bottles, in marine environments globally – from the deep seas to the Arctic.
Following the government’s ban on rinse-off microbeads, which is one of the toughest in the world, the Defra-funded study led by the University of Plymouth now reveals vital new information to improve scientific understanding of how tiny particles from tyres, synthetic fibres from clothing and maritime gear also enter the ocean.
Domestic Marine Minister Rebecca Pow said: “Reducing plastic pollution in the ocean is one of the greatest environmental challenges that we face.
“This study will help us face that challenge by identifying areas for future research, such as changes to roadside drainage and textile design.”
Professor Richard Thompson OBE, head of the International Marine Litter Research Unit directed the study and said scientists had long suspected that tyre debris posed a hidden threat to the marine environment.
He added: “This study gives us a real insight into the importance of tyre wear as a source of microplastics.
“However there are still many unknowns, and compared with other forms of microplastics we know relatively little about tyre wear particles.
“So it is important to continue to take steps to reduce emissions of better understood sources like fibres from textiles and the fragmentation of larger items.”