Materials

Tyre wear contaminating oceans with microplastics

Tyre particles could be an unreported source of microplastics transported to the oceans, according to a new report published yesterday (27 May).

An image of a tyre

The findings from a University of Plymouth study, funded by the Department for the Environment, Food and Rural Affairs (Defra), has found that tyre particles can be transported directly to the ocean through the atmosphere, or distributed by rainwater into rivers and sewers, where they can pass through the water treatment process.

Researchers estimate that around 100km2 of the UK’s river network – and more than 50km2 of estuarine and coastal waters – are at risk of contamination by tyre particles.

Evidence also highlights how synthetic fibres from clothing and maritime gear can infiltrate the ocean. The study underlines areas of intervention, such as changes to roadside drainage or making fabric designs which reduce fibre loss in the atmosphere.

Commenting on the results of the research, Rebecca Pow, Defra’s Minister responsible for the domestic marine environment 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 who directed the study said: “Scientists have long suspected that tyre debris is posing a hidden threat to the marine environment. However, there have been few studies measuring abundance in aquatic environments.

“Now we have a clearer indication on quantities we need to gain a better understanding on transport in the environment and the potential impacts on marine life. This study gives us a real insight into the importance of tyre wear as a source of microplastics.”

The fight to tackle microplastic pollution

Last year, Resource talked to marine litter expert Thompson about how microplastics have infiltrated the natural environment. 

There are three potential ways microplastics can cause harm, Thompson explained: physical disruption caused by accumulation; chemical transfer from chemicals included in the plastics, such as flame retardants; and chemical transfer from chemicals in the sea attaching to the microplastics. Although these ideas are yet to be proven, the scientific community has the impetus to prove them.

So far, the UK government has placed measures to curb the quantities of plastic entering marine environments.  This has included the 5p plastic bag charge - which has led to 15 billion fewer bags distributed – and the ban on microbeads in personal care products. Moreover,  Defra’s ban on plastic straws, stirrers and plastic-stemmed cotton buds will come into effect in October. The ban was planned for April but became delayed due to the potential problems the ban would entail for businesses during the Covid-19 pandemic.

In March, waste management company Viridor partnered with community interest company Nurdle to sponsor beach cleans. In one single beach clean, the group collected 25 million pieces of microplastic, sieving 2.1 tonnes of sand and removing 5,350,000 pieces of plastic. The data collected from the beach cleans was shared with the researchers at the University of Plymouth.

You can read more on the University of Plymouth’s study on Defra’s website.