Plastic pollution is a well-known problem. However, few have heard of micro rubber pollution.
Like micro plastic, micro rubber is largely invisible. From 1998 to 2018, researchers estimate that 200,000 tonnes of micro rubber, shed from vehicle tyres as they move along the road, has accumulated in the environment in Switzerland.
Bernd Nowack from Empa, a Swiss materials, science and technology research organisation, has identified vehicle tyres (97%) as the main source of this micro rubber pollution. The remaining 3% comes from artificial turf, which is often made from ground up tyres.
Micro rubber pollution dwarfs micro plastic pollution. According to Nowack’s calculations, only 7% of the polymer-based micro particles released into the environment are made of plastic. The other 93% come from tyre abrasion. “The amount of micro rubber in the environment is huge” says Nowack.
Almost three-quarters of road-based micro rubber pollution remains within 5 metres of the roadside, with the rest leaching into soil (5%) or finding its way into waterways (20%).
Because much of the pollution is confined to the roadside, measures such as the construction of road wastewater treatment plants to remove micro rubber from roadside water, can make a big difference.