New research by Empa has highlighted how microrubbers are transported into water supplies and the effect it has on the body and the environment.
There is growing concern and research on microplastics, which pollute our air, water and even snow. However, there is little research on the effects of microrubber on the planet and the body. The fine particles from tyre abrasions enter our soil and air via the road’s surface.
A team of researchers belonging to Empa, a material science institute in Switzerland, have now calculated that over the last 30 years around 200,000 tonnes of microrubber has accumulated in the Swiss environment.
Professor Bernd Nowack from Empa’s Technology and Society laboratory identified car and truck tyres to be the main source of microrubber. “We quantified the abrasion of tires, but also the removal of artificial green areas such as artificial turf,” says Nowack.
This only plays a subordinate role as only 3% of the rubber particles emitted come from rubber granulate from artificial green areas. Tire abrasion is responsible for the remaining 97% of micro-rubbers.
Of the particles released into the environment, almost three quarters remain within 5 metres of the road’s surface. 5% stays in the nearby soil and a further 20% is polluting bodies of water. The research team’s calculations are based on data on the import and export of tyres and then modelled on the behaviour of rubber on roads and in road wastewater.
Since the year 2000, the guidelines for recycling water and the prevention of soil pollution have been tightened significantly. Through measures such as the construction of road wastewater treatment plants, part of the microrubber can be removed from the water.
Part of the microrubber is first transported by air into the first 5 metres at either side of the road, there it can be deposited into the soil or it can be whirled around again. “The proportion of tyre abrasion in inhaled fine dust is also in the low single-digit percentage range at locations close to traffic,” says Christoph Hüglin from Empa.