Pollution from tyre wear can be up to 1,000 times worse than the emissions produced from a car’s exhaust, claims a UK research group.
Particulate matter produced by tyres and brakes is harmful, and levels are increasing as a result of the growing number of large SUVs and even electric cars — which are heavier than standard cars and therefore put more pressure on their tyres – on city streets.
In addition, tyre wear pollution remains unregulated, so while tighter control on exhaust emissions means that the amount of particulate matter produced by combustion-engined vehicles has fallen, ‘non-exhaust emissions’ (NEE) have been allowed to continue. There is currently no legislation in place to limit or reduce NEE, either.
Non-exhaust emissions are believed to contribute to the majority of primary particulate matter produced by road transport, which was highlighted in a report by the government’s Air Quality Expert Group released in 2019. It recommended that NEEs be immediately recognised.
Emissions Analytics, therefore, undertook real-world testing to see the number of particulates produced by tyres. It found that a standard family hatchback using brand-new correctly-inflated tyres emitted 5.8 grams of particulates per kilometre.
In contrast, the regulated exhaust emission limit of 4.5 milligrams per kilometre show that unregulated tyre emissions are higher by a factor of over 1,000. Emissions Analytics believed that if the vehicle had been using under-inflated tyres or driving on a road with poorer surface quality then the tyre emissions could have been far higher.
Richard Lofthouse, senior researcher at Emissions Analytics said: “It’s time to consider not just what comes out of a car’s exhaust pipe but particle pollution from tyre and brake wear. Our initial tests reveal that there can be a shocking amount of particle pollution from tyres — 1,000 times worse than emissions from a car’s exhaust.
“What is even more frightening is that while exhaust emissions have been tightly regulated for many years, tyre wear is totally unregulated – and with the increasing growth in sales of heavier SUVs and battery-powered electric cars, non-exhaust emissions (NEE) are a very serious problem.”