And yet it remains unregulated.

When it comes to pollution from cars, a lot of the focus is on exhaust emissions. We're already seeing a dramatic switch to electric and other alternative forms of propulsion as bans on the sale of gasoline and diesel cars draw ever-closer, but what about the pollution from tires?

It's not something really ever talked about, but according to new research from Emissions Analytics, pollution from tire wear could be as much as 1,000 times worse than pollution from exhaust emissions.

The harmful particle matter from tires is a growing environmental concern, and with more and more larger and heavier vehicles like SUVs taking to the roads, the problem is only getting worse. Heavier electric vehicles are also contributing to the issue.

Unusually, unlike exhaust emission regulations, tire wear pollution isn't regulated whatsoever. Exhaust emissions are so strictly governed that cars these days tend to emit very little particulate matter, but the same can't be said for tires, or even brakes which pose a similar issue.

The regulated exhaust emission limit is 4.5 milligrams per kilometer, but tire wear "'emissions" could be as much as 1,000 times that, with rough roads, under-inflated tires, and budget tires causing the biggest issues.

"It’s time to consider not just what comes out of a car’s exhaust pipe but particle pollution from tire and brake wear," said Richard Lofthouse, Senior Researcher at Emissions Analytics. "Our initial tests reveal that there can be a shocking amount of particle pollution from tires – 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, tire 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."

Nick Molden, CEO of Emissions Analytics added: "The challenge to the industry and regulators is an almost complete black hole of consumer information, undone by frankly out of date regulations still preoccupied with exhaust emissions. In the short term, fitting higher quality tires is one way to reduce these NEEs and to always have tires inflated to the correct level.

"Ultimately, though, the car industry may have to find ways to reduce vehicle weight too. What is without doubt on the horizon is much-needed regulation to combat this problem. Whether that leads to specific types of low emission, harder wearing tires is not for us to say – but change has to come."

Source: Emissions Analytics
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POLLUTION FROM TYRE WEAR 1,000 TIMES WORSE THAN EXHAUST EMISSIONS

  • ight regulation of exhaust emissions by the EU has meant that new cars emit very little particle pollution
  • But tyre wear pollution is unregulated and can be 1,000 times worse, finds independent real-world testing experts Emissions Analytics
  • Increased popularity of SUVs, larger and heavier than standard vehicles, exacerbates this problem – as does growing sales of heavy EVs and widespread use of budget tyres
  • Fitting only high-quality tyres and lowering vehicle weight are routes to reducing these ‘non-exhaust emissions’
  • Learn more about Emissions Analytics here: https://www.emissionsanalytics.com

Oxford, 6th March 2020:  Pollution from tyre wear can be 1,000 times worse than what comes out of a car’s exhaust, Emissions Analytics has found.

Harmful particle matter from tyres – and also brakes – is a very serious and growing environmental problem, one that is being exacerbated by the increasing popularity of large, heavy vehicles such as SUVs, and growing demand for electric vehicles, which are heavier than standard cars because of their batteries.

What’s more, vehicle tyre wear pollution is completely unregulated, unlike exhaust emissions which have been rapidly reduced by car makers thanks to the pressure placed on them by European emissions standards. New cars now emit very little in the way of particulate matter but there is growing concern around ‘non-exhaust emissions’.

Non-exhaust emissions (NEE) are particles released into the air from brake wear, tyre wear, road surface wear and resuspension of road dust during on-road vehicle usage. No legislation is in place to limit or reduce NEE, but they cause a great deal of concern for air quality.

NEEs are currently believed to constitute the majority of primary particulate matter from road transport, 60 percent of PM2.5 and 73 percent of PM10 – and in its 2019 report ‘Non-Exhaust Emissions from Road Traffic’ by the UK Government’s Air Quality Expert Group (AQEG), it recommended that NEE are immediately recognised as a source of ambient concentrations of airborne particulate matter, even for vehicles with zero exhaust emissions of particles – such as EVs.

To understand the scale of the problem, Emissions Analytics – the leading independent global testing and data specialist for the scientific measurement of real-world emissions – performed some initial tyre wear testing. Using a popular family hatchback running on brand new, correctly inflated tyres, we found that the car emitted 5.8 grams per kilometer of particles.

Compared with regulated exhaust emission limits of 4.5 milligrams per kilometer, the completely unregulated tyre wear emission is higher by a factor of over 1,000. Emissions Analytics notes that this could be even higher if the vehicle had tyres which were underinflated, or the road surfaces used for the test were rougher, or the tyres used were from a budget range – all very recognisable scenarios in ‘real world’ motoring.

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.”

Nick Molden, CEO of Emissions Analytics said: “The challenge to the industry and regulators is an almost complete black hole of consumer information, undone by frankly out of date regulations still preoccupied with exhaust emissions. In the short term, fitting higher quality tyres is one way to reduce these NEEs and to always have tyres inflated to the correct level.

“Ultimately, though, the car industry may have to find ways to reduce vehicle weight too. What is without doubt on the horizon is much-needed regulation to combat this problem. Whether that leads to specific types of low emission, harder wearing tyres is not for us to say – but change has to come.”