Part of the Public Sector News Network

Air pollution from tyres up to 1,000 worse than from exhaust, claims study

Air pollution from car tyres can be up to 1,000 times worse than from an exhaust, research from Emissions Analytics has suggested.

Non-exhaust emissions (NEE) are expected to rise from 7.4% today to 10% of all UK PM2.5 emissions by 2030, in part due to increased regulations on exhaust emissions as well the further take-up of electric vehicles (EVs).

Last year, the Air Quality Expert Group (AQEG) raised the alarm and warned that urgent action must be taken to cut emissions from tyres and brakes.

To understand the scale of the problem, testing firm Emissions Analytics performed some initial tyre wear testing using a popular family hatchback running on brand new, correctly inflated tyres, which found that the car emitted 5.8 grams per kilometre of particles.

Compared with regulated exhaust emission limits of 4.5 milligrams per kilometre, the completely unregulated tyre wear emission is higher by a factor of over 1,000.

Emissions Analytics believes 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.

Read the study here.

Richard Lofthouse, senior researcher at Emissions Analytics said: ‘Its time to consider not just what comes out of a cars 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 cars 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.’

Responding to Emissions Analytics’ data, Mike Hawes, the Society of Motor Traders and Manufacturers (SMMT) chief executive called the study ‘irresponsible’.

He said: ‘Making sensationalist claims based on testing of a single-vehicle is not credible and, quite frankly, irresponsible.

‘Emissions from safety-critical brakes, tyres and road surfaces are very difficult to measure, and a challenge already taken seriously by the sector, governments and a UN global group, which are working together to better understand, and agree, how to test them in a scientific way.

‘Further, there is no evidence to suggest that electric vehicles have a propensity to emit more non-exhaust particulates than any other in fact, their regenerative braking systems mean wear is significantly reduced.’

The European Tyre and Rubber Manufacturers’ Association (ETRMA) welcomed Emissions Analytics study but said further studies are needed.

A spokesperson said: ‘Our analysis of the tyre wear rate results of EmissionsAnalytics driving test found that they do not reflect normal driving conditions and go far beyond the toughest realistic driving behaviour. The test conditions used a vehicle that was fully loaded with low-quality tyres. The test design incorporated high speeds and excessive cornering and underscores the unrealistic nature of the driving test and its results with an extreme driving behaviour.

‘The issue of tyre and road wear is complex and many factors influence the tyre tread abrasion rate. Driving behaviour, vehicle characteristics, tyre design, road topology and surface, traffic and weather can all impact particle generation.

‘EmissionsAnalytics results clearly show the impact of aggressive driving behaviour as well as carrying a load that is not representative of normal circumstances. Effective solutions therefore need to consider all external factors and are only possible if we work together with all relevant stakeholders.’

In January, a King’s College London study suggested that fine particulate matter (PM2.5) that originates from brake pads may be just as bad for the lungs as PM2.5 from diesel exhausts.

For the study, which was published in the journal Metallomics, researchers obtained dust from a brake pad testing factory which tests a broad range of vehicles used across Europe in real-time driving conditions.

Photo Credit – Pixabay

Notify of
1 Comment
Newest Most Voted
Inline Feedbacks
View all comments
Steven Woolrich
Steven Woolrich
2 months ago

Considering that a set of tyres lasts on average 40,000km I think the 5.8g figure might be a bit flawed. That would mean a set of tyres would shed 232kg of material during their lifetime, somewhat more than the weight of the whole set of tyres, let alone the tread.