Tire makers under pressure because too much rubber is getting on the road

Tire makers under pressure because too much rubber is getting on the road


By Nick Carey and Barbara Lewis

LONDON (Reuters) – Tire makers are under pressure to almost literally reinvent the wheel as regulators turn their attention to tire pollution that will increase with the rise of electric vehicles (EVs) and threaten to undermine those cars’ green credentials .

When tires make contact with the road, small particles are abraded and expelled. The added weight of EVs coupled to their batteries means this little-discussed form of pollution – from an estimated 2 billion tires produced worldwide each year – is becoming a bigger problem.

Major manufacturers, including Goodyear, Bridgestone, Michelin and Continental, are also trying to fend off competition from cheaper Chinese rivals.

“It’s not quite a perfect storm,” said Gunnlaugur “G” Erlendsson, CEO of UK-based startup Enso, which has developed more sustainable tires specifically for electric cars and rents out tires it takes back to use at end-of-life. to recycle. “But it’s close.”

Tire makers are racing to get ahead of emissions regulations and find alternatives.

Emerging research shows the toxicity of tires, which contain an average of about 200 components and chemicals, often derived from crude oil.

While critics say tires contain many toxic and cancer-causing chemicals, so far there is only really consensus on one – 6PPD, an antioxidant and antiozonant found in all tires that reduces cracking.

This year, California is expected to be the first authority to require tire manufacturers to demonstrate that they are seeking an alternative to 6PPD – a degraded form that is deadly to some fish and has been found in human urine in southern China.

The European Union’s upcoming Euro 7 emission regulations will set standards for tires for the first time.

To complement these challenges, manufacturers will need to develop lower-emission tires for heavy-duty EVs, which Michelin and Goodyear have reported can wear tires up to 50% faster.

“The unintended consequence of electric cars is that unless we have better tires we will have more tire pollution,” said Erlendsson of Enso, whose tires emitted 35% less in testing than premium EV tires from major manufacturers.

He says this is because their reliance on more expensive, higher quality materials makes them more durable.

Bridgestone and Goodyear declined to discuss the industry’s emissions challenges.

But Michelin, Continental and Pirelli told Reuters they are pursuing alternatives to 6PPD, with Michelin and Continental adding that collective industry action may be needed to find solutions.

Asked about the Euro 7 regulations, Michelin said it wants global standards to push higher-emission tires, which are usually cheaper, out of the market. Continental advocates a global wear standard with transparent labeling for consumers.

Nick Molden, CEO of UK-based testing specialist Emissions Analytics, said the “dirty end” of the list of tires the company has tested are “cheap Chinese imports” common in the European market.

The Chinese manufacturers of Rockblade, Mazzini and Ovation – one of the worst-performing tire brands on Molden’s list – did not respond to requests for comment.


Data provided to Reuters by Emissions Analytics shows that new tires developed so far are unlikely to solve the problem.

For example, while tests conducted on Continental bicycle tires made with dandelions show a 24.5% drop in carcinogenic aromatics — which help cars track the road — the chemicals in the particles they emit are generally equally toxic, Molden said .

“They’re just different bad,” he added.

Continental said its dandelion tires were developed to source a sustainable form of natural rubber, and tackling 6PPD was a separate focus.

“It is our responsibility to take care of this and find a solution” for 6PPD, said Thomas Kramer, head of material wear at Continental.

Research developed during the Korean War shows that when 6PPD reacts with oxygen or ozone, it forms 6PPD quinone, which is responsible for the mass die-off of Coho salmon off the west coast of the US.

California regulators say the impact of 6PPD on human health is unclear, but are finalizing documents that could require tire manufacturers to analyze safer alternatives.

The tire industry said it is difficult to find a replacement for 6PPD because any new chemical must prevent tires from deteriorating and bursting without affecting other properties.

“Tires are a compromise” between safety, noise, handling and wear, said Adam McCarthy, secretary general of the European Tire and Rubber Manufacturing Association.

Enso’s CEO Erlendsson said the industry could have a solution in the market within five years if pressured, but at a price.


Shifting focus from tailpipe emissions, EU and UN regulators are working on Euro 7 regulations to limit emissions from brakes and tires. EU lawmakers say they could agree as early as next year.

Tire particles are expected to be the largest source of microplastics potentially harmful to aquatic life by 2050, according to data prepared for the European Commission.

Michelin estimates that worldwide tires emit about 3 million tons of particulate matter annually — creating another 3 million tons of particulate matter from the road surface, said Cyrille Roget, director of technical and scientific communications.

Michelin’s tests show that if you drive 200,000 kilometers (124,274 miles) per year on its tires, you emit about 1.5 kg (3.3 lb) of particulate matter, compared to a market average of 3.6 kg, Roget said.

The worst-performing rival tires tested by Michelin to date emit around 8kg per year.

If Euro 7 were used to stop the sale of the highest-emission tires, “you would already take a lot of particles off the market,” Roget said. “That’s the first step and it’s something we think can be done faster.”

Michelin and Continental said they are already focused on making their tires more sustainable — Michelin cut tire emissions by 5% between 2015 and 2020, Roget said.

But Emissions Analytics’ Molden said the shift to EVs means tire makers will be forced to develop more sustainable tires – a tough challenge without natural rubber, which would be difficult to develop sustainably enough to support the entire industry.

As part of its efforts to be as sustainable as possible, Enso has a recycling deal with Norwegian company Wastefront.

“The arrival of the electric car is the time to make this change, to improve tires,” said Enso’s Erlendsson. “We will never end up with zero tire pollution, but we can reduce it.”

(Reporting by Nick Carey and Barbara Lewis, editing by Ben Klayman and Catherine Evans)