Electric vehicles give a lesser-known pollution headache
As a car’s only point of contact with the road, tires do more work than they get credit for
Tires need to grip the road firmly enough for cars to accelerate, turn and brake without skidding, but they also need to reduce rolling resistance enough to maintain fuel efficiency.
For tire manufacturers, creating the perfect tire — one that balances performance and durability — is an unending task. In recent years, their work has been further complicated by electric vehicles (EVs).
Due to their bigger batteries, EVs tend to be significantly heavier than their internal combustion engine counterparts. Volkswagon’s e-Golf, for example, is about 400 kilograms heavier than the gas-powered Golf VII. That added weight rests on the car’s tires, so EVs need tires that are sturdier.
EVs also tend to have more torque than combustion engines, which their tires need to be able to transfer to the road within seconds.
Leading tire manufacturers are working on improving tire designs, and innovating new chemical formulas to meet the needs of EVs. Some brands have introduced products specifically for use on battery-run vehicles, whereas others say they have adapted all of their tires to perform better for both EVs and combustion engine vehicles.
“We have been optimizing our product range for a long time, especially in terms of service life, rolling resistance and rolling noise — factors that are of particular benefit to electric vehicles,” a spokesperson for tire maker Continental told DW in a statement.
How tires cause pollution
Considering the environmental impacts of cars, the focus tends to be on air pollution in the form of exhaust coming out of tailpipes. But tires contribute significantly.
Tires wear down over time — with every revolution, they shed tiny particles. The smallest of these pieces go into the air where they can be inhaled or drift off the road to settle on the soil nearby.
“Tire use is probably the naughtiest problem for vehicles,” Nick Molden, founder and CEO of Emissions Analytics, told DW. “With a lot of other pollution, you can effectively trap it using some sort of filter or catalyst. But the tire is a fundamentally open system — you cannot encase a tire.”
Emissions Analytics performs independent tests on cars including real-world tailpipe and tire emissions. It has compiled data that confirms that tire particulate pollution has significantly surpassed tailpipe emissions.
According to a report shared by Emissions Analytics, a single car sheds four kilograms (8.8 pounds) of tire particles weight per year, on average. Multiplied across the global fleet that equates to six million tons of tire particles annually.
“We measure the amount of solid material that comes out the tailpipe on the road, and we do the same measuring the mass that’s shed by the tires,” explained Molden. “Every year the amount coming from the tailpipe gets lower and lower, and the amount coming from tires is growing because vehicles are getting heavier.”
A case study published by Emissions Analytics compared the tire emissions from a Tesla Model Y to a Kia Niro and found that Tesla’s tire wear emissions were 26 percent greater.
Environmental hazard
Tire particulate pollution has two primary negative impacts on environmental health. The particulate itself washes into waterways and has been found to be a significant source of oceanic microplastics. Also, tires contain volatile organic compounds (VOCs), which are hazardous to human health, and react in the atmosphere to create smog.
A particularly concerning chemical in tires is 6PPD, which is used to prevent the rubber from cracking or breaking down. 6PPD is also water-soluble, so it is carried off of roads by rain and washed into rivers and oceans where it has been linked to mass salmon and trout die-offs.
Further studies found that 6PPD is absorbed by edible plants like lettuce and that the compound can be found in human urine.
“It’s the tire industry’s mission to secure a safe comfortable journey with peace of mind, and thus the addition of 6PPD to tire rubber is currently indispensable,” tire maker Bridgestone told DW.
Can tires’ pollution problem be solved?
Phasing out fossil fuel-powered vehicles is an urgently needed aspect of mitigating climate change. But if doing so comes with worsening tire emissions, that is also problematic.
“The obvious solution is to be driving and selling fewer cars,” climate activist Tadzio Müller told DW. He added, “The shift toward electric vehicles is meant to convince us that it’s going to save the planet, but of course, it cannot because the problem has always been capitalist growth.”
Asked if reducing car use overall is the best solution to tires’ environmental impacts, Molden told DW, “Yes, that would reduce tire emissions. But in terms of the lost economic activity, would that be worth it?”
“It’s better to create a market mechanism where it’s in the interest of the tire companies to invest a lot and come up with the best formulations,” Molden said, adding that currently there is a two to three times difference between certain tires in terms of VOC toxicity.
Molden said generally, Europe’s leading tire brands are among the best whereas cheap imports tend to be the worst.
On an individual level, avoiding rapid accelerations and immediate stops can reduce tire wear.
It’s also advisable to use tires to the end of their lifespan because new tires shed twice as much particulate during their first couple thousand kilometers.
See more here msn.com
Header image: Gabriel Nikias
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Howdy
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“the amount coming from tires is growing because vehicles are getting heavier.”
Hmmm. Tyre shedding is a perennial problem from any vehicle designed to shift weight, such as vans, heavy goods etc, I doubt the few EVs currently in use impacts that in any meaningfull way. In any case, untill the climate guff is taken seriously by motor manufacturers, and anybody else involved in this ‘nice little earner’ by fitting smaller power units, or reducing weight, removal of power draining ancillaries etc, it’s all nonsense. A light performance vehicle is going to burn rubber by design, and has been so for a long time. Again, singling out EVs is not an option. How many videos have you seen of burnouts?
“According to a report shared by Emissions Analytics, a single car sheds four kilograms (8.8 pounds) of tire particles weight per year, on average”
I do not see how average traffic can be calculated across the world – too many variables.
“Also, tires contain volatile organic compounds (VOCs), which are hazardous to human health”
Brake linings and the surfaces they bear against produce particulates, just look at any front wheel that sees duty. Isn’t this a problem?
The rubber boots and gaiters protecting steering racks, CV joints and such, where do you want to stop looking other than the obvious?
“Phasing out fossil fuel-powered vehicles is an urgently needed aspect of mitigating climate change. But if doing so comes with worsening tire emissions, that is also problematic”
A notion. Check out the devastation and real pollution created by electric vehicle production! Out of sight, out of mind.
“On an individual level, avoiding rapid accelerations and immediate stops can reduce tire wear.”
That’s allways been the case on any vehicle, even a pedal bike, but power on tap is the main EV selling point, It’s how you know they are toys for the rich, or easily lead. Nothing about them says efficiency.
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D. Boss
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I agree. And I go further to debunk most of this gibberish. First off a new car tire vs a completely bald one has a differential diameter of about 0.5 inches. And an average car tire diameter is about 28 inches, and it’s tread width 8 inches. Therefore the volume lost to tire wear over roughly 40,000 miles is 16 cubic inches. 16 cu in x 16.38cc/cu in = 262 cc. Tread rubber has a density of 1.25 g/cc so the total rubber lost when all of the tread has worn off is 238 grams, which is 0.72 pounds!
This over a several year span driving 40,000 miles. Average mileage per car in the US is 12,000/year. So all 4 tires only yields 0.75 lbs of rubber lost per year per car.
This idiotic article says cars loose 8.8 lbs of rubber per year!!! The tires weigh 15-25 lbs new depending on size, so let’s say average is 20 lbs. So these imbeciles are saying you can loose 11% of your tire’s weight in a year??? Or 44% of the tire weight by the time they are bald! Bull manure, and do not believe anything else they say based on this gross lie/falsehood/scam.
Furthermore they say some evil methyl ethyl bad stuff is added to rubber to prevent cracking, and they go on to say, straight faced, that this chemical is water soluble!!! (rolling on the floor laughing my ass off) Does anyone with half a brain believe any component of car tires is water soluble? Does that mean if you drive in the rain and this chemical is dissolved you tires will then crack? C’mon people….
I hold a patent for a novel method of recycling used tires and built both bench model and a pilot plant version of this system. I can assure you no part of tires are water soluble! And can assure you no rubber particles can become airborne for more than fractions of a second. (we deliberately rendered the rubber into fine rubber crumbs cryogenically to separate the desireable rubber from the steel and fiber belting and handling tons of this crumb per hour never required and airborne dust remediation.
Tire rubber is practically inert (though flammable), which is why it so difficult to recycle. That and it is infused with steel and fiber belting, and a thick set of hardened wires to form the bead….
Bottom line is this article is complete fabrication and hogwash. Bulk tires are a waste problem, but the tread left on roads – is minuscule compared to the asphalt roads themselves as pollutants. Or the millions of gallons of oil, transmission fluid, hydraulic fluid, and coolant which leaks from cars every day…. (including Teslas, which also have grease, oil, hydraulic fluid and yes coolant – they need coolants too)
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Boris Badenov
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I can tell you that my vehicle has only one tire that fits it and it is SOFT, if I’m really careful I might get 18,000 miles out of a set of 4. Beyond that, thank you for your numbers, it’s always been something I’ve wondered about.
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D. Boss
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Actually my numbers are exaggerated by about 2x. I was mad and in hast got two factors wrong. I computed the volume of the lost tread between new and bald as a solid, when in fact common tire tread has voids for wet traction. And the average thickness of that tread is not 1/2 inch but rather 3/8 inch.
I just checked as I am semi retired and work part time as an automotive repair tech to keep my body and mind exercised. Anyway, our shop changes tires and I compared new to nearly bald in several common tire sizes and the real number is closer to 0.35 lbs of tread lost over the lifetime of one common passenger car tire.
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Dave
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EVs,Unsafe at any speed 🔥🔥🔥
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