News: Why tires — not tailpipes — are spewing more pollution from your cars

[Arcadia]

study link https://pubmed.ncbi.nlm.nih.gov/36435278/

news link
https://www.washingtonpost.com/climate-environment/2023/07/09/tire-brake-tailpipes-emissions-pollution-cars/?fbclid=IwAR2Gm1BUN2YyE7jGaIejlYW1O5j4UcPXKYVCbP2H4JbYOZtbtUghdQka3vU_aem_Ab50EHTgVjeTyCwkS2USpJ7Y-1J2cyiBVXqaC5dZd6U8pkrAfUZZq7yT6w_JW77025o
““These non-tailpipe emissions are becoming an issue for two reasons,” said Heejung Jung, a professor at the University of California, Riverside. “One, it hasn’t been regulated. Second, its chemical composition can be potentially more toxic, especially for brakes’ [particulate matter] … they’re all metallic.”

In California, sources other than tailpipes are the dominating source of traffic emissions. A lot of pollution comes from road dust, kicked up from cars driving along the road. In recent years, particulate emissions from brakes and tires are starting to grow as well, even outweighing those from tailpipes in some locations.

In one study, Jung and his colleagues looked at car emission sources along two highways in Long Beach and Anaheim in January and February 2020. In Anaheim, they found brake and tires constituted 30 percent of PM 2.5, whereas exhaust emissions linked to gasoline and diesel constituted 19 percent. In Long Beach, brake and tires constituted 15 percent of PM 2.5 pollution, which was the same as pollution from gas and diesel.

The team’s findings match with emission predictions by the California Air Resources Board, a state government agency that aims to reduce air pollution and that funded the emissions research. The agency predicted PM 2.5 pollution from brakes would be greater than exhaust pollution around 2020, given additional cars and cleaner exhaust policies.

But these emission patterns aren’t specific to California. Jung said tailpipe emissions have declined in all 50 states, a result of policies from the Environmental Protection Agency. But “in all 50 states, brake and tire emissions are not regulated, so we will see the same thing in other states.”

The pollution from your brakes and tires isn’t benign, either. Tests by Emissions Analytics, an engineering consulting company based in England, found tires produce about 2,000 times more particle pollution by mass than tailpipes. Although not regulated, those emissions exceed the legal particle limits for exhaust. The emissions also consisted of more than 400 compounds of different sizes and toxicity.

“Traditionally, it’s been assumed that it’s been big chunks of rubber breaking off tires and it’s just captured in the drains and it’s not a big problem,” said Nick Molden, founder and CEO of Emissions Analytics. “What we’ve shown from our testing is that it’s a mixture of bigger particles, but also ultrafine particles.”

Molden says they found particles as small as six nanometers, which can be inhaled. The tires also emit carcinogens. Other studies found metals. He said “water is likely to be the single biggest destinations of these particles” as materials get washed into drains from the road or seep through soil.

While it’s known that these chemicals and elements can have grave effects on humans, Molden said there’s a gap in knowledge of how many and at what concentrations these compounds end up in humans and animals. Research shows a particular chemical found in tires has been linked to declines in salmon in California, but that could just be the start. “It actually could be more in humans and animals than we thought. We just we don’t quite know yet,” he said.

That’s why it’s important to have a good car air filter as well, Molden said.

The issue will only become more pressing as heavier electric vehicles are introduced. Jung said large electric vehicles, due to their large batteries, are at least 50 percent heavier than an internal combustion engine-powered vehicle and will put more wear on tires and cause more pollution.

The solution isn’t to get rid of tires or electric cars, but perhaps shift the materials of the tires to natural or non-fossil fuel sources, the scientists said. For instance, many tires are made of synthetic rubber derived from crude oil, which includes carcinogens.“

[KSera]

Tires are gross. I’d love to see better materials emerge for making them that isn’t so toxic. That’s an interesting study and piece. I do want to point out there’s an apples to oranges going on in this comparison. Tires and brakes produce polluting particles that are worth reducing/eliminating. This is completely unrelated though to the climate change inducing impacts of tail pipe omissions. I’m afraid readers are going to conflate “pollution” with “climate change” and think that it’s the tires that are responsible, and it’s not. Pollution is bad and something we want to address, while climate change is an out and out emergency that is already, and will continue to change life as we know it and particularly for our children. The article is a bit of a hit piece trying to change the subject regarding tailpipe omissions and electric vehicles. Those things are unrelated to brake and tire pollution.  (And our neighbor’s large gas fueled pickup is heavier than our EV, fwiw.)

[Faith-manor]

2 hours ago, KSera said:

Tires are gross. I’d love to see better materials emerge for making them that isn’t so toxic. That’s an interesting study and piece. I do want to point out there’s an apples to oranges going on in this comparison. Tires and brakes produce polluting particles that are worth reducing/eliminating. This is completely unrelated though to the climate change inducing impacts of tail pipe omissions. I’m afraid readers are going to conflate “pollution” with “climate change” and think that it’s the tires that are responsible, and it’s not. Pollution is bad and something we want to address, while climate change is an out and out emergency that is already, and will continue to change life as we know it and particularly for our children. The article is a bit of a hit piece trying to change the subject regarding tailpipe omissions and electric vehicles. Those things are unrelated to brake and tire pollution.  (And our neighbor’s large gas fueled pickup is heavier than our EV, fwiw.)

Agreed.

Also, the heavier the vehicle, the faster they burn through tires and brakes because of the mass, and longer, harder braking is required to come to a stop. Strict regulation of heavy vehicles could really reduce pollution. It won't help climate change at this tike, but we can and should improve air quality. Where I live 1/3 of the vehicles on the roads are heavy pick up trucks for pleasure use and commuting, not for businesses. I have no problem with my local farmer owning a truck and grabbing his feed and whatever with it. I have huge problems with all the people who give their teenagers a pick up truck for high school graduation. Not to mention the gas mileage is crap, and that is a huge problem.

[KSera]

36 minutes ago, Faith-manor said:

Strict regulation of heavy vehicles could really reduce pollution. It won't help climate change at this tike, but we can and should improve air quality.

We’d have to make sure it wasn’t written such to preference gas powered vehicles over EV. Because decreasing ICE vehicle usage and increasing EV usage is something that will help climate change. 

[Faith-manor]

1 minute ago, KSera said:

We’d have to make sure it wasn’t written such to preference gas powered vehicles over EV. Because decreasing ICE vehicle usage and increasing EV usage is something that will help climate change. 

For sure. 

[vonfirmath]

1 hour ago, Faith-manor said:

Agreed.

Also, the heavier the vehicle, the faster they burn through tires and brakes because of the mass, and longer, harder braking is required to come to a stop. Strict regulation of heavy vehicles could really reduce pollution. It won't help climate change at this tike, but we can and should improve air quality. Where I live 1/3 of the vehicles on the roads are heavy pick up trucks for pleasure use and commuting, not for businesses. I have no problem with my local farmer owning a truck and grabbing his feed and whatever with it. I have huge problems with all the people who give their teenagers a pick up truck for high school graduation. Not to mention the gas mileage is crap, and that is a huge problem.

Sometimes it is hard to see all the uses of a pick up trucks. Few people can afford to have a pick up truck that is used ONLY for the times it is strictly necessary. But that pickup truck is being used to tow a camper at least one weekend a month. Or to connect a trailer and help a troop go camping multiple times a year.  Etc.  I know with our CRV, I can only carry 3 people and go camping (AND I can't take the troop goods if I've got 3 people in the car). But thankfully we've got a truck in the troop that helps handle more storage needs when needed.  Another guy with a troop cleans up the church grounds every other weekend and hauls off the trash.  Plus we borrow it for our Christmas parade when we have a float.  Etc.