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Comment by ipqk | Hacker News Reader

Sorry, but most car pollution is from the tires/tyres, not the exhaust. Electric cars don't solve that, and may even make it worse because they're heavier.

https://www.theguardian.com/environment/2022/jun/03/car-tyre...

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Your link does not say what you purport it to say. It limits things to particle pollution. It makes sense that tires will create more particle pollution, but gasoline creates a lot of gas pollution as well.

The tire & brake particulates go into the air. Sure, technically not gas, but we breathe it in just the same.

Straw man. You said “most car pollution is from the tires/tyres.” That is unsubstantiated by your source.

This is not some secret:

https://e360.yale.edu/features/tire-pollution-toxic-chemical....

Interesting. This article you linked states that tires emit not only more particulate emissions than tailpipes during driving, but also more VOC emissions!

> Another area of research centers on the impacts of aromatic hydrocarbons — including benzene and naphthalene — off-gassed by synthetic rubber or emitted when discarded tires are burned in incinerators for energy recovery. Even at low concentrations, these compounds are toxic to humans. They also react with sunlight to form ozone, or ground-level smog, which causes respiratory harm. “We have shown that the amount of off-gassing volatile organic compounds is 100 times greater than that coming out of a modern tailpipe,” said Molden. “This is from the tire just sitting there.”

I'm starting to see more and more homes in the area where I live, Southern California in the LA region, switching from green unsustainable lawns to some form of hardscape/ xeriscaping.

one of the rising trends is the use of old tires as a ground cover source. These have been shredded and processed with a small amount of coloring into something that very strikingly resembles and spreads like wood chips until you pick them up and feel them in your hands.

Of course it better solution would be to not have tires that are so toxic to begin with, but there are very few products into which the most unusable kinds of recyclable plastic streams can be fed, and tires are one of them.

Certainly most particulate matter, and it's not even close. Comparing particulates to gas emissions is difficult, so there's no way to say what's "most".

Either way, my greater point still stands: switching to EVs isn't a cure-all to breathing around cars.

Sure, I suppose this is where I find umbrage with the claim. Instead of “most” maybe try “a comparable quantity of”? (I’d cut to the chase by clarifying tyres and brakes are the principle source of particulate matter, a pollutant with proven harms.)

They spread differently. CO2 affects the whole planet, more or less. Particulates settle in the nearby area. They're different things.

The parent was worried about "noxious gas", not rubber particles. Cars with an ICE have tires as well, unfortunately.

Tires are only about 25% natural rubber; the rest is synthetic rubber, heavy metals, plastics, and additives. These get emitted as fine particulates that stick around in the air. They may not technically be a gas, but we breathe it in just the same.

I very much doubt that heavy metals such as mercury or lead are used to make tyres. I've only ever heard of steel belted tyres.

It used to be that wheels were balanced with small lead weights, but the use of lead for this has been banned in pretty much every western country, and wasn't contributing to road dust even when they were allowed.

"Hundreds of other ingredients, including steel, fillers, and heavy metals — including copper, cadmium, lead, and zinc — make up the rest, many of them added to enhance performance, improve durability, and reduce the possibility of fires."

https://e360.yale.edu/features/tire-pollution-toxic-chemical...

They didn't reference a source, and the claim is rather outlandish.

Cadmium and Lead are both quite toxic, and I'd be absolutely shocked if any tyre company in the western world used either of them anywhere near their products, let alone mixed into the rubber, which is insane.

"Tire fragments soaked in solutions with pH ranging from 3 to 8 did not leach measurable amounts of cadmium over a period of six week" from: https://www.echocommunity.org/en/resources/b1d9d1eb-afcb-472...

"Cadmium and lead concentrations were negligible." from: https://pubmed.ncbi.nlm.nih.gov/9085433/

"The low cadmium levels in their tyres was due to the efficacy of the zinc oxide purification process. In the nearly 50 years since the David and Williams study, Zn, S, and Cd refining has improved and this may contribute to low levels of cadmium being detected" from: https://www.sciencedirect.com/science/article/pii/S016041202...

So... it looks like tyres contain some Zinc, which many decades ago wasn't purified very well, which resulted in Cadmium and Lead being included as impurities in the Zinc. The industrial processes have improved and this is no longer a problem, but people are quoting tyre compound issues from the 1950s like they're still issues today.

Whoever wrote the article you linked couldn't be bothered to run a quick Google search to see if the problem still exists. That's unfathomably lazy.

PS: Not to mention that the lead added to fuel was a vastly bigger problem than any trace lead impurities that got into tyres.

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