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The problem of "brake dust" on human health and air quality has been known for a long time (https://phys.org/news/2020-01-air-pollution-effects-immune-c...) before that there were also issues with asbestos in brakes, but thankfully those haven't been used since the 90s as far as I know. This is the first I'm hearing about electrically charged particles though.

The bottom line is that proximity to traffic is horrible for your health and your air quality. Electric cars can help with some of the problems but don't solve all of them. The people with the least amount of money end up having to move to apartments near highways and so they often suffer the worst impacts, but I've seen very nice and expensive apartments and houses very close to (or directly on) busy streets. Noise is usually the obvious and immediate consideration, and I doubt many people are aware of the risks they expose themselves and their families to just by opening a window in the summer.

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If you looked nationally at wealth vs proximity to traffic, I would wager the "people with the least amount of money" are not the closest to traffic; are you suggesting otherwise? If only because of all the wealth that has come to cities in the last 20-25 yrs. Within that already wealthy urban demo I would agree, yes, the poorer wealthy are nearer to urban highways and thoroughfare than the wealthier wealthy.

https://www.cdc.gov/mmwr/preview/mmwrhtml/su6203a8.htm

"In the United States, it is widely accepted that economically disadvantaged and minority populations share a disproportionate burden of air pollution exposure and risk (26,27). A growing body of evidence demonstrates that minority populations and persons of lower socioeconomic status experience higher residential exposure to traffic and traffic-related air pollution than nonminorities and persons of higher socioeconomic status (5,28–31). Two recent studies have confirmed that these racial/ethnic and socioeconomic disparities also exist on a national scale (32,33)."

It's not surprising that minorities would be exposed to more traffic given the proportion that live in urban areas, but that doesn't rule out that the poorest in the country (minorities and whites) are not the most exposed. I guess my basic question is, are the poorest people still living in city centers? In my city the central, densest areas became some of the wealthiest, the quieter outlying areas the poorest.

> …that doesn't rule out that the poorest in the country (minorities and whites) are not the most exposed.

Setting aside race, to me it seems like "economically disadvantaged populations share a disproportionate burden of traffic-related air pollution exposure" makes this pretty clear. <shrug>

It's not 1950, everyone on this site has a 1+ GFLOP machine so there's no need to squash a bunch of independent variables down to one dimension or as you call it "set aside race." Unless you're not a hacker, that is.

Even into the 1960s wealthy black people were prevented from buying and living in the 'good' parts of even northern US cities.

Care to enlighten us as to the second paragraph? I only found some misc stuff, nothing appearing to be systemic or enshrined in law. In fact I see laws against such things being enforced more than lamented in searches.

Why do you assume that fine particulate is at the highest in city centers? It's often higher than average, but the highest is frequently outside of the city center, where highways have been constructed through pre-existing, poorer neighborhoods. The South Bronx is the famous example of this[1].

[1]: https://www.theguardian.com/us-news/2019/apr/04/new-york-sou...

> I guess my basic question is, are the poorest people still living in city centers?

I suppose that there likely are small numbers of people living far outside of cities and away from traffic, like up in the mountains of Appalachia or living off the grid in tents or in communes deep in forests, who are poorer than people you'd typically find in urban areas, but it's still the poor in the US who are dealing with the worst of the harms traffic causes compared to the better off/wealthy. They're also the least able to mitigate those harms or deal with the fallout caused by them.

In Seattle, in the densest parts of the city are glass towers that certainly have filtered HVAC, and the poorest parts of the city are relatively low-density areas near the port (particulates from diesel trucks and ships), the cement plant, the nucor steel plant, the highly polluted duwamish river, and boeing field.

Density doesn't equal exposure.

For a very concrete example of this, within a city, see I-580 vs I-880 in Oakland: https://en.wikipedia.org/wiki/Interstate_580_(California)#Tr...

EV use of Magnetic Braking reduce brake wear by alot . With One pedal driving in city not using brakes at all

I almost never use breaks. It is a game for me, so I'm conscious of any time I have to use them.

On the other hand, EVs unfortunately pollute more with tire particles (thanks to both higher torque - especially from 0 - and higher average mass).

> EVs unfortunately pollute more with tire particles (thanks to both higher torque - especially from 0 - and higher average mass).

I wonder how much the higher torque of EVs is a real issue? Although they have the potential to do more aggressive acceleration and produce more tyre pollution, the Teslas I see leaving traffic stops seem to be accelerating the same as ICEs.

EVs also tend to be heavier than their ICE counterparts.

> EVs also tend to be heavier than their ICE counterparts.

As the parent comment said - but I was questioning about whether increased torque has an actual impact on tyre wear.

Indeed I wonder at “normal” speeds (not racing say) does torque matter or is wear dominated by total miles driven? If I zoom to my destination do my tyres wear substantially more than if I take a more sedate approach?

(Certainly when I was young and dumb my clutch wore more when I went dashing about).

yes

In my experience, someone who is new to EVs will tend to do a lot of short, fast accelerations to explore how the vehicle performance. That happens mostly in the early stages of using an EV and after a while they settle in to a more normal (ICEV similar) acceleration pattern.

I’ve driven an ev for the last 3 years (over 100k kms) and find my tires last about half as long. So yes, it has a big impact.

Do you have hard numbers on the tire particle claim?

We have anecdotes of Tesla owners saying they go through tires more often. But I’ve also heard car fleet owners with both EVs and ICE saying they see no difference between them.

So I’m inclined to think this is entirely dependent on the specific EV. You can get an EV without significantly more weight than an equivalent ICE, and you can drive them in ECO mode where the torque curve is extremely gentle. I don’t see any reason why you’d have more tire particles in that scenario.

I think there are pathways to have less tire wear on EVs than with today’s ICE vehicles. Batteries with higher energy density would obviously help, but I think there are things you could do with the accurate control you have over the torque on the wheels, or making true all wheel drive with torque vectoring more common.

I have a Ford Focus EV - still haven't replaced my brake pads - 7 years strong. Finally replaced my first set of tires last winter.

I've seen adverts for Chinese luxury apartments touting the built-in HEPA filtration systems. Seems to be a must-have if the air outside is polluted. Nobody seems to even think about this in building codes in the West. Especially, as you say, for apartments near major roads.

Modern homes in Germany have ventilation with heat exchange which have some sort filter system.

https://de.wikipedia.org/wiki/Kontrollierte_Wohnrauml%C3%BCf...

Filtration is a very good idea. HEPA filtration for residential use is dumb.

A HEPA filter must remove at least 99.97% of aerosols 0.3μm in diameter. A filter which removed 99% and blows air 1% faster will remove just as much, or one which removes 50% and blows air twice as fast.

For recirculating air, all of those accomplish the same thing. Some of those have much higher noise, running costs, and general upkeep than others.

HEPA makes 100% sense for something where 100% of air passes through it. If you want an exhaust on a facility which handles biohazards, a vacuum cleaner kicking up dust, etc., sealed HEPA 100% is the way to go.

That's not what happens in a residential building, though. For that application, it's just bad engineering.

would be about time we HEPA'd everything in health care

Why?

HEPA doesn't matter unless you have a sealed system. An open door or a cloth curtain means the 99.97% means nothing relative to 99%.

Isn't the point to have a positive pressure system, so unfiltered air doesn't come in?

A hospital has many rooms, hallways, etc. Which is under positive pressure?

If you have two patients, they should both be isolated from each other. Which one gets the higher pressure, and which the lower?

> The people with the least amount of money end up having to move to apartments near highways

In Dubai prime real estate is along the major highway Sheik Zayed Road. It’s funny how these things can be cultural.

Going by the look of the images on it's wikipedia page, most of the people next to that road aren't at/near ground level. I don't how many stories up you'd have to get before the pollution and noise aren't a problem, but I'm guessing the air only gets fresher the higher you go.

Some of the reason why poor areas in the US are around highways and busy streets have to do with the history of redlining (https://phys.org/news/2024-02-highways-historically-redlined...). Even today when a city wants to build a loud/smelly/polluting highway or a factory or a landfill or a sewer treatment plant it's the poorest areas that are the least able to fight back, and putting them in the areas where poor people are will mean the least amount of inconvenience for the wealthy who often live far away from those neighborhoods. After a source of pollution is in place, very few people want to move in right next to it, so any houses there tend to be inexpensive and may be the only housing poor people can afford which further concentrates them into those areas.

As someone that lives in Dubai, this isn’t accurate. No one wants to live right by Sheik Zayed road. People want to live by the sea on the Palm for example, JBR, or perhaps in the Marina area.

Driving up SZ road, all you see are tons of shitty retailers and car dealerships. Trust me, wealthy people especially are not living next to it.

Please take a look at the high-rise along sheik zayed in business bay, around down town and World Trade Center and explain to me how those are low end living. It’s all 4 and 5 star hotels with significant portions dedicated to long term (yearly) contracts.

It’s only Al Quoz that is car dealerships. But on both sides of Al Quoz you find high-end, high rise

> before that there were also issues with asbestos in brakes, but thankfully those haven't been used since the 90s as far as I know

I’d be careful with assuming that. A lot of consumables are imported directly from China, and the cost of car maintenance can be eye-watering, so it’s exactly the type of part I’d expect to be procured as cheaply as possible.

People care about the brand of tyres on their car, I don’t even know of any brake pad brands.

DBrembo or AP Racing are somewhat well known brake manufacturers, but only matter for sport cars/motorbikes.

OTOH I don't think most people care about tires either.

...but I've seen very nice and expensive apartments and houses very close to (or directly on) busy streets.

Some of the most expensive houses in my neighbourhood are the closest to the highway. I just tried to check, but none of them are for sale right now. Traffic only decreases four hours at night but it never really stops. Only the noise is a big no-no.

Electric cars can help with some of the problems but don't solve all of them.

In the case of brake dust specifically, presumably electric cars are worse because they're quite a bit heavier than ICE cars.

What you're saying is completely true for tire particulates, but if you drive an electric car normally you're almost never engaging the brakes. Since almost all normal amount of braking is in the envelope of where your regeneration braking can take all of the power.

This counts even for hybrids though. A friend of mine had to replace his brakes after over 10 years and 180,000km on his Prius for the first time. Not because the brake pads were used up, but because the brake rotors started to rust too much from not being used.

Of course if you're one of those people that floor it and hard brake at every stop light, this doesn't work, but for most cars it works really well.

ICE cars can use engine braking, and here in Sweden it get focused as part of the driving license and associated training. I recall even getting the recommendation to "exercise" the breaks once in a while in order to assert that they actually do work when you needed, since breaks that don't get used enough can get rust buildup.

Of course, this is also part of driver training in Germany. But the engine braking on EVs makes brakes only necessary for emergency braking if you're not driving like a maniac. With ICE engines you still need the brakes a lot more. Especially downhill.

I don’t think this is a 1:1 comparison though. Electric cars can utilize regenerative braking, which can significantly slow them down before needing to use friction from brake pads in order to stop.

You can engine brake with a gas car if its manual transmission too

You can engine brake with a lot of automatic vehicles as well, since they’ll still have semi-automatic modes. I drive a car with a CVT and I’m able to “down-shift” for engine braking by using fake gears at specific ratios.

I feel like the distinction here is that you have to go out of your way to do this with ICE vehicles? Maybe I’m in the minority then, but I never do this with my car (which has CVT).

I tried it a few times, thought it was a gimmick and now I just use gas or brake.

I'm getting sick and tired of hearing this argument being repeated over and over again.

Electric car use regenerative braking. Yes they're heavier but their brakes barely get used...

They only get used at very low speed to bring the vehicle to a stop (low energy), or in case of emergency braking.

I’d go weeks at a time without touching the brake in a Leaf.

I might never replace the pads.

what about the NYC subway / PATH train? The air quality there is pretty bad -- the trains use standard brakes.

I wouldn't spend more time on underground transportation systems than I had to. https://nypost.com/2023/05/13/subway-has-alarmingly-high-pol...

And EVs make some problems worse, such as tire dust because they're heavier than an equivalent ICE car.

Yep. Pretty much any kind of wear and tear part that is on an EV wears worse compared to a similarly powerful ICE. It's probably a wash or better because they don't use petroleum products for propulsion, but it is definitely a thing that needs to be considered. EV's are not some kind of panacea.

Except brakes, since they are rarely used due to regenerative braking. Tires, on the other hand, do wear faster than a lighter ICE car. My EV has almost 30,000 miles now and will need tires soon, but other than washer fluid, it has had no other consumables or wear items replaced.

Though to be fair, the tires on my previous ICE vehicle only lasted about 30,000 miles before they needed to be replaced, OEM car tires are often not long lasting. Brake fluid is due to be flushed next year, but not due to use of the brakes, just due to time.

Tire life also depends on where you live. In Atlanta, GA, I specifically haven’t made it more than 20K miles on a set of tires be it wear or road hazard. The issue with nails here is so bad there’s a guy on a bike picking them up with magnets.

https://www.fox5atlanta.com/news/atlanta-magnet-man-alex-ben...

That 20K set of tires had a slow leak from a nail that was patched incompletely. On the new set I had to replace two using the hazard insurance I purchased after three months and two thousand miles. I expect to use the insurance again.

I now have an EV with sport summer tires. They’re at 5K miles and have a screw embedded in one tire since about 400 miles. That tire was deemed to be safe and best left alone as it’s presumed to be running through a rubber block only. I’m just running it until it goes flat assuming it doesn’t manage to survive its whole expected life span.

Realistically I’ll end up running something else over this spring once construction gets into full swing.

You should probably change your air filter.

> Yep. Pretty much any kind of wear and tear part that is on an EV wears worse compared to a similarly powerful ICE.

Probably accurate if you exclude the brakes and ignore the fact that removing an ICE engine from consideration also removes nearly all the tricky bits that wear out on an ICE car.

Actually, the opposite is true because they make heavy use of regenerative breaking.

What EV’s produce more of is tire particulates due to weight.

PS: And now the post says tires.

They said tire dust, though, and I don't see an "edited" note there

Said breaks when I replied, though the article is talking about breaks so it’s an easy slip up.

Brakes. Different thing

Sorry, I meant tires, but momentarily mixed it up with brakes.

Thanks, it's fine.

I thought the post had changed, but I wasn't 100%

The same applies to tires though. The driving style EVs encourage (avoid heavy braking to allow regenerative charging) reduces tire wear too.

EVs also don't really use brakes. They mainly use regen braking. 50k miles and on the same pads.

My standard non EV gas car is 45k same pads?

Except mine are basically new.

I should add a little bit of honesty here. I did replace my brakes but only because they were rusting from not being used enough! So I bought stainless steel pads and those look great.

This is true about EVs, but it all just depends on how hard you are on your brakes. I routinely go 70k+ miles in ICE cars with the same brake pads. My mom on the other hand had to change hers about every 30k miles. YMMV.

a lot of that can depend on your commute. If you commute over hills, you can expect shorter time between replacing brake pads.

Having said this, if you can go 70k+ miles with the same brake pads, you could likely go much further than that if the car had regenerative braking.

I haven't really had to engage the friction brakes on my EV in the past 30,000mi, other than intentionally having a few hard stops to scrape rust off the rotors from not using them for so long.

It's a shame this is used as an excuse to keep the heavy ICE SUVs and trucks. There are many EVs lighter than an average pickup truck.

If people really cared about this, they'd demand train-based public transport instead (no tires! fully electric! self-driving too!), or at very least limits on car weight regardless of the engine.

Most drivers are virtue signalers. Until we have eco batteries or hydrogen buses and trains are the only real eco solution.

Unfortunately buses and trains are only viable above a certain density, and many communities exist configured in such a way that they are intentionally low density. While metal mining might have an environmental impact, abandoning millions of existing homes and building new ones in cities not only also has a large environmental impact (concrete also isn't great for the environment), but it is also politically, economically, and practically unviable.

A mix of solutions will be needed to fix the variety of different and unique problems that exist.

Busses are viable as long as you make them viable. If you have a busstation at a 1 km distance you can make it viable in most places even with the mega sprawl of the US. The economical incentives of a car economy is perverse it is the tradgedy of the commons distilled.

Most of the US has single digit numbers of people per square km. And the average daily commute is 61 km. And suburban sprawl had led to the decline in city centers. Low density, high distance, and poor directionality are very significant challenges for planning a bus line.

Have you used bus systems in the US? Even in cities that have made a large investment in bus service, it can be a challenge.

I personally loved taking busses and trains when I lived in the city. I didn't go far but with a pass I'd take them all the time. I now live in a suburban sprawl and I can never convince my wife to bus it. She usually has a point: it's pretty inconvenient to get from our home to a bus/train stop. I live by a train but would love it if they were electric though that'd do nothing to reduce brake dust.

I know it sucks living in the US without a car, I do think it is important to know that it can be done. You are going to have to prioritize though. I've lived carless in some of the most car dependent places of the earth, including the US so I know what makes that a great deal.

I closely know people who have lived in extreme rural areas of the US without a car. You are right that it is possible. But it certainly presented significant challenges. There's a reason why people buy cars in the US.

What is wrong with overhead electric for trains? Why some oil company shill nonsense about hydrogen?

They're ugly but I'd love them if I had them. Why the hate for hydrogen? Mark my words, we're being forced to upgrade our HVAC systems to be "green" the use TONS of electricity when in 20-40 years, we're going to do it all over again to move on to hydrogen. I'm already spending $300 a month on electricity using "green" tech. The second I can produce my own hydrogen, I will.

> Most drivers are virtue signalers

An amazing claim.

Majority don't buy their electricity from green suppliers and don't care where their batteries come from. Cobalt mines are hell. Either way, I stand by what I said. Spending 40k+ on a 10 year product that will cost 20k+ to refurbish isn't green. My 12 yo EV battery cost more than the car to replace.

In some places it’s fairly hard to get power that isn’t generated by renewables. In New Zealand the grid is 80%+ renewable and my supplier is 100% renewable.

My EV cost $13k and was fairly new at purchase.

In IL there are no green providers but 3rd parties provide it somehow from TX. I'm not sure how it works but it's quite expensive. I did it for a few years but stopped. Now, with my increase in energy usage due to moving away from gas, it's hard to justify. In the United States, we want to move everything to electric and I believe that's a mistake. Not without nuclear power to subsidize costs. I'd imagine my monthly costs would be closer to $400, which I believe to be insane.

Trains also have brakes which produce large quantities of fine particles.

This is especially a problem in enclosed spaces with limited ventilation: on parts of the London Underground, air pollution in the tunnels can be many times worse than on the streets above.

Trains are also way more efficient than cars at transporting people. If everyone taking the train was driving instead you can bet air quality would be way worse.

Why do you think that was an excuse for ICE vehicles? That’s your own biases showing. I’m anti-car in general, and very pro public transit.

EVs aren’t going to be the savior of climate change. They do some things better than ICE cars, but do some things worse. Denying those worse things is just putting your fingers in your ears.

This depends on your driving style. I was listening to a person from a lease company on the fully charged podcast recently who literally runs the numbers on their fleet of EVs calling this out as largely a myth (one of several). At scale, they are not really seeing a difference relative to ICE cars. And they'd know because with a lease car, replacing tires is their problem.

Some people of course drive their EVs aggressively and wear out the tires faster. But that's true if you have a muscle car too. Doing donuts in the parking lot just wears out your tires. And if you are in Germany and like seeing how fast your car can go regularly that also wears out your tires. The driving style is a much bigger factor than the weight of the car.

But otherwise the numbers are about the same for ice cars and evs in terms of frequency of needing tire replacements. For most people the novelty of abusing their tires wears of quickly.

And because most EVs use regenerative braking, the main issue with the brakes in EVs is that they are used so infrequently that they need to be replaced because of corrosion issues. You actually need to use the brakes once in a while to keep them clean and functioning apparently.

A model 3 is no heavier than a 3 series.

Not by my math unless comparing the hybrid.

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