In New York City, congestion pricing leads to marked drop in pollution

> Particulates issued from tailpipes can aggravate asthma and heart disease and increase the risk of lung cancer and heart attack. Globally, they are a leading risk factor for premature death.

Minor nitpick, but tailpipes aren't the primary source of emissions. The study is about PM2.5[0]. which will chiefly be tires and brake pads. Modern gasoline engines are relatively clean, outside of CO2, though diesel engines spit out a bunch of bad stuff.

[0] https://www.nature.com/articles/s44407-025-00037-2

It's true that brake dust is the primary PM2.5 emission from vehicles in an urban environment. However the PM2.5 component from tail pipes are still very significant, higher than the contribution from tires.

The order is:

1. brake dust 2. road dust 3. engine emissions 4. tire dust

https://www.sciencedirect.com/science/article/abs/pii/S00456...

https://electrek.co/2025/05/27/another-way-electric-cars-cle...

and would it be true to say that regenerative braking on electric cars reduces significantly this dust?

Absolutely. Nearly eliminates. Even non-plugin hybrids have greatly reduced.

There was a "study" going around claiming otherwise, which sampled air captured by passing vehicles with a trash bag on a busy road, claiming EVs did not reduce brake dust, but even my brief summary here makes it extremely obvious how flawed this "measurement" is.

For those of us unclear why collecting air from passing cars to measure particulates is obviously flawed, could you elaborate?

EVs unfortunately do increase tire particulate, as well. Fairly significantly. It's not obvious to me that the decrease in brake dust isn't made up by the increase in tire dust.

The removal of the tailpipe emissions is really where EVs shine from a pollution standpoint. If you turn on your car in your garage, you don't die anymore.

EV brake pads don't hardly wear down, so they obviously can't have nearly the same amount of brake dust, yet the "study" showed they did. I'm guessing there's brake dust on the ground being kicked up.

> EVs unfortunately do increase tire particulate, Fairly significantly

In the USA, mass of EV is not significantly different than the alternative choice. EVs do not have increased tire particulate. If in Europe extremely lightweight tiny cars are actually a likely substitution for nicer, heavier EVs, then it seems reasonable that tire wear will increase proportionally. There's a lot riding on that "if" though.

It's not just the fact that EVs are heavier than the non-EV version of the same car, it's also that the regenerative braking means that the tires are dissapating energy that otherwise would have gone to the brake pads or to air resistance. Tires wear way faster on an EV, their lifespan in miles is generally much shorter.

The engines are absorbing the energy that would have otherwise gone to the brake pads.

Tires apply the braking force to the ground in exactly the same manner on both EVs and ICE vehicles.

Firstly, the motors absorb half the energy. The other half goes to the tires. It would be great and efficient if the motors could.absorb it all but unfortunately physics doesn't work that way.

Secondly, if you've ridden in an EV, you would know that the drivers/cruise control often apply regent braking in situations where an ICE vehicle would have simply coasted to a stop. Hence more wear.

The tires wear the same amount here because either way, the car decelerates by the same amount at roughly the same rate.

No, it doesn't.

With the ICE car, if you want to go 55, you might accelerate to 57 and then coast down to 55 without using brakes.

With an EV you might accelerate to 57 and then brake to 55 when you let off the accelerator.

Tire wear is a function of how often you use your tires to slow down the car. With an ICE car that's every time you hit your brakes. With an EV that's both brakes and regen. An EV's time spent braking or regenning is more than the time an ICE car spends braking.

Someone could design an EV that behaves the way you describe, but aggressive regen sells better, so no one does.