Particulate pollution has also improved since then. Makes you wonder what other ailments will mysteriously become much less prevalent when we finally get rid of ICE cars, and perhaps reduce car traffic in general.
Long term(as in multiple decades) we might want to switch maglev railways, as there is no friction to stir particles in the air from that. That would also remove the need for batteries whose production is probably harmful to some degree.
Infrastructure costs are gonna be fun though...
For completeness EV apply regenerative braking for a large proportion of use, which is for all practical purposes particle free. Obviously tire wear still applies but brake pad wear is largely reduced
So with EV you are getting rid of ICE particulates, CO2, CO, and NO2 (particularly on Diesel engines) and also drastically reducing brake particulate from brake pad wear.
And to be fair my intuition is that the health impacts of CO and NO2 is likely far more harmful then tire and brake pad particulates.
Having said all of that we would still be better off just having everyone using electric buses or trains within Metro areas at least.
It seems some people is working on that too:
"The Tyre Collective designed a simple device that collects microplastics as they fly off a car tire. As the group of designers explains it, their device helps on the path toward zero emissions by using electrostatic and airflow around the tire to capture the microplastics and other small particles that are shed over the lifetime of a tire."
https://www.ecowatch.com/microplastics-car-tires-james-dyson...
That's hilarious.
I'd be willing to place a bet there are 101 reasons why that sort of contraption will never be seen on the roads.
Its one of those things that looks great on a designer's CAD, and perhaps "works" in a carefully controlled lab simulation. Regrettably its quite obvious its not going to work once you throw good old real life at it.
If the system is broken, the only economically sensible way to fix the problems is to change the system. Fundamentally.
(In this case, the "broken system" refers to the idea that when we go to work, we have to bring two resting chairs, a couch, and a large coffer. And all of society should be shaped around this daily furniture transportation. Tire dirt is just the second of a very long list of problems caused by this idea.)
This is the problem for most of us right here.
Is there a major environmental/health problem with particulate from regular steel-on-steel railways? I would guess the iron particles don't travel very far due to their density and will mostly turn to harmless iron oxide.
Yes, as only extremely modern passenger trains have regenerative or resistive electrical brakes and even they need to do the last few bits of the braking process with the old friction brakes since electrical braking doesn't need at low speed.
Old trains, especially freight, still runs entirely on friction brakes - either metal or the new "silent brakes" that are a plastics composite.
Additionally, you have environmental concerns from oil and lube, which is why you should never fucking ever re-use torn out wooden railway sleepers. They are drenched in immensely toxic anti-rotting agents to begin with, and seep up all the oil and other contaminants (e.g. feces from bypassing old trains without closed-loop toilets).
The anti-rot agents (and, in case your local railway does pesticide spraying to reduce weeds, these too) will leech out into your flower bed and kill it off.
You still want friction breaks to hold you in place once you've stopped, but there's no strict need to use them earlier. Yes, current controllers may not be intelligent enough, but that should be fixeable without changing the power electronics, and only replacing their controller.
Europe still uses screw and hook/buffers for that reason, and it took well over a decade to mandate silent composite brakes.
Even the older non-inverter locos here use electro-dynamic brakes (afaik for economic/control reasons, as they are better than air for keeping speed during downhill sections under control), and the remaining ones will retire soon.
The screw and hook/buffers issue is more due to the distributed ownership of the freight cars, and early issues with certification of adapters between UIC central couplers and screw+hook/buffers.
Sure, there are situations where it's too steep to only brake the loco, but they aren't that common and adding some induction brakes to some of the heavier cars and preferentially using them shouldn't be particularly expensive. Sure, not cheap, but also not prohibitive for getting rid of friction breaks in the course of normal operation (well, some friction breaking may be needed from time to time to keep them in check and verify proper function.... but still a >90% reduction shouldn't be hard.
In tunnels, from "erosion from the wheels and brakes, and the rails", yes:
When we send them to poorer countries, as Germany has been doing with cars that fail the TÜV emissions test. Central Asia is full of German cars.
I suspect that the same is going on with recycling and emissions. Rich countries reduce their impact by moving it elsewhere.
It's likely to get smaller with time though, because e.g. diesel cars manufactured during and after the VW emissions scandal turn out to be expensive to repair once key components like injectors fail.
There's a whole market of refurbished injectors, flywheels etc., but buying such parts comes with a risk.
Also VAG products declined in quality in the recent years.
Anecdata: my father's 2018 Skoda CitiGo failed its emissions test because of a failed EGR valve - turns out it's a common problem - even in fairly new cars.