How do you know the dust was specifically brake dust?

Good point.

I'm quite sure it was brake dust because during COVID 19 lockdowns everything was the same (heating etc) but streets were void of cars.

Then I've read some scientific article about brake with pics and it looked exactly as what I got inside my house.

I can't conclude 100% it was it (or just it), but it seems to be the most probable cause along tires.

Ah, that's interesting. Although I imagine cars kick up a lot of old-fashioned dirt dust from the road and swoosh up some more of that from the sidewalks as they drive as well.

There was an article on the topic just today on the economist

https://www.economist.com/science-and-technology/2025/04/11/...

I live in a house next to a moderately busy street with car traffic and also some public transport (bus lines). I noticed that the windows (and frames) facing the street get dirty much faster than the windows facing the garden. The dirt on the street side is also pretty gross, sticky and hard to clean. It's just an anecdodal observation, but I could not come up with a better explanation so far.

I had a balcony overlooking a highway in Toronto once, and it got super grimy as well. I think all the different kinds of car emissions combine into some sort of super bad tarry crap that then collects every kind of passing dust particle.

Only electric vehicules are allowed inside the ZFE.

Doesn't answer the question though.

Isn't it more likely that it was tyre dust? Every vehicle (more so the heavier ones) is continually depositing tyre dust into the air, whereas brake dust will only be produced when slowing (and hardly any for regenerative braking vehicles).

Electric cars (some hybrids) use their brakes less due to regenerative breaking. So thats something at least.