Copper is still very common in brake pads, both in the semi-metallic and ceramic varieties. California phases out copper-containing brake pads starting in 2025.

Now that you mention it I think he did mention California. It's entirely likely he said "are banning" and I took that as present tense and not future tense.

Copper is used as bottom-coat on sailboats, it's also used as a non-hormonal contraceptive IUD material.

I don't think it's terribly harmful for humans if it's safe for a women's uterus. California tends to be exceptionally concerned for the environment in general. All that copper dust making it into the coastal marine environments isn't going to be good for it, considering the same stuff is used to keep marine life off boats.

edit:

"The issue has been under consideration since the 1990s, when cities south of San Francisco were having trouble meeting Clean Water Act requirements to reduce copper in urban run-off flowing into San Francisco Bay. Preliminary studies indicated that brake pads were a significant source of copper in that runoff. Tiny amounts of copper fall onto the streets and parking lots every time drivers step on their brakes."

from https://www.copper.org/environment/impact/copper-brake.html

As I suspected, it doesn't appear to be primarily a human toxicity concern. It's to protect the marine environment.

Weren't brakes made of asbestos at one time?

Canada banned asbestos brakes this year. Brakes are still exempted under US asbestos bans. Manufacturers and repair shops avoid them for obvious reasons, but they're not illegal.

https://www.baltimoresun.com/news/bs-xpm-2006-05-04-06050400...

https://canada.autonews.com/article/20180107/CANADA/18010983...

they were. But they used asbestos in a lot of things back in the day. I worked in a building with asbestos in the floor tiles. When they did constructions that involved removing the tiles, it became a big deal.

Asbestos isn't that harmful, until it goes airborne. My understanding from research (I worked expanding a landfill that took asbestos at one point). is that the particles are too small to be caught by our bodies defenses and when it ends up in your lungs its cancerous. Asbestos in brakes seems like a bad idea.

see: https://en.wikipedia.org/wiki/Mesothelioma

There's another thread that claims that was 50 years ago.

I believe a lot of the stopping power comes from ceramic cinders in the pads. Those showed up in high end bicycle brake pads about 25 years ago, and I think they were old news in high performance cars before that. I have a fuzzy recollection that they trickled down into mid-tier vehicles not long after that. 2000-ish?

Yes. Napa and other brake manufacturers are called into lots of mesothelioma trials. Brake pad exposure is usually smaller contributors to such cases. That is, the victim often had much worse exposure other places, but they still look at how much brake pad exposure the person had too.

I don't know about copper in particular, but metallic content is very common in sport or racing pads for additional 'bite' (higher friction) and heat tolerance.