Pollution from cars goes beyond just exhaust, also coming from road wear and brake dust. New research shows that brake dust may be more harmful than car exhaust, causing more damage to human lung cells in lab experiments. Surprisingly, newer brake pads without asbestos were found to be more harmful due to high levels of copper, which can worsen asthma. Treating brake dust with a copper-neutralizing chemical could reduce harm. California and Washington have passed laws limiting copper in brake pads, but brake dust as a pollutant remains largely unregulated. Electric vehicles may help reduce pollution from brake pads by using regenerative braking.
https://e360.yale.edu/digest/brake-pads-lung-damage-study