Completely ignore regenerative braking - bias? : > A car’s exhaust can put at most 1.9 mg of particulate matter into the air for each kilometer driven down. E

Completely ignore regenerative braking - bias? : > A car’s exhaust can put at most 1.9 mg of particulate matter into the air for each kilometer driven down. EU rules are slightly looser at 4.5 mg/km. Could brakes come close to that? Well, depending on the vehicle, disc brake pads have 100 to 400g of friction material. Perhaps 80% of that material is worn away before replacement, which happens after something like 65,000 km. Assuming 200 g of friction material, that suggests an average of 4 brakes × 200 (g/brake) × 0.8 / (65000 km) = 9.8 mg/km of material lost from brakes.