I remember reading about tyre pollution recently (I was comparing electric and ICE cars and showing the impact on the environment of both - at around 50-150k kilometers the emissions from production and use even out and BEVs then have much lower impact - but it is highly dependent on the energy mix and whether or not do you plan to replace the battery). I found out that about 6 million tons of particles get released from tyres every year. The worst thing is that there are no regulations and it is difficult to check what the tyres are made of (as it's a trade secret). The particles can become airborne too, and some of them can cross the membranes inside of lungs - but the research about their effects on humans is scarce.
Related article from the Guardian: https://www.theguardian.com/environment/2022/jul/25/tyre-dust-the-stealth-pollutant-becoming-a-huge-threat-to-ocean-life