Librature has a list of DRM free individuals and small presses https://libreture.com/bookshops/
Oh I forgot also if you check the details on kobo, some of the books are sold DRM free. Mostly I think it was from Tor, but could be other publishers as well.
Tires are a large if not the the largest source of microplastic pollution.
https://www.thedrive.com/news/tire-dust-makes-up-the-majority-of-ocean-microplastics-study-finds
Yes by being far more numerous private vehicles are the largest source, but buses will also be contributing too.
Related sources: “The biggest source of microplastics in California coastal waters? Car tires” https://www.cnn.com/2019/10/04/us/microplastic-pollution-car-tire-trnd/index.html
“Pollution from car tires is killing off salmon on US west coast, study finds” https://www.theguardian.com/environment/2020/dec/03/coho-salmon-pollution-car-tires-die-off