[Findecanor]

Some cities have streets where internal combustion engines are banned.

Some have bans on just diesel engines. Others ban combustion engines during some hours. Some inner-city congestion taxes have been introduced for health reasons.

[alchemism]

While I appreciate those efforts, and do not mind tobacco-free streets, I'll also note that some cities have unfiltered power plant exhaust falling on them, carried by the jet stream from other cities vast distances away, which care less about the problem. The local solution may not be the optimal solution.