They are considered safe today, whether that changes in 5-10-50 years time is unknown. Same with anything else that is considered safe today, you can accept that it is safe, or fear that things might change down the road.
Cigarettes are a bad example though, in fact everything you gave is an example of chemicals. They were all known pretty quickly to cause issues, however there was next to no regulation at the time - and is kind of the reason things are heavily regulated today.
Anyway by the logic you were putting, you must be fearful of everything as nothing can be considered 100% safe, and anything could change. Or just develop a basic understanding of the underlying technology and form your own opinion. Personally, I don't believe the EM produced by this kind of tech is above any dangerous thresholds and so causes no damage - this is something backed up by the people that regulate this stuff. So I'm happy.