Do those blue lights at the nail salon really work?

the ones you put your nails under after getting them done. and what do they do?Do those blue lights at the nail salon really work?
They're UV lights. They do increase drying time of the nail polish chemicals and hardens them faster too. But they aren't too great for you...Do those blue lights at the nail salon really work?
Supposedly they help dry your nails faster. But i found out they're made with UV light so that's kind of bad.





I saw this picture of someones finger tips having holes in them because of the UV light. haha. it was gross and now i cant find it.

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