Blacklight Inks are nothing new. They've been around since the early 2000's. If they were a problem, they'd be off the shelves by now.
There are two types of UV ink, One is the type in the picture, it's an actual color that can be seen by day and will glow various shades under blacklight.
The other is a whitish/greenish color that is somewhat invisible by day and bright when nearby a blacklight lamp/
While I don't have any UV tattoo ink on my body I have given given enough UV tats to know a few things:
Warning: They aren't approved by the FDA, but then again, NO tattoo ink is.