In order for the juice to be harmful, you would practically have to bathe in it long enough to build up 50mg of nicotine *in your system*, and long before that, your body would be telling you, by means of a wicked killer headache that you are ingesting too much nicotine. Of course, we DIY mixers of the bottles of 100mg Nic wouldn't be silly enough to be splashing around in it, the stuff is too danged expensive to do that with! LOL
This doesn't preclude just being sensible!! The stuff is sticky and icky anyway, right? So, if you get it on you, just wash it off.
If you are concerned about overdose, look up the symptoms for nicotine poisoning. If you fell asleep on your desk, and spilled your bottle of 100mg Nic and you slept in it for a bit, then call your poison control center.
Honestly, I am not making light of it, just that you would really have to make an effort to harm yourself with the ejuice. It would take a really long time, and prolly not work all that well. Rather, just enjoy it and remember it's been proven that you DIE from smoking cigarettes and you can overdose from drinking too much water.