Jester.. you got it.
When looking at a drop of 50 mg e-liquid, you're looking at a material that's 50 mg/mL in nicotine (or there's 2.5 mg of nicotine in that drop of e-liquid).
Compare to pure nicotine, you're looking at a material that's 1,010 mg/mL in nicotine, (or there's ~ 50 mg of nicotine in that drop of pure nicotine).
Also, with e-liquid, the matrix itself (the propylene glycol) shields the skin from the nicotine since PG apparently does not absorb dermally, thus the active transport of nicotine does not occur as it would with pure nicotine.
I'm not going to say a drop of nicotine on your skin, quickly washed off is going to kill you. At the very least, it's likely to be enough absorbed rapidly enough to make you quite sick.
A drop unnoticed
might kill you, but that drop
very likely will kill your kids and pets since 1) they're smaller and 2) they're probably not smokers, so they've got zero tolerance.
Also, if you have difficulty with the concepts of mg/mL and dilute solutions vs concentrated chemicals.. you doubly shouldn't be fooling with this stuff. Funny how those with the least training and expertise are the most eager to get hold of this stuff.
Go here and think about it if you're having trouble getting rid of the pure nicotine bug.