IIRC in MSDS class WD-40 is pretty bad on "health".
Surprisingly enough from what people say about it.
Anyway, I would not get that stuff on or in you just to be to be safe.
(Same with "RTV" sealants.)
I guess we get what we pay for?
I use WD 40 only because Kroil is
1. Expensive.
2. Harder to get.