In another odd juncture of chemistry and bicycles, today is widely known as "Bicycle Day" in honor (?!) of the bicycle ride that Albert Hofmann, the discoverer of LSD, took back in 1943 while loaded up on said drug. Not being one to advocate recreational drug use[*], I do find the tale a little questionable. Not the ride itself when Hofmann intentionally took the drug, but what happened leading up to the trip, when he first suspected the psychedelic nature of the drug after accidentally absorbing some through his fingertips.
I'm not an expert on skin absorption of drugs and chemicals, but I have noticed over the years that the skin of the finger tips and palms seem to be far, far less porous than that of the rest of the body. For example, I've had poison ivy outbreaks (caused by absorption of urushiol) all over, but never in the palms. I've talked to others who spend time in the woods and they all report similar experiences.
So maybe that first exposure was an "accident". Or maybe it wasn't. But I seriously question the claimed exposure route.
[*] Not me. I haven't even tried pot! Imagine how embarrassing it would be to appear before the Senate Judiciary Committee or some such entity and having to state that fact? Think someone that out of touch with society would stand a chance of getting confirmed to even dog catcher?