Where I live, there are toad carcasses here and there, usually run over by cars or having met some other untimely end. And of course, children will sometimes pick up toads with their bare hands - or worse yet, who knows if someone will touch one of those smashed toad carcasses with their bare hands!
Now I am reading all sorts of alarming stuff on the Internet about what toad toxin can do to humans, but then again I handled toads with my bare hands as a kid and I’m still relatively intact/unharmed.
Did the toads simply not release toxin when I was holding them, or is the toxin already on their skin surface?
What about the toxins INSIDE a toad? A smashed toad corpse might exude toxins from its smashed organs in a way that an intact, live toad wouldn’t?
The only toads in the US that are even remotely dangerous are the Colorado river toad and the Cane toad.
Even those are harmless if you was your hands afterwards.
All the common toads (like the Fowler’s toad) are safe to handle. Even dogs are not in much danger from the big toads, because the toxin is so bitter.
Toads produce most of their toxins from glands ( parotoid glands ) behind their eyes. Some tiny amount may be produced elsewhere on their skin. No toxins ( that I’m aware of ) are produced internally. The alkaloid toxin is only very weakly active on human skin, it must be ingested to have an effect. So unless the OP contemplates handling toads or their corpses then licking his/her fingers, danger is minuscule.
Children may of course put all manner of strange things in their mouths, as may dogs. Luckily, toad toxin apparently tastes really bad, enough so that most dogs ( and presumably most children ) will not persist in mouthing toads or exudate from toads, live or dead. Only especially persistent dogs that can’t seem to give up on a bad job actually ingest sufficient toxin to be dangerous. Florida is overrun with Cane Toads and with stories of poisoned dogs, but most such ‘fatalities’ happened to ‘someone my cousin talked to’ or equivalent. Actual poisonings are uncommon. You can safely relegate toad poisoning to the Things I Really Don’t Need To Worry About bin.
My wife worked with a guy who, on a dare, licked a toad. He ended up blind.
His nickname around the office was “Kermit”.
No, he didn’t. This is bullshit.
If you really, really want to get “toxic” stuff out of a toad, you have to capture the right species, milk its poison glands, and then consume that poison. It takes effort and intent.
Depends upon the semantics of “blind”. Whether permanent or just temporarily blinded. “Ended up” implies permanent, but is more likely an issue in the re-telling of the story. Given the guy clearly retained his job, one suspects the effect was not actually permanent.
Some idiot trying to lick a Cane Toad is quite likely to distress it enough to engage one of its defence mechanisms, to spray toxin from the glands on the back of its head. This will cause temporary blindness if you are close enough to get sprayed in the eyes. Trying to lick the toad is going to be more than close enough.
Cane toads cannot spray toxin. The glands exude it, but there is no mechanism for squirting across any intervening distance. The only “close enough” is touching. That said, even just the skin secretions of many annurans is highly irritating if it gets into one’s eyes. Handling one then rubbing one’s eyes may result in temporary blindness.
Right, but a toad getting run over a car would ooze the toxins out of those smashed poison glands…?
Yeah. I was miss-remembering the problem. Rough handling of the toad is sometimes enough, as if the toad is gripped behind the head, finger pressure in the right spot has been known to squirt the toxin, and eyes have been known to be right in the wrong place. It may be that the glands may have evolved to squirt when pressed, probably more as an effective way of delivering a dose into the mouth of a predator.
I’ll accept that in Cane Toads the massive parotoid glands may be somewhat turgid with stored toxin. And rough handling including accidental hand/finger pressure in just the right spot, combined with rapid movement of the toad (as in grabbing or snatching it) may result in some droplets of toxin flying off, to land wherever including possibly in someone’s eye.
If we broaden the definition of “squirt” to include the above scenario, I’m on board. 
I don’t though think this can be applicable to the vast majority of other toads that lack the Cane Toad’s outsized parotoid glands.
And the chance of you ingesting this roadway hash is…?
Not ingesting, but contact with skin.
Where do you live?
Poem from Jon Arbuckle
*
I have a buddy, my buddy’s a toad.
He looks kind of muddy, he’s flat on the road.
But he is my buddy, my buddy he’ll stay.
'Till he’s peeled up and sailed away.*
Serious answer – toad toxin has very little activity on your skin. If you rubbed the straight stuff on your arm then undertook an extended hike in the desert with no water to wash it off, you might get some irritation. Otherwise, soap and water handles any conceivable topical exposure.
Perhaps less seriously, I can’t help but notice that you keep returning to a scenario involving smashed toads and skin contact. Tell me, what exactly are you envisioning? Is it fun, or kinky, or what? 
Damn, that’s old school. Garfield Gains Weight from about 30 years ago, am I right?
Yep, 35 years for the book. Original comic date is 5-3-79.
Was his frog buddy’s name Jeremiah?
Jeremiah was a bullfrog.
My dog tried to pick up a toad. Made the dog drool and foam at the mouth, but otherwise no lasting effects. The toad hopped away.