Touching a Toad Gives You Warts
"The warning that handling a toad or frog will cause warts to grow on your skin."
Warts are caused by human papillomavirus, a human-specific virus with nothing to do with amphibians. The myth likely comes from simple appearance: toads have bumpy, glandular skin, and people assumed those bumps were a contagious growth much like a wart. They aren't warts at all, they're glands, some of which genuinely secrete mild toxins, a real, if different, reason to wash your hands after handling one.
Myth vs. FactThe bumps on a toad's skin aren't warts, and human warts can't be caught from an amphibian.
Sources: Multiple herpetological and dermatological sources, including Smithsonian Magazine and Burke Museum.