A version of Crash for the A man dressed like a bat universe: a group of people develop a sexual fetish surrounding accidental falls into vats of mutation-inducing toxic waste.That's cool. I was thinking, when the Joker gets his perma-grin from the acid wash, is there any way DC was using "mutation inducing" industrial waste as a veil for some lysergic counterpart? I figure this question probably betrays my ignorance, and I'm fine with that.
The Joker's original appearance is a bit too early for that, though I'm not sure about the red hood arc (i.e., his origin story). It's hard to tell how much of the really strange stuff in comics had its origin in legitimate psychedelia, since the comics code disallowed that sort of stuff. That said, the outfits that continued through the comics code era as comics were generally fairly conservative & straight-laced -- whereas the real freaks at EC shut down and started MAD.