No, not a play on words — would that I wre that clever. (I long ago gave up trying to be clever in poetry because so many others do it so much better. One has to play to one’s strengths.)

“Stool sample” is just an inherently funny expression. I’d be very surprised if other poets haven’t played with that, too.

Mushrooms are odd. For centuries we’ve thought of them as plants, but now they have their own kingdom and are recognized as being closer to Animalia. They was the poisonous ones dissolve the human liver is terrifying.