This is evaprotive cooling tech. These things have existed for 1000s of years. They are called zeer pots.

The water evaporates through the outter clay pot and the latent heat of vaporization causes the water to cool drastically. Same exact principle as an air-conditioning unit, but it’s not a closed system, so you have to add more water. And waters energy from vaporization isn’t as good as a refrigerant. And it’ll only work well in a dry environment.

I’ve got an education in Chem E, and biomolecular engineering. And Im an engineer in the hyrdo-carbon polymer (plastic/rubber) business. He’ll be no worse then all of us really.

I personally wouldn’t recommend using printed pla for anything food related. But if you want to be realistic , if you 3d print, you have this stuff in your body through cross-contamination consumption and your lungs from mass transfer. (If you can smell a chemical, it’s in your blood stream)

In the grand scheme of things, the dude will be fine.