>> The necessary implication would be that waste from patients on certain drugs should be treated as hazardous, or even radioactive. That's pandora's box.

So here's the bit that I don't get. When my friend had to get her cat a medical scan, the cat had to have radiactive contrast ingested/injected. She was then told to carefully, without touching it, collect all poop made by the cat in the next 7 days, put it in this special container, then bring it back to the vet for safe disposal.

However, when humans have the same procedure done....no one cares? You drink radioactive contrast, then pee and poop as normal, it all goes down our drains. How does that make any sense?