As for how they should be destroyed or thrown out...is being debated. You might recall recently the E.P.A. did a test of major public water systems and found of all things strong trace levels of antibiotics.
Strong trace...? Unless one believes in homeopathy...then the less there is of a substance, the more powerful it is. Back in the real world... The term "trace" indicates minuscule amounts. The amounts in that latest EPA scare were exactly that, trace. The main thing the EPA was concerned about was the fish being altered by the presence of some of the compounds. Fish (and amphibians!) are far more sensitive to things in the water than us mammals. The EPA went out of their way to emphasize that this does not represent a danger to humans. Funny how that didn't make it to the headline...
Current recommendations are still to flush them down the toilet.