So, just how "hazardous" can a tank full of poo be?

These examples escape me! :h

I never see any contact with black tank contents. I hook up stinky slinky, drain black, galley, then grey. It is all clean when I disconnect. I do wear rubber gloves during the process, and all the Stinky stuff in a 5" vinyl fence post under the 5er.

If their stuff is that bad they should not be dumping at a public dump.