I seems like this thread sums up a lot of preconceived notions. Science is our friend. Superstition and a narrow mind is not.
When you drink fluids, do they not go through a chemical conversion and filtering before it exits the body? It is, as has been said lots of times in thread, essentially sterile.
Why would what a plant absorbs and use be any different? Plants have a conversion and filtering system as well. Do you really think that if you pee on your plants, then whatever you eat or smell off that plant is pee?
Going by that reasoning, don't ever put animal manure on plants because you're going to eat shit later...