FWIW, I'm no doctor or scientist, but my dad was pre-diabetic and was doing injections in his belly to prevent him from becoming diabetic. The injections were not insulin, but rather something derived from Gila monster venom. I imagine it was synthesized, but I kind of doubt that they could just dump stuff like this into a city's water supply. The fact that people can use those self-tests to have tap water test positive just proves how lousy those junk tests are and how they are a waste of money.