Water lines and winterizing

I blew out the water lines with 40 psi air pressure and added RV anti freeze to the p-traps and black and grey water tanks. I do not add antifreeze to the fresh water tank or the water lines, I don't want even biodegradable antifreeze in the tank or lines I may drink out of and I don't care if they say it is safe. Even biodegradable soap will contaminate the ground if it is dumped in the same place often enough.