From Clif High and very accurate. There would need to be 1 million planets worth of poisonous snakes to poison the worlds tap water. If you milked every poisonous snake on the planet, you might have enough for NYC

He did say it was synthetic though. So maybe they're making it in a lab but still it not be enough to go in the water supplies all over the country. But they could use in in some areas...or in some of the vials.