Just remember Every person in your city produces on average 100 gallons of waste water a day multiply that by the people in your city and that is alot of water to Dilute the chemicals.... Wastewater plants run test to check for harmful chemicals.... Grease cause a wastewater Nightmare so think of that next time you pour it down the drain along with hot water..... :OT
You Might check with your local waste water officials at the waste water plant and they will certianly be able to tell you if it is harmful.... They say that effluent waste water (Ie Clean waste water for reuse) is typically cleaner that water taken in by clean water plants to make potable water.... In other words it is suppose to be safe to drink.... But I wouldnt try it