Even in cities with good wastewater treatment systems, an emerging issue is the presence of man-made substances in our water supply. Increasing use of pharmaceuticals and personal care products has meant that chemicals or “contaminants of emerging concern” have been discovered in water with unknown effects for human and environmental health. An alarming find is intersex fish with both male and female characteristics in a growing number of streams in North America, Western Europe, and Japan immediately below the wastewater treatment plants. We do not know how these contaminants will affect people.