Just as the police bang down the door, the bad guys flush the incriminating drugs down the toilet. Surely, a scenario we've all seen on TV and in the movies. But, you might be surprised to find out how many drugs innocently wind up in our lakes and rivers every day.
Household drugs like painkillers, antibiotics and hormones enter the water system through many channels. For example, some animal feeds contain antibiotics and flood into rivers with run-off water. Antibiotics are regularly flushed or dumped down sinks and toilets. Since many sewage treatment plants don't effectively remove drugs or hormones, these compounds enter our waterways and wind up in our tap water.
Are flushed drugs a health concern? Once in a river, antibiotics might affect wildlife by killing off the normal microbes that are naturally found in the water and soil and that form the basis of the local ecosystem. Or, perhaps more dangerously, the microbes may learn to adapt and reproduce in the presence of antibiotics, developing antibiotic resistance.
At present, common household drugs are found in many lakes and rivers in relatively small concentrations, but we can do something to help. We can avoid throwing drugs down the drain and, instead, take them to a hospital, pharmacy or hazardous waste center for safe disposal.
"Common Drugs Cloud Rivers" (Chicago Tribune)
"Pharmaceuticals and Personal Care Products in the Environment: Overarching Issues and Overview" (EPA)