Why anyone ever thought that was a good idea is beyond me, but dozens of scientific studies have found remnants of our medications in rivers, lakes and streams.
The buildup of prescription drugs in the environment is mainly due to the fact that our bodies don't process all of the ingredients, so they often enter the water system when we go to the bathroom. But flushing the meds directly can add to the buildup, too.
Birth control pills in the water system have been linked to feminizing fish, antidepressant meds have been found concentrated in fish brains, and antibiotics can kill aquatic organisms like algae.
"Medications that are flushed down the toilet or thrown straight into the garbage can and do find their way into our nation's waterways every day," Sam D. Hamilton, Southeastern Regional Director of the US Fish and Wildlife Service, said in a press release. "Those drugs are present in water that supports many species of fish and other wildlife. We are concerned about reports of fish abnormalities possibly caused by improperly disposed prescription medications."
So how should you dispose of your leftover or expired medications?
The best option, according to the US Food and Drug Administration, is to bring them to a community take-back program. Many police stations and pharmacies are designated drop-off sites. You can use these tools to find law enforcement agencies or pharmacies that will dispose of medication near you.
If you can't find one of those, you legally can dispose of medicines in the trash. But the FDA recommends first combining them with an undesirable substance like coffee grounds or kitty litter so children or pets don't eat them, putting them in a plastic bag to prevent leakage, and destroying your name on prescription drug containers to protect your identity.
But throwing medications away should really be a last resort, for the environment's sake.