In the U.S., more than 200 million prescriptions for antidepressants are given out every year. A lot of the contents of those pills eventually end up in our water supply, either from patients’ excretions or from pills flushed down the toilet. Since water treatment plants aren’t designed to remove pharmaceuticals, we’re effectively medicating our streams and rivers.
Chemists have found that water downstream of water treatment plants holds a veritable medicine cabinet worth of antidepressants, including venlafaxine, bupropion (Wellbutrin), citalopram (Celexa), fluoxetine (Prozac) and sertraline (Zoloft).
The concentrations of antidepressants in the water—billionths of a gram per liter—aren’t enough to affect larger species, but they are enough to make small fish and fish babies feel woozy. Researcher Meghan McGee tested the effect of antidepressants on young minnows by exposing unhatched and newly-hatched minnows to levels of antidepressants commonly found downstream of water treatment plants. The drugged minnows appeared lethargic and took twice as long to react to stimulus, making them much more vulnerable to predators. [Via]
Move up the food chain, and you have the bigger fish too reeling under the attack of our medications.