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Trace Elements of Psychiatric Drugs Alter Fish Behavior

A new study raises concern about medication flushed into rivers and streams.

Four years ago, in September 2009, psychiatrist Peter D. Kramer, author of the bestseller Listening to Prozac, published a speculative article in Double X that asked: “Would putting the [tranquilizer Lithium] in drinking water make the brain healthier—but affect personality?”

Kramer’s article, which built on an editorial in the British Journal of Psychiatry, pondered the effects on the depressed of adding Lithium to everyone’s drinking water, but had much less to say about consequences for public health (much less the broader medical ethics) of giving small doses of the powerful tranquilizer to the vast majority of people who neither want nor need such medication. He also bypassed the side effects of even trace elements of the drug, including allergic reactions, blurred vision, involuntary twitching, vomiting and persistent nausea, seizures, slurred speech, and irregular heartbeat.

Kramer’s and the BJP's suggestion fortunately went nowhere, but last Thursday the journal Science published a study that made news for its findings about the behavioral effects of psychiatric drugs on fish when even small doses of the medication are flushed into rivers and streams.

“Researchers in Sweden,” reported Pam Belluck for the New York Times, “exposed wild European perch to water with different concentrations of Oxazepam, an anti-anxiety medication that can show up in waterways after being flushed, excreted or discarded. Researchers reported that fish exposed to Oxazepam became less social, more active and ate faster, behaviors they said could have long-term consequences for aquatic ecosystems.”

Oxazepam is an anxiolytic benzodiazepine—see here and here for other reports on the consequences and risks of this class of medication on humans.

The article in Science, “Dilute Concentrations of a Psychiatric Drug Alter Behavior of Fish from Natural Populations,” is, incidentally, much more emphatic and a lot less speculative than the New York Times preview implies. “Environmental pollution by pharmaceuticals is increasingly recognized as a major threat to aquatic ecosystems worldwide,” the authors write.

“Here we show that a benzodiazepine anxiolytic drug (oxazepam) alters behavior and feeding rate of wild European perch (Perca fluviatilis) at concentrations encountered in effluent-influenced surface waters. Individuals exposed to water with dilute drug concentrations (1.8 micrograms liter–1) exhibited increased activity, reduced sociality, and higher feeding rate. As such, our results show that anxiolytic drugs in surface waters alter animal behaviors that are known to have ecological and evolutionary consequences.”

More details here.

If psychiatric medication is having this effect on fish in their natural habitat, what is it doing to children, a population on whom it has not been formally tested? Follow me on Twitter @christophlane