Antidepressants in Our Water Make Crayfish Go Buck Wild - Gizmodo

A study published Wednesday in Ecosphere inspects the effects of selective serotonin reuptake inhibitors, or SSRIs, on crayfish, finding that the medication that helps people with depression actually makes crayfish act more “boldly” when added in small amounts to their environment.

“When you take a medication, nobody’s body is 100% efficient, so when we take a pill, we might only metabolize and actually use 90%, or 80%, or 70%,” said AJ Reisinger, an assistant professor at the University of Florida’s Soil and Water Sciences Department and lead author of the study.

Most pharmaceuticals in our water stay at pretty low levels; Reisinger said there’s been lots of previous work on the concentration of drugs needed to kill plants and animals, which is a lot higher than the concentration we see in the environment.

“People are often not concerned [about pharmaceuticals in the water] because of that,” Reisinger said.

Since SSRIs work to make serotonin more available to the brain, testing how SSRI levels in the water affect crayfish was an interesting question for researchers.

To figure out how these medications in the water affect crayfish, researchers recreated a crayfish’s natural habitat: an artificial stream, complete with leaves and rocks that had been left in real streams for a few weeks.

After two weeks of letting the crayfish settle in (and letting some of them absorb that sweet, sweet antidepressant water), researchers performed a behavioral experiment: they constructed a Y-shaped plexiglass maze, with one branch of the Y filled with chemicals that signaled food and the other filled with chemicals to signal the presence of another crayfish.