A recent study in aquatic toxicology studied the effects of several well prescribed anti-depressants on the behavior of shrimp. One in particular, fluoxetine, better known as Prozac significantly altered the shrimp’s behavior, causing them to move towards rather than away from light right into the awaiting maws of predatory shrimp-eaters. In scientist speak, this movement towards or away from light stimulus is called “phototaxis” (on a complete aside, another more bizarre photo-response is the photic sneeze effect where bright light causes someone to automatically sneeze. I like the mental picture of a mass of little sneezing shrimp…).
These kinds of studies are gaining more import because of the types of chemicals ending up in aquatic systems. Much of what we put into our bodies is never completely absorbed and ends up in the sewer system which consequently often ends up in other water-based ecological systems (sewage is treated for things like excess nutrients but we couldn’t possibly screen for all the possible chemicals sewage may contain). So materials like caffeine, medications we take, etc. are now outside of our superficial human realm and in the larger natural environment, with detrimental if not even bizarre effects on wildlife including sex changes in fish.
To find out more, read the sciencedaily feature here.