It seems that fish in America’s Great Lakes don’t have to worry about dealing with depression. A recent study of ten different species in the Lakes have found significant levels of antidepressant drugs in their brains. Though this may sound somewhat funny, it is actually a serious problem.
Millions of Americans take these medications every day to treat anxiety and depression. Small amounts of the drugs end up being excreted into toilets and flushed away as wastewater. The wastewater treatment plants are not able to completely remove the medications from the water, and they wind up in America’s rivers and lakes, where fish consume them.
Rather than simply lifting the moods of fish, these medications present an existential threat to them. Previous research has shown that shrimp can become suicidal when exposed to antidepressants. These shrimp swim toward the light instead of away from it, making them more vulnerable to predators.
No shrimp were studied in this latest batch of research involving Great Lakes species, but the medications can have similarly bad effects of the fish that were tested. These drugs can cause fish to become lethargic to the point that they are no longer interested in hunting or breeding. They can also cause fish to ignore the presence of predators, leading to them becoming prey more often than they should. This could have a devastating impact on biodiversity in the Lakes.
Fortunately, the levels of the antidepressants found in the fish are not high enough to pose a danger to humans. So, it is still safe to eat fish from the Great Lakes for now, especially since the drugs are concentrated in organs that people don’t eat, such as the brains of the fish. There is a real threat to the fish living there, though, and to other animals in the ecosystem that depend on them. In addition, the region’s multimillion dollar fishing industry could be severely affected by a reduction of species.
Since more and more people start taking these important medications every year, it is clear that something needs to be done to get them out of the water. Scientists say that new methods of water decontamination need to be developed that are capable of removing antidepressants from wastewater. Currently, treatment plants don’t even screen water for the presence of these drugs, so that would be a good starting point. But the researchers point out that nothing is likely to be done until the government mandates that a solution be found. Until then, medications excreted by humans will continue to find their way to our freshwater systems, and ultimately to our fish.