Residues in drinking water from antidepressants and other drugs that impact the central nervous system may have a link to autism, according to a new study involving fish. In an experiment conducted by researchers at the Idaho State University, minnows exposed to low levels of two selective serotonin reuptake inhibitor (SSRI) antidepressants (Prozac and Effexor), as well as the anti-epileptic medication, Tegretol, exhibited significant alterations in genes normally associated with autism in humans.
According to a report from NewScience.com, the use of antidepressants has increased dramatically over the past 25 years. A we’ve reported previously, SSRI antidepressants, including s Paxil, Prozac, Celexa, Lexapro, and Zoloft, are the most widely used medications to treat depression. A growing body of research has linked these medications to birth defects and other issues when they are used by pregnant women, especially in the early months of pregnancy when many women don’t realize they are pregnant.
Roughly 80% of the active ingredients found in the drugs studied by the Idaho State researchers pass straight through the human body without being broken down. As a result, low traces of the medications will be present in drinking water, as most communities’ are unable to filter them out. For this experiment, the Idaho State researchers exposed fathead minnows to the same low-levels of Prozac, Effexor, and Tegretol that are normally found in water. The fish were exposed to the drugs for 18 days, after which the genes being expressed in their brains were analyzed.
According to New Science, the research team expected genes involved in all kinds of neurological disorders to be impacted by exposure to the drug cocktail. But surprisingly, only 324 genes involved in early brain development and wiring were altered. In humans, those genes are associated with autism. The study, which is published in the journal PLoSOne, also found fish exposed to the drugs tended to panic and behave differently from a control group of fish.
The study doesn’t come close to proving that trace levels of SSRI antidepressants in drinking water cause autism. More research is needed, and the Idaho State scientists plan to study whether the drugs have a similar effect in mammals. However, this is not the first time research has linked the use of SSRI antidepressants to autism. In fact, last July a study published in Archives of General Psychiatry this past July, children born to mothers who took an SSRI in the year before pregnancy faced a two-fold increased risk of being diagnosed with an Autism Spectrum Disorder (ASD). The risk jumped to nearly four-field if an expectant mother took an SSRI antidepressant in the first trimester of pregnancy.