Antidepressants leaking into waterways could make crayfish bolder
Trace amounts of antidepressants washing into rivers and lakes could be making crayfish behave more boldly, and disturbing their ecosystems.
Evidence has been growing that various medications can end up in waterways because they are excreted in people’s urine. This includes antidepressants known as selective serotonin reuptake inhibitors (SSRIs), which are widely used to reduce depression and anxiety, with almost one in eight people taking them in the US.
In people, SSRIs raise levels of a brain-signalling chemical called serotonin, which is present in many animals including crayfish. Lindsey Reisinger at the University of Florida and her colleagues wondered if they would make crayfish less fearful, in the same way the drugs makes humans less anxious.