https://motherboard.vice.com/en_us/article/a3mzve/human-waste-is-contaminating-australian-wildlife-with-more-than-60-pharmaceuticals

Dozens of pharmaceutical drugs have been detected in aquatic Australian wildlife—a telltale sign that human medications are seeping into the environment from wastewater plants.

The insidious effects of prescription drugs on nature’s waterways are relatively understudied. But research has demonstrated that medications excreted in human urine, feces, and bathwater can migrate from sewers into oceans, rivers, lakes, and streams.