From anxiety medication to birth control, pain killers, nutrient supplements and blood thinners, the remains of what we put into our bodies pass through the other end, off to the waste control centers that need to deal with our mess. Getting pharmaceutical leftovers out of the water so that it can be safely passed back into the environment is a costly and tricky task, and conventional waste water treatment techniques aren’t up to the task.
The introduction of drug remnants to the environment has even been found to affect the behavior of fish, says Smithsonian‘s Surprising Science blog:
Over the past decade, researchers have repeatedly discovered high levels of many drug molecules in lakes and streams near wastewater treatment plants, and found evidence that rainbow trout and other fish subjected to these levels could absorb dangerous amounts of the medications over time. Now, a study published today in Science finds a link between behavior-modifying drugs and the actual behavior of fish for the first time. A group of researchers from Umeå University in Sweden found that levels of the anti-anxiety drug oxazepam commonly found in Swedish streams cause wild perch to act differently, becoming more anti-social, eating faster and showing less fear of unknown parts of their environment.