SEATTLE (KIRO/CNN) - When people take drugs like opioids, that's not the end of the story.
They excrete those drugs back into wastewater, and a group of researchers found some marine life absorbing those chemicals and testing positive.
The Washington Department of Fish and Wildlife brought in clean mussels from Whigby Island and put them in the water at Elliott Bay by Harbor Island to test the water for pollution.
There's enough opioids in Elliott Bay for mussels to register for that when they're put in the water.
Scientists have discovered oxycodone in mussels when testing water for contamination.
"What we eat and what we excrete goes into the Puget Sound," said Jennifer Lanksbury, Washington Dept. of Fish and Wildlife."So these are Penn Cove mussels. These are the mussels we use in our analyses."
They deposited mussels into 18 locations. Three of locations came back positive for oxycodone, two near Bremerton and Elliot Bay.
"It's telling me there's a lot of people taking oxycodone in the Puget Sound area. It's likely coming from wastewater treatment plants," Lanksbury said.
After people consume oxycodone, some of it ends up in the toilet and goes into wastewater.
The water gets filtered, but King County Wastewater Management said although their system can catch a lot of contaminants, it can't specifically filter out drugs.
Opioids, antibiotics, drugs for depression - mussels are testing positive for all of it.
"Those are definitely chemicals that are out there in the nearshore waters, and they may be having an impact on the fish and shellfish that live there," Lanksbury said.
People have nothing to worry about when it comes to eating mussels from a restaurant or shop because they come from clean locations., but it's another sign of what's ending up in the water and harming marine life.
Fish and Wildlife said testing mussels for prescription drugs was a one-time study, but it will look for more funding to see what's happening to the water over time.
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