“What we eat and what we excrete goes into the Puget Sound,” said Jennifer Lanksbury, a biologist at the WDFW.
Scientists deposit mussels in cages in 18 locations. They teamed up with the Puget Sound Institute to analyze the data and discovered that three locations were positive for trace amounts of oxycodone - two near Bremerton's shipyard and Elliot Bay near Harbor Island.
"It's telling me there's a lot of people taking oxycodone in the Puget Sound area. The contamination is likely coming from wastewater treatment plants," Lanksbury said.
After people consume oxycodone, some of it ends up in the toilet, and it 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.
And 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.
Again, Lanksbury says people have nothing to worry about when it comes to eating mussels from a restaurant or shop because they come from clean locations.
“They’re clean and healthy and delicious. We love to eat mussels from the Puget Sound. We use them for our food and we use them for contaminant analysis,” Lanksbury said.
But the study shows it's another sign of what's ending up in the water and harming marine life.
“People should be wary,” Lanksbury said. “Hopefully our data shows what’s out there and can get the process started for cleaning up our waters.”
This was a one-time study for prescription drugs, but Fish and Wildlife officials will seek more funding to continue testing and tracking what happening to in the water over time.