SEATTLE (KIRO / CNN) – When people take drugs like opioids, that's not the end of the story.
They divert these drugs back into the sewage, and a group of researchers found a marine species that absorbs these chemicals and tests positive
The Washington Department of Fish and Wildlife brought clean shells from Whigby Island and put them in the Elliott Bay at Harbor Island into the water to test the water for pollution.
In Elliott Bay, there are enough opioids for clams to register for when they are put into the water.
Scientists have discovered oxycodone in shellfish when testing water for contamination.
"What we eat and what we excrete go into the Puget Sound," said Jennifer Lankbury, Washington Department of Fish and Wildlife. "So these are Penn Cove shells, these are the shells we use in our analyzes."
They deposited shells in 1
"It tells me that many people take oxycodone in the Puget Sound area, it's probably from wastewater treatment plants," Lanksbury said.  After people have consumed oxycodone, some of them end up in the toilet and go into the sewage.
The water is filtered, but King County Wastewater Management said that although its system can trap many contaminants, it can not filter it out specifically
Opioids, antibiotics, depression medications – shellfish are tested positive.
"These are definitely chemicals that are out in coastal waters, and they can affect the fish shells that live there," Lanksbury said.
People have nothing to fear when it comes to eating mussels from a restaurant or shop because they come from clean places. But it's another sign of what lands in the water.
Fish and Wildlife said test mussels for prescription drugs was a one-time study, but it will look for more funding for what happens to the water over time.
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