Mussels test positive for opioids and chemo drugs

bowl of mussels
CC BY 2.0 Marco Verch

Over the course of three months, previously clean mussels picked up a slew of contaminants from the waters of Puget Sound.

The opioid crisis that has killed thousands of people in the U.S. and Canada in recent years is now affecting wildlife. Researchers at the Washington State Department of Fish and Wildlife have discovered traces of oxycodone and other medications in mussels taken from Puget Sound in Washington state. Lead study biologist Jennifer Lanksbury said,

“We found antibiotics, we found antidepressants, chemotherapy drugs, heart medications and also oxycodone."

Mussels are filter feeders, meaning they strain out nutrients and plankton from the water to eat; but unfortunately in this day and age, that also means a dose of pollution. These drugs enter the water by way of human excretion and when people flush pills down the toilet. Wastewater management systems are unable to filter out drugs effectively.

The Puget Sound Institute says the oxycodone was found in amounts "thousands of times lower than a therapeutic dose for humans and would not be expected to affect the mussels, which likely don’t metabolize the drug." But a spokesman for the Institute, Andy James, said, "You wouldn’t want to collect (and eat) mussels from these urban bays."

The study was conducted by moving cages of clean mussels from an aquaculture center and placing them near 18 urbanized locations around Puget Sound. Several months later volunteers collected the mussels and tested them for contaminants. Of the 18 sites, three tested positive for oxycodone -- not a huge number, but enough to cause concern. Lanksbury told Global News:

“It seems like the prescriptions for opioids are high enough that it’s starting to come out in the waters here at least in the really you know, dense urban corridors."

Chemotherapy drug Melphalan was also found, known as a potential carcinogen for its interaction with DNA. From the Puget Sound Institute:

"The drug was found at 'levels where we might want to look at biological impacts,' said [Andy] James. The mussels had ingested amounts of Melphalan relative by weight to a recommended dose for humans."

While the tested mussels were said to be far from commercial shellfish beds, we know that pollution spreads far and wide throughout the ocean. Other research from British Columbia last year found that bivalves contain an average of 8 plastic microfibres each (courtesy of synthetic clothes being laundered), and scientists at the University of Ghent estimated that the average Belgian enjoying mussels and other seafood on a regular basis ingests 11,000 pieces of plastic each year.

Add in a pharmaceutical cocktail and suddenly this nutritious, ethical source of seafood is looking less and less appetizing.

Related Content on Treehugger.com