Wild Dolphins Test Positive for Fentanyl, Suggesting Drugs Are Flooding the Ocean

Bottlenose dolphins are swimming in drugs, including fentanyl, according to a team of researchers that recently examined 89 blubber samples from the iconic cetaceans.

The team’s study—set to publish in iScience—reveals the extent to which pharmaceutical contaminants have spread in American waterways and affect one of the most popular species of marine mammal.

The team found fentanyl, as well as the drugs carisoprodol and meprobamate, both used pharmaceutically for pain relief, in 30 of the 89 dolphins they studied, which were recovered from sites in Texas and Mississippi.

Though simply touching or being near fentanyl is not deadly—despite the persistent myth, which is sometimes parroted by law enforcement—fentanyl is responsible for hundreds of thousands of fatal drug overdoses in the United States. In case it must be said plainly: fentanyl is not a good thing for dolphins to have in their systems.

The opioid is 100 times more potent than morphine and can be fatal if not used in a controlled environment. The Gulf of Mexico is not a controlled environment, and dolphins are “effective bioindicators of ecosystem health in contaminant research,” according to the paper. Which is to say, there’s a good chance that fentanyl is affecting other organisms in the Gulf of Mexico, too.

Fentanyl was found in “substantially more” blubber samples than the carisoprodol and meprobamate, which the team noted “is expected as fentanyl readily distributes to fat.” 63% of the tissue samples were from male dolphins and the remaining 37% were from female dolphins; twelve of the samples were collected from the Mississippi sound in 2013, showing the issue has persisted along the gulf coast and dates back at least a decade.

“As 40% of all detected pharmaceuticals were found in the historical samples, pharmaceutical pollution may be a long-standing issue that has been largely overlooked,” the study authors wrote. “Assessment of historic water and tissue samples across marine taxa for pharmaceutical detection will provide insights into the duration of the issue.”

Shockingly, the dolphins aren’t the first sea creature to make headlines for human drugs in their system this year. Over the summer, sharks off the coast of Rio de Janeiro tested positive for cocaine, an indicator that trace amounts of abused human drugs are affecting all kinds of creatures that never signed up to take them.