Just a few months after cocaine was detected in the bodies of sharks off the coast of South America, research has found fentanyl and other drugs in dozens of dolphins in the Gulf of Mexico, adding to a growing record of pharmaceuticals infiltrating our marine environments.

Of 89 dolphins tested in the Gulf of Mexico, 30 contained some form of pharmaceutical—and 18 had fentanyl in their blubber.

Traces of other pharmaceuticals, including muscle relaxants and sedatives, were also found in blubber samples.

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.

The opioid fentanyl has made its presence known in an unexpected place — the blubber of dolphins in the Gulf of Mexico. In a concerning study, researchers detected fentanyl in 27% of analyzed dolphins,