Americans aren't the only mammals being afflicted by the illegal drug trade as traces of fentanyl have been found in bottlenose dolphins in the Gulf of Mexico.

Several researchers at Texas A&M University-Corpus Christi found traces of the deadly narcotic in a dead dolphin floating in the water while conducting a routine boating survey in September 2020, KRIS-TV reported Thursday.

The researchers took the dolphin back to their lab; and two years later, when doing a hormone blubber analysis on the carcass, they came across the drug.

"It's not something we were looking for, so of course we were alarmed to find something like fentanyl, especially with the fentanyl crisis happening in the world right now," Makayla Guinn, a doctoral student studying stress physiology in bottlenose dolphins, told KRIS. "These drugs and pharmaceuticals are entering our water, and they have cascading effects in our marine life."

Guinn and marine biologist Dr. Dara Orbach were co-authors of a study called "Pharmaceuticals in the Blubber of Live Free-Swimming Common Bottlenose Dolphins" published Nov. 29 by iScience.

Guinn said there were more than 3,000 compounds inside the dolphin blubber, including several pharmaceutical drugs such as sedatives and relaxants. At least 89 dolphin blubber samples were analyzed for the study, including 83 collected through live dolphin biopsies and six from dead dolphins from Texas and Mississippi.

Pharmaceuticals were found in 30 of those samples. Fentanyl was found in all six of the dead dolphins, according to the publication.

Orbach said it's possible the drugs reached the dolphins through wastewater, but there are other possibilities.

"It's likely they're getting these pharmaceuticals in their system from eating prey," she told KRIS. "Those prey being the same fish and shrimp that we're also eating over here, considering that the Coastal Bend is such an important fishing community, locally."

Orbach said the discovery could lead to more research to trace the source of the fentanyl and limit potential damage to the ecosystem.

"Some of these samples we looked at are more than a decade old and those animals also had pharmaceuticals," she said. "So we think this is a longstanding problem that no one's been looking at."

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