Dolphins are becoming hooked on a deadly opioid pumped into the sea in waste water.
And drug smugglers could also be dumping packages of powerful synthetic painkiller fentanyl into the Gulf of Mexico and Mississippi Sound to avoid capture by coastguards or federal US agents.
Scientists have found the opioid in the bodies of more than 20 per cent of bottlenose dolphins tested in the waters, which are often used to smuggle drugs from Mexico to America.
The marine mammals are thought to have ingested fentanyl after eating fish. As this food is also consumed by humans there are fears this could add to the opioid addiction epidemic gripping the US, which led to an estimated 74,702 deaths last year.
Dr Dara Orbach, an assistant professor of marine biology at Texas A&M University, said: “Dolphins eat the same fish and seafood that we do so, if they are uptaking pharmaceuticals through fish and seafood consumption, we may be as well.”
The shocking findings, published in the US journal iScience, follow last year’s documentary Cocaine Sharks, which revealed traces of the drug were found in 13 sharpnose sharks off the coasts of Florida and Brazil.
It is thought likely the sharks devoured packages of cocaine either lost or dumped into the water by smugglers.
But sewage being discharged into the sea is seen as a more likely cause of the fentanyl being ingested by dolphins.
Researcher Makayla Guinn said: “These drugs and pharmaceuticals are entering our water and are having cascading effects on our marine life.”
