Fentanyl Detected in Gulf of Mexico Dolphins

The effects of the opioid epidemic may not be limited to humans, with dolphins found to have fentanyl in their systems. A large proportion of bottlenose dolphins in the Gulf of Mexico were found to have human pharmaceuticals in their bodies, including fentanyl, muscle relaxants and sedatives, according to a study published in the journal iScience. The dolphins are thought to have accumulated these drugs from eating fish and shrimp, which we also consume, suggesting that there could be risks to human health from environmental pharmaceuticals. "Since dolphins do not usually drink water, contaminants in the water are often consumed through prey, although there is a possibility of absorption through skin or inhalation. There are many potential sources of pharmaceuticals in the ocean including untreated wastewater," study co-author Dara Orbach, an assistant professor of marine biology at Texas A&M University-Corpus Christi, told Newsweek.

In their study, Orbach and colleagues sampled blubber tissue from 89 dolphins around the Gulf of Mexico and Mississippi Sound, six of which had been found dead. They discovered that 30 of the dolphins contained some form of pharmaceutical in their bodies, and 18 of the dolphins had fentanyl in their systems. All six of the dead dolphins were found to contain fentanyl. Fentanyl is a synthetic opioid that is 50 to 100 times more potent than morphine, according to the CDC. This high makes it effective for managing severe pain but also increases the risk of overdose. Synthetic opioids—mainly fentanyl—were involved in 68 percent of all overdose deaths across the U.S. in 2022, with the rate of overdose deaths involving synthetic opioids nearly 24 times the rate in 2013. The other pharmaceuticals found in the dolphins included carisoprodol—a skeletal muscle relaxant—and the anxiety medication meprobamate. "The amount of fentanyl we detected in the dolphins was very small, although we do not know how much would be deadly. Most pharmaceuticals were found in dolphins in regions of extensive human-caused stressors like dredging, chemical pollution, vessel traffic, and noise. Stressors can have cumulative effects and compromise dolphin immune response and survival," Orbach said. The presence of these drugs in the dolphins' bodies is concerning, as they are a good indicator of the general health of an ecosystem at large. "Dolphins are often used as bioindicators of ecosystem health in contaminant research due to their lipid-rich blubber that can store contaminants and be sampled relatively minimally invasively in live animals," Orbach said in a statement. "We did find one dead dolphin in Baffin Bay in South Texas within one year of the largest liquid fentanyl drug bust in US history in the adjacent county. And the Mississippi dolphins comprised 40 percent of our total pharmaceutical detections, which leads us to believe this is a long-standing issue in the marine environment." Interestingly, the researchers found higher levels of the pharmaceuticals in dolphins that lived in areas with other risks, including oil spills, vessel traffic and algal blooms. This study, Orbach concluded, "emphasizes the need for proactive monitoring of emerging contaminants, especially in regions with large human populations and major fishing or aquaculture industries." "We need to do additional research across the marine food web to understand the extent of pharmaceutical contamination in marine life, including fish and seafood. Dolphins eat the same fish and seafood that we do, so, if they are uptaking pharmaceutical through fish/seafood consumption, we may be as well," Orbach said. Do you have a tip on a science story that Newsweek should be covering? Do you have a question about opioids? Let us know via science@newsweek.com. Update 12/11/2024 12:50 p.m. This story has been updated with comments from Dara Orbach.

References

Ocampos, A. I., Guinn, M. A., Elliott, J., Wittmaack, C., Sinclair, C., Abdulla, H., & Orbach, D. N. (2024). Pharmaceuticals in the Blubber of Live Free-Swimming Common Bottlenose Dolphins (Tursiops truncatus). iScience, 111507. https://doi.org/10.1016/j.isci.2024.111507