Over a four-day period last summer, Dustin Pack set out into Tampa Bay in search of one of the most coveted fish species in Florida.
Armed with fishing rods, live bait and his shallow-water skiff, it would seem like any other week for Pack, a full-time fly fishing guide and captain.
But during those blazing hot days in August, Pack wasn’t fishing for redfish just for the thrill.
He was fishing for science.
Pack was recruited to hook redfish for a new statewide study, released this week, which examined the species’ blood for 94 commonly prescribed pharmaceuticals. With Pack’s help, a researcher at Florida International University caught 15 redfish around Tampa Bay, in areas ranging from the northern Hillsborough Bay to the bay’s southern mouth at Emerson Point.
Now the results are public: All 15 fish in Tampa Bay had drugs in their blood.
Specifically, every redfish had a heart medicine called Tambocor in its system, according to the study published in partnership with the Bonefish & Tarpon Trust, a Miami-based conservation organization. The pharmaceutical is prescribed to treat irregular heartbeats.
“This is something that everyday people, and even fishing guides like myself, wouldn’t think of: Drugs in our redfish? It being so potent in our waterways that it’s strong enough to show up in blood tests? It’s kind of overwhelming,” Pack said.
Across the nine Florida estuaries examined for the study, Tampa Bay and Apalachicola had the highest number of pharmaceutical detections, according to the research. Redfish throughout Florida have an average of two different drugs in their blood. In Tampa Bay, that number is three.
“The medications that we take end up in our waters,” said Jennifer Rehage, a lead author on the study and a fish ecologist at Florida International University. “It’s another way of thinking about how connected we are to Tampa Bay.”
It wasn’t just heart meds found in local fish: Nearly 90% of Tampa Bay redfish had Tramadol, a heavy-duty opioid pain reliever, in their blood and tissue, according to the research.
Two out of every five redfish were also contaminated with psychoactive drugs that treat depression and schizophrenia. Some fish even had caffeine contamination.
“In an urbanized estuary like Tampa Bay, it is not at all surprising to me that pharmaceuticals were found in locally-caught redfish,” said Maya Burke, the Tampa Bay Estuary Program’s assistant director.
“Studies like this underscore the need for communities to invest in 21st century wastewater treatment technologies that remove not only bacteria and nutrient pollution, but a whole host of other contaminants.”
It’s a problem statewide
The research found redfish from Florida’s Gulf Coast to the Atlantic had drugs in their blood. Of the 113 redfish sampled throughout the estuaries, all but seven contained pharmaceuticals, according to Rehage.
Researchers detected 17 pharmaceuticals, with heart medicine, opioids and psychoactive drugs being the most common, according to the research. Seven of those drugs are documented to be harmful for fish, including caffeine and certain pain relievers.
“This makes us aware that the medications that we take can be damaging once they get out into the environment,” Rehage said.
While the drug concentrations found in each fish were small (you would have to eat roughly 48,000 fillets to reach a prescription dosage) it’s noteworthy that even trace levels were detected, Rehage said.
What that can do to a human body over long periods of time remains to be seen.
“Nobody knows what being exposed to something at really low levels over your lifetime means to your health,” Rehage said. “You’re getting exposed with some tiny, tiny levels of something for a long time, and it’s interacting with other pharmaceuticals.”
What can you do to help?
The science around drugs in Florida’s fish species continues to expand. This latest redfish study follows a similar research project, also led by Rehage, that examined bonefish in Biscayne Bay and the Florida Keys. During that study, scientists discovered 100% of the bonefish contained pharmaceutical contaminants.
Both studies are currently in the peer-review process, Rehage said.
In a statement, Bonefish & Tarpon Trust CEO Jim McDuffie said the latest research underscores the urgent need to modernize Florida’s wastewater treatment systems.
“Human-based contaminants like these pose a significant threat to Florida’s recreational fishery, which has an annual economic impact of $13.9 billion and directly supports more than 120,000 jobs,” McDuffie said.
Millions of gallons of treated wastewater enter Tampa Bay each day. Between 2016 and 2019, for instance, an average of more than 53 million gallons was released per day into Tampa Bay from the Howard F. Curren treatment plant, according to University of South Florida researchers.
The redfish study is “just another alarm for why we need to reinvest in our infrastructure here in Tampa Bay,” said Justin Tramble, the executive director of Tampa Bay Waterkeeper.
“In a place that’s supposed to be pristine, there are drugs in our fish.”
On an individual level, the public can help by supporting improvements to wastewater treatment plants and being more mindful about what you flush down the toilet, Rehage said.
“We can be really careful about how we dispose of our medications,” she said. “Don’t flush your medications and try to dispose of them responsibly.”
