Florida fish are on an alarming number of prescription drugs, scientists discover

The findings came out of a three-year study of bonefish in Biscayne Bay and the Florida Keys

Seventeen different prescription drugs were discovered in a single fish in Florida during research into pharmaceutical contamination of marine species.

The findings came out of a three-year study of bonefish in Biscayne Bay and the Florida Keys by Florida International University (FIU) and the Bonefish & Tarpon Trust (BTT).

Researchers examined the blood and other tissues of 93 bonefish which typically swim in shallow, tropical coastal and island waters.

They found an average of seven pharmaceuticals per bonefish, and 17 pharmaceuticals in a single fish. The list of drugs includes blood pressure medications, antidepressants, prostate treatment medications, antibiotics, and pain relievers.

Medications were also found in the species that bonefish prey upon including crabs, shrimp and other fish, suggesting that more Florida marine species are exposed.

The pharmaceuticals end up in the ocean from human wastewater with contaminants insufficiently captured by water treatment plants.

Even at low doses, exposure to pharma drugs can impact fish behavior and be detrimental to their reproduction, migration and survival.

Lead researcher Jennifer Rehage, a coastal and fish ecologist and associate professor at the FIU Institute of Environment, called the findings “truly alarming”.

“Pharmaceuticals are an invisible threat, unlike algal blooms or turbid waters. Yet these results tell us that they are a formidable threat to our fisheries, and highlight the pressing need to address our longstanding wastewater infrastructure issues,” Prof Rehage said in a statement.

The researchers noted that while five billion prescriptions are filled each year in the US, there are no environmental regulations for disposal of these drugs worldwide.

And it isn’t only Florida fish that are being impacted by drugs. A study, published earlier this year in the academic journal PNAS, found pharmaceuticals present at over 25 per cent of testing sites along 258 rivers around the world, including the Amazon and the Thames.

A quarter of the sites had contaminants including the antibiotics, sulfamethoxazole and ciprofloxacin, and the allergy medicine loratadine.

Some of the active pharmaceutical ingredients most frequently detected at sites included the diabetes drug metformin, epilepsy medicine Carbamazepine, and caffeine.