Scientists Say Sharks Are Testing Positive For Cocaine
Hello everyone! We’ve got an unusual and alarming discovery from the deep blue sea that’s worth talking about. Scientists have found traces of cocaine in wild sharks off the coast of Brazil. Yes, you heard that right—cocaine in sharks! This discovery is shedding light on the dangerous impacts of the illegal cocaine trade on marine life.
Between September 2021 and August 2023, Brazilian sharpnose sharks were captured by fishing fleets off the coast of Rio de Janeiro. Thirteen sharks—three male and ten female—were tested, and all of them showed positive results for cocaine. The findings were detailed in a study published in the journal Science of the Total Environment.
Researchers found cocaine and its major metabolite, benzoylecgonine, in the sharks’ muscle tissue and livers. This is the first time such a discovery has been made in wild sharks globally, marking a significant concern for marine biologists and environmentalists.
The exact source of the cocaine exposure remains a mystery, but scientists have a few theories. One possibility is that traces of cocaine entered the coastal waters through raw sewage discharged from rivers and urban canals. Another potential source could be cocaine packages drifting in the water, either lost or discarded by drug smugglers, which pose a risk if sharks bite into them.
This situation draws a parallel to the infamous “Cocaine Bear,” a 500-pound black bear in Georgia that overdosed on cocaine thought to have been thrown from a drug smuggler’s plane in 1985. The bear’s story was loosely adapted into a horror movie in 2023.
The presence of cocaine in sharks points to broader environmental issues. These findings suggest that illicit drugs in the marine environment could have significant impacts. Researchers are particularly concerned about the potential for cocaine to reenter the food chain, as these sharks are fished for their meat.
Previous studies have shown that illegal drugs and legal medications are accumulating in waters worldwide. In São Paulo state, for example, scientists have found that cocaine contamination poses an ecological threat to marine life, including mussels and oysters. Astonishingly, the level of cocaine in São Paulo’s waters has been compared to the concentration of caffeine in coffee and tea.
This problem isn’t confined to Brazil. In 2019, British researchers discovered freshwater shrimp were being exposed to cocaine and other pharmaceuticals in the country’s rivers. The United Nations has reported a significant increase in global cocaine consumption over recent decades, with Brazil being one of the largest consumers in South America.
The sharpnose shark was chosen for this study because of its small size and habitat, which is prone to significant contamination from sewage. This makes the shark an “environmental sentinel,” indicating the health of the marine ecosystem in contaminated areas.
Researchers found that cocaine levels were three times higher in the muscle tissue compared to the liver. Interestingly, female sharks had higher cocaine concentrations in their muscle tissue compared to males. The levels of cocaine and benzoylecgonine found in the sharks exceeded those reported in the literature for fish and other aquatic organisms by up to two orders of magnitude.