Sharks off Brazil coast test positive for cocaine

Marine biologists have discovered that sharks off the coast of Brazil are testing positive for cocaine, the BB reported. Thirteen Brazilian sharpnose sharks captured near Rio de Janeiro were found to have high levels of cocaine in their muscles and livers. The concentrations detected were up to 100 times higher than those previously reported in other aquatic creatures.

This groundbreaking research, conducted by the Oswaldo Cruz Foundation, marks the first instance of cocaine being detected in sharks. Experts suggest that the drug is entering the ocean through illegal drug labs or via excrement from drug users. While there is a possibility that lost or dumped cocaine packages by traffickers contribute to this contamination, researchers consider this scenario less likely.

Sara Novais, a marine eco-toxicologist at the Marine and Environmental Sciences Centre of the Polytechnic University of Leiria, described the findings as “very important and potentially worrying.” All the female sharks in the study were pregnant, but the effects of cocaine exposure on their fetuses remain unknown.

Further research is necessary to determine whether cocaine exposure is altering the sharks’ behavior. Previous studies have indicated that drugs can have similar effects on animals as they do on humans.

This discovery follows a similar finding last year when chemical compounds, including benzoylecgonine—a byproduct of cocaine metabolism—were found in seawater samples off the south coast of England.