Cocaine in the Ocean? Researchers Find Shocking Levels in Brazilian Sharks

Marine biologists have found high levels of cocaine in sharks caught off the coast of Brazil.

BBC reported that researchers from the Oswaldo Cruz Foundation in Brazil published a paper in the international journal Science of the Total Environment, revealing that all 13 Brazilian sharpnose sharks caught in the waters off Rio de Janeiro tested positive for high concentrations of cocaine in their livers and muscles.

The researchers chose Brazilian sharpnose sharks because they are small and live their entire lives in coastal areas exposed to pollutants.

While all the captured sharks showed traces of cocaine, the female sharks had higher levels of the drug in their muscles compared to the males.

Although chemicals such as benzoylecgonine, which is produced in the liver after cocaine use, were previously detected in sea samples from southern England last year, this is the first time cocaine has been confirmed in sharks. Notably, the concentration of cocaine found in these sharks was up to 100 times higher than previously reported in other aquatic organisms, surprising the researchers.

South America is a hub of the global drug trade, consuming 22% of the world’s cocaine. Brazil is the second-largest cocaine market in South America.

Cocaine could have directly entered the sea through lost or discarded drug shipments. However, it is more likely that water used in illegal cocaine manufacturing or excretions from drug users entered waterways.

The research team suggests that the presence of cocaine in sharks indicates rising cocaine consumption and highlights the pollution of ocean waters stemming from inadequate sewage treatment infrastructure.

Experts note that further research is required to understand the effects of cocaine on sharks, but previous studies suggest that drugs may impact animals similarly to humans.

Given that high concentrations of cocaine were found in pregnant female sharks, the researchers emphasized the need to investigate the potential effects of cocaine on fetal development in animals, similar to those observed in humans.