Scientists discover cocaine in sharks off the coast of Brazil

The only thing worse than a cocaine bear might just be a cocaine shark. Scientists in Brazil said they discovered traces of cocaine in 13 sharks living off the coast of Rio de Janeiro.

Cocaine was found in all of the sharks’ liver and muscle tissue, with the amount being three times higher in the muscle, according to the research published in the journal Science of the Total Environment . Female sharks had higher cocaine concentrations in their muscle tissue than the males that were tested.

Some of the female sharks tested were also pregnant, but the effects of cocaine on the shark fetuses are unknown.

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The sharks used in the study were Brazilian sharpnose sharks, chosen by the researchers at the Oswaldo Cruz Foundation because of their small size and where they live.

The scientists believe the cocaine entered the aquatic system through a chain of pollution. The drug can make its way out to sea through raw sewage from people who use it as well as runoff from the illegal labs that produce it, one of the study’s co-authors told CNN .

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It’s not yet clear what physiological or psychological effects the cocaine may have had on the sharks, but other research has shown the drug impacts animals similarly to humans.

While it's not the first research to discover the presence of cocaine in marine animals, it is believed to be the first study to find cocaine in sharks from a natural habitat.