Cocaine Sharks Found in Brazil

We’ve all heard or even seen the movie Cocaine Bear but have you heard of cocaine sharks? Scientists in Brazil are shocked when they discovered that the 13 sharks they tested for coke all came back positive! They have never previously tested for cocaine in sharks so we don’t know how long this has been going on.

According to the research in Science of the Total Environment sharks are ingesting Cocaine and other very harmful chemicals. Co-author of the research Rachel Ann Hauser-Davis says that no one has ever studied the effects of cocaine in sharks. She goes on to say that this is not the only thing concerning.  “We detected high levels of metals and also detected ‘forever chemicals’ [perfluoroalkyl and polyfluoroalkyl substances, or PFASs], pesticides and polycyclic aromatic hydrocarbons, PCBs and PBDEs in over 30 shark and ray species.” PCBs were banned in America in 1976 because they are known to cause brain development and hormonal issues. What does this mean for our shark friends in the ocean?

Enrico Mendes Saggioro, an ecotoxicologist and co-author, became interested in this study after testing river water contaminants in Rio de Janeiro. He discovered cocaine in the water and wanted to know how this affected the sharks. The results were shocking.

Cocaine Sharks Results

The research team tested sharpnose sharks which dwell in Rio de Janeiro. They found that they all contained 23 micrograms per kilogram of cocaine in their tissue. The research also showed that male sharks have lower concentrations of cocaine. Half of the female sharks that they caught were also pregnant. What this means for their offspring is undetermined. Mendes Saggioro plans to continue the research and expand the testing to rays and migratory fish.

Brazil has over one million Cocaine users who live in areas without any sewage treatments. This means that the cocaine-contaminated urine goes directly into the shark-dwelling waters. Another way drugs get into the ocean and the shark’s system is by being dumped. Those who fear being caught by authorities might dump it in the water.

The director of the Shark Lab at California State University, Chris Lowe, is not surprised by the results. The biologist said, “to think that you wouldn’t find cocaine or other illegal drugs in sharks is kind of crazy.” David Shiffman, a marine conservation biologist at Arizona State University, is concerned for the sharks. His message, “Please don’t dump your trash, including illegal drugs, into the water.”