More Than A Dozen Sharks Test Positive For Cocaine

 More than a dozen sharks living off the coast of Brazil tested positive for cocaine, researchers shared in a report on Tuesday.

A total of 13 Brazilian sharpnose sharks were tested by scientists who discovered the cocaine in both the muscle tissue and liver of the sharks, according to researchers from the Oswaldo Cruz Foundation in Brazil, CNN reported.

The sharks were chosen both because of their small size and that they live in the coastal waters that are in close proximity to a significant contaminant discharge for their entire life cycle, according to the report. It is the first time the drug has ever been detected in free range sharks, the outlet noted.

The study found that the cocaine levels in the 13 sharks had a concentration as much as 100 times higher than previously reported for other aquatic creatures, the study found.

And the cocaine concentration in muscle tissue was higher in female sharks than in their male counterparts. 

Researchers believe the rise in cocaine consumption around the world is most likely the cause, as around 22% of users of the drug users live in South America, with Brazil the second largest consumer market in the area, the paper found.

The report found that the increased consumption and poor sewage treatment infrastructure was the likely cause for the increased cocaine in the sea, rather than it being due to cocaine being dumped by traffickers, as previously suggested, study co-author Enrico Mendes Saggioro, an ecotoxicologist at the foundation, told CNN.

“We don’t usually see many bales of coke dumped or lost at sea here, unlike what is reported in Mexico and Florida,” Mendes Saggioro said, noting that the sea gets polluted by cocaine due to illegal laboratories producing the drug and along with the sewage discharges from humans users.

It is unclear at this point what kind of damage the cocaine may have done to the shark’s health, as studies have yet to be done. However, previous research on how the drug affects fish and mussels showed that it was harmful.

“It is probable, although not yet proven that exposure would have deleterious physiological effects on the sharks,” a joint statement from Mendes Saggioro and study co-author Rachel Ann Hauser Davis from the foundation, read.

Marine eco-toxicologist Sara Novais, from the Marine and Environmental Sciences Centre of the Polytechnic University of Leiria, called the findings “very important and potentially worrying,” Science magazine noted.