Cocaine trafficking is a scourge for Latin American countries – now also across the oceans. Scientists have discovered that sharks in Brazil have tested positive for the drug.
Marine biologists tested 13 Brazilian sharks they spotted near Rio de Janeiro and found very high levels of cocaine in their muscles and livers. The concentrations were up to 100 times higher than previously reported for other aquatic creatures.
How Cocaine Ends Up in Sharks
The research, conducted by the Oswaldo Cruz Foundation, is the first to detect the presence of cocaine in sharks. Experts believe that cocaine enters the waters through waste from illegal laboratories where the drug is produced or through the feces of drug users.
Packages of cocaine lost or thrown overboard by traffickers could also be a source, although this is less likely, researchers say.
Sara Novais, a marine ecotoxicologist at the Center for Marine and Environmental Sciences at the Polytechnic University of Leiria, told Science magazine that the findings are “very important and potentially worrying.”
All of the female sharks in the study were pregnant, but the effects of cocaine exposure on their fetuses are currently unknown, experts say.
The possible effects
More research is needed to determine whether cocaine alters shark behavior. However, previous research has shown that the drugs likely have similar effects on animals and humans.
Last year, chemicals including benzoylecgonine, produced by the liver after cocaine use, were found in seawater samples taken off the south coast of England.