Scientists say sharks off the coast of Brazil have tested positive for cocaine.
Marine biologists tested 13 Brazilian spearfish caught off the coast near Rio de Janeiro and found they had high levels of cocaine in their muscles and livers.
This concentration is up to 100 times higher than previously reported concentrations in other aquatic organisms.
The study, conducted by the Oswaldo Cruz Foundation, is the first to detect the presence of cocaine in sharks.
Experts believe cocaine is entering the water supply through illegal labs where the drug is produced or through the feces of drug users.
Cocaine packages lost or thrown into the sea by smugglers could also be a source, although this is less likely, the researchers said.
Sara Novais, a marine ecotoxicologist at the Centre for Marine and Environmental Sciences at the Polytechnic University of Leiria, told Science magazine that the findings were “very important and potentially worrying.”
All of the women in the study were pregnant, but experts say the consequences of cocaine exposure on the fetus are still unknown.
Further research is needed to determine whether cocaine alters shark behavior.
However, previous research has shown that The drug may have the same effect on animals as it does on humans.
Last year, chemical compounds including benzoylecgonine, which is produced by the liver after cocaine use, were found in seawater samples collected off the south coast of England.
