‘Cocaine sharks’ throng Brazilian waters as drug enters ecosystem

A sharpnose sevengill shark, closely
related to the Brazilian sharpnose - Kelvin Aitken/Alamy

Cocaine has been found in sharks off the coast of Brazil and may be changing their behaviour, scientists fear. 

Marine biologists tested 13 sharks of the “Brazilian sharpnose” type taken from coastal waters near Rio de Janeiro and found they all had high levels of cocaine in their muscles and livers. 

In a paper for the journal Science of the Total Environment, they said the drug probably originated in drainage from illicit labs where cocaine is manufactured, or from the excrement of drug users, via untreated sewage.

It might even have come from the sharks feeding on bales of cocaine that were lost or dumped overboard by drug smugglers – but that was less likely, the team said.

By Nick Squires.

Full story at Yahoo News.