'Cocaine sharks' have been confirmed to be swimming off the coast of Brazil

You read that right... scientists have found that multiple sharks off the coast of Brazil have tested for high levels of cocaine in their system.

The Oswaldo Cruz Foundation recently tested 13 Brazilian sharpnose sharks taken from near the shores of Rio de Janeiro as part of ongoing research, and were disturbed with their discovery.

The concentrations of cocaine found in the unfortunate shark's muscles and livers were estimated to be as much as 100 times higher than previously reported for other aquatic creatures in the area.

Experts have begun rattling their brains for what is the cause of this increase. It might not have to be said... but sharpnose sharks do not naturally produce cocaine in their bodies.

A Brazilian sharpnose shark. (Smithsonian Tropical Research Institute)

The Oswaldo Cruz Foundation are the first to find presence of cocaine in sharks in this area.

So, how did the class A drug get into the shark's systems?

Well experts believe there are quite a few ways it could be finding its way into the unsuspecting animals.

One possibility is that it is entering the waters via illegal labs, where the drug is being manufactured. It is also possible that it is getting into the water through the excrement of drug users.

Some have suggested that packs of cocaine lost or dumped by traffickers could be the cause, but researchers have said this is less likely.

British scientist and member of the research team from the Oswaldo Cruz Foundation in Rio de Janeiro Dr Rachel Ann Hauser-Davis told the Telegraph: “We don’t usually see many bales of coke dumped or lost at sea here, unlike in Mexico and Florida.

Researchers believe illegal labs producing cocaine may be responsible.(Getty Stock Image)

Interestingly, all the females that were recovered were found to be pregnant, but researchers are not completely sure of the consequences of cocaine on fetuses.

Sara Novais, a marine eco-toxicologist at the Marine and Environmental Sciences Centre of the Polytechnic University of Leiria, has said the finding are ‘potentially worrying’ but the discovery is also very important.

Dr Enrico Mendes Saggioro, an ecotoxicologist from the Oswaldo Cruz Institute, said it was important for scientists to continue studying the effects of cocaine on animals.

He said: "This may be the case, as cocaine targets the brain, and hyperactive and erratic behaviour has been noted in other animals. It’s a possibility and further studies are required."