In a surprising discovery, researchers have found that more than a dozen sharks off the coast of Brazil have cocaine in their systems. Scientists from the Oswaldo Cruz Foundation reported that 13 Brazilian sharpnose sharks had cocaine in their muscle tissue and liver. This discovery, reported by CNN, is the first instance of cocaine being found in wild sharks.
The sharks were chosen for the study because they are small and live in coastal waters near significant contaminant sources. The study found that cocaine levels in these sharks were up to 100 times higher than those found in other marine animals. Notably, female sharks had higher concentrations of cocaine in their muscle tissue than males.
The researchers believe that the rise in global cocaine use is a major factor in this contamination. South America is home to about 22% of the world’s cocaine users, with Brazil being a significant consumer market. The study suggests that increased drug use and poor sewage treatment are more likely causes of the cocaine contamination than drug traffickers dumping cocaine. Enrico Mendes Saggioro, one of the study’s authors, noted that unlike Mexico and Florida, Brazil doesn’t frequently see cocaine bales dumped at sea.
The effects of cocaine on shark health are still unknown, as no specific studies have been conducted on sharks. However, previous research on fish and mussels shows that cocaine can be harmful. Mendes Saggioro and co-author Rachel Ann Hauser Davis mentioned that it is likely, although not yet proven, that cocaine exposure could negatively affect sharks.
Marine eco-toxicologist Sara Novais from the Marine and Environmental Sciences Centre highlighted the importance of these findings, describing them as “very important and potentially worrying.” The study underscores the environmental consequences of human drug use and the need for improved sewage treatment infrastructure to prevent such contamination.
