Sharks high in cocaine, caffeine and common painkillers have been discovered in the waters surrounding the Bahamas. This discovery by Brazilian scientists indicates high levels of pharmaceutical pollution and illicit drugs even in relatively remote marine ecosystems. The findings, published in the journal Environmental Pollution, are based on blood samples collected from 85 sharks near Eleuthera. Of these, 28 individuals from three species tested positive for various substances, the New York Post reported, citing the research. “Illicit drugs and drugs are increasingly recognized as contaminants of emerging concern (CECs) in marine environments, especially in areas experiencing rapid urbanization and tourism-driven development,” the researchers wrote.
Caffeine was the most common compound, followed by acetaminophen and diclofenac, the main ingredients in widely used pain relievers such as Tylenol and Voltaren. Two sharks also tested positive for cocaine, which researchers believe may have entered the water through discarded or lost drug packages. “They bite things to investigate and end up exposed,” study author Natasha Vosnick of the Federal University of Paraná in Brazil told Science News.
This study represents the first time cocaine has been discovered in sharks in the Bahamas, and the first recorded case of caffeine being found in sharks anywhere in the world. The researchers noted that many of the sharks sampled were located near popular tourist sites and diving sites, indicating pollution from sewage associated with boating and coastal development. The presence of these materials in such an area highlights the extent of human-caused pollution. While the behavioral impact on sharks remains unclear, scientists have observed changes in metabolic markers in contaminated individuals, indicating physiological stress. According to oceanographer Tracy Fanara, who was not involved in the study, this suggests that animals may be using more energy to process these pollutants. “We’re talking about a very remote island in the Bahamas,” Vosnick noted. Ultimately, this pervasive effect of drugs serves as a “reminder that coastal infrastructure, tourism and marine food webs are inextricably linked,” Fanara said.
