Sharks in Bahamian waters have been found with traces of cocaine and caffeine in their systems.

 

A recent investigation published in the journal Environmental Pollution revealed that sharks in the Bahamas are testing positive for various substances, including caffeine, painkillers, and, in one instance, cocaine, which is attributed to human-induced marine pollution.

Researchers examined blood samples from 85 sharks belonging to five distinct species (lemon, Atlantic nurse, blacktip, Caribbean reef, and tiger sharks) near Eleuthera Island. Approximately one-third (28) of the sharks exhibited detectable levels of different drugs in their systems.

  Substances Detected:

  Caffeine emerged as the most frequently identified substance.

  Painkillers, particularly acetaminophen (Tylenol) and diclofenac (Voltaren), were also found.

  One shark tested positive for cocaine.

These substances are thought to enter the ocean mainly through human wastewater, sewage discharge, coastal urban development, and tourism activities. In the case of cocaine, researchers hypothesize that a shark may have bitten into a discarded package of the drug that had fallen into the water.

  The study observed alterations in metabolic markers in the affected sharks, indicating possible effects on their stress response and energy utilization. It remains unclear whether these changes are detrimental or will influence the sharks' behavior in the long term, although research on other fish indicates that stimulants like caffeine can modify movement and feeding patterns.

  The results underscore the extensive reach of human chemical pollution, affecting even remote marine ecosystems that are generally regarded as pristine. This study is the first to document the presence of caffeine and acetaminophen in any shark species globally, as well as the first report of diclofenac and cocaine in sharks from the Bahamas.