The growing problem of pharmaceutical pollution threatens to affect the health and behavior of marine animals.
Traces of medicines for human use and illicit drugs were detected in sharks that live in the waters of the Bahamas. The conclusions are from one published in the journal Environmental Pollution, led by biologist Natascha Wosnick.
The researchers analyzed blood samples from 85 sharks near Eleuthera Island and found that nearly a third contained detectable levels of various substances, including caffeine, common painkillers and even cocaine.
Species affected included nurse sharks, Caribbean reef sharks and a juvenile lemon shark. THE caffeine was the most frequently detected compound, followed by over-the-counter medicationssuch as ibuprofen, paracetamol and diclofenac, refers to .
Scientists say contamination is largely the result of human activity, mainly through wastewater disposalsewage disposal and tourism. Even routine behaviors, such as swimmers entering the ocean after taking medications, can contribute to the accumulation of traces of chemical substances in marine environments.
A cocaine detectionalthough limited to a single case, highlights another route of pollution. Investigators suggest that the shark may have found drug packages discarded or lost at sea by drug trafficking networks.
Although the concentrations found were low, the potential biological effects are worrying. Sharks with contaminated blood showed changes in metabolic markers associated with stress and energy regulation. Although the long-term consequences remain uncertain, previous research on other marine species suggests that exposure to substances such as caffeine can alter behavior, including feeding patterns, movement and responses to threats.
Experts warn that this type of pollution is particularly insidious because it is largely invisible. Unlike plastic waste or oil spills, pharmaceutical contamination is not easily visiblebut it can still disrupt marine ecosystems in subtle but significant ways.
Researchers say further investigation is needed to determine the extent of the phenomenon and what it means for marine life and human health.
