Common medications that billions of people take for ailments like pain, fever and infections were detected in several sites along Djibouti’s Gulf of Tadjourah in East Africa, according to a recent study.
Researchers found that untreated urban wastewater contained dangerous concentrations of anti-inflammatory medicine like ibuprofen, caffeine, and the antiepileptic drug carbamazepine, which were contaminating Djibouti’s coastal ecosystem. They also detected the presence of levofloxacin, an anti-tuberculosis antibiotic, and 12 other pharmaceutical and personal care compounds.
The Gulf of Tadjourah is an important marine biodiversity hotspot that is home to coral reefs, mangroves and fish nurseries. Djibouti City, home to more than 70% of the country’s population, borders the gulf.
“One particularly surprising finding was the relatively high ecological risk associated with some common everyday pharmaceuticals, especially ibuprofen and caffeine,” lead author of the study Abdillahi Elmi Adaneh, an environmental chemist at the regional Observatory for Research on the Environment and Climate (ORREC) in Djibouti, told Mongabay by email.
“These compounds are often perceived as ‘ordinary’ substances, yet they were among the main contributors to ecological risk in the coastal waters we studied,” he added.
Ibuprofen was among the most concerning substances detected, Adaneh said. At one sampling site, where urban and hospital wastewater are dumped in the water, the team found ibuprofen concentrations hundreds of times higher than levels considered safe for aquatic organisms.
“[Ibuprofen] can disrupt several biological functions in marine organisms, including reproduction, growth, enzymatic activity, and physiological responses,” Adaneh said. “Invertebrates, fish, and algae are particularly sensitive to non-steroidal anti-inflammatory drugs.”
Researchers wrote that caffeine, which was detected in all the sampling sites, is widely used as an indicator of pollution from domestic wastewater. They also noted the combined effects of these contaminants are even more concerning than their individual effects.
The study is one of the few of its kind to be carried out in East Africa. However, pollution from medicines has been a growing concern globally, especially as many of these compounds can have long-lasting effects in marine organisms. A global study published in 2022 found evidence of pharmaceutical pollution even in remote locations like Antarctica.
Researchers highlighted wastewater treatment as a solution to preventing pharmaceutical pollution in marine environments; according to the U.N., just 11% of domestic wastewater is treated in Djibouti.
In Marseille, a city on the southern coast of France, species like neptune grass (Posidonia oceanica) and salema porgy (Sarpa salpa) were able to bounce back after the city introduced a wastewater treatment plant in 1987.
“Discharges of untreated urban and hospital wastewater are turning Djibouti’s coastal waters into a chemical cocktail that poses a high ecological risk,” Adaneh said. “It is a problem that makes Djibouti a cautionary tale for many low- and middle-income countries.”
Banner image: From left to right, Tannwir Sagid Abdoul-Bari, Ismael Said Ismael, Mahamoud Ali Chirdon and Abdillah Elmi Adaneh collect water samples in Djibouti. Image courtesy of Abdillah Elmi Adaneh.
