Researchers warn over harmful drug substances in FCT dam
Cyril Mbah, Abuja
A group of researchers studying the healthy condition of Usuma Dam, a primary source of water supply in the Federal Capital Territory (FCT), has warned against the high amounts of harmful drug substances and contaminants that are dangerous to health in the water.
The group said that pharmaceutical substances have become known as part of the emerging group of contaminants that pose serious risk to human life stressing that since the substances are potentially harmful to human and ecological health, the use of the items need to be regulated and routinely monitored by the government.
In a publication in a medical journal known as Conversation – an independent source views from the academic and research community, the researchers said, “We found traces of pharmaceuticals in the water and unexplainable sediment the Usuma dam and that is not good for ecological and public health.”
The group also listed the effects of the drugs on aquatic and human life to include DNA damage, disruptions to hormonal systems and formation of antibiotic resistant microbial strains.
According to the researchers, the solution to the dangerous environmental challenge should therefore be an urgent national response especially the close monitoring of operators of water treatment plants.
Usuma Dam was constructed about three decades ago and it is home to four water treatment plants that serve Abuja and its environs.
The publication was produced on behalf of the researchers by Ifenna Ilechukwu, lecturer of environmental chemistry, Madonna University, Nigeria.
The publication said, “ Pharmaceuticals, especially drugs used to prevent or treat human and animal diseases, are essential for health and well-being. But the increasing use of such drugs by water treatment plants means that remnants of the drugs are showing up in the aquatic environment and are contaminating our waters.
The publication said further that “Pharmaceuticals are part of a group of substances known as emerging contaminants. Although they are potentially harmful to human and ecological health, they are yet to be regulated and routinely monitored in the environment.
“Most conventional treatment plants typically do not remove emerging pollutants because they were not originally designed to do so. These contaminants can enter oceans, rivers, streams, dams and groundwater through waste water and sewage treatment plants, human excretion, landfill leaching, healthcare facilities, pharmaceutical industry effluents and veterinary drug applications.
“The contaminants may be transported in water to other places or accumulate in sediments in rocks, sand, soils, decaying materials and vegetation under water and in creatures that live in water.
“Some of the effects of these drugs on living organisms include DNA damage, disruptions to hormonal systems and formation of antibiotic resistant microbial strains.
“There have been several studies of pharmaceuticals in aquatic environments across the world but only a few studies in African countries. So, in our study, we investigated the occurrence of selected harmful pharmaceuticals in water and sediments of Usuma dam in Abuja, Nigeria’s capital. We also assessed the risk of the harm they could do.
“We found traces of pharmaceuticals in water and sediment of the dam and that is not good for ecological and public health. The dam is an important source of potable water and fish for people living in Abuja.
“It is also a major receiving water body, and acts as a sink for pollutants from the environs. It is surrounded by large unplanned settlements and is the major drain for household, municipal and agricultural wastes in the area.
“Our research investigated the occurrence of selected antibiotics and analgesics (painkillers) in water and sediments of Usuma dam. We looked for antibiotics in water samples and found amoxicillin, ciprofloxacin and metronidazole. Trimethoprim was also found in the sediment samples. These antibiotics are used to treat or prevent bacterial infections. “Ibuprofen, detected only in sediments, was the only painkiller detected in the study.
We found that amoxicillin and Ibuprofen presented a high risk to aquatic life in the dam. Ciprofloxacin constituted medium risk, while metronidazole constituted low risk.
The report added that although pharmaceuticals were designed to exert maximum effects at low concentration, any high concentration found in water and soil is not good for public and ecological health.
“If these drugs negatively affect the fishes in the dam through accumulation, they can also affect humans who eat them and drink water from the dam. Any consumption of drugs other than a prescribed dose for a particular ailment is a health risk.
“We observed that the chief source of pharmaceuticals in the dam is human excretion. Sewage from unplanned settlements that lack basic sanitation and sewage treatment facilities around the dam is disposed of directly onto the ground and eventually drains into the dam. Other likely sources include improper disposal of medical and veterinary waste.”
The report concluded that the occurrence of pharmaceuticals in the Usuma dam is not an isolated case in Nigeria. Similar studies have reported the presence of pharmaceuticals in Lagos and Ogun state waters and even in sachet water that many Nigerians drink adding that the solution to this budding environmental challenge should therefore be a national response.