By Nchetachi Chukwuajah
Residents of Kogi and Kebbi states risk health hazard from microbial and chemical contamination of their water sources.
This is according to the Nigeria Hydrological Services Agency (NiHSA) which said flooding has led to high concentrations of microbes, arsenic, and lead in water sources in the states.
The NiHSA said the toxic metals were discovered after the agency conducted a water quality assessment during flood evaluation exercises, which revealed contamination in some shallow wells caused by floodwater intrusion.
At a press briefing in Abuja on Thursday, October 16, the Director of Hydrogeophysics at NiHSA, Sunday Ushe, explained that there are high concentrations of microbes and arsenic in Kebbi State, while there are high concentrations of microbes and lead in Kogi State.
Ushe explained that floodwaters transported sediments and chemical residues from farmlands, mining areas, and open defecation sites into water bodies used for drinking and domestic purposes.
He said, “From our assessments, there are high concentrations of microbes and arsenic in Kebbi State, while there are high concentrations of microbes and lead in Kogi State in the water sources of the states.
“When there is flooding, water sources are usually inundated because flooding transports sediments from very far locations and these settle on water sources.
“The sediments contain microbes and heavy metals, which could originate from mining activities, agricultural practices, fertilisers, and herbicides applied on farms. These chemical elements also enter groundwater systems.
“The issue of microbes and pathogens also stems from sanitation problems—people defecate indiscriminately, animals also defecate, and these are transported by floodwaters and dumped into water systems. If it is groundwater, it is introduced into groundwater; if it is surface water, it remains there.
“According to the World Meteorological Organisation, with regard to microbial contaminants or pathogens, the permissible limit of those bacteria is supposed to be 0.00, meaning they should not exist at all in water.
“But from our analysis, we found samples with high concentrations of microbes or pathogens such as E. coli, total coliform, Salmonella typhi, and Streptococci. These are bacteria or pathogens that are not supposed to exist in the water system, yet we found higher concentrations of these microbes in the states.”
Ushe warned that contaminated water can cause diseases such as dysentery, diarrhoea, typhoid, and other gastrointestinal illnesses due to microbial pollution, adding that lead exposure can cause kidney damage and neuro-developmental disorders.
“We observed high concentrations of arsenic and microbes in Kebbi State’s water systems, and high concentrations of microbes and lead in Kogi State’s water systems.
“Meanwhile, the permissible limit of lead and arsenic set by the World Health Organisation and the Nigerian Standard for Drinking Water Quality is 0.01 milligramme per litre.
“But we found that in Kebbi State, arsenic concentrations range from one milligram to about four milligrams per litre, which is dangerous.
“If you consume water containing arsenic, it is toxic to health. It might not cause immediate harm, but over time, it targets organs like the kidneys, liver, and skin, and begins to damage them. It can cause liver and kidney damage, skin cancer, and bladder cancer, because the concentration exceeds the WHO-prescribed permissible limit.
“In Kogi State, lead concentrations range between 1.5 and about 12 milligrammes per litre, compared to the permissible limit of 0.01 milligramme per litre, according to the WHO and the Nigerian Standard for Drinking Water Quality,” he noted.
The Director-General and Chief Executive Officer of NiHSA, Umar Muhammed, called for stronger flood preparedness, improved sanitation practices, and tighter control of agricultural and mining runoff into rivers and groundwater systems.
Muhammed also called for greater collaboration among relevant ministries, humanitarian partners, and local authorities to ensure the provision of safe drinking water to affected communities.
