At least 100 students and teachers were hospitalised on Friday, May 15, following an exposure to a suspected chemical odour in some schools in Ijebu-Ode, Ogun State.
The schools reportedly affected include Anglican Girls Grammar School, Obalende, and Our Lady of Apostles Secondary School, Epe Garage.
According to reports, some students complained of stomach aches, weakness and breathing difficulties after inhaling the substance.
The affected students were rushed to the State Hospital, Ijebu-Ode, and some were taken to private medical facilities for treatment.
The Ogun Commissioner for Environment, Ola Oresanya, confirmed the incident, saying relevant agencies had commenced necessary interventions.
Mr Oresanya said the ministry of education, ministry of environment, security agencies, and local government authorities were jointly handling the situation.
In a statement issued on Friday, the commissioner said an Air Quality Monitoring Device installed at Ijebu Ode Grammar School detected elevated methane concentrations.
He explained that the device recorded methane concentrations of about 13,500 parts per million (ppm) in surrounding areas.
Mr Oresanya said the methane concentration remained below the lower explosive limit but required immediate technical investigation and precautionary measures.
He said the state government would activate a multi-agency environmental and public health assessment team to investigate the incident.
He added that the team would determine the emission source, assess exposure risks and evaluate other associated gases in the environment.
The commissioner advised residents to remain calm and go about their normal activities while avoiding open flames near areas with unusual gas odours.
He also urged residents experiencing dizziness, headaches, nausea or respiratory discomfort to seek immediate medical attention.
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