More than 300 students and teachers have reportedly been hospitalised following recurring incidents of unusual gaseous odour in parts of Ogun State between April and October 2026, raising concerns about the safety of schools and surrounding communities.
The incidents, reported mainly in Ijebu-Ode and neighbouring communities, caused students to faint, experience breathing difficulties and suffer other symptoms, prompting emergency medical responses and temporary school closures.
Although the state government has linked previous emissions to underground geological activity and detected methane in affected areas, investigations into the source of the recurring emissions have remained a major concern.
Here is a timeline of the incidents and the responses by authorities.
April 1: First reported incident
The first widely reported incident occurred on April 1 at Our Lady of Apostles Secondary School, Epe Garage, Ijebu-Ode.
The PUNCH reported that at least 30 students and one teacher were hospitalised after a gaseous substance spread across the school premises shortly after morning assembly.
Some students reportedly collapsed, vomited and experienced breathing difficulties, prompting the school to arrange emergency medical attention.
The affected persons were taken to the General Hospital, Ijebu-Ode, where they received treatment. The Commissioner for Environment, Ola Oresanya, said the exact substance responsible had yet to be established.
There were initial suggestions that the incident might have involved fumes from a school laboratory or another source in the surrounding community.
On April 2, the Ogun State Government ordered the closure of the school and directed security agencies to investigate the incident.
Governor Dapo Abiodun also ordered the establishment of a situation room at the General Hospital, Ijebu-Ode, to provide free treatment for affected students and residents of surrounding communities.
The PUNCH reported that all affected students were responding to treatment, with no death recorded.
May 15: Second incident affects more than 100
Less than two months later, another incident was reported in Ijebu-Ode on May 15, affecting students and teachers in several schools.
The PUNCH reported that more than 100 students and teachers were affected, with victims taken to the Ogun State Hospital, Ijebu-Ode, and private medical facilities.
The affected schools included Anglican Girls Grammar School, Obalende, and Our Lady of Apostles Secondary School, Epe Garage.
Witnesses said students complained of stomach aches, weakness and breathing difficulties, while some fainted and had to be assisted into vehicles for medical attention.
An eyewitness told The PUNCH that the situation was more serious than the first incident, adding that the hospital was crowded with affected students.
The state government subsequently said air-quality monitoring equipment had detected elevated methane concentrations in Ijebu-Ode, with peak readings of approximately 13,500 parts per million in surrounding locations.
The government said the readings were below the lower explosive limit but remained environmentally significant and required further investigation.
It also announced a multi-agency environmental and public health assessment involving relevant regulators, emergency responders and technical experts to determine the source and extent of the emissions.
On May 17, the Commissioner for Health, Tomi Coker, said all persons admitted to the State Hospital, Ijebu-Ode, following the incident had been discharged after receiving medical attention.
She said the patients included adults and children.
Coker explained that methane could displace oxygen in the body, potentially causing symptoms such as fatigue, rapid heartbeat and breathing difficulties, depending on the level of exposure.
The government also announced plans to strengthen emergency medical response in the area, including deploying ambulance crews and training teachers and interested parents as community first responders.
June 3: Third incident sends 69 students to hospital
Another episode was reported on June 3 at Our Lady of Apostles Secondary School, Ijebu-Ode, with students again experiencing symptoms after perceiving an unusual odour.
The PUNCH reported that 69 students were hospitalised following the incident.
The Commissioner for Health later confirmed that all 69 students had been discharged after receiving medical care.
According to the commissioner, most of the students were discharged on Wednesday, June 3, 2026, while the remaining seven who stayed overnight were discharged on Thursday after their conditions improved.
The incident was described as the third reported occurrence in the area within two months, renewing concerns among parents, teachers and residents about the cause of the recurring emissions and their possible health implications.
The Commissioner for Environment, Ola Oresanya, said government-installed gas analysers had detected methane in affected areas.
The schools identified in reports about the earlier incidents included Our Lady of Apostles Secondary School, Anglican Girls Grammar School, Titilayo Agbaje Comprehensive High School in Imosan, Ifesowapo Comprehensive High School in Imosan, and St Anthony Grammar School in the Ijebu-Imushin area, among others.
Following the repeated occurrences, the government announced plans to relocate students of the affected school temporarily while investigations continued.
By June, officials had begun advancing a possible geological explanation for the emissions.
The government said the gases could be escaping from underground through fractures associated with geological and tectonic fault lines. It ruled out sabotage and gas pipeline leaks as the cause of the earlier occurrences.
However, the explanation did not end concerns about the recurrence of the incidents.
October 21: Fresh emissions affect three communities
On October 21, another incident was reported across parts of Ijebu-Ode, Ijebu-Igbo and Ago-Iwoye, making it the fourth major reported episode of the recurring emissions since April.
The PUNCH reported that more than 100 students across several secondary schools were hospitalised after inhaling an offensive gaseous substance.
The affected schools included Anglican Girls Grammar School in Ijebu-Ode, Ijebu-Igbo Girls Grammar School and Itamerin Comprehensive High School in Ago-Iwoye, among others.
Students reportedly experienced shortness of breath, stomach disorders and drowsiness. Some fainted and were rushed to hospitals, while some required oxygen to stabilise their conditions.
The affected students were taken to the State Hospital, Ijebu-Ode, the General Hospital, Ijebu-Igbo, and other healthcare facilities.
The unusual odour also disrupted school activities in Ago-Iwoye, where some schools sent students home.
The incident extended beyond school premises. The chairman of Ijebu North Local Government Area reportedly detected the odour at the council secretariat, prompting further concerns about its spread into surrounding communities.
Responding to the development, the Ogun State Government said the situation was under control and that investigations had begun to establish the source and extent of the emissions.
Oresanya linked the latest occurrence to previous underground gas emissions reported in the Ijebu axis since April.
A team from the Nigerian Upstream Petroleum Regulatory Commission also joined the assessment and investigation.
However, the cause of the latest incident had yet to be conclusively established in the reports published on October 21.
Investigation yet to provide lasting answers
The recurring incidents have raised questions about the safety of students and residents in affected communities, particularly as the emissions have been reported at schools more than once.
In June, the Ogun State Government attributed the previous occurrences to a natural geological process involving underground gases escaping through fractures associated with geological and tectonic fault lines.
The government ruled out sabotage and gas pipeline leaks as explanations for those earlier incidents.
However, TheCable reported on October 21 that the investigation launched in June had still not been concluded as of September, after the publication contacted the Commissioner for Environment.
The latest episode has therefore renewed attention on the need to establish the source of the emissions, determine why they continue to recur and assess the potential health risks to people living, working and studying in the affected areas.
The outstanding questions include whether the emissions have a common source, what measures can prevent another occurrence and how the government will ensure that schools and surrounding communities remain safe.