KCSE candidates and teachers fall ill after exposure to lethal chemical

Monday November 11 2019

A KCSE candidate conducts an experiment during a Chemistry practicals exam on October 17, 2014. FILE PHOTO | DENISH OCHIENG' | NATION MEDIA GROUP


Scores of Form Four candidates and invigilators have been taken ill following exposure to a suspected deadly chemical used during the chemistry practical exam last Friday.

Education ministry and the Kenya National Examination Council (Knec) are on the spot for exposing the examiners and candidates to xylene—a highly toxic chemical compound known to cause health complications, and even death.

In Trans Nzoia, an expectant teacher is admitted to Galilee hospital after developing complications linked to the exposure.

Ms Cherusha Nyakeri, a teacher at St Monica Girls Kitale, was rushed to the hospital after being exposed to fumes that emanated from heating xylene at Gidea Girls School in Kwanza.

The Nation has learnt that Knec directed headteachers to buy and use the poisonous chemical as an alternative for the cyclohexane, which was unavailable in the market.



A student from St Peters Kajulu Secondary, a mixed day school, was admitted to Kombewa Sub-County Hospital on Friday after the chemical exploded on her face.

The candidate sustained serious burns.

Kisumu County Kuppet Executive Secretary Zablon Awange said that other schools, including Kasagam Secondary and St Theresa Girls witnessed the toxic gas explosion.

“We're demanding a ministerial statement on the use of xylene as a reagent in the chemistry practicals. Xylene is a poisonous gas that can cause adverse health complications not only on the students, but also on teachers,” Mr Awange said.

He told the Education ministry to compensate all those affected.

“We have asked our teachers to go for medical check-ups. We don't know why the Kenya National Examinations Council chose to replace cyclohexane with xylene. We demand an explanation,” Mr Awange said.


During the practical text, candidates were supposed to heat the chemical and observe the flame produced, without protective wear.

It was not immediately clear if officials at the ministry were aware of the adverse health effects of the compound, also know as xylol or dimethylbenzene.

Several supervisors and invigilators who were exposed to the fumes in Nyeri, Embu and Meru counties reportedly fell ill after the exam.

A teacher from Nyeri, who requested anonymity due to the sensitivity of the incident, said he had been sickly since Friday.

The fumes, he said, were very strong and sooty, and made him dizzy and nauseated.

“I was in the room with the students for two hours and when the students burned the chemical it produced a lot of soot and since then, I've been feeling sick and dizzy,” he said.

The students were exposed to the toxic fumes for two hours, while some invigilators were exposed for up to six hours.


Some schools in the Eastern region were forced to give the candidates milk to neutralise the effects of the toxins during the chemical reaction.

Some are said to have been admitted to hospital for the better part of the weekend. They were later discharged.

“We had to rush some of the students to hospital after the exam because they were complaining of chest pains, headaches and stomach discomfort. We gave milk to the rest,” another teacher from Embu said.

Exposure to xylene vapours in small amounts causes headache, dizziness, drowsiness, and nausea.

In some cases, it is known to damage the central nervous system. The effects are usually felt within two-to-three minutes of inhalation.

Prolonged exposure to xylene can cause sleepiness, irregular heartbeat, fainting, or even death.


Knec, which directed teachers to buy the hazardous chemical, is yet to respond to Nation queries on the incident.

Acting CEO Mercy Karogo said she was engaged in meetings when contacted by the Nation on Monday.

But Trans Nzoia TSC director Odipo Okumu said they are waiting for a doctor’s report.

“She is currently in stable condition and there is no cause for alarm since there is no other reported case. We are, therefore, treating this as an isolated case,” Mr Odipo told the Nation.

An attempt to get a medical report from the Kitale hospital proved futile as the management of the private facility denied journalists entry on grounds that they were protecting the patient’s privacy.

Meanwhile, teachers in Trans Nzoia have accused Knec of negligence.

“Knec should not just be concerned about the integrity of the examination and overlook the health of the teachers who are manning the examination. Our lives matter,” Trans Nzoia Kuppet chairman Furaha Lusweti said.