The National Environment Management Authority (Nema) has shut down three companies in Nairobi for investigations into reports of toxic emissions.
Powerex, Edible Oils and Usafiplus companies, located along Mombasa Road, were closed indefinitely on Wednesday.
The shutdown followed complaints by residents of emissions they said led to the hospitalisation of four children and left others with effects including nose bleeding, persistent coughs, vomiting and sore eyes.
Last Monday, Environment Cabinet Secretary Keriako Tobiko ordered immediate investigations into the persistent emission of toxic gases at night by some industries in the Nairobi South area.
On Wednesday, he said a report by the National Environmental Complaints Committee (NECC), led by its Secretary Dr John Chumo, necessitated further investigations.
"Yes, three companies have been closed to allow investigations. We want to keep tracking the process to make sure no company resumes operations without being given a clean bill of health," he said.
He added, "We are committed to the fight against pollution of any form. Stern action will be taken against those found culpable of polluting the environment and putting lives in danger."
Mr Tobiko directed Nema and the NECC to send a team to the organisations and present him with a preliminary report on the findings.
Two weeks ago, City Hall warned that the more than 20 factories in the area would be closed and their owners prosecuted over toxic emissions.
David Makori, Nairobi County's Environment Chief Officer, said two companies were adversely mentioned by residents.
Assembly majority whip and South B MCA Waithera Chege said a report on the closure of the companies will be tabled before the House next Tuesday, after ward representative return from their short recess.
"Following the closure, normalcy has resumed and I have not received any complaints from residents of more emissions. However, this is not the end of the investigations. We want those responsible to held accountable," she said.
Although specific reasons for the closure of Powerex and Edible Oils were not given, Usafiplus - a waste management company - was shut down for operating without a license following a site inspection by Nema.
Nema's report indicated that the company in industrial area was incinerating medical and industrial waste without a license and had not conducted an environmental audit since 2016.
The other reasons were that employees worked without protective gear, the lack of records of stock emissions or air quality assessment as well as records of incoming and incinerated waste.
"Based upon the findings, your facility should stop further operation until it meets standards and is licensed by Nema. The management should also report to Nema offices at Nyayo House with all the relevant documents," stated a report signed by Nema inspector Veronica Maina.