Kariokor Market, Baba Dogo, Donholm, Hazina Estate and parts of Gachie are among the areas with the most polluted air in Nairobi.
This is according to a five-day study by the United Nations Environmental Programme (Unep) of the air quality of major roads in August.
Unep’s chief scientist Jacqueline McGlade said these areas have a high concentration of poisonous gases that have adverse effects on humans and on the environment.
She said that the major pollutants in the city are vehicles.
This, she said, is as a result of incomplete combustion in car engines.
“The situation is worsened by traffic jams that concentrate the pollution in one area. Climate change and global warming are precipitating factors,” said Ms McGlade.
She said power plants, industries and households are also pollutants. Ms McGlade said if the fumes are inhaled, they cause respiratory diseases and even death over time.
“In a few months, a mobile phone application would be available to enable people to track the areas with the most pollution and avoid them for a day or two until the pollution subsides,” said Ms McGlade.
Interestingly, according to the study, Thika Super Highway is barely polluted.
The analysis was conducted by an equipment called the Unep Air Quality Monitoring Unit, which costs about Sh150,000, a figure the UN agency says is much cheaper than other existing kits.
Environment Cabinet Secretary Judi Wakhungu launched the gadget at the Unep headquarters in Gigiri, Nairobi yesterday.
“The device is timely as it will help map the city’s air pollution hotspots and inform governments to plan appropriately. We would like to establish as many as 50 more units with the assistance of Unep,” she said.
Prof Wakhungu said some of the devices could be based in learning institutions to form part of their regular weather monitoring lessons.
After the launch, journalists were taken on a bus ride and they were able to compare air pollution levels around the city in real time.
Preliminary results, collected by the mobile monitoring unit, show that large parts of the city may have unsafe levels of air pollution.
Achim Steiner, UN Under Secretary-General and Unep Executive Director said: “In Africa, 20 out of every 100,000 people die prematurely due to exposure to dangerous ambient air pollutants.”
The UN agency plans to make the blueprints of its device available to the public to allow governments and organisations to assemble units themselves.