Cities in Africa are growing rapidly, but many countries lack effective technologies to measure associated air pollution. Experts are looking for new ways to monitor air quality in hopes of reducing health risks.
Yaoundé, the capital of Cameroon, vibrates with the rumble of engines. Smoke from cars and factories mixes with smoke from burning garbage and covers the city in a brown haze.
“With urbanization and economic growth, air pollution in urban areas has become higher, which makes people more prone to diseases associated with this polluted air,” Felix Assah, a member of the population health research group at the University of Yaoundé, told DW. , Such diseases include cancer as well as cardiovascular and respiratory diseases.
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Experts and organizations working for clean air in Africa recently met in Yaounde to discuss how they can collaborate to monitor air quality using sensor technology.
innovative technology
So far, measurement has been expensive, but progress has been made, said DO Okure, an air quality scientist at Makerere University in Kenya. Together with fellow researchers, Okure developed a local air monitoring system in 2015 that is inexpensive but effective. One advantage, Okure said, is that the system can be powered from a variety of energy sources. “At the same time,” he said, “instead of needing Wi-Fi, we are able to transmit data via GSM or SIM cards which are used in all parts of Africa.”
Although the technology provides important data, it is inadequate, Okure said, because it cannot yet clearly identify the sources of air pollution.
In Yaoundé, another project has installed equipment that monitors air quality in real time. Despite technical limitations, Asso Ngono Stephany of Cameroon’s national meteorological department hopes it will make it easier to track the dust. “Having measurement instruments on site is very valuable because we will be able to accurately follow what is happening over time as it relates to different dust concentrations in the atmosphere,” he said.
Yaoundé is the 10th African city to use this technology to monitor air quality, with more than 200 monitoring devices installed across the continent. The data also serves as the basis for political decisions to reduce pollution.
highly polluted and underrepresented
Some organizations warn that measurement capabilities are lagging behind urbanization. Africa is underrepresented in studies because data is either insufficient or not collected at all. This is also the case with the World Air Quality Report from IQAir, a Swiss technology company that specializes in air quality monitoring and developing air purification products.
The report includes data from measurement stations in 134 countries and territories in 2023. But the authors say the report does not represent 34% of Africa’s population due to a lack of publicly available data on air quality. Countries such as Chad and Sudan were not included at all.
The report refers to PM2.5 values, or fine dust particles no larger than 2.5 micrometres in diameter – roughly equivalent to the thickness of a spider’s web. The World Health Organization recommends that these particles should not exceed an average of 5 micrograms per cubic meter of air per year.
The report found that Africa’s most polluted cities are eight to 11 times this value. These include capital cities such as Kinshasa, Democratic Republic of Congo; Cairo, Egypt; Abuja.Nigeria; and Ouagadougou, Burkina Faso). Two South African cities top the list: the capital, Bloemfontein, and the coal-mining town of Benoni.
data sparks transformation
Another new report from international environmental protection organization Greenpeace found that Egypt, Nigeria and South Africa are the most polluted countries in Africa when it comes to industrial and economic sectors, including the fossil fuel industry.
Data from satellites and even fuel sales in individual countries made it possible to investigate the source of emissions. Cynthia Moyo, climate and energy campaign manager for Greenpeace Africa in Johannesburg, told DW: “We found that air pollution monitoring satellites regularly track thermal power plants, cement plants, metal smelters, industrial areas and urban areas along the way.” “Aligned emissions find hotspots.” “Six of the world’s 10 largest nitrogen dioxide emissions hotspots and two of the 10 largest sulfur dioxide emissions hotspots are in South Africa.”
Areas like Mpumalanga in the east of the country, where burning coal to generate electricity is a major industry, are particularly exposed, Moyo said. According to Greenpeace, Eskom, a public utility whose sole shareholder is the South African government, operates many of South Africa’s most polluting power plants.
Moyo finds it worrying that none of these findings are new. The air pollution crisis in Africa is well documented, yet there is a lack of investment in clean energy, he said. “When people have data, they have a voice to demand change,” he said. “We need proper environmental monitoring to hold our governments and polluters accountable and help people live healthier and longer lives.”
