South African researchers tackle the global problem of poor air quality

Pale-grey smokestacks hover over the red roofs of towns across the so-called “dirty triangle” in South Africa’s industrial heartland of Gauteng province. Residents can practically taste the toxic air. But until recently, they didn’t know exactly what they were breathing.

Now they do, thanks to a low-cost air-monitoring system powered by artificial intelligence (AI) being deployed across Gauteng by researchers at the South African Consortium of Air Quality Monitoring based at South Africa’s Wits University in Johannesburg. “We are basically bringing in environmental justice,” said Lotta Mayonga, the AI and environmental studies lead for the project, known as AI_r. “We can empower the most vulnerable with information so that they can understand what is it that they breathe and what is it that is making them sick.”

The data — showing levels of particulate matter, nitrogen dioxide, sulfur dioxide and carbon monoxide — is available in real time to the public online. Mayonga said that it is also providing key information to the South African government as it works to manage the environmental impacts of the country’s industry. 

“The South African government takes very seriously air-quality monitoring,” said Bruce Mellado, leader of the AI_r project team. “They’ve deployed very expensive systems. But there's [only] so much you can do with expensive systems. You cannot deploy them every kilometre along the roads. If you really want to understand what the real picture is on the ground where the hotspots are located, you need to monitor in a very granular and dense way.”

That’s what makes the hardware component of the AI_r system a breakthrough: locally manufactured at roughly USD 100 (CAD135), it reduces production costs by a factor of 2.5. Five hundred of the monitors are going up across Gauteng. Nothing is wasted — the low-cost hardware works with existing data collection to feed into the AI_r system in real time. Using machine learning, it tracks and predicts where and when toxic levels will rise in a given community. 

All that data is published on a public dashboard, giving families, school boards and public health officials a powerful tool to address day-to-day dangers and providing researchers with critical information that can address a broad range of public health challenges in the future.

Poor air quality affects everyone, but it’s especially harmful to children, older adults and people with health conditions. The World Health Organization estimates that air pollution causes around 7 million premature deaths annually — more than the combined toll of HIV, malaria and tuberculosis in Africa. That’s why it’s important to track air pollution and take steps to reduce it — these actions help protect public health.

Not that the public didn’t have their reservations. In a country infamous for public surveillance during the apartheid era, getting people on board with a project involving monitoring and AI required some reassuring.

“People find it hard to trust anything that has to do with AI or with technology,” explained Mpho Mathebula at the Department of Psychology at Wits University. Her role on the AI_r team is community engagement. Her job is to help translate the technicalities of the system into information that people can understand, and public departments like health and education can use. “We explained to the community what the sensors are doing: they are measuring the air quality. They are not replacing anyone's work, and they are not surveilling anyone.” 

She said that once people understand the intent of the project, they get on board. 

Another team member, public health expert Mary Kawonga, offered an example of what informed citizens can do, from when they were piloting the project in and around Johannesburg in 2022. “Local communities have been struggling for years about the quality of air in the environment. They've been lobbying government to do something about it for a while, but they didn't really have the evidence. By making that data available online...they now have the evidence that they can use for their advocacy.

South Africa is working on pollution control, a challenge in a fossil fuel-driven country. Real change in the actual air quality will take years, but at least now millions more South Africans have the information they need to protect their own health. 

“It's as simple as wearing a mask,” said Mellado. “We're not talking about shutting down the economy. However, we can predict when those spikes in poor air quality will occur.”

IDRC supports the AI component of the AI_r system. Mellado and his team collaborated with partners in Switzerland to design the low-cost hardware. The AI_r system has had a lot of support in South Africa, from policymakers, the media and local businesses. In fact, a newspaper article led to support from the private sector; a partnership with Evotel, a national fibre network operator, that has helped expand the reach of sensors. 

“We deploy fiber in a lot of communities all over South African townships through a brand called NineNine. And what we see in these communities also is very poor air quality,” said Albert Oosthuysen, Evotel’s CEO. “That’s why we reached out to Bruce [Mellado] when we saw the article and offered our network.”

“It takes many different perspectives to solve a problem. It doesn't just take the government. It doesn't just take the private sector. In my view, it doesn't really matter what your background is. If you see a problem and you resonate with it, I think you should be helping,” Oosthuysen added.

Mellado said that collaboration is extremely important, particularly when it comes to AI solutions: “Scientific collaboration, scientific cooperation, exchange of ideas and exchange of knowledge is really the core of progress. We have not only been able to get in touch with scientists of the Global North, but also been able to create networks within the Global South. And that's extremely important because, suppose we develop a solution that is cost effective and can be deployed in South Africa, other countries can also take it. There might also be a technology developed in Ethiopia or Ghana that can be useful for South Africans.”

“And then, what can Canada and other countries learn from this work?,” Mellado added.

For Mayonga though, it comes right back to something more fundamental. The right to clean air is enshrined in South Africa’s constitution: “Air quality is a right, not a privilege. And everybody needs to breathe clean air.”

The AI_r project is part of the Artificial Intelligence for Development program, a partnership between IDRC and the United Kingdom’s Foreign, Commonwealth and Development Office. It is part of the work concentrating on AI for global health, housed at York University in Canada.