On a Saturday morning in Lagos, several volunteers in white “Run Lagos” t-shirts gathered for an air pollution awareness walk. They split into small groups and filed through the narrow streets, placards in hand. One read, “Air Is Free But Polluted Air Leads To Health And Climate Change Expenses.”

The walk coordinators carried portable air quality sensors, logging particulate matter (PM)2.5 (fine particles) and PM10 (coarse particles), nitrogen dioxide (NO2), humidity and temperature readings in real time. 

By the time the walk ended, the sensors had recorded a PM2.5 reading of 14 µg/m³ – a moderate morning by Lagos standards, where readings typically average between 30 to 50 μg/m³ (over 35.5μg/m³ is considered unhealthy while a reading of 12 and under is considered good).

This walk is part of a wider air quality monitoring effort in Lagos led by UrbanBetter, one of the implementing partners of the World Athletics’ Running for Clean Air initiative, which leverages city marathons and existing running communities to collect air pollution data in urban areas. Lagos is the second city to host the project after Warsaw, Poland.

Last week, the athletics governing body announced the second phase of the initiative. In partnership with the Clean Air Fund, the program is expanding its monitoring network to cover upcoming athletics events in Botswana, Thailand, and Spain.

“’Running for Clean Air’ phase two marks a defining moment: for the first time, a major sports federation is systematically monitoring air quality across multiple continents and competition types,” says World Athletics President Sebastian Coe.

Mapping the marathon route

In 2025, during the first phase in Lagos, sensors were deployed along the route of the annual Lagos City marathon.  

“The data we gathered was not surprising to us,” says Waziri Abubakar, UrbanBetter Hub Liaison Officer.

The heatmap of the PM10 levels on the route of the 2025 Lagos City Marathon shows the highest concentration on the Lagos Mainland (upper region), while Lagos Island (lowest region) showed better air quality because it is within a restricted residential area.

The readings showed consistently elevated pollution at major intersections and across the Lagos Mainland, where activities like fish smoking and poor waste management drive localised spikes. 

The levels of the greenhouse gas, NO2, followed a similar pattern to PM10, with the highest readings in the upper region. However, readings were also high towards the end of the race. NO2 is a traffic-related air pollutant associated with cardiovascular and respiratory mortality following short-term exposure.

UrbanBetter now integrates these findings into the state’s regulatory framework by sharing data with the Lagos State Environmental Protection Agency (LASEPA), the state’s primary environmental regulator.

“A primary outcome of this data was the decision to reroute the 2026 marathon to Lagos Island to leverage its superior air quality,” says Abubakar. 

While the air quality data supported this shift, the race organisers’ official statement omitted environmental factors, instead framing the change as an evolution and a commitment to their values of “excellence, safety, and world-class delivery.”

Following the end of the first phase, World Athletics gifted the air-monitoring device to LASEPA, with the agency committing to using the data for policy decisions. According to Abubakar, the agency is also looking at setting up low-emission zones in Lagos, with the data helping determine where those zones would be located.

Three monitors for 20 million people

Sub-Saharan Africa averages one ground-level air quality monitor per 16 million people. Lagos now has three reference-grade monitors and several low-cost sensors for its 20 million residents. 

“What was missing and is still missing is that for a population of over 20 million, that is not enough,” says Abubakar.  

One of the three reference monitors in Lagos is a United States Embassy station with an uncertain future amid shifting American environmental policies.

Air pollution continues to be a leading risk factor for early death, surpassed only by high blood pressure, and 90% of the burden falls on low- and middle-income countries, according to the State of Global Air 2025 report.

The report attributes around 200,000 deaths in Nigeria to air pollution annually, making it the country’s third leading risk factor for premature death.

Grassroots data, government-sized gaps

In the absence of government monitoring, low-cost sensors have become an important source of data in resource-constrained places like Nigeria. 

The 2023 IQAir World Air Quality Report found that more than half of the world’s air quality data came from grassroots community efforts.

The second phase of the World Athletics’ Running for Clean Air initiative will kick off at the World Athletics Relays in Gaborone, Botswana, a country whose primary air quality legislation dates back to 1971. 

The WHO’s Health and Environment Scorecard gives Botswana a policy score of 24 out of 100, reflecting weak adoption and implementation of national plans to address environmental health threats. 

“The data we generate across Gaborone, Bangkok and Valencia will be transformative for World Athletics, for our member federations, and for the broader sports community,” says Dr Stéphane Bermon, Director of the Health and Science Department at World Athletics.

The closest precedent to the sport’s body approach is India’s System of Air Quality Forecasting and Research (SAFAR). It was built for the 2010 Delhi Commonwealth Games and now a permanent national forecasting network covering five Indian cities. But SAFAR was designed from the start as a government project with sustained public funding.

When the runners go home

Lagos State has expanded its sensor network roughly fivefold between 2024 and 2025 to 114 units, with a target of 200 sensors by late 2026. But that growth has been driven in part by foreign donations and partnerships.

The fiscal picture remains unclear as its air quality commitments are buried within a broad environmental budget with no public breakdown. 

While the overall state budget grew by 32% in 2026, the specific allocation for the environment sector decreased by nearly 18% compared to 2025, falling to 235.96 billion Naira (roughly $174 million).

The initiative has shown it can collect data in places that lack it. What is yet to be seen is if this data creates a lasting system or remains a snapshot from race day.

“It would require political will and sensitisation of key stakeholders on how air quality affects the health of people living in their cities to get the buy-in of the government and citizens,” says Abubakar.

Image Credits: UrbanBetter, Wold Athletics, World Athletics, Ekuma Barnabas.