BLACK SOOT: Why Port Harcourt’s air matters—and what can be done

BLACK SOOT
Why Port Harcourt’s air matters—and what can be done

Figure 1. Early-morning haze over Port Harcourt: the visible face of a complex air-pollution problem. Source: Eniola Ore (2022), ArcGIS StoryMap. Original image credit is not specified in the StoryMap.

THE BIG IDEA  Soot is more than dirt on a surface. Fine combustion particles can enter deep into the lungs. The pollution has several possible sources, so lasting solutions require measurement, enforcement, cleaner energy, safer livelihoods, and public accountability.

 

StoryMap author: Eniola Ore  •  December 4, 2022

Academic supervision: Prof. Gervais Wafo Tabopda, Georgia Institute of Technology

Citizen-paper adaptation: August 2026

 

A city waking up under black dust

Since late 2016, residents of Port Harcourt and nearby communities have reported black particles settling on floors, windows, cars, plants, bed linen—and sometimes on children’s hands and feet. The deposits are especially noticeable in the morning. What looks like ordinary dust may contain particles produced by incomplete combustion of petroleum and other fuels.

Figure 2. Soot deposition on a resident’s hand makes the exposure visible, but what cannot be seen may be even more important. Source: Eniola Ore (2022), ArcGIS StoryMap. Original image credit is not specified in the StoryMap.

What does “soot” mean?

Three terms are often mixed together. They are related, but they are not identical:

Term	Plain-language meaning
PM₂.₅	Particles no wider than 2.5 micrometres. They can travel deep into the lungs and are the main health indicator used in many air-quality studies.
Soot	A dark mixture formed by incomplete burning. Its composition changes with the fuel and combustion conditions.
Black carbon	A light-absorbing carbon component of soot. It affects health and also warms the climate.
WHY PRECISION MATTERS  A map of PM₂.₅ is not automatically a map of black carbon. Scientists need to identify exactly what was measured, how it was measured, and over what period.

 

Where is the problem?

Port Harcourt sits in the oil-producing Niger Delta. The city is linked to creeks, pipelines, industrial areas, roads, settlements, and flare sites. Wind and the height of the atmospheric mixing layer determine where pollutants travel and where they accumulate. Calm, stable early-morning air can keep pollution closer to the ground.

Figure 3. Gas flares and footprint locations in the Niger Delta. The pattern is useful for identifying possible source areas, but proximity alone does not prove causation. Source: Eniola Ore (2022), ArcGIS StoryMap. Original image credit is not specified in the StoryMap.

Figure 4. A closer view of flare locations and footprints near Port Harcourt. Wind direction, flare performance, and other emission sources must be considered when interpreting the map. Source: Eniola Ore (2022), ArcGIS StoryMap. Original image credit is not specified in the StoryMap.

READING A MAP CAREFULLY  Maps reveal patterns and help ask better questions. To prove which source caused pollution at a neighborhood, scientists also need ground monitors, chemical fingerprints, weather data, and atmospheric models.

 

 

Where can the soot come from?

Figure 5. An artisanal or illegal crude-oil refining operation. Incomplete combustion can release thick smoke and fine particles. Source: Eniola Ore (2022), ArcGIS StoryMap. Original image credit is not specified in the StoryMap.

The StoryMap points to artisanal refining and activity near waterways. Scientific studies agree that petroleum combustion is an important concern, but Port Harcourt’s air is affected by several overlapping sources:

·   artisanal refining and open burning of petroleum products;

·   gas flaring, refineries, petrochemical plants, asphalt works, and other industry;

·   diesel and petrol generators used during unreliable electricity supply;

·   cars, minibuses, trucks, and poorly maintained engines;

·   burning of tyres, waste, biomass, and materials used in some abattoirs; and

·   open destruction of seized crude oil, tankers, or makeshift refining equipment.

What research tells us

A 2017 atmospheric study modeled pollution moving from areas south and southwest of Port Harcourt and found episode concentrations reaching 180 µg/m³ under selected conditions. A 2019 study of gas flaring showed that flare size, combustion efficiency, wind, and atmospheric stability strongly influence ground-level black carbon. These studies support action—but they also show why no single map can explain every pollution episode.

 

What can soot do to health?

Figure 6. A public-awareness collage used in the StoryMap to communicate possible health effects. Source: Eniola Ore (2022), ArcGIS StoryMap. Original image credit is not specified in the StoryMap.

Fine particles can irritate the airways and worsen asthma. Long-term exposure to PM₂.₅ is linked internationally with heart and lung disease, stroke, lung cancer, adverse pregnancy outcomes, and premature death. People with asthma, heart disease, or chronic lung disease are more vulnerable. Children, older adults, pregnant people, outdoor workers, and people without access to filtration may face greater risk.

HEALTH BENCHMARK  The World Health Organization’s 2021 guideline for PM₂.₅ is 5 µg/m³ as an annual average and 15 µg/m³ as a 24-hour average. These are health-protection goals, not a dividing line between “safe” and “dangerous.” Comparisons must use the same averaging period.

 

What is known locally?

Port Harcourt studies have reported high particulate levels, morning peaks, and metals—including nickel, chromium, cadmium, and lead—in collected soot. A 2026 systematic review of 21 Niger Delta observational studies found possible links between oil- and gas-related pollution and respiratory symptoms, asthma, reduced lung function, chronic obstructive pulmonary disease, and hypertension. The authors judged the certainty as low to moderate because studies measured exposure and health outcomes in different ways.

What this means for citizens

The health concern is credible and prevention is justified. At the same time, scientists should avoid claiming that a particular illness was caused by a particular soot source without appropriate exposure and medical evidence.

The environment also carries the burden

Figure 7. Soot deposited on vegetation. Surface deposition is visible evidence that pollutants move from air to land and water. Source: Eniola Ore (2022), ArcGIS StoryMap. Original image credit is not specified in the StoryMap.

Particles can settle on leaves, roofs, soils, creeks, rainwater collection systems, and household surfaces. Soot can reduce visibility and block some sunlight from reaching leaves. Chemical components may enter soil, sediment, and water. The StoryMap also reports “black rain,” crop damage, and declines in fish and crabs.

A SCIENTIFIC CAUTION  Those ecological observations deserve investigation, but soot is not the only pressure on the Niger Delta. Oil spills, wastewater, habitat loss, dredging, salinity changes, and other contamination can also affect fish, crops, and waterways. Good studies compare polluted and reference sites over time.

 

Figure 8. Images of smoke, haze, and black rain illustrate how the pollution is experienced in everyday life. Source: Eniola Ore (2022), ArcGIS StoryMap. Original image credit is not specified in the StoryMap.

 

What government and industry should do

1. Measure and publish

·   Operate a quality-assured network with at least one reference-grade monitor and well-calibrated lower-cost sensors.

·   Publish validated hourly readings, health advisories, missing-data flags, methods, and annual trends.

·   Sample PM₂.₅ filters for black carbon, metals, ions, and petroleum-related organic compounds to identify sources.

2. Stop pollution at the source

·   End open burning of seized crude oil and equipment; use secure recovery and controlled treatment.

·   Meter gas flaring, verify flare efficiency, enforce deadlines, detect leaks, and capture or use associated gas.

·   Control industrial stacks, tyre and waste burning, smoky vehicles, and high-emitting generators.

·   Improve reliable electricity and clean transport so families and businesses do not depend on dirty combustion.

3. Protect health now

·   Issue clear alerts for high-pollution days and prepare clinics, schools, and workplaces.

·   Create clean-air rooms using correctly sized HEPA filtration and prioritize vulnerable households and institutions.

·   Provide well-fitting N95/FFP2 masks during severe episodes; ordinary cloth masks do not reliably filter fine particles.

·   Track asthma attacks, respiratory visits, cardiovascular events, pregnancy outcomes, and school absences while protecting privacy.

4. Make enforcement fair and durable

·   Target organizers, financing, stolen-oil supply chains, and dangerous facilities—not only low-income workers.

·   Pair enforcement with safe livelihoods, remediation jobs, skills training, and reliable legal energy supplies.

·   Include waterfront communities in sensor placement, reporting, enforcement priorities, and evaluation.

 

What residents can do

FIRST PRIORITY  Reduce exposure when pollution is visibly severe or official readings are high. Personal action cannot replace government and industrial responsibility, but it can lower short-term risk.

 

Helpful actions

Actions to avoid

·   Follow trusted air-quality alerts. ·   Keep windows closed during intense smoke episodes when feasible. ·   Use a HEPA air cleaner or a correctly fitted filter system; replace filters as recommended. ·   Wear a well-fitting N95/FFP2 when outdoor exposure cannot be avoided. ·   Seek medical care for severe breathlessness, chest pain, blue lips, confusion, or worsening asthma. ·   Document repeated pollution events with date, time, location, weather, and photographs.

·   Do not burn collected soot, rubbish, tyres, or petroleum waste. ·   Do not use ozone-producing air cleaners. ·   Do not assume a surgical or cloth mask provides the same protection as a respirator. ·   Do not rely on smell or visibility alone—fine particles may remain high when the air looks clearer. ·   Do not stop prescribed asthma or heart medicines without clinical advice.

Questions citizens can ask

·   Where is the nearest monitor, and when was it last calibrated?

·   Which pollutant is being reported—PM₂.₅, PM₁₀, AQI, or black carbon—and for what averaging period?

·   Which sources were tested, and what chemical or meteorological evidence supports the conclusion?

·   Are results, enforcement actions, and emission reductions publicly available?

·   Are the most exposed communities represented in decisions and receiving health protection?

 

From a powerful StoryMap to public action

Eniola Ore’s StoryMap, created under the supervision of Prof. Gervais Wafo Tabopda at the Georgia Institute of Technology, gives Port Harcourt’s soot crisis a human and geographic form. Its images show the burden residents describe; its maps help identify where investigation is needed; and its narrative connects air quality with health, ecosystems, energy, livelihoods, and governance.

The next step is to make the evidence more reproducible. Every map should state its source, date, unit, averaging period, resolution, and uncertainty. PM₂.₅, soot, black carbon, and AQI should be clearly distinguished. Live web readings should be archived with dates. Source claims should be tested with chemical analysis, wind data, and atmospheric modeling. Health and ecological claims should be linked to studies designed to test them.

BOTTOM LINE  Port Harcourt does not need to wait for perfect certainty before reducing harmful combustion. The best response combines immediate health protection with transparent monitoring, source control, cleaner energy, safe enforcement, health surveillance, livelihood transition, and community oversight.

 

A short reading list

Ede, P. N., & Edokpa, D. O. (2017). Satellite determination of particulate load over Port Harcourt during black soot incidents. Journal of Atmospheric Pollution, 5(2), 55–61. https://doi.org/10.12691/jap-5-2-3

Fawole, O. G., Cai, X., Abiye, O. E., & MacKenzie, A. R. (2019). Dispersion of gas flaring emissions in the Niger Delta. Environmental Pollution, 246, 284–293. https://doi.org/10.1016/j.envpol.2018.12.021

Kalagbor, I. A., Dibofori-Orji, A. N., & Ekpete, O. A. (2019). Exposure to heavy metals in soot samples and cancer risk assessment in Port Harcourt, Nigeria. Journal of Health & Pollution, 9(24), 191211. https://doi.org/10.5696/2156-9614-9.24.191211

Obute, O. P., et al. (2026). Cardiopulmonary health effects of oil- and gas-related environmental pollution in the Niger Delta, Nigeria: A systematic review. Air Quality, Atmosphere & Health, 19, Article 105. https://doi.org/10.1007/s11869-026-01989-4

Ore, E. (2022, December 4). Black Soot in Port Harcourt, Rivers State [ArcGIS StoryMap]. https://storymaps.arcgis.com/stories/2b196407e3124aa18f85e1fb5477c57b

World Health Organization. (2021). WHO global air quality guidelines. https://www.who.int/publications/i/item/9789240034228

Yakubu, O. H. (2018). Particle (soot) pollution in Port Harcourt Rivers State, Nigeria—Double air pollution burden? Environments, 5(1), 2. https://doi.org/10.3390/environments5010002

Image-use note. Figures reproduced from the reviewed StoryMap for scholarly criticism, public education, and discussion. The StoryMap identifies its author but does not provide original creator credits for every embedded photograph. Further republication should verify the underlying image rights and add complete creator/licence information.