This is the second in a three-part series exploring the setbacks of transitioning from wood to LPG  in the town of Mbalmayo.

In many African homes, the kitchen is the heart of the family. It’s where traditions are shared and passed down from one generation to the next. But behind the warmth of cooking fires  lurks an invisible killer: household air pollution. In the six households we observed, women cooking over open fires or charcoal inhale far more air pollutants than those who use LPG.

To better understand the extent of this thread, I spoke with Dr. Christopher Sola Olopade, a pulmonologist and professor of medicine at the University of Chicago. Originally from Nigeria, Dr. Olopade is a pioneer in research on household air pollution in Africa. He has spent his career studying how cooking smoke impacts women’s and children’s health,particularly respiratory illnesses.

His work has earned him numerous accolades, including the Humanitarian Award from the American College of Chest Physicians in 2010.

“There is enough out there to show that exposure to the combustion of biomass is one of the major contributors to the adverse effects of household air pollution, that kill around 3 million people every year, preventable deaths, mostly women, because most of the time they are responsible for the cooking for their family, and young children who stay with their mother,” he says.

More than 20 years ago in Nigeria, he led a study involving 59 women who cooked with biomass. The goal was to measure concentrations of two deadly, invisible enemies : carbon monoxide (CO) and fine particulate matter (PM2.5), inside their homes. These pollutants are especially dangerous because they’re invisible. PM2.5 particles are so small that they bypass the body’s natural defenses and lodge deep into the lungs. The finest particles can even cross into the bloodstream, potentially affecting all of the body’s organs. Carbon monoxide is odourless and impairs the ability of the blood to deliver oxygen to the brain and other organs, and at high levels causes fatal poisoning.

The results were alarming:

“Within just one hour, we recorded up to 5000 µg/m³ of PM2.5 and 200 ppm of carbon monoxide.”

These levels are well beyond the safe thresholds. For context, the World Health Organization (WHO) recommends a daily average limit of 5 µg/m³ for PM2.5 and 4 ppm for carbon monoxide.

“It’s the incomplete combustion of unclean fuels :  biomass, sawdust, charcoal, cow dung ; that causes air pollution,” he explains. “This releases fine particles, carbon monoxide, polycyclic aromatic hydrocarbons, and heavy metals. These pollutants bypass the respiratory system’s defenses and go straight into the lungs.”

Despite never smoking a single cigarette, over 30% of the women in his study already showed signs of chronic respiratory illness. Dr. Olopade is clear: “ To put it into perspective, such exposure is equivalent to smoking three to four packs of cigarettes a day. The effects on lung function are profound.”

Regular exposure to this type of pollution can cause or worsen a range of conditions: asthma, chronic obstructive pulmonary disease (COPD), cardiovascular disease, stroke, lung cancer, respiratory infections, and even premature death. Exposure during pregnancy is particularly harmful, as pollutants can cross the placental barrier, affecting the unborn child by reducing birth weight, impairing lung growth, and increasing the risk of developmental delays and preterm birth. Long-term exposure can also affect cognitive development. For Dr. Sola, the connection between cooking fuels and health cannot be ignored. He stresses that household air pollution is a deadly, urgent issue to be tackle because “nobody should die cooking for their family.”

This warning from Nigeria echoes the story that Mama Verra in Mbalmayo shared with me during her interview. She recalls:

“My husband’s classmate lost his wife and two kids because of charcoal. They cooked indoors and fell asleep without putting the fire out. That was two years ago, in Bamenda.”  Since then, she refuses to cook with charcoal inside the house. She moved her kitchen outdoors — a life-saving decision.

According to the Global State of Air 2019, air pollution was responsible for over 693,000 deaths in sub-Saharan Africa, accounting for 30% of the global burden linked to household air pollution. A staggering number. But what statistics don’t reveal is the slow, silent erosion of millions of shortened lives

The Air Quality Life Index from the University of Chicago estimates that living in a polluted environment can reduce life expectancy by 2.7 years. An invisible yet very real theft—one that spares no one, least of all the most vulnerable.

Air pollution kills quietly. In 2019, it claimed  3.2 million lives worldwide, more than the number of COVID-19 deaths recorded in 2020. It also causes more harm than HIV, malaria, or tuberculosis, those other global scourges that receive far more media attention.

A global challenge, A health emergency

Faced with this health threat, the World Health Organization (WHO) has made the fight against air pollution a key part of the Sustainable Development Goals (SDGs). In particular, SDG 7 calls on countries to ensure universal access to modern, sustainable, and affordable energy.

Beyond respiratory diseases, air pollution is a major risk factor for non-communicable diseases: strokes, heart attacks, cancer, and chronic illnesses. The threat is widespread, insidious, and ever-present.

WHO urges governments to produce reliable data on household energy use and its health impacts essential to guide public policy and accelerate energy transitions.

Cameroon joins the regional Momentum

Cameroon is not standing idle. Several research initiatives are underway to tackle household air pollution. Among them is the NIHR CLEAN-Air(Africa) Global Health Research Group, based at the Douala General Hospital, in partnership with the University of Liverpool. The project, titled NIHR Global Health Research Unit on Clean Energy Access for the Prevention of Non-communicable Diseases through Clean Air in Africa by 2030, has become, since 2022, a large-scale global health research unit operating in Kenya, Cameroon, Rwanda, Tanzania, and Uganda. It brings together international public health researchers and clinical experts from both the UK and sub-Saharan Africa.

In Cameroon, the project has been active for several years in Mbalmayo. In Douala, I met Professor Bertrand Hugo Mbatchou, a pulmonologist and the project’s national coordinator, who speaks about it with passion:

“In Mbalmayo, we conduct research to assess households’ dependence on both clean and polluting fuels. We work with a large population to better understand the impact of household air pollution on their respiratory health. The link between fuel used and respiratory health is direct, measurable, and undeniable.”

Data that makes you cough

A former study done between 2019- 2020 on 84 households ( 43 cooking with LPG and 41 with wood) in Mbalmayo were equipped with sensors to monitor indoor air pollution. Professor Mbatchou notes:

“Our results revealed very high levels of fine particulate matter (PM2.5), especially in households using solid fuels. In some cases, PM2.5 concentrations exceeded far beyond the WHO recommended limit for daily exposure to PM2.5.”

The results of the daily  concentrations of speak volumes :

• 44 µg/m³ of PM2.5
• 287 µg/m³

These findings were not only published in the prestigious journal The Lancet Planetary Health (source), but were also presented during workshops with the Ministry of Health to inform and engage national decision-makers.

Other ongoing research components of the CLEAN-Air(Africa) project include studies on domestic burns, lung function tests (called spirometry) among women, and efforts to map out all health risks linked to indoor pollution. Spirometry is a simple test that measures how well a person can breathe. It helps detect lung problems early, such as those caused by exposure to smoke from cooking with polluting fuels.

LPG for All? A long Way to go

But measuring is only the beginning, action is what truly matters. And this is where the challenge becomes political.

During my investigation, I visited the Gas Sub-Directorate at the Ministry of Water and Energy in Mvog-Ada, in Yaoundé. There, I learned that in 2016, the Cameroonian government launched an ambitious Master Plan for Butane Gas Development. The goal? To increase domestic LPG use from 12% to 58% of households by 2035 , a giant leap aligned with Cameroon’s commitment to achieving SDG 7.

This Master Plan sets out to:

• Reach 383,000 tons of national LPG consumption;
• Put 6.8 million additional LPG cylinders in circulation;
• Open 6,600 new distribution points, especially in rural areas;
• Drastically reduce pressure on forests, 4 million tons of firewood saved per year, or 15 million trees spared;
• Cut 3.4 million tons of CO₂ emissions annually.

The effort is cross-sectoral, involving several key ministries: the Ministry of Public Health (MINSANTE), which handles health-related issues; the Ministry of Environment, Nature Protection, and Sustainable Development (MINEPDED), responsible for managing environmental and natural resource issues; and the Ministry of Commerce (MINCOMMERCE), which regulates commercial activities. Key public institutions, such as the Hydrocarbon Price Stabilization Fund (CSPH), the National Oil Company of Cameroon (SNH), and the National Refining Company (SONARA), also play vital roles in the implementation of these initiatives. International partners like the United Nations Development Programme (UNDP) and the Sustainable Energy for All initiative (SEforALL) are also engaged in supporting these efforts at a global scale.

A key player in this transition is the Global LPG Partnership (GLPGP), an international not-for-profit organization supporting energy policies in low- and middle-income countries. In Cameroon, GLPGP works to expand the LPG market, facilitate distribution, and strengthen storage and filling infrastructure.

Between Ambition and Reality

Yet nine years after the plan’s launch, reality still resists change.

In towns like Mbalmayo, LPG equipment remains expensive, access is limited, and traditional habits persist. Firewood still reigns, sometimes by choice, more often out of necessity.

Changing policy is one thing. Changing mindsets is another.

What is Next?

In the last article of this series, we will take a critical look at the Master Plan: what results have been achieved a decade later? What are the main obstacles? What solutions are being proposed? And how can we convince households that clean cooking is a right, not a luxury? Because if breathing kills, breathing better can save lives.