Study: Solid fuels exposing families to toxic pollutants

A section of Kibera slums. Charcoal, firewood and plastic burnt in cramped, unventilated spaces pose health risks. [Jonah Onyango, Standard]

Residents of informal settlements are exposed to worrying levels of air pollution, new scientific research shows.

A two-year study in Mukuru, Kenya, and Ndirande, Malawi, found that charcoal and firewood for cooking emit toxic pollutants that pose severe health risks.

In addition, most families cook in cramped, unventilated spaces, exposing them to large volumes of harmful pollution every day. This is done by using plastic bottles, maize stalks and homemade charcoal briquettes.

According to findings these pollutants are linked to respiratory illnesses, such as asthma, and can lead to increased mortality rates.

In two slums, a team led by Dr Isabelle Uny from the University of Stirling's Institute for Social Marketing and Health evaluated household air pollution (HAP). As part of a study examining the practices, habits, and lived experiences of people who use solid fuels for cooking. This includes wood, biomass waste, charcoal, and animal dung.

Dr Uny said: “These informal settlements or slums have little infrastructure, and people affected by poverty use whatever fuels they can afford to cook. Solid fuels cause the most damage to health. It's women – who are often the main cooks – and children who are disproportionately exposed to household air pollution."

The researchers measured PM2.5, which is a tiny particle – if you think of the size of a strand of hair, PM2.5 would be much, much smaller.

The recommended World Health Organisation guidelines state that a person should not be exposed to more than 12.5 micrograms per cubic metre in a 24-hour period.

Data show high levels of pollution daily, 600 μg/m3 in Kenya and about 2000 μg/m3 in Malawi.

"We’re talking about really, really high levels of exposure to tiny, tiny particles in the air of soot that people are inhaling every day, causing significant harm to their health,” Uny said.

More than 2 billion people worldwide use solid fuel for their cooking and heating needs and (HAP) can be linked to approximately 3.2 million deaths a year - 700,000 of which are in sub-Saharan Africa, with HAP linked to diseases including stroke, heart disease, and lung cancer.

The research was funded by the UK Research and Innovation Arts and Humanities Research Council and carried out in partnership with experts from the Kenya Medical Research Institute (KEMRI) and Malawi University of Business and Applied Sciences (MUBAS).

Fred Orina, of KEMRI, said: “This was a unique study in that we worked at a grassroots level with communities in order to find out from their perspective what the most pressing issues around using charcoal, wood and other solid fuels for cooking were and the type of solutions they think are the most sustainable, affordable and most feasible to improve air quality and health.”

As part of the research, the academics embedded themselves in the two informal settlements, conducting walking interviews – where the interviewer walks with and films the participant’s journey from sourcing, buying or collecting fuel to preparing the fire or stove and cooking.

The team also used a novel research method – 'Photovoice’, where 20 participants were given camera phones to document their own experiences of fuel gathering, food preparation, cooking and household air pollution over a two-week period.

During the study, one participant told researchers: “You will hear the children complaining about 'smoke, smoke’. It overwhelms me and I even have difficulty breathing when lighting the stove. I get headaches,”

Limbani Kalumbi, of Malawi University of Business and Applied Sciences (MUBAS) said: “People are driven to use these fuel sources, not because they want to, but due to issues around household income, access to certain fuels and the availability – or lack of availability – of cleaner sources of fuel.

“We discussed potential solutions with community members and they are interested in better access to cleaner fuels. This includes LPG gas and in the longer term a good, affordable supply of electricity.”

Dr Uny added: “The need is great. Previous interventions have seen sub-Saharan communities provided with more fuel-efficient stoves, which provide environmental benefits but don't improve health implications.

“We shared our findings through a poster exhibition in Kenya and Malawi and discussed solutions with local people as well as with policymakers and other decision-makers, to highlight the issues further and discuss possible ways in which the impact on health of solid fuel use could be improved in line with the aspirations of the Kenyan and Malawian governments.”