The WHO estimates that a million children die every year in developing countries from acute respiratory infections. A major cause of these infections is air pollution from the wood, animal dung, and other biofuels that are burnt everyday in their own homes.
The toll from this “indoor” air pollution is heaviest on poor families in South Asia and Africa. This has prompted the World Bank to include reduction of indoor air pollution as a critical element of its environment strategy.
However, little has been known about either the actual air quality in poor households or its impact on health. This lack of information—largely due to the cost of monitoring indoor air and conducting medical tests—has slowed the design of strategic solutions.
A recent World Bank research effort in Bangladesh finds that young children and poorly-educated women in poor households face pollution exposures that are about 1.6 times higher than those for their counterparts in higher-income households.
The Bangladesh research work, led by Susmita Dasgupta and David Wheeler, attempts to reduce the knowledge gap about indoor air pollution using the latest air monitoring technology, national household survey data, and a set of controlled experiments.
Poor households in Bangladesh, as in other parts of Asia, Latin America, and Sub-Saharan Africa, depend heavily on biomass fuels for cooking because they can’t afford or can’t procure cleaner fuel like cooking gas and kerosene.
Biomass fuels are considered “dirty” because they pollute the environment heavily and lodge tiny particles in people’s lungs that cannot be expelled by natural clearance mechanisms like coughing.
“When people are unable to switch to clean fuels, we suggest simple changes in the way they ventilate their homes and configure their living spaces,” said Susmita Dasgupta, Lead Environmental Economist at the World Bank. “Although these solutions may not be ideal, they go a long way in producing relatively safe breathing conditions.”
Dasgupta and team found that indoor air quality varied widely based not only the fuel used, but also on where the food was cooked, the building materials used in the home, ventilation practices, and even the changing seasons. In seasons during which there is a lot of dust outdoors, for instance, it might be safer to cook indoors.
“Just leaving a door open after cooking can help reduce health hazards,” said David Wheeler, Senior Fellow, Center for Global Development. “But the best thing to do is to move burning biomass away from houses.”
Research also shows that for children in a typical household, pollution exposure can be halved by doing two simple things: increasing their outdoor time from three to five or six hours per day, and concentrating outdoor time during peak cooking periods.
The study concludes that a national “clean household” promotion program, combined with effective public education on the associated health benefits, could reduce Indoor Air Pollution exposure to much safer levels for many poor families in Bangladesh.