Approximately 2.3 billion people cook using open fires or inefficient stoves fueled by kerosene, wood and coal. This exposes them to harmful air pollution that the World Health Organization (WHO) says is responsible for an estimated 3.2 million deaths per year, including 237,000 deaths of children under the age of 5 in 2020.
Exposure to household air pollutants also leads to noncommunicable diseases including stroke, heart disease, chronic obstructive pulmonary disease (COPD) and lung cancer, with women and children typically being at the greatest risk, WHO states.
A team of Emory University researchers — led by Thomas F. Clasen, PhD, professor in the Gangarosa Department of Environmental Health at the Rollins School of Public Health, and in partnership with international collaborators — conducted a multi-country study to assess the health effects of cooking effects of cooking with liquefied petroleum gas (LPG) instead of harmful traditional biomass fuels such as wood, charcoal and dung.
The study, called the Household Air Pollution Intervention Network (HAPIN) Trial, established centers in India, Guatemala, Peru and Rwanda. Each center recruited 800 pregnant women and provided their households with an LPG cookstove and free fuel through the first year of their infant’s life. The trial monitored exposure to household air pollution and measured health outcomes in the women, their infants and older adult women in the same household.
Two findings published this month in The New England Journal of Medicine analyzed the effects of cooking with LPG on the instances of severe infant pneumonia and stunting in infants compared to cooking with biomass fuels such as wood, charcoal and dung. Pneumonia is a major killer of young children in low-income countries, and stunting (or reaching a low height for age) is an indicator of some of the most serious adverse health effects longer term.
Researchers found no evidence that the intervention was effective in preventing pneumonia or stunting.
“These results were surprising given prior research that links household air pollution and adverse health effects,” Clasen says. “While the LPG stoves and fuel intervention was effective in substantially reducing exposure to air pollution and the burden of collecting and cooking on biomass, it did not reduce the risk of these important health outcomes.”
The HAPIN study is continuing to follow children born into the trial to assess longer term health endpoints, including neurocognitive development and lung function. The results on pneumonia and stunting, however, may be a disappointment to those seeking affordable, scalable solutions to address the adverse health effects of air pollution in low-resource settings.
“Cleaner cooking fuels may be part of the answer, but more comprehensive strategies may be necessary to achieve genuine health gains,” Clasen says.