Letter from the Director

John R. Balmes

Exposure to smoke from combustion of solid fuels such as wood, dung, crop waste and coal leads to low birth weight and pneumonia in infants and cataracts, chronic obstructive lung disease, cardiovascular disease and lung cancer in adults – mainly women who cook using open fires.  With approximately half of the world’s population, primarily in developing countries, exposed to smoke from solid fuel combustion, household air pollution from this source is a major contributor to the global burden of disease.  Despite the large impact of household air pollution on health, relatively little attention has been paid to the problem.

COEH member Kirk Smith has strived for over three decades to increase the awareness of household air pollution as a critical driver of ill health.  He was the first to measure levels of exposure to various components of smoke using personal monitoring of a woman cooking with biomass fuel, including particulate matter and carbon monoxide. Along with demonstrating that high levels of exposure to smoke occur around the world from cooking with biomass fuel, Dr. Smith sought to establish that improved cook stoves were an intervention that would reduce ill health due to biomass smoke emissions.  Though it took many years before he could find the appropriate site and obtain the funding to conduct such an intervention study, I am happy to report the paper describing the results of the world’s first randomized controlled trial of a chimney stove in rural Guatemala is in press at the Lancet.

Why is this randomized controlled trial so important?  One reason for the relative inattention to household air pollution has been the lack of data documenting the effectiveness of interventions to reduce exposure for the prevention of health outcomes.  A health ministry in a developing country with limited resources is more likely to employ a pneumococcal vaccination program to prevent pneumonia in young children rather than mass distribute cleaner cook stoves.  Quantitative evidence proving efficacy is needed to support expending limited resources on stoves.  Dr. Smith has been for years encouraging policy makers in developing countries and funders in developed countries to take concrete actions to ameliorate the problem of household air pollution.  While he has received numerous awards for his pioneering work, his efforts to stimulate government actions were of mixed success until recently. 

Over the last two years, however, there has been a remarkable sea change in attitudes about this problem.  As many of you may know, Hilary Clinton has long been interested in the health of women and children.  After being named U.S. Secretary of State, she became aware of the huge public health impacts of household air pollution in developing countries and demanded action.  As a result, a Global Alliance for Clean Cookstoves (GACC) was established that includes the governments of 16 countries, companies and nongovernmental organizations.  The goal of the GACC is to distribute 100 million clean stoves to households in need around the world by 2020.  Multiple U.S. governmental agencies have been mobilized to work on this ambitious goal, including USAID, CDC, NIH, and EPA.

As recently as two years ago, a review of a grant application to NIH Dr. Smith and I submitted indicated that since biomass smoke exposure was not a problem in the United States, our proposed research project was not of interest.  But in May of this year, the NIH hosted an international conference to highlight knowledge gaps regarding health effects of household air pollution and methods to reduce exposures.  As the feature article in this issue reports, Dr. Smith will be conducting a pilot study in India that is planned to lead into the launching of a major clean stove intervention study in that country.

As I’ve noted, the effects of exposure to harmful cooking smoke have historically received limited funding and research attention in comparison to other risk factors (e.g., lack of clean water, sanitation, and hygiene) or diseases (e.g., malaria) that lead to similar health outcomes.  In addition to a lack of research into the impacts of biomass smoke exposure and the potential benefits of cleaner stoves, there also has been a lack of affordable, advanced solutions that yield clear benefits and achieve user acceptance. 

Hopefully, with this latest push to distribute clean cook stoves by the GACC, appropriate research and evaluation of various stove interventions will be conducted to ensure the efforts achieve success.

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