Indoor Respirable Particulate Matter Concentrations from an Open

---

Environ. Sci. Technol. 2001, 35, 2650-2655

Indoor Respirable Particulate Matter Concentrations from an Open Fire, Improved Cookstove, and LPG/Open Fire Combination in a Rural Guatemalan Community RACHEL ALBALAK* Department of International Health, Rollins School of Public Health of Emory University, 1518 Clifton Road, N.E., Atlanta, Georgia 30322 NIGEL BRUCE Department of Public Health, University of Liverpool, Whelan Building, Quadrangle, Liverpool L69 3GB, U.K. JOHN P. MCCRACKEN Harvard School of Public Health, Department of Environmental Health, 665 Huntington Avenue, Boston, Massachusetts 02115 KIRK R. SMITH Environmental Health Sciences, School of Public Health, University of California, Berkeley, California 94720-7360 THELMA DE GALLARDO University of San Carlos, Guatemala City, Guatemala

Improved biomass cookstoves have the potential to reduce pollutant emissions and thereby reduce pollution exposure among populations in developing countries who cook daily with biomass fuels. However, evaluation of such interventions has been very limited. This article presents results from a study carried out in 30 households in rural Guatemala. Twenty-four hour PM3.5 concentrations were compared over 8 months for three fuel/cookstove conditions (n ) 10 households for each condition): a traditional open fire cookstove, an improved cookstove called the plancha mejorada, and a liquefied petroleum gas (LPG) stove/ open fire combination. Twenty-four hour geometric mean PM3.5 concentrations were 1560 µg/m3 (n ) 58; 95% C.I. 1310, 1850), 280 µg/m3 (n ) 59; 95% C.I. 240-320), and 850 µg/ m3 (n ) 60; 95% C.I. 680-1050) for the open fire, plancha, and LPG/open fire combination, respectively. A generalized estimating equation model showed a 45% reduction in PM3.5 concentrations for the LPG/open fire combination as compared to the open fire alone. The difference approached significance (p < 0.0737). The plancha showed an 85% reduction in PM3.5 concentrations as compared to the open fire (p < 0.0001). An analysis of the interaction of time with stove type showed that the temporal trend in pollution did not significantly differ among the three stove types. The reduced PM3.5 concentrations were maintained over time. Season did not affect pollutant concentrations. Of the two interventions, the plancha appears to offer the best prospects for achieving substantial reductions in indoor air 2650

9

ENVIRONMENTAL SCIENCE & TECHNOLOGY / VOL. 35, NO. 13, 2001

pollution levels, although issues of cost and stove maintenance remain to be addressed.

Introduction More than 40% of the world’s population relies on unprocessed solid biomass and other solid fuels for their daily household cooking needs (1, 2). The fuels are typically used on unvented, simple stoves leading to levels of indoor air pollution that are among the highest ever measured (3). Studies from developing countries report average particulate concentrations that are 10 or more times higher than the U.S. Environmental Protection Agency Standards (4, 5). Exposure to these high levels of pollution has been consistently associated with acute respiratory infections (ARI) (6), the largest single-category cause of morbidity and mortality worldwide (7). It accounts for approximately 9% of the global burden of disease, 80% of which is in developing country children