The impact of improved wood-burning stoves on fine particulate matter concentrations in rural Mexican homes

Abstract

To evaluate the impact of improved wood burning stoves on indoor air pollution, 53 homes in a rural town in Michoaca´n, Mexico, were selected from a health intervention study and monitored before and after receiving improved wood-burning stoves. Fine particulate matter F particles with aerodynamic diameter less than 2.5 mm (PM 2.5 ) F concentrations were measured in the central plaza of the community and in three microenvironments in the home (next to the stove, in the kitchen away from the stove, and outdoor patio). Forty-eight hour mean PM 2.5 concentrations in homes that burned wood in open fires were 693 mg/m 3 (95% CI: 246-1338) near the stove, 658 mg/m 3 (95% CI: 67-1448) in the kitchen away from the stove, and 94 mg/m 3 (95% CI: 36-236) on the patio. Mean ambient 24-h concentrations in the main plaza of the community were 59 mg/m 3 (95% CI: 29-92). Paired measurements before and after the installation of the Patsari improved wood-burning stove indicate a median 71% reduction in PM 2.5 concentrations near the stove and 58% reductions in kitchen concentrations, whereas patio and main plaza concentrations remain unaffected. Only 44% of participants reported to use their Patsari stoves exclusively during the transition period. Even with the predominant mixed use of the Patsari stove with open fires, estimated daily average personal exposures to PM 2.5 were reduced by 50%.

Quantification of Carbon Savings from Improved Biomass Cookstove Projects

“…CO, CH 4 , and TNMHCs were converted into CO 2 -e using 100-yr GWPs published by the IPCC (12,13). N 2 O was not included as it has been shown to be a negligible fraction of CO 2 -e emissions from biomass stoves (7,14).…”

“…A full description of the emission factor sampling methodology and QA-QC is presented in Johnson et al (8) and in the Supporting Information. Briefly, emission samples were collected over a full day of stove use into metal-coated multiple-layer Tedlar bags and analyzed for CO 2 , CO, CH 4 , and total nonmethane hydrocarbons (TNMHCs) using a Perkin-Elmer 8410 gas chromatograph (Perkin-Elmer, US) with a flame ionization detector, and a nickel catalyst methanizer (SRI Instruments, USA). A 80-100 mesh Carbosphere packed stainless steel column (Waters Associated, Inc., US) was used for CO 2 , CO, and CH 4 analysis, and a glass bead stainless steel column (Alltech, US) was used for TNMHC analysis.…”

“…To demonstrate that robust estimates of CO 2 -e savings can be obtained at reasonable cost, an integrated approach of community-based subsampling of traditional and improved stoves in homes to estimate fuel consumption and greenhouse gas emissions, combined with spatially explicit community-based estimates of the fraction of nonrenewable biomass harvesting (fNRB), was used to estimate CO 2 -e savings for 603 homes with improved Patsari stoves in Purépecha communities of Michoacán, Mexico. Mean annual household CO 2 -e savings for CO 2 , CH 4 , CO, and nonmethane hydrocarbons were 3.9 tCO 2 -e home -1 yr -1 (95% CI ( 22%), and for Kyoto gases (CO 2 and CH 4 ) were 3.1 tCO 2 -e home -1 yr -1 (95% CI ( 26%), respectively, using a weighted mean fNRB harvesting of 39%. CO 2 -e savings ranged from 1.6 (95% CI ( 49%) to 7.5 (95% CI ( 17%) tCO 2 -e home -1 yr -1 for renewable and nonrenewable harvesting in individual communities, respectively.…”

Trace gas and particle emissions from domestic and industrial biofuel use and garbage burning in central Mexico

“…The stove cuts fuel consumption "per cooking task" roughly in half so its widespread adoption could reduce the total emissions from biofuel use. The chimney provides an approximate 70% reduction in indoor air pollution (Zuk et al, 2007). Indoor air pollution is believed to be one of the major risk factors for pneumonia, which is the largest single cause of mortality globally in children under five (Smith et al, 2004;Dherani et al, 2008).…”

Concentrations of heavy metals in Eucalyptus and Pinus wood sawdust and smoke, Copperbelt province, Zambia

“…The consideration of both stove efficiency and smoke quality (Staton and Harding nd), is a necessity to the wellbeing of biomass users in woodfuel dependent households. The reduction in risks of respiratory symptoms by women in rural Mexico who switched to using Patsari improved stove demonstrates the potential to reduce the health burden related to smoke from incomplete biomass combustion process (Zuk et al 2006).…”