气候变化领域集成服务门户

BACKGROUND: Emissions from solid fuels used for cooking cause similar to 4 million premature deaths per year. Advanced solid-fuel cookstoves are a potential solution, but they should be assessed by appropriate performance indicators, including biological effects.

OBJECTIVE: We evaluated two categories of solid-fuel cookstoves for eight pollutant and four mutagenicity emission factors, correlated the mutagenicity emission factors, and compared them to those of other combustion emissions.

METHODS: We burned red oak in a 3-stone fire (TSF), a natural-draft stove (NDS), and a forceddraft stove (FDS), and we combusted propane as a liquified petroleum gas control fuel. We determined emission factors based on useful energy (megajoules delivered, MJd) for carbon monoxide, nitrogen oxides (NOx), black carbon, methane, total hydrocarbons, 32 polycyclic aromatic-hydrocarbons, PM2.5, levoglucosan (a wood-smoke marker), and mutagenicity in Salmonella.

RESULTS: With the exception of NOx, the emission factors per MJ(d) were highly correlated (r >= 0.97); the correlation for NOx with the other emission factors was 0.58-0.76. Excluding NOx, the NDS and FDS reduced the emission factors an average of 68 and 92%, respectively, relative to the TSF. Nevertheless, the mutagenicity emission factor based on fuel energy used (MJ(thermal)) for the most efficient stove (FDS) was between those of a large diesel bus engine and a small diesel generator.

CONCLUSIONS: Both mutagenicity and pollutant emission factors may be informative for characterizing cookstove performance. However, mutagenicity emission factors may be especially useful for characterizing potential health effects and should be evaluated in relation to health outcomes in future research. An FDS operated as intended by the manufacturer is safer than a TSF, but without adequate ventilation, it will still result in poor indoor air quality.