Change in household fuels dominates the decrease in PM _2.5 exposure and premature mortality in China in 2005–2015

Significance

The Chinese government has taken efforts to tackle the nation’s severe ambient fine particle (PM _2.5) pollution. Our results suggest that reduced household solid-fuel consumption was the leading contributor to the rapid decrease in the integrated exposure to ambient and household PM _2.5 pollution during 2005–2015, even though there was no explicit household control policy. In contrast, the emission reductions from power plants, industry, and transportation contributed much less to the decrease of integrated exposure. Clean household heating fuels have become part of recent control policies in northern China, but such policy would be strengthened if extended to heating and cooking countrywide since shift of the remaining household solid fuels to clean fuels could additionally avoid an estimated half-million premature deaths annually.

Abstract

To tackle the severe fine particle (PM _2.5) pollution in China, the government has implemented stringent control policies mainly on power plants, industry, and transportation since 2005, but estimates of the effectiveness of the policy and the temporal trends in health impacts are subject to large uncertainties. By adopting an integrated approach that combines chemical transport simulation, ambient/household exposure evaluation, and health-impact assessment, we find that the integrated population-weighted exposure to PM _2.5 (IPWE) decreased by 47% (95% confidence interval, 37–55%) from 2005 [180 (146–219) μg/m ³] to 2015 [96 (83–111) μg/m ³]. Unexpectedly, 90% (86–93%) of such reduction is attributed to reduced household solid-fuel use, primarily resulting from rapid urbanization and improved incomes rather than specific control policies. The IPWE due to household fuels for both cooking and heating decreased, but the impact of cooking is significantly larger. The reduced household-related IPWE is estimated to avoid 0.40 (0.25–0.57) million premature deaths annually, accounting for 33% of the PM _2.5-induced mortality in 2015. The IPWE would be further reduced by 63% (57–68%) if the remaining household solid fuels were replaced by clean fuels, which would avoid an additional 0.51 (0.40–0.64) million premature deaths. Such a transition to clean fuels, especially for heating, requires technology innovation and policy support to overcome the barriers of high cost of distribution systems, as is recently being attempted in the Beijing–Tianjin–Hebei area. We suggest that household-fuel use be more highly prioritized in national control policies, considering its effects on PM _2.5 exposures.