Decadal-Scale Assessment of the Impact of Household Fuel Use on PM2.5 exposure and Public Health in China

To tackle the severe fine particle (PM_2.5) pollution in China, the Chinese government has implemented substantial emission control policies since 2005. However, until recently, little attention has been paid to household fuel burning, which could make remarkable contribution to PM_2.5 exposure through both ambient air pollution (AAP) and household air pollution (HAP). Here we estimate the integrated population-weighted exposure to PM_2.5 (IPWE), which integrates the human exposure to both AAP and HAP, in China during 2005-2015, and evaluate the contribution from household fuel use. We establish IPWE based on simulation using the Community Multi-scale Air Quality model with two-dimensional Volatility Basis Set (CMAQ/2D-VBS) and additional indoor PM_2.5 exposure among household solid-fuel users. During 2005-2015, IPWE in China decreased by 47% (95% confidence interval, 37-55%) from 2005 [180 (146-219) mg/m³] to 2015 [96 (83-111) mg/m³]. The IPWE attributed to household fuel use decreased by 76 (48 to 109) mg/m³, which accounts for 90% (86-93%) of the total IPWE reduction during this period. This decrease is primarily induced by rapid urbanization and improved incomes rather than specific control policies. Among IPWE, the reductions in AAP and HAP due to household fuel are about 7 mg/m³ and 69 mg/m³, respectively. The dramatic reduction in IWPE attributed to household fuel use could translate into 0.40 (0.25-0.57) million avoided premature deaths. The IPWE would be further reduced by 63% (57-68%) if the remaining household solid fuels were replaced by clean fuels, which would avoid additional 0.51 (0.40-0.64) million premature deaths. Such a transition to clean fuels, especially for heating, requires technology innovation and substantial policy support to overcome the barriers of high economic cost and distribution system construction. We suggest that household-fuel use be prioritized in national control policies considering its effects on PM_2.5 exposure.