Potential reductions in premature mortality attributable to PM by reducing indoor pollution: A model analysis for Beijing-Tianjin-Hebei of China.

BACKGROUND

China has one of the highest PM (particulate matter with an aerodynamic diameter smaller than 2.5 μm) pollution levels in the world. It might still be long before air quality reaches the National Class II standard of 35 μg/m.

OBJECTIVE

We aim to estimate the potential reduction in premature mortality by reducing indoor PM levels in the Beijing-Tianjin-Hebei (BTH) region and compare it with reducing outdoor levels.

METHODS

We combined PM transport model and the Global Burden of Disease (2016) methodology to estimate potential reductions in premature mortality attributable to PM by reducing indoor PM to National Class I standard of 15 μg/m, and compared with reducing outdoor PM to Government 2020 Interim target of 64 μg/m or National Class II standard of 35 μg/m.

RESULTS

A total of 74,000 (95% confidence interval (CI): 43,000-111,000) premature deaths were attributable to PM exposure in 2013. Thirty percent, or 22,000 (95% CI: 17,000-32,000) deaths, would have been averted if indoor PM had reached the National Class I standard. The benefit is greater than that from reaching the Government 2020 Interim target for outdoor PM [22%, or 16,000 (95% CI: 12,000-23,000), deaths], although still smaller than that from reaching the National Class II standard [42%, or 31,000 (95% CI: 24,000-45,000), deaths].

CONCLUSIONS

Reaching the National Class I level of indoor PM at current outdoor pollution levels could bring considerable health benefits, which are comparable to those from reaching the Government 2020 Interim target for outdoor PM.

MAIN FINDINGS

The avertable premature deaths gained from cleaning indoor PM to National Class I standard level would be greater than reducing outdoor PM to Government 2020 Interim target.