Premature Mortality Due to PM2.5 Over India: Effect of Atmospheric Transport and Anthropogenic Emissions

The annual premature mortality in India attributed to exposure to ambient particulate matter (PM2.5) exceeds 1 million (Cohen et al., 2017, https://doi.org/10.1016/S0140-6736(17)30505-6). Studies have estimated sector-specific premature mortality from ambient PM2.5 exposure in India and shown residential energy use is the dominant contributing sector. In this study, we estimate the contribution of PM2.5 and premature mortality from six regions of India in 2012 using the global chemical-transport model. We calculate how premature mortality in India is determined by the transport of pollution from different regions. Of the estimated 1.1 million annual premature deaths from PM2.5 in India, about similar to 60% was from anthropogenic pollutants emitted from within the region in which premature mortality occurred, similar to 19% was from transport of anthropogenic pollutants between different regions within India, similar to 16% was due to anthropogenic pollutants emitted outside of India, and similar to 4% was associated with natural PM2.5 sources. The emissions from Indo Gangetic Plain contributed to similar to 46% of total premature mortality over India, followed by Southern India (13%). Indo Gangetic Plain also contributed (similar to 8%) to the most premature mortalities in other regions of India through transport. More than 50% of the premature mortality in Northern, Eastern, Western, and Central India was due to transport of PM2.5 from regions outside of these individual regions. Our results indicate that reduction in anthropogenic emissions over India, as well as its neighboring regions, will be required to reduce the health impact of ambient PM2.5 in India.