Ambient PM2.5 exposure and premature mortality burden in the holy city Varanasi, India.

More than 3 million population residing in the holy city Varanasi and sub-urban areas is exposed to very high level of fine particulate matter (PM2.5) from various sources. Continuous monitoring by Central Pollution Control Board started only in 2015; therefore what was the pollution level in the past and how it has changed over the years are not known. We use MODIS aerosol products to infer PM2.5 and examine 15-year climatology. Data shows a rapid (1.5-3% per year) increase in PM2.5 in the last 15 years and high (87% days in a year) persistence of PM2.5 above the national air quality standard. It translates to a burden of 5700 (2800-7500) annual premature deaths (0.16% of the population), of which 29%, 18%, 33%, 19% and remaining 1% are attributed to ischemic heart disease, stroke, chronic obstructive pulmonary disease, acute lower respiratory infection and lung cancer respectively. If the region achieves the Indian (WHO) air quality standard, 1900 (3800) premature deaths can be avoided every year.