How Bad is the Outdoor Air Pollution in India?

How Bad is the Outdoor Air Pollution in India?

Nature of air pollution, emission sources, and management in the Indian cities
Journal article in Atmospheric Environment (2014) Download
The World Health Organization (WHO) studied publicly available air quality data from 1100 cities across the world and listed 27 cities in India among the top 100 cities with the worst air quality in the world, with Ludhiana, Kanpur, Delhi, and Lucknow listed in the top 10 cities. This is based on the ambient PM10 concentrations data available from the world cities between the period of 2008-10.
The dark color bars in the figure to the right, highlight the Indian cities.
The WHO guideline for annual average PM10 concentrations is 20 micro-g/m3

Air pollution is a complex mixture of pollutants with sources ranging from fossil fuel burning in transportation, power generation, industries, and domestic sectors. In all the cities, transport remains an important source of ambient air pollution – from direct vehicle exhaust emissions and indirect re-suspension of dust due to constant movement of vehicles on the road. In 2011, the Ministry of Environment and Forests (MoEF) published the results of a source apportionment study for six cities in India (Bangalore, Chennai, Delhi, Kanpur, Mumbai, and Pune).
Link to MoEF website
Commentary on the source apportionment results for Delhi
A illustrated explanation of what is source apportionment
The global burden of disease (GBD) study quantified the trends of more than 200 causes of deaths for the period of 1990-2010 and listed outdoor air pollution among the top 10 causes of deaths for India (published in the Lancet series, December 2012). For India, total premature mortality due to outdoor particulate matter (PM) pollution is estimated at 627,000 – with most of these impacts felt in the cities. This GBD assessment utilized a combination of ground measurements (where available) from the cities and substituted the remaining urban and rural area with data retrieved from satellite measurements. Most notable of the health impacts resulting in premature deaths and those linked to ambient air pollution include chronic obstructive pulmonary disease, lower respiratory infections, cerebrovascular disease, ischemic heart disease, and cancers of trachea, bronchitis, and lung.
Link to Lancet Series on GBD assessment

The morbidity and mortality burden is particularly costly for the government in terms of work days lost, lost productivity, and loss in terms of gross domestic product. Since, the most health impacts occur within a year or two of exposure, reducing the ambient pollution from sources like transport and industries has an immediate benefit.
This GBD assessment utilized a combination of ground measurements (where available) from the cities and substituted the remaining urban and rural area with data retrieved from satellite measurements for PM2.5 pollution. PM2.5 refers to particulate matter less than 2.5mm in aerodynamic diameter. A sample of the satellite results is presented below.

Link to the extracted ground level PM2.5 data from satellite measurements.