According to the study, in some parts of India pollution levels are more than three times higher than a typical London street
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/household-air-pollution-puts-3-billion-risk
[2] http://admin.indiaenvironmentportal.org.in/category/author/teena-thacker
[3] http://admin.indiaenvironmentportal.org.in/category/newspaper/asian-age-new-delhi
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/india
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/indoor-air-pollution
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/health-effects
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/who
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/population
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/air-pollution
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/air-quality-and-health