The seemingly crisp, fresh air inhaled inside the sanitised and cool environs of metro premises or air-conditioned car may actually be teeming with respirable pollutants.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/air-pollutants-may-enter-metro-premises-cars-rooms-experts
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/ndtv
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/air-pollution
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/indian-institute-technology-iit
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/delhi
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/pm-25
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/respiratory-diseases
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/health-effects