With densely-populated areas in the city, especially Punjabi Bagh and R.K.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/high-ozone-levels-raise-alarm
[2] http://admin.indiaenvironmentportal.org.in/category/author/bindu-shajan-perappadan
[3] http://admin.indiaenvironmentportal.org.in/category/newspaper/hindu-new-delhi
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/delhi
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/ozone-layer
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/respiratory-diseases
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/carbon-monoxide
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/environmentalists
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/nitrogen-dioxide
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/centre-science-and-environment-cse
[11] http://admin.indiaenvironmentportal.org.in/category/thesaurus/pollution
[12] http://admin.indiaenvironmentportal.org.in/category/thesaurus/atmosphere-and-ozone-layer