Characterization of ambient PM2.5 at a pollution hotspot in New Delhi, India and inference of sources

Research output: Contribution to journalArticle

Authors

  • Pallavi Pant
  • Anuradha Shukla
  • Steven D. Kohl
  • Judith C. Chow
  • John G. Watson

Colleges, School and Institutes

External organisations

  • Department of Environmental Sciences / Center of Excellence in Environmental Studies, King Abdulaziz University, PO Box 80203, Jeddah, 21589, Saudi Arabia

Abstract

Ambient PM2.5 samples were collected at a high-traffic location (summer and winter 2013) and characterized for a large suite of elemental and organic markers. Concentrations were found to exceed the Indian PM2.5 air quality standard on several occasions, especially in the winter. Winter concentrations of several individual tracer species were several fold higher compared to summer, particularly for some PAHs and trace metals. Enrichment factors relative to crustal material showed significant enrichment for elements such as Ti, Sb, Pb and As, although Ba, often used as a marker for non-exhaust emissions from traffic was not found to be enriched appreciably. Crustal material was found to be an important contributor in the summer (14.3%), while wood burning (23.3%), nitrates (12.4%) and chlorides (12.3%) were found to be major contributors in winter. The contribution of road traffic exhaust emissions was estimated to be 18.7% in summer and 16.2% in winter. Other combustion sources (wood and other biomass/waste/coal) were found to be a significant source in winter, and contribute to the higher concentrations. Secondary sulphates, nitrates and chloride (the latter two in winter) and organic matter also contribute substantially to PM2.5 mass.

Details

Original languageEnglish
Pages (from-to)178-189
Number of pages12
JournalAtmospheric Environment
Volume109
Early online date27 Feb 2015
Publication statusPublished - 1 May 2015

Keywords

  • Molecular markers, Traffic, India, Mass closure, Particulate matter