Local incomplete combustion emissions define the PM2.5 oxidative potential in Northern India

The oxidative potential (OP) of particulate matter (PM) is a major driver of PM-associated health effects. In India, the emission sources defining PM-OP, and their local/regional nature, have yet to be established. To address this gap, we determined the geographical origin, sources of PM, and its OP at five Indo-Gangetic Plain (IGP) sites inside and outside Delhi. Our findings reveal that although uniformly high PM concentrations were recorded across the entire region, local emission sources and formation processes dominate PM pollution. PM-OP is overwhelmingly driven by OA from incomplete combustion of biomass and fossil fuels, including traffic. These findings suggest that addressing local inefficient combustion processes can effectively mitigate PM health exposure in Northern India., The data of five main figures is provided.
Raw data used in the study is also provided.
The data was collected using different advanced mass spectrometric techniques and relevant softwares were used to analyze the data. Details are provided in the materials and methods section., , # Local incomplete combustion emissions define the PM2.5 oxidative potential in Northern India

Main figures:

Fig. 1. Summary of fine particulate matter (PM2.5) chemical composition and source contributions. 
Figure 1b. The averaged relative mass contribution of different chemical constituents (here, EC is elemental carbon and OA is organic aerosols) to PM2.5 mass are shown for warm and cold period. Next, we represent the contribution of OA sources (CPOA- Cold season primary organic aerosol, BBOA- Biomass burning oragnic aerosol, UOOA- Urban oxygenated organic aerosol, COOA- cold oxygenated organic aerosol and HOA- Hydrocarbon-like organic aerosol) to OA. Further, contribution of different OA and elemental sources to oxidative potential (AAv, DTTv and DCFHv) are shown.
Figure 1c. The non-fossil fraction of diffferent OA sources, OA and EC in warm and cold period are shown.

Fig. 2. Spatial and temporal variation in fine particulate matter (PM2.5) and its species.
The right hand panel s...