Unveiling the elemental composition, sources and health impacts of PM10 over the central Indo-Gangetic plain (IGP) of India

This study investigates the PM<INF>10</INF> pollution in the central Indo-Gangetic plain (IGP) of India from February 2018 to December 2019, revealing an annual average PM<INF>10</INF> concentration of 193 +/- 65 mu g m-<SUP>3</SUP>. Seasonal concentrations peaked in winter season followed by summer, post-monsoon and monsoon seasons. WD-XRF identifying 35 elements, including major elements like Si, Al, Ca, and Fe, which contributed 18% to PM<INF>10</INF> concentrations. The enrichment factor analysis indicates that the Rb, Sr, and Na originate from natural sources, while Fe, Al, Mn, K, Ca, Mg, and Zr have both natural and anthropogenic sources. The remaining elements are primarily of anthropogenic origin. Source apportionment through Principal Component Analysis (PCA) revealed the six key PM<INF>10</INF> sources: mixed type (dust+biomass burning, 42%), vehicular (24%), industrial (15%), combustion (7%), agricultural activities (6%), and fossil fuel combustion (6%). Local sources from the northwest (NW) and west (W) directions were dominant, with smaller contributions from trans-boundary regions like Afghanistan and Pakistan. Health risk assessments highlighted non-carcinogenic risks from Mn for adults and children, with additional risks from Al and Cr for children, and carcinogenic risks from Cr for adults. The risk of Al, Cr and Mn in Varanasi are likely driven by combustion related activities, as Cr and Mn in PM<INF>10</INF> are commonly associated with industrial and vehicular emission sources.