Black Carbon vs Carbon Monoxide: Assessing the Impact on Indian Urban Cities

In this study, we concurrently determined the combined ratio of black carbon (BC) and carbon monoxide (CO) in two distinct cities in eastern India: Jamshedpur (JSR) and Kharagpur (KGP). The investigation spanned from October 2019 to January 2020, revealing BC mass concentrations of 10.06 (± 1.59) µg m −3 in JSR and 5.49 (± 1.15) µg m −3 in KGP. Additionally, the average CO concentrations measured were approximately 913.63 (± 217.85) ppbv in JSR and 507.31 (± 125.06) ppbv in KGP. Analysis of GIOVANNI NASA satellite data highlighted elevated concentrations of BC and CO in the Indo-Gangetic Plain (IGP), the foothills of the central Himalayas, and the eastern region of India. Utilizing diagnostic ratio analysis to attribute the sources of BC, we found that wood-burning contributed more significantly to the BC levels in KGP compared to JSR. The higher overall aerosol concentration in JSR was attributed to the prevalence of numerous industries and heavy traffic. Pearson correlation analysis indicated substantial correlations between BC–CO and BC–PM 2.5 , with correlation coefficients of r 2 = 0.65 and r 2 > 0.96, respectively. These results underscore the need for significant changes to be implemented, such as transitioning to alternative appliances that do not rely on fossil fuels. By adopting cleaner and more sustainable energy sources, we can effectively mitigate the adverse impacts of BC, PM2.5, and CO emissions on air quality and public health. Air back-trajectory analysis unveiled the predominant northward transmission of pollution from northern India. Additionally, air masses originating from neighboring countries such as Pakistan, Nepal, Bangladesh, and Bhutan also contributed to the pollution levels. Health risk assessments revealed estimated non-cancerous particulate health risks (Npsc) ranging from 6.27 to 25.6 in JSR and 2.02 to 8.28 in KGP, emphasizing potential health implications associated with BC exposure in the two cities.