This study monitoring and assessment of air pollutants, including lead and nickel trace metals, gases such as sulphur dioxide (SO2) and nitrogen dioxide (NO2), and respirable suspended particulate matter (PM10) and fine particulate matter (PM2.5), were done at nine locations that were divided into three categories: residential, commercial, and industrial of the ambient air quality in the city of the post-monsoon. With an average of 148.9 µg m-3, the 24-hour concentrations of PM10 ranged from 58.5 to 337.8 µg m-3, whereas the 24-hour concentrations of PM2.5 ranged from 32.5 to 118.4 µg m-3, with an average of 70.5 µg m-3. At every location, the mean concentrations of PM10 exceeded the allowable threshold of 100 µg m-3. While PM2.5 levels, with the exception of Aliganj, Vikas Nagar, and Chowk, exceeded the 60µg m-3 national limit. Pb and Ni, which are PM10 trace elements, range from 0.0028 to 0.0370 µg m-3, with an average of 0.0147 µg m-3 for Pb and 1.30 to 11.75 µg m-3, with an average of 6.62 µg m-3 for Ni. During a 24-hour period, the levels of SO2 varied between 7.9 and 57.7 µg m-3, with an average of 20.8 µg m-3. Conversely, the levels of NO2 varied between 9.3 and 89.0 µg m-3, with an average of 37.8. Between µg m-3 the post-monsoon of 2022 and 2023, SO2 concentrations declined by 16.0% and NO2 values increased by 22.0%, respectively. On the other hand, average SO2 and NO2 levels were significantly lower than the 80µg m-3permitted limits set by the CPCB (NAAQS-2009).
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