ABSTRACT
Several air quality parameters such as particulate matter (PM), ozone (O3), nitrogen dioxide (NO2), sulphur dioxide (SO2), and carbon monoxide (CO) are considered as the major pollutants which can impose a significant threat to human health and surrounding environment. In this study, seasonal and temporal variations were analyzed for both gaseous air pollutants and particulate matter to investigate the trend analysis of ambient air quality of Chattogram city, a commercial hub of Bangladesh. Air quality data for six selected parameters (PM2.5, PM10, CO, SO2, NO2, and O3) were collected from Continuous Air Monitoring Stations (CAMS) during the period 2013 to 2021 for each pollutant. Air Quality Index (AQI) for each tested pollutant was determined as well as pollution level sharing among the pollutants was also investigated in this work. Results of this study showed that particulate matters (PM2.5 and PM10) were the most responsible pollutants that contributed significantly to air pollution levels in the city. The yearly average AQI was observed to be in the caution (unhealthy for sensitive groups) (100-150) category during the period from 2013 to 2021. Trend analysis showed that there is an ups and downs trend in the AQI level in the city that may be triggered by some interventions taken and Covid-19 pandemic situations. Overall, seasonal variation had a considerable effect on the concentration of pollutants. For each year, the highest concentration of PM2.5 and PM10 was recorded in winter season while the lowest was reported in monsoon season. This study will assist the researchers and policymakers in taking the required steps to take preventive measures in reducing air pollution levels for the studied area. © 2023 Author(s).