Long-Term (2003-2019) Air Quality, Climate Variables, and Human Health Consequences in Dhaka, Bangladesh

Long-term trends in air quality by studying the criteria pollutants (PM2.5, PM10, CO, O-3, NO2, and SO2) and climate variables (temperature, surface pressure, and relative humidity) were depicted in this study. The 17-year (2003-2019) average values of PM2.5, PM10, CO, O-3, NO2, and SO2 were 88.69 +/- 9.76 mu g/m(3), 124.57 +/- 12.75 mu g/m(3), 0.69 +/- 0.06 ppm, 51.42 +/- 1.82 ppb, 14.87 +/- 2.45 ppb, and 8.76 +/- 2.07 ppb, respectively. The trends among the ambient pollutants were increasingly significant (p < 0.05) except for O-3 with slopes of 1.83 +/- 0.15 mu g/m(3)/year, 2.35 +/- 0.24 mu g/m(3)/year, 0.01 +/- 0.002 ppm/year, 0.47 +/- 0.03 ppb/year, and 0.40 +/- 0.02 ppb/year for PM2.5, PM10, CO, NO2, and SO2, respectively. Pearson correlations revealed a significant association among the pollutants while a noteworthy correlation was observed between ambient pollutants and surface temperature. Principal component analysis (PCA) and positive matrix factorization (PMF) have been employed collectively to examine the main sources of the pollutants. PCA revealed similar trends for PMs and CO, as well as NO2 and SO2 being equally distributed variables. PMF receptor modeling resulted in attributing four sources to the pollutants. The factors inferred from the PMF modeling were signified as vehicular emissions, road/soil dust, biomass burning, and industrial emissions. The hazard quotient (HQ) values were not antagonistic (HQ < 1) in acute exposure levels for the three age groups (infants, children, and adults) while showing significant health risk (HQ > 1) in chronic exposure for infants and children. Children are identified as the worst sufferers among the age groups, which points to low breathing levels and high exposure to traffic pollution in Dhaka, Bangladesh.