Elemental analysis in surface soil and dust of roadside academic institutions in Dhaka city, Bangladesh and their impact on human health

Abstract The increasing industrial activities, number of vehicles on road and population in large cities causes the contamination of air in urban environment, and eventually affect human health. Therefore, the aim of this study was to collect soil and dust samples from twelve roadside academic institutions in Dhaka City, Bangladesh. One of the twelve sites is control site for this study. The elemental (Ca, Fe, K, Ti, Sr, Zn, Zr, Rb, Cr, Ni, Pb and Cu) concentration in soil and dust samples were analyzed by XRF technique. The metals concentration in dust and soil samples followed the following order: Fe > Ti > Sr > Zn > Zr > Rb > Pb > Cu, and Fe > Ti > Zr > Sr > Rb > Zn > Cu > Pb > As, respectively. As expected, the most elemental concentration at the control site, which was situated inside a village and ~ 1 km far away from the road, was lower compared with those in soil and dust samples. Average As concentration (16.52 mg/kg) in soil was observed to be three times higher than its background value. The concentration of Pb in the dust sample of a school at Sadarghat (136.04 mg/kg) was significantly higher than the other sites. We observed that the mean concentration for most of the metals had a higher concentration than the background values set by Chinese Environmental Protection Administration (CEPA), except for K and Zr. Soil samples were analyzed to determine the percentage of organic matter by dry combustion technique, and the average amount of organic matter in soil samples was 1.42%. Conversely, the contamination levels of heavy metals were assessed based on the geo-accumulation index (Igeo), enrichment factor (EF) and contamination factor (CF). Subsequently non-carcinogenic health risk was determined using lifetime average daily dose (LADD). The non-carcinogenic health risk was found to be more prominent for children than that for adults. No significant carcinogenic health risk was found in the study area.