Source apportionment, ecological, and human health risks of toxic metals in road dust of densely populated capital and connected major highway of Bangladesh

Abstract

This study investigates pollution levels, source apportionment, ecological and human health risks associated with toxic metals (Pb, As, Hg, Cr, and Cd) in road dust from the most populated Dhaka city and a connected major highway in Bangladesh. The mean concentration of Pb, Hg, and Cd were 1.3, 29.3, and 13.2 times higher than their corresponding background values with spatially uneven distribution all over the study area. Metal pollution indices, the geoaccumulation index (I geo ), NIPI, PI, indicated extreme contamination at many sites depending on local environmental factors. The potential ecological risk (E i r ) revealed that 84% and 54% of samples showed the extreme ecological risk for Hg and Cd pollution, respectively. On the other hand, the potential ecological risk index (PERI) and nemerow integrated risk index (NIRI) showed that most sampling sites suffered high to extreme ecological risk. Source apportionment using positive matrix factorization (PMF) identi ed coal combustion and gasoline (50.14%), tra c exhaust (35.26%), and industrial and agriculture activity (14.60%) were the main source of toxic metals of the study area. Non-carcinogenic health risk indicated that adults are more vulnerable than children, and hazard index (HI) of Hg for both age groups and Cd for adults were signi cantly higher than the safe level. The carcinogenic risk (CR) levels of toxic metals were acceptable (10 − 6 to 10 − 4 ), although the maximum limit of Cr for children and As for adults was close to the unacceptable limit (10 − 4 ). Continual exposure to toxic metals through road dust might develop lifetime cancer risk in local inhabitants.

Zoning of Dust Heavy Metals in Arak Plain Using Pollution Indicators and Geographic Information System (GIS)

“…The study revealed severe pollution in many sampling sites, primarily attributed to local environmental factors. 29 These studies provide additional evidence of the impact of human activities on metal pollution in various regions, highlighting the importance of pollution indices in assessing and understanding the sources and levels of pollution.…”

Elevated levels of environmental radioactivity in fluvial sediment: origin and health risk assessment

“…Therefore, these ve extracted components were included in the widely used EPA-PMF 5.0 model to infer the NORMs' and elements' source prole contribution and provenance. 34,64,67,[100][101][102] As demonstrated in Fig. 5a, factor-1 is predominantly characterized by 61.4, 48.7, 47.5, and 41.4% of the Eu, Hf, P HREE, and Yb concentrations, respectively.…”

“…where the amount of element j of sample i is represented as x ij , the quantication of factor k to the sample i is referred to as g ik , the contribution of element j in factor k is denoted by f kj , the abundance of residues for the j element in the i sample is e ij , and the factor number is indicated by p. Non-negative factor contributions are required for an accurate interpretation of the operation. 64 For the PMF model to work, g ik and f kj must remain constant as the objective function and Q must be reached at its lowest. The Q value signies modelling quality.…”

Pollution and Health Risk Assessment of Hazardous Elements in Surface dust along an Urbanization Gradient

“…Increasing demand for metals in industries and urbanization process have strongly disturbed the natural geochemical cycling of the urban ecosystem [5,6], and urbanization processes can result in the accumulation of HEs in surface dust in urban ecosystems [7,8]. Traffic exhaust, incinerators, industrial waste, and the atmospheric deposition of dust and aerosols have continuously added HEs to the urban environment [9], and HEs accumulate in the human body can cause irreversible damage to human health [10,11]. Therefore, HEs in surface dust can serve as a comprehensive indicator of the quality of the urban environment [12].…”