Human Exposure to Potentially Toxic Elements in Household Dust: Spatial Distribution, Contamination Status, Positive Matrix Factorization, and Monte Carlo Simulation‐Based Probabilistic Health Risk Assessment

Indoor dust pollution is a serious environmental concern, especially when it carries potentially toxic elements (PTEs) that can harm human health. This study aimed to measure concentrations of PTEs (Cr, Mn, Ni, Co, Cu, Zn, Cd, and Pb) using ICP-OES in household dust collected from 30 residential sites in Lahore, Pakistan. This study combined positive matrix factorization (PMF) for source apportionment with Monte Carlo simulation to estimate the probabilistic human health risk. The concentration (mean ± SD) of analyzed PTEs found Zn (528.74 ± 180.75) at the highest concentration, followed by Mn (250.60 ± 17.18), Cu (50.32 ± 21.56), Pb (57.30 ± 15.98), Cr (59.52 ± 17.68), Ni (32.45 ± 6.72), Co (10.21 ± 2.84), and Cd (4.22 ± 2.78). Average daily dose (ADD), hazard quotient (HQ), hazard index (HI), and carcinogenic risk (CR) were also calculated to gauge potential impacts on human health. The contamination factor (CF) and geo-accumulation index (I_geo) showed that household dust carried severe contamination overall, with the highest concern tied to Cd. HI values for all elements were less than 1, indicating no non-carcinogenic health risk for adults and children. The LCR value for Cr through various exposure pathways for children was determined to be 5.87 × 10^-2, while the corresponding values for Ni were 1.09 × 10^-2 for children and 1.17 × 10^-3 for adults. This study indicates that improvements in management practices of indoor air quality will minimize harmful exposures. Children are a more sensitive population, and there is an urgent need for indoor exposure control policies.