Health risk assessment of PM10 bound heavy metals in the ambient air of Gurugram urban area

Abstract

Gurugram is a rapidly developing corporate and industrial hub facing severe air pollution. In this study, ambient particulate matter (PM₁₀) bound heavy metals, their source apportionment, and potential human health risks were investigated in the urban area of Gurugram, Haryana. A total of 56 samples were collected using a respirable dust sampler (APM 460) with Whatman filter paper (EPM 2000) from October 2022 to April 2024, excluding monsoon months. The annual average PM₁₀ concentration (169.5 μg/m³) was about 11 times higher than WHO (2021) guidelines and 3 times higher than the NAAQS given by CPCB. Seasonal variation was evident, with the highest levels in post-monsoon, followed by winter. Heavy metals (Cr, Mn, Ni, Pb, Cd, Cu, Fe) were analysed using ICP-MS, with Fe (10.9 μg/m³) being the most abundant. Enrichment factor analysis showed high Pb levels, indicating anthropogenic sources. Human health risk assessment revealed that the Hazard Index (HI) values exceeded the threshold limit (=1) for all three exposure pathways. This finding indicates that the population residing in the study area is prone to non-carcinogenic risks due to PM₁₀-bound heavy metals. The Excess Cancer Risk (ECR) values for Hazard Index (HI) were found to be above the safe limit (10⁻⁴ – 10⁻⁶). Consequently, this suggests that exposure to PM₁₀ in the study area may lead to an elevated risk of developing cancer over a lifetime, thereby underscoring the potential public health threat posed by these heavy metals. The conclusions demonstrate that tougher measures and stronger efforts must be taken to tackle heavy metal pollutants and the risks they pose to health.