Elemental characterization of PM10 and PM2.5 and exposure risk assessment: Auto-repair garage

This study represents a crucial first step in developing a profound understanding of the existence and nature of ambient air quality in auto-repair garages (ARGs). In this study, comprehensive monitoring of PM 10 , PM 2.5 , NO X , and SO 2 levels was performed in ARG. To gain comprehensive insights into their elemental composition, inductively coupled plasma-mass spectroscopy was performed on PM 10 and PM 2.5 filters and 20 elements were identified (transition metals: Ag, Cd, Cr, Cr-VI, Cu, Fe, Mo, Mn, Ni; post-transition metals: Al, Hg, Pb, Sn, Zn; metalloids: As, B, Sb; alkaline earth metals: Ba and Na; reactive non-metal: Se) in ARG. The maximum measured concentration for PM 10 was 235.42 µg m −3 , while for PM 2.5 , it peaked at 80.42 µg m −3 , underscoring the severity of PM exposure from ARG workers. Elemental analysis revealed that elements bound to PM 10 and PM 2.5 contain significant proportions of Al (15–17%), B (24–28%), Ba (32%), Fe (2–4%), and Zn (23%). However, the transition metals exhibited higher concentration compared to post-transition metals, alkaline earth metals, reactive non-metals and metalloids. An integrated risk assessment was carried out to assess the potential risks of exposure to these pollutants. The combined carcinogenic risks (ECRs) for As, Cd, Cr (VI), Ni, and Pb in PM 10 and PM 2.5 -bound heavy metals were 2.99 × 10 –4 and 6.94 × 10 –4 , respectively, suggesting potential cancer incidence of 3–7 cases per 10,000 people due to exposure to toxic heavy metals in ARG's PM-bound elements indicating significant concerns to ARG workers.