Airborne heavy metals penetrating through face masks: A manikin respiratory model study and associated health risks

• The first study of heavy metals in particulate matter penetrating respiratory masks. • The use of leaked heavy metal in size fractionated PM to assess efficiency of masks. • The highest metals penetration rate in PM 0.5 were observed for surgical mask. • LCR of Cr exceeded the maximum acceptable level of 1.00E-04 PM in all types masks. • None of the evaluated masks effective protection against heavy metal inhalation. The extensive use of face masks as personal protection to reduce exposure to inhalation particulate matter (PM), particularly PM-bound toxic metals has become increasingly important. However, the effectiveness of these commercial face masks in filtering fine PMs containing heavy metals remains questionable. The aim of this study is to investigate the penetration of heavy metals in size-fractionated particulate matters (PM 2.5, PM 1 and PM 0.5 ) through various face masks, including surgical, N95, and FFP2 and assess the associated health risks. The respirable PM collected through face masks fitted on a dummy model. Concentrations of metals including Zn, V, Se, Sb, Pb, Ni, Mn, Fe, Cu, Cr, Co, Cd, Ca, Bi and Al was carried out by ICP-MS. Health risk were assessed using EPA recommended model. Based on the results the surgical and FFP2 masks exhibited the highest and lowest penetration of metals, especially PM 0.5 , respectively . The HQ s of Al, Cr, Mn and Ni in PM 0.5 and PM 2.5 as well as Ni in PM 1 that passed through surgical respiratory mask were exceeded the safety limits (1). Among three carcinogenic metals, Cr in PM 0.5 , PM 1 and PM 2.5 was identified as the most significant health risk, exceeding acceptable carcinogenic levels for all types of masks. While surgical mask showed the poorest performance in capturing metals in PMs ranges, the N95 and FFP2 also could not provide complete protection. Based on the finding of risk assessment, none of the evaluated masks provided complete protection against these toxic elements, suggesting a need for more effective respiratory protection.