Health risk assessment of heavy metals and poly-aromatic hydrocarbons in particulate matter adsorbed by indoor air purifiers

Abstract

Particulate matter (PM) adsorbed by air purifiers, normally used in residential buildings, was collected and analysed by this study. The concentrations of eight heavy metals and 16 poly-aromatic hydrocarbons (PAHs) in PM were determined by inductively coupled plasma-optical emission spectroscopy (ICP-OES) and gas chromatography-mass spectroscopy (GC-MS). The health risk of heavy metals and PAHs was assessed using the health assessment model recommended by the US Environment Protection Agency (EPA). The results showed that the total concentrations of heavy metals during the heating period and non-heating period were 771.27 mg/kg and 441.10 mg/kg, respectively. The carcinogenicity and non-carcinogenicity of chemicals found are higher during the heating period than the non-heating period. The exposure of children was higher than that of adults. Eight heavy metals would pose non-carcinogenic risks for children, but four of these would pose carcinogenic risks for adults and children. The total concentrations of 16 PAHs during the heating period and non-heating period were 106.69 μg/kg and 68.72 μg/kg, respectively. Total toxicity equivalents (TEQs) were 16.37 μg/kg and 9.20 μg/kg, respectively. Among them, 4-rings PAHs accounted for the highest proportion, followed by 5-rings PAHs and 6-rings PAHs. The proportion of 2-rings and 3-rings PAHs were the lowest. 16 PAHs could pose a high carcinogenic risk to adults and children during the heating period, and there was a potential carcinogenic risk during the non-heating period.