Short-term inhalation exposure evaluations of airborne antibiotic resistance genes in environments

● Standardised comparison confirmed that livestock and hospitals are AARGs hotspots. ● Correlations between AARGs with MGEs and bacteria are strong in suburbs in China. ● A new AARGs exposure calculation that used short-term inhalation was proposed. ● AARGs short-term intakes in livestock and hospital are 2.5 × 10 5 and 9.3 × 10 5 copies. Antibiotic resistance is a sword of Damocles that hangs over humans. In regards to airborne antibiotic resistance genes (AARGs), critical knowledge gaps still exist in the identification of hotspots and quantification of exposure levels in different environments. Here, we have studied the profiles of AARGs, mobile genetic elements (MGEs) and bacterial communities in various atmospheric environments by high throughput qPCR and 16S rRNA gene sequencing. We propose a new AARGs exposure dose calculation that uses short-term inhalation (STI). Swine farms and hospitals were high-risk areas where AARGs standardised abundance was more abundant than suburbs and urban areas. Additionally, resistance gene abundance in swine farm worker sputum was higher than that in healthy individuals in other environments. The correlation between AARGs with MGEs and bacteria was strong in suburbs but weak in livestock farms and hospitals. STI exposure analysis revealed that occupational intake of AARGs (via PM 10 ) in swine farms and hospitals were 110 and 29 times higher than in suburbs, were 1.5 × 10 4 , 5.6 × 10 4 and 5.1 × 10 2 copies, i.e., 61.9%, 75.1% and 10.7% of the overall daily inhalation intake, respectively. Our study comprehensively compares environmental differences in AARGs to identify high-risk areas, and forwardly proposes the STI exposure dose of AARGs to guide risk assessment.