Airborne PM₁₀ is an important vector carrying antibiotic resistance genes (ARGs) emitted from environmental hotspots. However, whether these inhalable ARGs could be effectively transmitted to human beings, as well as the in vivo exposure consequences still remains unknown. Here, we studied these inhalable ARGs in Asia’s largest municipal waste treatment center (n = 84) and analyzed their relationships with the antibiotic resistomes niched in the upper-airway of on-site workers (n = 30). During the year-long study, air and airway resistomes exhibited setting-featured resistances (P < 0.001). However, compared to other environmental settings (landfill waste, leachate, waste-digestate), airborne PM₁₀ characterized with a high transmission network connectivity was mostly associated with the on-site workers’ airway concerning the resistome structure. Notably, the non-randomly distributed ‘air-airway’ ARGs (NST = 23%) were more likely to be hosted by microbial assembly-dominant bacteria. These taxa were substantially different between the air and airway samples, and thereby forged the setting-featured resistances like tetracycline resistances in air, while macrolides-lincosamides-streptogramines and aminoglycoside ones in airway. Meantime, rather than plasmids, the bacteriophages contributed to cross-phylum transfer of ARGs, facilitating the exchange of between the air- and airway-assembly dominant taxa. Furthermore, several phylogenetically closely related bacteria (e.g. Corynebacterium, Pseudomonas, Streptococcus sp.) were identified in both air-PM₁₀ and airway-swabs regardless of seasons. This putative ARG hosts transmission suggest a direct and long-lasting inhalation risks.
 

抗生素耐药,宏基因组,吸入暴露,病原微生物