Occurrence and Distribution of Urban Dust-Associated Bacterial Antibiotic Resistance in Northern China

The occurrence and distribution of 20 subtypes of antibiotic resistance genes (ARGs), conferring sulfonamide, tetracycline, macrolide, β-lactam, aminoglycoside, or quinolone antibiotic resistance, were investigated in urban dust samples collected from the surfaces of three megacities (Beijing, Tianjin, and Shijiazhuang) of northern China. Real-time polymerase chain reaction indicated that the abundance of ARGs and 16S rRNA genes was significantly higher in the summer than in the winter. A total of 80 antibiotic-resistant bacteria were isolated and identified, and 12 of those species were identified as opportunistic pathogens. An isolated pathogen <i>Acinetobacter</i> sp. was proven to be able to transfer antibiotic resistance, which highlights the potential risk that an urban dust-associated ARG poses to public health. Deep 16S rRNA sequencing indicated high heterogeneity of bacterial communities among cities in the summer, but great homogeneity in the winter. In the summer, <i>Enterococcus</i>, <i>Massilia</i>, and <i>Anthrobacter</i> were the most prevalent genera in Tianjin, Beijing, and Shijiazhuang, respectively. However, the most prevalent bacterial genera were <i>Bacillus</i> and <i>Lactococcus</i> in the winter. This is the first study of the occurrence and distribution of the urban dust-associated bacterial community and its associated bacterial antibiotic resistance in northern China. This study highlights the risk of dust-associated antibiotic resistance to public health