State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 211135, China; University of Chinese Academy of Sciences, Beijing 100049, China; Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing 210095, China.
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 211135, China; Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing 210095, China; College of Environment and Ecology, Jiangsu Open University, Nanjing 210017, China.
J Hazard Mater. 2024 Dec 5;480:135790. doi: 10.1016/j.jhazmat.2024.135790. Epub 2024 Sep 10.
Agricultural soils are important source and sink of antibiotic resistance genes (ARGs). However, little is known about the fate of ARGs in dryland soils, while its human exposure risks were seriously overlooked. Taking the northern Ningxia Plain as a case, this study explored the occurrence of ARGs and its relationship with mobile genetic elements (MGEs), pathogens, and environmental factors. Furthermore, the concentrations of airborne ARGs by soil wind erosion and the human exposure doses of soil ARGs were evaluated. The results showed the abundances of different regions ranged from 4.0 × 10 to 1.6 × 10 copies/g. Soil ARGs are driven by MGEs, but multiply impacted by soil properties, nutrition, and bacterial community. Vibrio metschnikovii, Acinetobacter schindleri, and Serratia marcescens are potential pathogenic hosts for ARGs. Further exploration revealed the concentration of ARGs loaded in dust by soil wind erosion reached more than 10 copies/m, which were even higher than those found in sewage treatment plants and hospitals. Skin contact is the primary route of ARGs exposure, with a maximum dose of 24071.33 copies/kg/d, which is largely attributed to ARGs loaded in dust. This study bridged the gap on ARGs in dryland soils, and provided reference for human exposure risk assessment of soil ARGs.
农业土壤是抗生素耐药基因（ARGs）的重要源和汇。然而，人们对旱地土壤中 ARGs 的命运知之甚少，而其对人类的暴露风险则严重被忽视。本研究以北方宁夏平原为例，探讨了旱地土壤中 ARGs 的存在及其与可移动遗传元件（MGEs）、病原菌和环境因素的关系。此外，还评估了土壤风蚀携带的气载 ARGs 浓度和土壤 ARGs 对人类的暴露剂量。结果表明，不同地区的 ARGs 丰度范围为 4.0×10 到 1.6×10 拷贝/g。土壤 ARGs 受 MGEs 驱动，但受土壤特性、养分和细菌群落的多重影响。Vibrio metschnikovii、Acinetobacter schindleri 和 Serratia marcescens 是 ARGs 的潜在病原菌宿主。进一步的探索发现，土壤风蚀携带的 ARGs 浓度在尘埃中达到 10 拷贝/m 以上，甚至高于污水处理厂和医院中发现的浓度。皮肤接触是 ARGs 暴露的主要途径，最大暴露剂量为 24071.33 拷贝/kg/d，这主要归因于尘埃中携带的 ARGs。本研究填补了旱地土壤中 ARGs 的空白，为评估土壤 ARGs 对人类的暴露风险提供了参考。
