Simple anaerobic digestion is insufficient to completely remove residual parent antibiotics and antibiotic resistance genes (ARGs) from animal manure. ARG prevalence in swine biogas slurry-irrigated soils threatens human health. However, comprehensive analysis of antibiotic residues, high-resolution resistance gene profiles, and pathogenic microbiomes in biogas slurry-irrigated soils is very limited. Here, we comprehensively determined the antibiotics, resistome, and potential pathogens distribution in these soils, using high-performance liquid chromatography-tandem mass spectrometry, high-throughput quantitative PCR, and 16S rRNA gene sequencing. The results revealed a significant enrichment of tetracyclines and fluoroquinolones antibiotics and ARGs in soils with prolonged biogas slurry irrigation, with a total of 12 antibiotics, 175 unique ARGs, and 9 mobile genetic elements (MGEs) detected. Quantification of veterinary antibiotic residues (especially chlortetracycline) showed significant correlations with multiple ARGs. The abundance of ARGs and MGEs was highest in the biogas slurry-irrigated soils, denoting a tight link between the application of biogas slurry and the spread of antibiotic resistance. The presence of 50 potential pathogenic bacterial genera, including 13 with multidrug resistance, was identified. Variation partitioning, combined with hierarchical partitioning analysis, indicated that Firmicutes, MGEs, and tetracyclines were the key drivers shaping the ARG profiles in biogas slurry-irrigated soils. The findings offer insights into the mechanisms of antibiotic residue and ARGs spread from the agricultural practice of biogas slurry irrigation, underscoring the necessity of sustainable soil management to mitigate the spread of antibiotic resistance.

中文翻译：

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猪沼液灌溉土壤的环境风险：抗生素残留、抗药性和细菌病原体的综合分析


简单的厌氧消化不足以完全去除动物粪便中残留的母体抗生素和抗生素抗性基因（ARG）。猪沼液灌溉土壤中 ARG 的流行威胁着人类健康。然而，对沼液灌溉土壤中抗生素残留、高分辨率抗性基因谱和病原微生物组的综合分析非常有限。在这里，我们利用高效液相色谱-串联质谱、高通量定量PCR和16S rRNA基因测序，全面测定了这些土壤中的抗生素、抗药性和潜在病原体的分布。结果显示，长期沼液灌溉的土壤中四环素类和氟喹诺酮类抗生素和 ARG 显着富集，共检测到 12 种抗生素、175 种独特 ARG 和 9 种移动遗传元件 (MGE)。兽用抗生素残留（尤其是金霉素）的定量显示与多种 ARG 显着相关。沼液灌溉土壤中 ARGs 和 MGEs 的丰度最高，表明沼液的应用与抗生素耐药性的传播之间存在密切联系。鉴定出 50 种潜在致病菌属，其中 13 种具有多重耐药性。变异划分与层次划分分析相结合表明，厚壁菌门、MGE 和四环素是影响沼液灌溉土壤中 ARG 分布的关键驱动因素。研究结果深入了解了沼液灌溉农业实践中抗生素残留和抗生素耐药性传播的机制，强调了可持续土壤管理以减轻抗生素耐药性传播的必要性。