摘要

       残留的废水固体是抗生素抗性基因 (ARG) 的重要储存库。虽然处理技术可以降低残留废水固体中的 ARG 水平，但这些技术在随后的土地应用过程中对土壤中 ARG 的影响尚不清楚。在这项研究中，我们研究了多种处理技术（空气干燥、好氧消化、中温厌氧消化、高温厌氧消化、巴氏杀菌和碱稳定）对废水固体修正土壤微观世界中 ARG 和 1 类整合子的命运的影响。 6个ARGs [erm(B), qnrA, sul1, tet(A), tet(W), and tet(X)]，1类整合子的整合酶基因(intI1)，16S rRNA基因使用定量聚合酶链进行定量反应。所有微观世界中 ARGs 和 intI1 的数量都减少了，但嗜热厌氧消化、碱稳定和巴氏杀菌导致 ARGs 和 intI1 最广泛的腐烂，通常达到与未施加废水固体的对照微观世界相似的水平.相比之下，使用其他治疗技术的 ARGs 和 intI1 下降的速度大致相似，通常变化不到 2 倍。这些结果表明，废水固体处理技术可用于降低 ARG 和 intI1 在随后应用于土壤期间的持久性。

       Residual wastewater solids are a significant reservoir of antibiotic resistance genes (ARGs). While treatment technologies can reduce ARG levels in residual wastewater solids, the effects of these technologies on ARGs in soil during subsequent land-application are unknown. In this study we investigated the use of numerous treatment technologies (air drying, aerobic digestion, mesophilic anaerobic digestion, thermophilic anaerobic digestion, pasteurization, and alkaline stabilization) on the fate of ARGs and class 1 integrons in wastewater solids-amended soil microcosms. Six ARGs [erm(B), qnrA, sul1, tet(A), tet(W), and tet(X)], the integrase gene of class 1 integrons (intI1), and 16S rRNA genes were quantified using quantitative polymerase chain reaction. The quantities of ARGs and intI1 decreased in all microcosms, but thermophilic anaerobic digestion, alkaline stabilization, and pasteurization led to the most extensive decay of ARGs and intI1, often to levels similar to that of the control microcosms to which no wastewater solids had been applied. In contrast, the rates by which ARGs and intI1 declined using the other treatment technologies were generally similar, typically varying by less than 2 fold. These results demonstrate that wastewater solids treatment technologies can be used to decrease the persistence of ARGs and intI1 during their subsequent application to soil.

https://pubs.acs.org/doi/abs/10.1021/acs.est.7b04760