摘要

    由于人体通过吸入接触，已广泛研究了通过空气介质（例如颗粒物）传播抗生素抗性基因（ARG）的方法。然而，未知来自堆肥厂的大气环境的颗粒物是否会影响堆肥过程中的ARG丰度。在这里，我们研究了堆肥厂的大气环境对污泥堆肥过程中使用半透膜覆盖的嗜热堆肥（smTC）和常规嗜热堆肥（cTC）的ARG丰度的影响。经过smTC处理后，ARG和移动遗传元件（MGE）的总丰度分别比初始阶段降低了42.1％和38.1％，但在cTC之后分别增加了4.5倍和1.6倍。该结果表明，smTC在降低ARG和MGE方面比cTC更有效，这主要是由于堆肥厂大气环境中细菌污染的显着减少，从而加速了ARG和MGE的复兴。此外，培养实验表明，在smTC成熟阶段，抗生素抗性细菌的丰度和多样性也显着低于（p <0.05）cTC处理。因此，用半透膜覆盖堆肥可以降低ARGs扩散的风险。

    Transmission of antibiotic resistance genes (ARGs) via air media, such as particulate matter, has been intensively investigated due to human exposure through inhalation. However, whether particulate matter originating from the atmospheric environment of composting plants can impact ARG abundance during composting is unknown. Here, we investigated the effects of the atmospheric environment of composting plants on ARG abundance during sewage sludge composting using semi-permeable membrane-covered thermophilic composting (smTC) and conventional thermophilic composting (cTC). After smTC treatment, the total abundances of ARGs and mobile genetic elements (MGEs) decreased by 42.1 % and 38.1 % compared with those of the initial phase, respectively, but they increased by 4.5- and 1.6-fold after cTC, respectively. This result suggested that smTC was more efficient at decreasing ARGs and MGEs than cTC, mainly due to a significant reduction in bacterial contamination from the atmospheric environment of composting plants that accelerated the resurgence of ARGs and MGEs. Furthermore, culture experiments demonstrated that the abundance and diversity of antibiotic-resistant bacteria during the mature phase of smTC were also significantly (P <  0.05) lower than those in the cTC treatment. Thus, covering composting with a semi-permeable membrane could decrease the risk of ARGs spreading.

    https://www.sciencedirect.com/science/article/abs/pii/S0304389420307275