Liu Ning, Xu Like, Han Lujia, Huang Guangqun, Ciric Lena
Engineering Laboratory for AgroBiomass Recycling & Valorizing, College of Engineering, China Agricultural University, Beijing 100083, China.
Healthy Infrastructure Research Group, Department of Civil, Environmental & Geomatic Engineering, University College London, Gower Street, WC1E 6BT London, UK.
J Hazard Mater. 2021 Jan 5;401:123391. doi: 10.1016/j.jhazmat.2020.123391. Epub 2020 Jul 4.
This study evaluated the microbial safety and antibiotic resistance risks of a sustainable ecological farm under large-scale open-air composting (OC) and green composting toilet systems (CT). Samples of livestock manure, compost, soil, vegetables, and rainwater were analysed to determine the best treatment of wastes and risk assessment of land application. Results showed that pathogenic bacteria (PB) in livestock manure was significantly greater than that in the surrounding topsoil, while the distribution of bacteria resistant to amoxicillin (AMX), tetracycline (TC), and amoxicillin-tetracycline (AMX- TC) was the opposite through long-term resistance selection pressure. E. coli and Enterococcus were the dominant pathogens in feces and surrounding soil, respectively, and AMX-resistant bacteria dominated soil, compost, and vegetable samples. Overall, while OC may significantly increase antibiotic resistance and effectively remove fecal PB, CT offers faster consumption with greater antibiotic resistant bacteria (ARB) removal but more PB. Moreover, PB and ARB were concentrated in mature compost, soil in planting areas, vegetables, and rainwater. In farm soil and vegetables, AMX-resistant and AMX-TC-resistant bacterial communities displayed similar composition. These findings may explain the main pathways of PB transmission, migration and accumulation of ARB in farms, and the potential risks to human health through the food chain.
本研究评估了大规模露天堆肥（OC）和绿色堆肥厕所系统（CT）下可持续生态农场的微生物安全性和抗生素抗性风险。对牲畜粪便、堆肥、土壤、蔬菜和雨水样本进行分析，以确定废物的最佳处理方式和土地施用的风险评估。结果表明，牲畜粪便中的病原菌（PB）显著高于周围表土，而通过长期抗性选择压力，对阿莫西林（AMX）、四环素（TC）和阿莫西林 - 四环素（AMX - TC）耐药的细菌分布情况则相反。大肠杆菌和肠球菌分别是粪便和周围土壤中的主要病原菌，且耐AMX细菌在土壤、堆肥和蔬菜样本中占主导。总体而言，虽然OC可能会显著增加抗生素抗性并有效去除粪便中的PB，但CT消耗更快，去除的抗生素抗性细菌（ARB）更多，但PB更多。此外，PB和ARB集中在成熟堆肥、种植区土壤、蔬菜和雨水中。在农场土壤和蔬菜中，耐AMX和耐AMX - TC细菌群落组成相似。这些发现可能解释了农场中PB传播、ARB迁移和积累的主要途径，以及通过食物链对人类健康的潜在风险。
