摘要

垃圾渗滤液中人类病原体和抗生素抗性基因（ARGs）的高丰度已成为危害人类健康的新兴威胁。因此，应用硫酸盐和煅烧改性的蛋壳作为绿色农业生物资源来测试从渗滤液中去除致病菌和ARGs的可行性。通过蛋壳与硫酸盐和煅烧相结合处理，人工污染垃圾渗滤液对大肠杆菌和庆大霉素抗性基因（gmrA）的去除率最高。在24小时内，大肠杆菌的16S和gmrA基因拷贝分别从1.78E8±8.7E6和4.12E8±5.9E6拷贝mL-1显着下降至1.32E7±2.6E6和2.69E7±7.2E6拷贝mL-1动态吸附平衡过程（p <0.05）。此外，根据Langmuir动力学模型，可以在中性pH7.5下获得最大吸附量（1.56×109CFU大肠杆菌/克改性蛋壳）。然后筛选出最佳吸附蛋壳进一步应用于中国东部南京的三个典型垃圾填埋场渗滤液。致病菌和ARGs（tet，sul，erm，qnr和ampC）的种类和丰度显着降低，表明其净化垃圾渗滤液的效率很高。这项研究表明硫酸煅烧的蛋壳可以成为一种环境友好且高效的生物吸附剂，用于降低垃圾渗滤液中病原体和ARG的传播风险。

High abundance of human pathogen and antibiotic resistance genes (ARGs) in landfill leachate has become an emerging threat against human health. Therefore, sulfate- and calcination-modified eggshells as green agricultural bioresource were applied to test the feasibility of removing pathogenic bacteria and ARGs from leachate. The highest removal of Escherichia coli (E. coil) and gentamycin resistant gene (gmrA) from artificial contaminated landfill leachate was achieved by the application of eggshell with combined treatment of sulfate and calcination. The 16S and gmrA gene copies of E. coil declined significantly from 1.78E8 ± 8.7E6 and 4.12E8 ± 5.9E6 copies mL−1 to 1.32E7 ± 2.6E6 and 2.69E7 ± 7.2E6 copies mL−1, respectively, within 24 h dynamic adsorption equilibrium process (p < 0.05). Moreover, according to the Langmuir kinetic model, the greatest adsorption amount (1.56 × 109 CFU E. coil per gram of modified eggshells) could be obtained at neutral pH of 7.5. The optimal adsorption eggshells were then screened to the further application in three typical landfill leachates in Nanjing, eastern China. Significant decrease in species and abundance of pathogenic bacteria and ARGs (tet, sul, erm, qnr, and ampC) indicated its great efficiency to purify landfill leachates. This study demonstrated that sulfate-calcined eggshells can be an environmentally-friendly and highly efficient bioadsorbent to the management of reducing dissemination risk of pathogen and ARGs in landfill leachate.

https://www.sciencedirect.com/science/article/pii/S0956053X17301150