Key Laboratory for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Science, East China Normal University , Shanghai 200241, China.
Joint Research Institute for New Energy and the Environment, East China Normal University and Colorado State University , Shanghai 200062, China.
Environ Sci Technol. 2017 Nov 7;51(21):12859-12867. doi: 10.1021/acs.est.7b03797. Epub 2017 Oct 19.
Landfills receive about 350 million tons of municipal solid wastes (MSWs) per year globally, including antibiotics and other coselecting agents that impact antimicrobial resistance (AMR). However, little is known about AMR in landfills, especially as a function of landfill ages. Here we quantified antibiotics, heavy metals, and AMR genes (ARGs) in refuse and leachates from landfills of different age (<3, 10, and >20 years). Antibiotics levels were consistently lower in refuse and leachates from older landfills, whereas ARG levels in leachates significantly increased with landfill age (One-way ANOVA, F = 10.8, P < 0.01). Heavy metals whose contents increased as landfills age (one-way ANOVA, F = 12.3, P < 0.01) were significantly correlated with elevated levels of ARGs (Mantel test, R = 0.66, P < 0.01) in leachates, which implies greater AMR exposure risks around older landfills. To further explain ARGs distributional mechanisms with age, microbial communities, mobile genetic elements (MGEs) and environmental factors were contrasted between refuse and leachate samples. Microbial communities in the refuse were closely correlated with ARG contents (Procrustes test; M = 0.37, R = 0.86, P < 0.001), whereas ARG in leachates were more associated with MGEs.
全球范围内，垃圾填埋场每年接收约 3.5 亿吨城市固体废物（MSW），其中包括抗生素和其他共选择剂，这些物质会影响抗微生物药物耐药性（AMR）。然而，对于垃圾填埋场中的 AMR 情况，人们知之甚少，尤其是作为填埋场年龄的函数。在这里，我们定量测定了来自不同年龄（<3 年、10 年和>20 年）垃圾填埋场的垃圾和渗滤液中的抗生素、重金属和抗微生物药物耐药性基因（ARGs）。与较老的垃圾填埋场中的垃圾和渗滤液相比，抗生素的水平在垃圾中一直较低，而渗滤液中的 ARG 水平随着填埋场年龄的增加而显著增加（单向方差分析，F = 10.8，P < 0.01）。随着垃圾填埋场年龄的增加而增加的重金属（单向方差分析，F = 12.3，P < 0.01）与渗滤液中升高的 ARG 水平（Mantel 检验，R = 0.66，P < 0.01）呈显著相关，这意味着在较老的垃圾填埋场周围存在更大的 AMR 暴露风险。为了进一步解释随着年龄的增长 ARGs 的分布机制，我们对比了垃圾和渗滤液样本中的微生物群落、移动遗传元件（MGEs）和环境因素。垃圾中的微生物群落与 ARG 含量密切相关（Procrustes 检验；M = 0.37，R = 0.86，P < 0.001），而渗滤液中的 ARG 则与 MGEs 更相关。
