摘要

       在这项研究中，使用实验室规模的反应器系统在好氧堆肥过程中将 100mg/kg 阿莫西林 (AMX) 添加到猪粪中，以更好地了解 AMX 的降解及其潜在风险。然后使用固相萃取结合高效液相色谱-串联质谱法对 AMX 及其主要降解产物 (DP) 进行定性和定量分析。此外，还进行了水解测试以监测在各种受控条件下由 AMX 降解产生的 DP。结果表明，AMX 在堆肥中不稳定并迅速降解为 AMX 青霉酸、AMX 青霉酸和 AMX 二酮哌嗪，最终全部降解，留下结构简单且稳定的终产物，3-(4-羟基苯基)吡嗪-2-醇，与堆肥过程中早期产生的 DP 相比，它似乎是非过敏性的且毒性更小。此外，与酸性或中性条件或超纯水相比，AMX 在碱性条件下更不稳定，更容易产生多个 DP，而 pH 对 AMX 降解的影响大于二价金属离子（Cu2+ 和 Zn2+）。本研究为更好地实现AMX残留处理和评估中国堆肥中大量产生的AMX DPs的安全性提供了技术和方法支持。

       In this study, 100 mg/kg of amoxicillin (AMX) was added to pig manure during aerobic composting using a laboratory-scale reactor system, for better understanding the degradation of AMX and its potential risks. Qualitative and quantitative analysis of AMX and its main degradation products (DPs) were then conducted using solid phase extraction combined with high performance liquid chromatography-tandem mass spectrometry. Additionally, hydrolysis testing was performed to monitor DPs produced from AMX degradation under various controlled conditions. The results showed that AMX was unstable in compost and rapidly degraded into AMX penicilloic acid, AMX penilloic acid and AMX diketopiperazine, which all eventually degraded, leaving a structurally simple and stable end product, 3-(4-hydroxyphenyl) pyrazin-2-ol, which appeared to be nonallergenic and less toxic than DPs generated earlier in the composting process. Besides, AMX was more unstable and more apt to generate multiple DPs in alkaline conditions than in acidic or neutral conditions or in ultrapure water, while pH exerted a larger effect on AMX degradation than did divalent metal ions (Cu2+ and Zn2+). This study provides technical and methodological support to better achieve AMX residual treatment and to evaluate the safety of AMX DPs produced in huge quantities in compost in China.

https://www.sciencedirect.com/science/article/abs/pii/S0304389417308725