School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China.
School of Resources, Environment and Materials, Guangxi University, Nanning, 530004, China; Guangxi Key Laboratory of Clean Pulp & Papermaking and Pollution Control, Guangxi University, Nanning, 530004, China.
Chemosphere. 2020 Jun;248:126017. doi: 10.1016/j.chemosphere.2020.126017. Epub 2020 Jan 27.
Every year, the harvesting of Eucalyptus generates a large amount of abandoned Eucalyptus leaves (ELs), which may release dissolved organic matter (DOM) when immersed in water. If these substances are carried by surface runoff directly to the source of drinking water, some components in the DOM tend to form disinfection byproducts (DBPs) within the water-supply system, posing risk to human health. In this study, the characteristics of DOM released from leaves of Eucalyptus urophylla were studied and the potential of DBPs formation of the EL-released DOM during the chlorination process was investigated. The results showed that the EL-released DOM was mainly composed of small molecules and hydrophobic substances. Of the total EL-released DOM, the proportion with molecular weight less than 10 kDa accounted for over 80% and the hydrophobic substances took up over 62%. The DOM showed strong absorbance at UV and the fluorescence response corresponding to humic acid-like (HA-like) fractions, soluble microbial byproduct-like, aromatic protein and fulvic acid-like (FA-like) material, which have been considered to be related to the potential precursors of chlorinated DBPs. Non-targeted screening demonstrated the presence of phenolics, carbohydrates, and amino acids. The analysis of products generated in chlorination process revealed the formation of trichloromethane (TCM) and the total organic halogen (TOX). The present study fully confirms that the DOM released from Eucalyptus urophylla leaves has great potential for the generation of chlorinated DBPs.
每年，桉树的收割都会产生大量废弃的桉树叶子（ELs），当这些叶子浸泡在水中时，可能会释放出溶解的有机物（DOM）。如果这些物质通过地表径流直接进入饮用水源，DOM 中的一些成分在供水系统中容易形成消毒副产物（DBPs），对人体健康构成威胁。本研究对尾巨桉树叶释放的 DOM 特征进行了研究，并考察了 EL 释放 DOM 在氯化过程中形成 DBPs 的潜力。结果表明，EL 释放的 DOM 主要由小分子和疏水性物质组成。在总 EL 释放的 DOM 中，分子量小于 10 kDa 的比例超过 80%，疏水性物质占比超过 62%。DOM 在紫外光下具有较强的吸光度，荧光响应对应于腐殖酸类（HA 类）、可溶微生物副产物类、芳香族蛋白类和富里酸类（FA 类）物质，这些物质被认为与氯化 DBPs 的潜在前体有关。非靶向筛选表明存在酚类、碳水化合物和氨基酸。氯化过程中产物的分析表明三氯甲烷（TCM）和总有机卤素（TOX）的生成。本研究充分证实了尾巨桉树叶释放的 DOM 具有生成氯化 DBPs 的巨大潜力。
