Meyer Corina, Bär Mara L, Hollender Juliane
Eawag: Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse 133, 8600, Duebendorf, Switzerland; Institute of Biogeochemistry and Pollutant Dynamics, Universitaetstrasse 16, 8092, Zurich, Switzerland.
Eawag: Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse 133, 8600, Duebendorf, Switzerland.
Environ Int. 2025 Sep;203:109709. doi: 10.1016/j.envint.2025.109709. Epub 2025 Aug 20.
Synthetic antioxidants (SAOs) are widely used additives in industrial and consumer products, yet their human exposure and fate throughout wastewater treatment remain poorly understood. This study investigates the occurrence of SAOs and their human metabolites in wastewater influent as well as their abatement in three wastewater treatment plants (WWTPs) employing both conventional and advanced treatment technologies. In vitro human liver S9 assays were performed to generate a SAO metabolite MS2 library containing over 2500 potential metabolites, which was matched against wastewater influent data. This approach revealed fenozan, which was detected in the influent of all three WWTPs, as a potential biomarker for five of the seven analyzed 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate antioxidants. Detection of the glucuronide conjugate in urinary samples together with the tested high hydrolytic stability of the parent SAOs further qualify fenozan as a potential biomarker. Biological wastewater treatment led to high abatement for most SAOs with a mean value of approximately 70% across all 18 detected SAOs in the three investigated WWTPs. Subsequent ozonation led to further abatement (≥68%), particularly for the amine antioxidants. This can be attributed to their aniline-type structures with low pK values, which render their second-order rate constants with ozone pH-independent at pH values typical for wastewater. For phenolic antioxidants in contrast, the second-order rate constants with ozone are pH-dependent, leading to varying abatements. These results emphasize the important role of wastewater treatment in mitigating SAO pollution. Overall, this study demonstrates the value of wastewater monitoring as a unified approach to assess both human and environmental exposure to SAOs.
合成抗氧化剂（SAOs）是工业和消费品中广泛使用的添加剂，然而人们对其在整个废水处理过程中的人体暴露情况和归宿仍知之甚少。本研究调查了合成抗氧化剂及其人体代谢产物在废水进水口的出现情况，以及它们在采用传统和先进处理技术的三个污水处理厂（WWTPs）中的去除情况。进行了体外人肝S9试验，以生成一个包含2500多种潜在代谢产物的合成抗氧化剂代谢产物MS2库，并将其与废水进水数据进行匹配。这种方法揭示了在所有三个污水处理厂的进水口中都检测到的非诺赞，它是七种分析的3-(3,5-二叔丁基-4-羟基苯基)丙酸酯抗氧化剂中五种的潜在生物标志物。尿液样本中葡萄糖醛酸缀合物的检测以及母体合成抗氧化剂经测试的高水解稳定性进一步证明非诺赞是一种潜在的生物标志物。生物废水处理对大多数合成抗氧化剂有很高的去除率，在三个调查的污水处理厂中，所有18种检测到的合成抗氧化剂的平均去除率约为70%。随后的臭氧化处理导致进一步的去除（≥68%），特别是对于胺类抗氧化剂。这可归因于它们具有低pK值的苯胺型结构，这使得它们与臭氧的二级反应速率常数在废水典型的pH值下与pH无关。相比之下，对于酚类抗氧化剂，与臭氧的二级反应速率常数取决于pH值，导致去除率各不相同。这些结果强调了废水处理在减轻合成抗氧化剂污染方面的重要作用。总体而言，本研究证明了废水监测作为一种统一方法来评估人类和环境对合成抗氧化剂暴露的价值。
