School of Civil Engineering, Architecture and Urban Design, University of Campinas, P.O. Box 6021, Campinas, SP, 13083-889, Brazil.
Environ Sci Pollut Res Int. 2019 Sep;26(27):27604-27619. doi: 10.1007/s11356-018-2149-1. Epub 2018 May 8.
Advanced oxidation processes (AOPs) have been highly efficient in degrading contaminants of emerging concern (CEC). This study investigated the efficiency of photolysis, peroxidation, photoperoxidation, and ozonation at different pH values to degrade doxycycline (DC) in three aqueous matrices: fountain, tap, and ultrapure water. More than 99.6% of DC degradation resulted from the UV/HO and ozonation processes. Also, to evaluate the toxicity of the original solution and throughout the degradation time, antimicrobial activity tests were conducted using Gram-positive (Bacillus subtilis) and Gram-negative (Escherichia coli) bacteria, and acute toxicity test using the bioluminescent marine bacterium (Vibrio fischeri). Antimicrobial activity reduced as the drug degradation increased in UV/HO and ozonation processes, wherein the first process only 6 min was required to reduce 100% of both bacteria activity. In ozonation, 27.7 mg L of ozone was responsible for reducing 100% of the antimicrobial activity. When applied the photoperoxidation process, an increase in the toxicity occurred as the high levels of degradation were achieved; it means that toxic intermediates were formed. The ozonated solutions did not present toxicity.
高级氧化工艺（AOPs）在降解新兴关注污染物（CEC）方面非常有效。本研究考察了在不同 pH 值下光解、过氧化物、光过氧化物和臭氧化降解水中三种基质（喷泉、自来水和超纯水）中强力霉素（DC）的效率。超过 99.6%的 DC 降解是由 UV/HO 和臭氧化过程引起的。此外，为了评估原始溶液的毒性以及整个降解过程中的毒性，使用革兰氏阳性（枯草芽孢杆菌）和革兰氏阴性（大肠杆菌）细菌进行了抗菌活性测试，并用发光海洋细菌（发光杆菌）进行了急性毒性测试。在 UV/HO 和臭氧化过程中，随着药物降解的增加，抗菌活性降低，其中第一个过程仅需 6 分钟即可完全降低两种细菌的活性。在臭氧化过程中，27.7 mg/L 的臭氧可减少 100%的抗菌活性。当应用光氧化过程时，随着降解水平的提高，毒性增加，这意味着形成了有毒的中间产物。臭氧化溶液没有毒性。
