en عمومى General مقاله اصیل Original Article <div style="text-align: justify;">Introduction: Antibiotics are among the most persistent pollutants in aquatic environments, posing ecological and health risks. This study evaluated the degradation of tetracycline in aqueous solutions using ozone-based advanced oxidation processes (AOPs).<br> Methods: Ozone (O3), O3/UV, and O3/H2O2 systems were compared under varying operational conditions in a batch reactor. The effects of pH, oxidant dosage, and reaction time on degradation efficiency were assessed. Biotoxicity and biodegradability changes were monitored using E. coli inhibition and the BOD5/COD ratio.<br> Results: The O3/H2O2 system achieved the highest degradation efficiency (99.2%) and improved wastewater biodegradability (BOD5/COD = 0.67). In contrast, single ozonation achieved 69.2% removal. The combination of ozone and hydrogen peroxide significantly reduced effluent toxicity, lowering E. coli inhibition by 6.34%.<br> Conclusion: The synergistic O3/H2O2 process demonstrated superior performance in tetracycline removal and detoxification, highlighting its potential as a sustainable and effective pre-treatment for pharmaceutical wastewater.</div> Ozone, Tetracycline, Hydrogen peroxide, Oxidation-reduction 1 10 http://ehemj.com/browse.php?a_code=A-10-1-444&slc_lang=en&sid=1 Seyed Javad Jafari j1986.javad@gmail.com 100319475328460021928 100319475328460021928 No Department of Environmental Health Engineering, School of Public Health, Urmia University of Medical Sciences, Urmia, Iran Daryoush Valipour valipoordaryoush@gmail.com 100319475328460021929 0009-0003-0511-746X No Department of Environmental Health Engineering, School of Public Health, Urmia University of Medical Sciences, Urmia, Iran Heydar Ahadi ali.ahadi1280@yahoo.com 100319475328460021930 0009-0002-1935-2690 Yes Correspondence to: Department of Environmental Health Engineering, School of Public Health, Urmia University of Medical Sciences, Urmia, Iran