Gamma radiation and UV radiation-based advanced oxidation processes for the toxicity and mutagenicity reduction of reactive orange 122 dye aqueous solution.

This study focuses on the determination of cytotoxicity and mutagenicity of Reactive Orange 122 dye (RO122). The ultraviolet (UV) and gamma (γ) radiations along with hydrogen peroxide (H2O2) were employed as an advanced oxidation process (AOPs). The 50 mg/L of dye solution were treated with UV radiation for 30-150 min and γ-ray absorbed doses (1-5 kGy) alone and in conjunction with H2O2. The untreated dye solutions have shown cytotoxicity and mutagenicity, which were decreased after treatment. The Allium cepa test showed 39.35, 46.16 and 52.44 (%) increase in root length (RL), root count (RC) and mitotic index (MI) for UV/H2O2-treated RO122 samples, whereas RL, RC and MI were increased up to 63.52, 70.32 and 89.98 (%), respectively for γ/H2O2 treatment. The brine shrimp assay has shown a reduction in mortality up to 82.95 and 91.30 (%) after UV/H2O2 and γ/H2O2 treatment, respectively. The hemolytic assay revealed a 32.5 and 62.4 (%) hemolysis for UV/H2O2 and γ/H2O2, respectively. The Ames test was performed using S. typhimurium strains to determine the mutagenicity of treated and untreated dye. The results indicated that cytotoxicity and mutagenicity of dye solutions were reduced following treatment with the selected AOPs. Further investigation into the scalability, energy efficiency and real wastewater applicability of these AOPs is recommended to facilitate their practical implementation in sustainable water treatment systems.