## 4 Mitigation Methods for Disinfecting AMR Pathogens and Genes in Wastewater Treatment
### Photocatalysis
Like TiO\({}_{2}\) and their composites, Ag/AgBr/g-C\({}_{3}\)N, nano composites had also been employed in degrading tetracycline-resistant genes from waste-water under visible light irradiation-based photocatalysis, and the ARG removal efficiencies of the nanocomposites for _tetA_, _tetM_ and _tetQ_ were found to be 49%, 86% and 69%, respectively [96]. [PERSON] et al. [98] extended the study for the determination of the performance of TiO\({}_{2}\)-based photocatalysis along with solar light-driven photolysis for the removal of ARGs from wastewater. The study revealed the enhanced efficiency of photocatalysis (83.8%) compared to solar-driven photolysis (80%) for the removal of ARGs such as from wastewater. More recently [PERSON] et al. [97] combined a photocatalytic treatment system with a constructed wetland for WWT and assessed its efficiency in removing ARGs such as _sul1_, _sul2_ (sulfonamide resistance) and _tetQ_ (tetracycline resistance) from urban MWW. The results showed that the combined treatment with photocatalysis and constructed wetlands significantly reduced both intracellular (1.27-1.72 log values) ARGs and extracellular ARGs (0.23-0.65 log values) from wastewater samples. Fenton oxidation processes are highly efficient and relatively cheap processes that have emerged as promising methods for the elimination of ARGs from wastewaters. In the Fenton oxidation process, a OH free radicals (OH\(\bullet\)) or a singlet oxygen (\({}^{1}\)O\({}_{2}\)) produced from the reaction between H\({}_{2}\)O\({}_{2}\) and Fe\({}^{2+}\)/Fe\({}^{3+}\) (constituents of Fenton reagents) lyse cells in an acidic medium [106; 110]. Due to its enhanced efficiency, operational ease and low inherent toxicity, Fenton oxidation has been employed as an advanced method for wastewater treatment [111]. [PERSON] et al. [121] evaluated the performance of Fenton oxidation process in WWT plants and found that it efficiently reduced the concentration of ARGs such as _sull1_, _tetX_ and _tetG_ (e.g., 2.58 to 3.79 logs of ARGs) in wastewater effluents after treatment with UV/H\({}_{2}\)O\({}_{2}\). In addition, solar-driven Fenton oxidation linked with membrane bioreactors were tested for the removal of ARGs such as _sull_, _ermB_ and _ampC_ from wastewater samples [112], which were found to reduce the total DNA concentration in the wastewater sample by 97%. Similarly, [PERSON] et al. [87] validated the performance of solar-driven photo-Fenton process for the removal of the carbapenem-resistant gene, i.e., _bla-KPC_ from HWW. It was observed that total degradation _bla-KPC_ was achieved through this process in 5 h. The solar photo-Fenton process (combined with granular activated carbon treatment) was also extended to assess its potential for eliminating ARGs from urban wastewater effluents. The method effectively degraded ARGs such as _blaOXA_, _blaCTX-M_, (beta-lactam resistance) _qnrS_, (quinoline resistance) _sull_ (sulfonamide resistance) and _tetM_ (tetracycline resistance) in the wastewater samples [106]. Yet another study by [PERSON] et al. [107] studied the enhanced removal of the antibiotic resistant _E. coli_ and ARGs such as _tetA_ and _blaT_ by a Photo- Fenton process under visible LED light and neutral pH. Similarly [PERSON] et al. [105] designed a modified photo-Fenton system with ethylenediamine-N,N -di-succinic acid (EDDS) and investigated its performance for the degradation of ARGs from wastewater effluents. This process was found to degrade both intercellular (iARGs) and extracellular ARGs (eARGs), including _ietA_ (3.79 log value), _iblatTEM_ (2.19 log reduction), _etetA_ and _elbTA_ (-6 log reduction each).