## 5 Decontamination of Chemical Pollutants
In another study, phenol degradation was studied by plasma treatment. The phenol degradation results achieved by underwater plasma treatment were widely discussed in a recent review [37] mainly focused on their elimination strategy. NTAPP exposure degrades phenol liquids efficiently, where the resulting reaction products can be identified by high-performance liquid chromatography (HPLC). The mechanism of phenol oxidation by the presence of OH radicals and O\({}_{3}\), as well as more detailed nitration and nitridation mechanisms, has been explained previously [105]. Numerous studies have indicated that compared to traditional AOPs, NTAPP treatment has the potential to degrade pharmaceuticals with high energy efficiency and low energy requirements compared to O\({}_{3}\) treatment [106; 107; 108]. This property makes NTAPP application a practical substitute for conventional wastewater management processes. The primary benefits of using NTAPP to destroy organic composites include the minimal environmental harm caused by this approach. NTAPP-generated reactive species, such as OH radicals, H\({}_{2}\)O\({}_{2}\), and O\({}_{3}\), not only react superficially with pollutants, but also diffuse in the bulk phase [109; 110; 111]. Dimethylphal (DMP) is widely used as a plasticizer and acts as a water pollutant. [PERSON] et al. [112] used a micro plasma-based AOP process wherein liquid-gas discharge was used for DMP removal. Moreover, the use of this enhanced performance method was accomplished by comparison with the other existing methods, including electrocoagulation and ozonation. The authors observed that plasma-generated O\({}_{3}\) and OH radicals were the key reactive components inside plasma-degraded DMP liquid, which hit numerous DMP functional groups for degradation. The effectiveness of DMP degradation is highly reliant on the treatment time and discharge power when used for water treatment. This report shows that air microplasma exposure could be used as a possible tool for wastewater purification [112]. Several pharmaceuticals have been observed in above-ground water [113] and groundwater [114], including streams [115]. Figure 8 depicts the application of NTAPP for pharmaceutical component degradation in water. Antibiotics, as one class of pharmaceuticals, are widely studied due to the development of bacteria with antibiotic resistance [116]. Their oxidative elimination by plasma is quite beneficial; nonetheless, mineralization has been confirmed to be moderately slow [107; 117; 118]. Based on the determined oxidation intermediates, researchers have suggested that the main degradation mechanism relies on OH radical attacks, subsequent hydroxylation, and the damaging of molecular bonds, which leads to mineralization [117; 118]. Reports on the application of NTAPP to remove antibiotics such as atenol [119], verapamil [120], and enalapril [121] have been pub lished. [PERSON] et al. [120] proposed that DBD reactors attack OH radicals and O\({}_{3}\) on the amino group and aromatic rings for verapamil oxidation. Another compound called carbamazepine, the highest determined environment pharmaceutical, is hazardous to aquatic species and has endocrine-disrupting activity [122]. To address this issue, [PERSON] et al. [123] developed a low-power ex situ plasma treatment method, which exhibited high efficiency on carbamazepine compared to DBD plasma. This effect was recognized by the generation of N oxides, and the consequent reactions with OH radicals or/and O\({}_{3}\), which decreased the oxidizer levels to prevent chain reactions instigated by O\({}_{3}\)[123]. Similarly, Ibuprofen degradation in water was achieved in another study by pulsed corona discharge of NTAPP over liquid, produced in O\({}_{2}\). Interestingly, complete Ibuprofen removal was achieved within 20 min of NTAPP exposure, and the mineralization level increased to 76% after 1 h. Another group proposed a plasma-ozonation combined system, where suitable mass transmission of the NTAPP-produced O\({}_{3}\) to the treated liquid was confirmed [124].