## 5 Treatment Costs
\\  & & & \(\bullet\) & related to the project. \\  & & & \(\bullet\) & 90\% contaminants removal. \\ \hline UVC & MP, EP, PP, BuP, BeP and & \(\bullet\) & \(\bullet\) & 100\% contaminant removal in 8 h \\  & p-HBA & & \(\bullet\) & Regarding a mixture of parabens and \\  & & & \(\bullet\) & p-HBA \\ \hline UVC/H\({}_{2}\)O\({}_{2}\) & MP, EP, PP, BuP, BeP and & \(\bullet\) & \(\bullet\) & 100\% contaminant removal in 0.5 h \\  & p-HBA & & \(\bullet\) & Regarding a mixture of parabens and \\  & & & \(\bullet\) & p-HBA \\ \hline UV/H\({}_{2}\)O\({}_{2}\) & EP & \(\bullet\) & \(\bullet\) & The total cost is 7.06 \(\xi\)/m\({}^{3}\). \\  & & & \(\bullet\) & Regarding EP degradation with \\  & & & \(\bullet\) & partial concentration of 30 \(\mu\)M, \\  & & & \(\bullet\) & reagent initial concentration of 1 mM, \\  & & & & \\  & & & & \\  & & & & \\  & &  
[PERSON] et al. [27] estimated the degradation costs of a mixture of MP, EP, PP, BeP, and BuP by photocatalytic ozonation with UVA, catalytic ozonation, photolytic ozonation with UVA, and single ozonation, estimating an expense of 2.04 kWh/m\({}^{3}\) (0.26 \(\upxi\)/m\({}^{3}\)), 15 kWh/m\({}^{3}\) (1.91 \(\upxi\)/m\({}^{3}\)), 0.84 kWh/m\({}^{3}\) (0.11 \(\upxi\)/m\({}^{3}\)), and 9.4 kWh/m\({}^{3}\) (1.20 \(\upxi\)/m\({}^{3}\)) for these techniques, respectively. In this study, the use of TiO\({}_{2}\) catalyst seems to decrease the associated treatment costs. [PERSON] et al. [73] used different reagents with UV radiation for EP abatement, achieving a value of 7.06 \(\upxi\)/m\({}^{3}\) (5.93 \(\upxi\)/m\({}^{3}\)), 6.26 \(\upxi\)/m\({}^{3}\) (5.26 \(\upxi\)/m\({}^{3}\)), and 14.62 \(\upxi\)/m\({}^{3}\) (12.28 \(\upxi\)/m\({}^{3}\)) for UV/Hg\({}_{2}\)O\({}_{2}\), UV/PS, and UV/PMS, respectively, and [PERSON] et al. [74] removed MP by UV/PS, estimating costs of 54.2 kWh/m\({}^{3}\) (6.92 \(\upxi\)/m\({}^{3}\)). These technologies are more expensive than the ones studied by [PERSON] et al. [27], and this can be related to the costs related to the reagents and with radiation. Furthermore, in [PERSON] et al. 's [27] study, the presence of catalyst and radiation seems to decrease the technologies' costs, and the use of single UVA with ozone is cheaper than catalyst with ozone and then UVA with catalyst and ozone. Catalytic ozonation was the most expensive treatment process, but this was not verified when photocatalytic ozonation was used. Moreover, this study suggests that the use of UVA makes the treatment more expensive but reduces the time of treatment, which can lead to smaller equipment and cheaper investment costs. When volcanic rocks are considered as the catalyst, the technology price decreases to 0.08 \(\upxi\)/m\({}^{3}\), which may indicate a significant decrease in operational costs when low-price catalysts are used and when UV radiation is not considered. Furthermore, [PERSON] et al. [117] calculated the costs of [PERSON] et al. [7] photocatalysis with TiO\({}_{2}\) for MP removal, achieving treatment costs of 100 \(\upxi\)/g (84 \(\upxi\)/g), and [PERSON] et al. [118] used sonochemical oxidation for methylparaben abatement. The cost is dependent on the chosen power density, but the cost varied from 197.92 \(\upxi\)/g to 527.78 \(\upxi\)/g (570-1050 \(\upxi\)/g). These studies report high expensive technologies, which present a huge disadvantage in using these treatments applied at industrial scale. [PERSON] et al. [112] achieved an MP removal comprised between 19.85% and 34.65%, using electrocatalysis with a BDD anode. The cost is related to the energy consumption, which is dependent on current density and was estimated to be between about 1.49 kWh/kg and 36 kWh/kg (0.19-4.59 \(\upxi\)/kg) and 0.26 kWh/m\({}^{3}\) and 7.24 kWh/m\({}^{3}\) (0.03-0.92 \(\upxi\)/m\({}^{3}\)). In fact, the real price for this technology is more expensive, since the costs with the BDD, the other electrodes, the electrolyte solution, which needs to be replaced several times (the costs related to reagents), etc. are not considered. Furthermore, these energy costs are only