## 4 Toxicological Studies of Parabens Abatement
[91], which showed about 80% light inhibition after treatment, which represent the worst result of these studies. Moreover, photolytic ozonation seems to be worse than photocatalytic ozonation, which may suggest a good behavior of catalysts presence regarding the toxicity elimination. This may also suggest that the presence of catalyst can be an interesting advantage in wastewater treatment, since it can lower the treatment costs (when compared to single ozone) [27] and can also enhance the toxicity decrease. For _C. fluminea_ total mortality, this was reduced to zero in almost all experiments in 72 h in the study of [PERSON] et al. [121], which was concordant with the results of [PERSON] et al. [27], but [PERSON] et al. [26] obtainedmortality of 29% and 21% for single ozonation and catalytic ozonation with TiO\({}_{2}\). Photocatalysis showed the worst results once again, with the worst clam mortality of 55% [91]. These studies show a better behavior of photocatalytic ozonation and photolytic ozonation than catalytic ozonation and photocatalysis when doped TiO\({}_{2}\) catalysts were used, which showed even worse results. In fact, this is interesting, since the use of ozone should easily generate intermediaries from parabens' abatement that can be more toxic than the parent compounds. However, these contaminants may have been completely degraded without affecting the toxicity. Furthermore, the behavior of photocatalytic ozonation regarding this species is similar to the one observed for _A. fischeri_. For _L. sativum_, [PERSON] et al. [121] achieved the best GI of 112%, [PERSON] et al. [26] of 90%, [PERSON] et al. [91] of 70%, and best GI of 112% for [PERSON] et al. [27] study, which presents similar results and behaviors than the observed for the other species. [PERSON] et al. [103] treated the same solution than [PERSON] et al. [26; 27; 91; 121] but used catalytic ozonation with N-TiO\({}_{2}\) and single ozone. The authors achieved better results of 30%, 30%, and 20% for C. _fluminea_ mortality using ozonation, catalytic ozonation with TiO\({}_{2}\), and catalytic ozonation with N-TiO\({}_{2}\), respectively, while the initial mortality was 84% in 48 h. Regarding _L. sativum_, it showed an initial GI of 41.8% and had GI of 74.6%, 108.6%, and 123.4% for O\({}_{3}\), O\({}_{3}\) + TiO\({}_{2}\) and O\({}_{3}\) + N-TiO\({}_{2}\). The toxicity evaluation using _A. fischeri_ showed an initial LI of 95.6% and LI of 70%, 73.9%, and 63% for O\({}_{3}\), O\({}_{3}\) + TiO\({}_{2}\), and O\({}_{3}\) + N-TiO\({}_{2}\). In fact, compared to [PERSON] et al. [26], the results obtained by [PERSON] et al. [103] were the worst, which may indicate a weak performance of N-TiO\({}_{2}\) for toxicity decreased when compared to TiO\({}_{2}\) doped with noble metals. [PERSON] et al. [75] used photocatalysis for MP removal, and the toxicity was evaluated using _Artemta franciscana nauplii_. In this study, the formation of more toxic intermediaries occurred when the MP removal was about 39%, in which an increase of 10% in toxicity was observed. However, after the complete MP removal, the intermediaries were also removed, and the solution's toxicity was similar to the initial one. Furthermore, [PERSON] et al. [31] used cross seeds for toxicity evaluation of an MP solution that was treated with photo-Fenton-like reaction (using best operational conditions). In fact, the observed inhibition was about 1% for the treated water and about 30% for the initial MP solution. [PERSON] et al. [30] used several AOPs for the degradation of a mixture of MP, EP, PP, BuP, and BeP at 10 mg/L each. Considering the treatments, regarding _A. fischeri_, the worst result was achieved for photocatalysis using several catalysts that had LI higher than 80%, and the best results occurred for ozone with Au-TiO\({}_{2}\) with a LI of 31.4%. For _L. sativum_, the worst GI was obtained by 43% for photocatalysis with TiO\({}_{2}\) and the best was 112% for O\({}_{3}\) with UVA radiation and Ag-TiO\({}_{2}\). Furthermore, the toxicity of _C.