## 3 Results and Discussion
### Physico-Chemical Characterisation of Textile Effluent Samples
Several derivatives from bisphenol compounds are endocrine disruptors because they are similar to estrogen, raising serious concerns about the effects on populations, since it is a compound widely used in industry [32; 33]. [PERSON] and [PERSON] [34] suggest the compounds butyl-octyl-phtalate and diisooctylphtalate as being the most toxic compounds of the untreated textile effluent. The amines are used in the production of dyes and textile products, while the linear aliphatic alcohols are applied as solvents and antifoaming agents [34]. \begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline  & **Raw Effluent (RE)** & **Treated Effluent 1 (TE1)** & **Treated Effluent 2 (TE2)** \\ \hline
**Apparent Colour** & Grey & Green & Green \\ \hline
**Colour (PtCo)** & 560 & 156 & 198 \\ \hline
**pH** & 3.33 & 7.36 & 6.76 \\ \hline
**TDS (ppm)** & 1215 & 1539 & 2322 \\ \hline
**Conductivity (\(\mu\)S cm\({}^{-1}\))** & 2343 & 3085 & 4270 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Characterisation of the effluent used in the toxicity tests. Phenol is usually used as a disinfectant and in the production of phenolic resins, like bisphenol A and caprolactam [35]. [PERSON] and [PERSON] [36] evaluated the toxicity of phenol to several aquatic organisms from different groups (a bacterial culture, the algae _Scenedesmus quadricauda_, the crustacean _Daphnia pulex_ and the fish _Oncorhynchus mykiss_). They showed that phenol is more toxic to fish (EC\({}_{50,48\,\mathrm{h}}=13.1\) mg L\({}^{-1}\)), followed by the crustacean (EC\({}_{50,48\,\mathrm{h}}=25.0\) mg L\({}^{-1}\)), the green algae (EC\({}_{50,24\,\mathrm{h}}=403.0\) mg L\({}^{-1}\)) and finally the bacterial culture (EC\({}_{50,120\,\mathrm{h}}=510.0\) mg L\({}^{-1}\)). These authors also assessed the toxicity of formaldehyde, which was more toxic to the crustacean, followed by algae and the bacterial culture. These results, although dealing with individual substances and not with the real effluent itself, reinforces the importance of an ecotoxicological evaluation of different taxonomic groups since the sensitivity of each organism differs with the different components of the effluent [36]. The concentrations of phenol in the RE (0.0325 \(\mathrm{\SIUnitSymbolMicro m}\) L\({}^{-1}\)) and in the TE1 (0.0250 \(\mathrm{\SIUnitSymbolMicro m}\) L\({}^{-1}\)) were below the emission limit values (ELV) for wastewater and treated effluent discharged (0.5 mg L\({}^{-1}\) C\({}_{6}\)H\({}_{5}\)OH), referred to, for example, in the Portuguese Law by Decree n\({}^{\circ}\) 236/98 of 1 August [30]. If we compare the concentration of phenol in our samples (Table 2) with the values of toxicity from the study of [PERSON] and [PERSON] [36], neither the raw effluent nor the treated effluent presented an ecotoxicological risk for the fish or crustacean. Triclosan is used as antibacterial and antifungal agent. [PERSON] et al. [37] studied the toxicity of tridosan to activated-sludge microorganisms, algae and the aquatic plant _L. gibba_. Although this compound is used as an antibacterial, no toxic effects were recorded for the activated-sludge