Besides COD was determined before and
Besides, COD was determined before and after laccase treatment on real sample, highlighting a consistent reduction, close to 36%. The results were consistent with residual analytes concentration determined by SBSE-TDU-GC-MS and in line with the measured PR. It must be stressed that, although residual COD is still relatively high, the partial ASA 404 of this parameter mediated by laccases could improve the final efficiency of the process, since the metabolites produced are usually more efficiently biodegraded by subsequent treatments (Nakamura and Mtui, 2003).
3.3.2. Ecotoxicity and estrogenic activity evaluation
Knowing the actual amount of compounds that potentially come into contact with aquatic organisms and human beings is important but not sufficient to predict a reasonable risk assessment and bioassays are useful tools to integrate the analytical data measuring the effects of complex mixtures. Besides, primary macronutrients should be also considered that synergistic or antagonistic interactions among chemical substances may occur. Actually, a mixture of compounds is often more toxic than expected by summing the effects of each single component (Kortenkamp et al., 2007). Thus, the risk associated to real wastewaters could be deeply underestimated without additional toxicological information obtained by means of bioassays, able to describe the ecotoxicity and the estrogenic activity ascribable to a certain sample.