How should ecohazard of micropollutants in wastewater be gauged? Using bioassays to profile alternative tertiary treatments

Abstract

The research on emerging pollutants in wastewater has become a worldwide issue of increasing environmental concern, especially considering the growing interest in wastewater reuse. However, the latter implies additional post-treatment after the conventional activated sludge processes, in order to produce a safer effluent. Our work aimed at determining the efficiency of reducing the toxicity associated with organic micropollutants (OMPs) in secondary wastewater effluents, using 3 different post-treatment technologies (granular activated carbon (GAC), sand biofiltration and UV irradiation): in particular, target chemical analysis of the OMPs most commonly founded in wastewater was coupled with effect-based assays (estrogenicity and mutagenicity). While chemical analysis assessed satisfactory performances for all 3 technologies in the abatement of selected OMPs, biological assays evidenced another perspective: both GAC and sand biofilters were significantly able to make the estrogenic load plummet; however, the UV system was ineffective in estrogenicity abatement, and its effluent exhibited also a slight mutagenicity, likely due to photo-transformation by-products. These results indicate that a synergistic combination of chemical analysis and biological assays can drive to a proper gauging of post-treatment technologies, taking into account not only the removal of OMPs, but also their overall toxicity.

Chemometric Evaluation of WWTPs’ Wastewaters and Receiving Surface Waters in Bulgaria

“…The new quality of information has been given by adding bioassays [53] and chemometric studies to a range of tools applicable in this important evaluation of WWTP efficiencies. Algal, bacterial and plant tests were the most often used biological tools in such monitoring, however they always seemed to have specific limitations, being of acute character and using, most often, organisms of lower trophic level [54].…”

“…Instrumental conditions for ICP-MS measurement (Perkin-Elmer SCIEX DRC-e).Determined isotopes of trace elements27 Al,51 V,52 Cr,54,57 Fe,59 Co, 55 Mn, 60,62 Ni, 63,65 Cu,64,66,68 Zn,…”

Evaluation of the Effectiveness of Treatments to Remove Per- and Polyfluoroalkyl Substances from Water—Are We Using the Right Approach? Proposal of a Paradigm Shift from “Chemical Only” towards an Integrated Bio-Chemical Assessment

“…For instance, in order to evaluate the effectiveness of tertiary wastewater treatment on organic micropollutants, Papa et al [61] combined chemical analysis with bioassays to investigate estrogenicity and mutagenicity. Interestingly, their work pointed out that bioassays were more sensitive to the overall toxicity of the effluent, even when the chemical analysis showed a very good performance of the process on micropollutant removal [61]. Similarly, Bertanza et al [62] proposed an integrated bio-chemical monitoring of ozonation of WWTP effluents for the removal of endocrine disruptor compounds.…”

Beyond the Black Box of Life Cycle Assessment in the Wastewater Treatment Plants: Which Help from the Bioassays?

“…Since it is impossible to measure every pollutant (primary and secondary) present in an emission, non-targeted analyses have been receiving more attention, in an effort to describe these complex mixtures more accurately, while going beyond the lists of standards outlined in regulations and guidelines [23][24][25]. The execution of bioassays (possibly organized in batteries, including various modes of toxicity action, biological complexity systems, and trophic roles) has been increasingly proposed, which is even more significant [26][27][28][29][30][31][32]. Rather than focusing on a subset of known contaminants, this final strategy promotes the biological response by including both known and unknown chemicals in the mixture.…”

“…Rather than focusing on a subset of known contaminants, this final strategy promotes the biological response by including both known and unknown chemicals in the mixture. Several researchers have been applied this bioanalytical approach on the wastewater [30][31][32][33][34], drinking water [35][36][37] and surface water [38].…”