Marina Badia-Fabregat

Evaluation of fungal- and photo-degradation as potential treatments for the removal of sunscreens BP3 and BP1.

Photodecomposition might be regarded as one of the most important abiotic factors affecting the fate of UV absorbing compounds in the environment and photocatalysis has been suggested as an effective method to degrade organic pollutants. However, UV filters transformation appears to be a complex process, barely addressed to date. The white rot fungus Trametes versicolor is considered as a promising alternative to conventional aerobic bacterial degradation, as it is able to metabolise a wide range of xenobiotics. This study focused on both degradation processes of two widely used UV filters, benzophenone-3 (BP3) and benzophenone-1 (BP1). Fungal treatment resulted in the degradation of more than 99% for both sunscreens in less than 24 h, whereas photodegradation was very inefficient, especially for BP3, which remained unaltered upon 24 h of simulated sunlight irradiation. Analysis of metabolic compounds generated showed BP1 as a minor by-product of BP3 degradation by T. versicolor while the main intermediate metabolites were glycoconjugate derivatives. BP1 and BP3 showed a weak, but significant estrogenic activity (EC50 values of 0.058 mg/L and 12.5 mg/L, respectively) when tested by recombinant yeast assay (RYA), being BP1 200-folds more estrogenic than BP3. Estrogenic activity was eliminated during T. versicolor degradation of both compounds, showing that none of the resulting metabolites possessed significant estrogenic activity at the concentrations produced. These results demonstrate the suitability of this method to degrade both sunscreen agents and to eliminate estrogenic activity.

Fungal treatment for the removal of antibiotics and antibiotic resistance genes in veterinary hospital wastewater

The emergence and spread of antibiotic resistance represents one of the most important public health concerns and has been linked to the widespread use of antibiotics in veterinary and human medicine. The overall elimination of antibiotics in conventional wastewater treatment plants is quite low; therefore, residual amounts of these compounds are continuously discharged to receiving surface waters, which may promote the emergence of antibiotic resistance. In this study, the ability of a fungal treatment as an alternative wastewater treatment for the elimination of forty-seven antibiotics belonging to seven different groups (β-lactams, fluoroquinolones, macrolides, metronidazoles, sulfonamides, tetracyclines, and trimethoprim) was evaluated. 77% of antibiotics were removed after the fungal treatment, which is higher than removal obtained in conventional treatment plants. Moreover, the effect of fungal treatment on the removal of some antibiotic resistance genes (ARGs) was evaluated. The fungal treatment was also efficient in removing ARGs, such as ermB (resistance to macrolides), tetW (resistance to tetracyclines), blaTEM (resistance to β-lactams), sulI (resistance to sulfonamides) and qnrS (reduced susceptibility to fluoroquinolones). However, it was not possible to establish a clear link between concentrations of antibiotics and corresponding ARGs in wastewater, which leads to the conclusion that there are other factors that should be taken into consideration besides the antibiotic concentrations that reach aquatic ecosystems in order to explain the emergence and spread of antibiotic resistance.

Identification of some factors affecting pharmaceutical active compounds (PhACs) removal in real wastewater. Case study of fungal treatment of reverse osmosis concentrate

Many technologies are being developed for the efficient removal of micropollutants from wastewater and, among them, fungal degradation is one of the possible alternative biological treatments. In this article, some factors that might affect pharmaceutically active compounds (PhACs) removal in a fungal treatment of real wastewater were identified in batch bioreactor treating reverse osmosis concentrate (ROC) from urban wastewater treatment plant (WWTP). We found that degradation of PhACs by Trametes versicolor was enhanced by addition of external nutrients (global removal of 44%). Moreover, our results point out that high aeration might be involved in the increase in the concentration of some PhACs. In fact, conjugation and deconjugation processes (among others) affect the removal assessment of emerging contaminants when working with real concentrations in comparison to experiments with spiked samples. Moreover, factors that could affect the quantification of micropollutants at lab-scale experiments were studied.

Use of stable isotope probing to assess the fate of emerging contaminants degraded by white-rot fungus

The widespread of emerging contaminants in the environment and their potential impact on humans is a matter of concern. White-rot fungi are cosmopolitan organisms able to remove a wide range of pharmaceuticals and personal care products (PPCP) through cometabolism (i.e. laccases and peroxidases) or detoxification mechanisms (i.e. cytochrome P450 system). However, the use of PPCP as carbon source for these organisms is largely unexplored. Here, we used carbon stable isotope tracer experiments to assess the fate of anti-inflammatory diclofenac (DCF) and UV filter benzophenone-3 (BP3) during degradation by Trametes versicolor. The comparison between carbon isotopic composition of emitted carbon dioxide from 13C-labelled DCF ([acetophenyl ring-13C6]-DCF) and 13C-BP3 ([phenyl-13C6]-BP3) versus their 12C-homologue compounds showed mineralization of about 45% and 10% of the 13C contained in their respective molecules after 9 days of incubation. The carbon isotopic composition of the bulk biomass and the application of amino acid-stable isotope probing (SIP) allowed distinguishing between incorporation of 13C from BP3 into amino acids, which implies the use of this emerging contaminant as carbon source, and major intracellular accumulation of 13C from DCF without implying the transformation of its labelled phenyl ring into anabolic products. A mass balance of 13C in different compartments over time provided a comprehensive picture of the fate of DCF and BP3 across their different transformation processes. This is the first report assessing biodegradation of PPCP by SIP techniques and the use of emerging contaminants as carbon source for amino acid biosynthesis.

Study of the effect of the bacterial and fungal communities present in real wastewater effluents on the performance of fungal treatments

The use of the ligninolytic fungi Trametes versicolor for the degradation of micropollutants has been widely studied. However, few studies have addressed the treatment of real wastewater containing pharmaceutically active compounds (PhAC) under non-sterile conditions. The main drawback of performing such treatments is the difficulty for the inoculated fungus to successfully compete with the other microorganisms growing in the bioreactor. In the present study, several fungal treatments were performed under non-sterile conditions in continuous operational mode with two types of real wastewater effluent, namely, a reverse osmosis concentrate (ROC) from a wastewater treatment plant and a veterinary hospital wastewater (VHW). In all cases, the setup consisted of two parallel reactors: one inoculated with T. versicolor and one non-inoculated, which was used as the control. The main objective of this work was to correlate the operational conditions and traditional monitoring parameters, such as laccase activity, with PhAC removal and the composition of the microbial communities developed inside the bioreactors. For that purpose a variety of biochemical and molecular biology analyses were performed: phospholipid fatty acids analysis (PLFA), quantitative PCR (qPCR) and denaturing gradient gel electrophoresis (DGGE) followed by sequencing. The results show that many indigenous fungi (and not only bacteria, which were the focus of the majority of previously published research) can successfully compete with the inoculated fungi (i.e., Trichoderma asperellum overtook T. versicolor in the ROC treatment). We also showed that the wastewater origin and the operational conditions had a stronger impact on the diversity of microbial communities developed in the bioreactors than the inoculation or not with T. versicolor.

Suspect screening of emerging pollutants and their major transformation products in wastewaters treated with fungi by liquid chromatography coupled to a high resolution mass spectrometry

A new approach for the screening of 33 pharmaceuticals and 113 of their known transformation products in wastewaters was developed. The methodology is based on the analysis of samples by liquid chromatography coupled to high resolution mass spectrometry (HRMS) followed by data processing using specific software and manual confirmation. A home-made library was built with the transformation products reported in literature for the target pharmaceuticals after treatment with various fungi. The method was applied to the search of these contaminants in 67 samples generated along treatment of wastewaters with white-rot fungus Trametes versicolor. The screening methodology allowed the detection of different transformation products (TPs) generated from degradation of parent compounds after fungal treatment. This approach can be a useful tool for the rapid screening and tentative detection of emerging contaminants during water treatment in both full and batch-scale studies when pure standards are not available.

The role of sorption processes in the removal of pharmaceuticals by fungal treatment of wastewater

The contribution of the sorption processes in the elimination of pharmaceuticals (PhACs) during the fungal treatment of wastewater has been evaluated in this work. The sorption of four PhACs (carbamazepine, diclofenac, iopromide and venlafaxine) by 6 different fungi was first evaluated in batch experiments. Concentrations of PhACs in both liquid and solid (biomass) matrices from the fungal treatment were measured. Contribution of the sorption to the total removal of pollutants ranged between 3% and 13% in relation to the initial amount. The sorption of 47 PhACs in fungi was also evaluated in a fungal treatment performed in 26days in a continuous bioreactor treating wastewater from a veterinary hospital. PhACs levels measured in the fungal biomass were similar to those detected in conventional wastewater treatment (WWTP) sludge. This may suggest the necessity of manage fungal biomass as waste in the same manner that the WWTP sludge is managed.

Overview on Pilot-Scale Treatments and New and Innovative Technologies for Hospital Effluent

In this chapter, pilot-scale studies and some innovative lab-scale investigations on hospital wastewater (HWW) treatment are presented. Pilot-scale systems usually consist of a first biological treatment to remove organic matter, nutrients, and some pharmaceutically active compounds (PhACs) followed by a physicochemical treatment to increase removal of PhACs and other micropollutants (MPs). Biological treatments are usually advanced treatments such as membrane bioreactors (MBRs), which allow longer residence time of microorganisms, and thus, more suitable conditions for the removal of micropollutants such as PhACs. Moreover, membranes also sanitize the effluent, retaining the pathogenic microorganisms and reducing release of antibiotic resistance genes (ARG). On the other hand, ozonation and activated carbon (AC) are the most common alternatives chosen as a polishing step. Research is actively working on innovative treatments, such as photocatalysis, to reduce the treatment cost, which is the major drawback for implementation of dedicated (in situ) degradation treatments of PhACs in HWW.

UV Filters Biodegradation by Fungi, Metabolites Identification and Biological Activity Assessment

Organic UV filters used in cosmetics and sunlight protection of materials are considered emerging contaminants. These xenobiotic compounds occur in the environment in relevant concentrations and display critical properties such as environmental persistence and bioaccumulation. They enter the environment mainly through the liquid effluent of wastewater treatment plants (WWTPs), but, due to their high hydrophobicity, they are also adsorbed in WWTP sludge, that is, eventually spread on agricultural fields as fertilizer. The treatment of WWTP sludge with the white-rot fungi Trametes versicolor has emerged as a feasible alternative to current conventional treatment processes to degrade them in a range from 87% in the case of 3-(40-methylbenzylidene) camphor (4-MBC) to 100% of benzophenone-3 (BP3) and its metabolite 4,40-dihydroxybenzophenone (4DHB). When treating the sewage sludge to remove sunscreens content, it is crucial to establish the biological activity profile along the process. Oestrogenic activity was eliminated by the T. versicolor treatment, indicating that none of the resulting M. Badia-Fabregat, T. Vicent and P. Blanquez Departament d’Enginyeria Quimica, Escola d’Enginyeria, Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona, Spain G. Caminal Grupo de biocatalisis Aplicada y biodegradacion, IQAC-CSIC, C/Jordi Girona 18-26, 08034 Barcelona, Spain P. Gago-Ferrero, A. Olivares, B. Pina and M.S. Diaz-Cruz (*) Departament de Quimica Ambiental, IDAEA-CSIC, C/ Jordi Girona 18-26, 08034 Barcelona, Spain e-mail: silvia.diaz@idaea.csic.es D. Barcelo Departament de Quimica Ambiental, IDAEA-CSIC, C/ Jordi Girona 18-26, 08034 Barcelona, Spain Catalan Institute for Water Research (ICRA), Parc Cientific i Tecnologic de la Universitat de Girona, C/ Emili Grahit, 101 Edifici H2O, 17003 Girona, Spain T. Vicent et al. (eds.), Emerging Organic Contaminants in Sludges: Analysis, Fate and Biological Treatment, Hdb Env Chem (2013) 24: 215–240, DOI 10.1007/698_2012_157, # Springer-Verlag Berlin Heidelberg 2012, Published online: 4 May 2012 215 metabolites possessed significant oestrogenic activity at the produced concentrations. These results demonstrate the suitability of fungi to degrade sunscreen agents and eliminate their oestrogenic activity.

Fungal-Mediated Biodegradation of Ingredients in Personal Care Products

Many efforts have been devoted in developing technologies to remove emerging organic pollutants from freshwater systems. This chapter examined the applications of the environmental friendly technology based on fungal-mediated treatment for the degradation of ingredients in personal care products (PCPs), which are frequently detected at relevant concentrations in the aquatic environment. PCPs are daily-use products used in large quantity that includes several groups of substances (UV filters, preservatives, fragrances, etc.). Removal efficiencies reported varied significantly among different experimental set-up, organic substance, and type of fungi. The mechanisms and factors governing the degradation of PCPs by fungi, mainly white-rot fungi and their specific lignin-modifying enzymes, are reviewed and discussed. Beyond, the identification of the intermediate products and metabolites produced as well as the degradation pathways available for some PCPs are presented.