Pharmaceuticals removal and microbial community assessment in a continuous fungal treatment of non-sterile real hospital wastewater after a coagulation-flocculation pretreatment

The potential contribution of aquatic wildlife to antibiotic resistance dissemination in freshwater ecosystems: A review

Antibiotic resistance (AR) is one of the major health threats of our time. The presence of antibiotics in the environment and their continuous release from sewage treatment plants, chemical manufacturing plants and animal husbandry, agriculture and aquaculture, result in constant selection pressure on microbial organisms. This presence leads to the emergence, mobilization, horizontal gene transfer and a selection of antibiotic resistance genes, resistant bacteria and mobile genetic elements. Under these circumstances, aquatic wildlife is impacted in all compartments, including freshwater organisms with partially impermeable microbiota. In this narrative review, recent advancements in terms of occurrence of antibiotics and antibiotic resistance genes in sewage treatment plant effluents source compared to freshwater have been examined, occurrence of antibiotic resistance in wildlife, as well as experiments on antibiotic exposure. Based on this current state of knowledge, we propose the hypothesis that freshwater aquatic wildlife may play a crucial role in the dissemination of antibiotic resistance within the environment. Specifically, we suggest that organisms with high bacterial density tissues, which are partially isolated from the external environment, such as fishes and amphibians, could potentially be reservoirs and amplifiers of antibiotic resistance in the environment, potentially favoring the increase of the abundance of antibiotic resistance genes and resistant bacteria. Potential avenues for further research (trophic transfer, innovative exposure experiment) and action (biodiversity eco-engineering) are finally proposed.

Removal of pharmaceutical compounds and toxicology study in wastewater using Malaysian fungal Ganoderma lucidum

Elevated usage of pharmaceutical products leads to the accumulation of emerging contaminants in sewage. In the current work, Ganoderma lucidum (GL) was used to remove pharmaceutical compounds (PCs), proposed as a tertiary method in sewage treatment plants (STPs). The PCs consisted of a group of painkillers (ketoprofen, diclofenac, and dexamethasone), psychiatrists (carbamazepine, venlafaxine, and citalopram), beta-blockers (atenolol, metoprolol, and propranolol), and anti-hypertensives (losartan and valsartan). The performance of 800 mL of synthetic water, effluent STP, and hospital wastewater (HWW) was evaluated. Parameters, including treatment time, inoculum volume, and mechanical agitation speed, have been tested. The toxicity of the GL after treatment is being studied based on exposure levels to zebrafish embryos (ZFET) and the morphology of the GL has been observed via Field Emission Scanning Electron Microscopy (FESEM). The findings conclude that GL can reduce PCs from <10% to >90%. Diclofenac and valsartan are the highest (>90%) in the synthetic model, while citalopram and propranolol (>80%) are in the real wastewater. GL effectively removed pollutants in 48 h, 1% of the inoculum volume, and 50 rpm. The ZFET showed GL is non-toxic (LC50 is 209.95 mg/mL). In the morphology observation, pellets GL do not show major differences after treatment, showing potential to be used for a longer treatment time and to be re-useable in the system. GL offers advantages to removing PCs in water due to their non-specific extracellular enzymes that allow for the biodegradation of PCs and indicates a good potential in real-world applications as a favourable alternative treatment.

Comprehensive analysis of a widely pharmaceutical, furosemide, and its degradation products in aquatic systems: Occurrence, fate, and ecotoxicity

Many pharmaceutical compounds end up in the environment due to incomplete removal by wastewater treatment plants (WWTPs). Some compounds are sometimes present in significant concentrations and therefore represent a risk to the aquatic environment. Furosemide is one of the most widely used drugs in the world. Considered as an essential drug by the World Health Organization, this powerful loop diuretic is used extensively to treat hypertension, heart and kidney failure and many other purposes. However, this important consumption also results in a significant release of furosemide in wastewater and in the receiving environment where concentrations of a few hundred ng/L to several thousand have been found in the literature, making furosemide a compound of great concern. Also, during its transport in wastewater systems and WWTPs, furosemide can be degraded by various processes resulting in the production of more than 74 by-products. Furosemide may therefore present a significant risk to ecosystem health due not only to its direct cytotoxic, genotoxic and hepatotoxic effects in animals, but also indirectly through its transformation products, which are poorly characterized. Many articles classify furosemide as a priority pollutant according to its occurrence in the environment, its persistence, its elimination by WWTPs, its toxicity and ecotoxicity. Here, we present a state-of-the-art review of this emerging pollutant of interest, tracking it, from its consumption to its fate in the aquatic environment. Discussion points include the occurrence of furosemide in various matrices, the efficiency of many processes for the degradation of furosemide, the subsequent production of degradation products following these treatments, as well as their toxicity.

Next-generation hybrid technologies for the treatment of pharmaceutical industry effluents

Water and industries are intangible units of the globe that are always set to meet the population's demand. The global population depends on one-third of freshwater increasing the demand. The increase in population along with urbanization has polluted the fresh water resources. The pharmaceutical industry is marked as an emerging contaminant of water pollution. The most common type of pharmaceutical drugs that are detected in the environment includes antibiotics, analgesics, NSAIDs, and pain-relieving drugs. These drugs alter the food chain of the organisms causing chaos mainly in the marine ecosystem. Pharmaceutical drugs are found only in shallow amounts (ng/mg) they have a huge impact on the living system. The consumption of water contaminated with pharmaceutical ingredients can disrupt reproduction, hormonal imbalance, cancer, and respiratory problems. Various methods are used to remove these chemicals from the environment. In this review, we mainly focused on the emerging hybrid technologies and their significance in the effective treatment of pharmaceutical wastewater. This review paper primarily elaborates on the merits and demerits of existing conventional technologies helpful in developing integrated technologies for the modern era of pharmaceutical effluent treatment. This review paper further in detail discusses the various strategies of eco-friendly bioremediation techniques namely biostimulation, bioaugmentation, bacterial degradation, mycoremediation, phytoremediation, and others for the ultimate removal of pharmaceutical contaminants in wastewater. The review makes clear that targeted and hybrid solutions are what the world will require in the future to get rid of these pharmacological prints.

Coagulation pretreatment coupled with indigenous microalgal-bacterial consortium system for on-site treatment of rural black wastewater

Improper treatment of rural black wastewater (RBW) presents substantial challenges, including the wastage of resource, environmental contamination, and economic consequences. This study proposed an integrated process for RBW treatment, consisting of coagulation/flocculation (C/F) pretreatment and subsequent inoculation of indigenous microalgal-bacterial consortium (IMBC) for nitrogen recovery, namely C/F-IMBC process. Specifically, the optimal C/F conditions (polyaluminium chloride of 4 g/l, polyacrylamide of 50 mg/l, and pH of 6) were determined through a series of single-factor experiments, considering CN, turbidity, and dissolved organic matter (DOM) removal, economic cost, and potential influence on the water environment. Compared to the sole IMBC system for RBW treatment, the proposed C/F-IMBC process exhibited a remarkable 1.23-fold increase in microalgal growth and a substantial 17.6-22.6 % boost in nitrogen recovery. The altered RBW characteristic induced by C/F pretreatment was supposed to be responsible for the improved system performance. In particular, the abundance of DOM was decreased and its composition was simplified after C/F pretreatment, based on the analysis for excitation-emission matrices with parallel factor and gas chromatography-mass spectrometry, thus eliminating the potential impacts of toxic DOM components (e.g., Bis(2-ethylhexyl) phthalate) on IMBC activity. It should also be noted that C/F pretreatment modified microbial community structure as well, thereby regulating the expression of nitrogen-related genes and enhancing the system nitrogen recovery capacity. For instance, the functional Cyanobacteria responsible for nutrient recovery was enriched by 1.95-fold and genes involved in the assimilatory nitrate reduction to ammonia pathway were increased by 1.52-fold. These fundamental findings are expected to offer insights into the improvement of DOM removal and nitrogen recovery for IMBC-based wastewater treatment system, and provide valuable guidance for the development of sustainable on-site RBW treatment technologies.

Hydroxylated transformation products of pharmaceutical active compounds: Generation from processes used in wastewater treatment plants and its environmental monitoring

Pharmaceutical active compounds (PhACs) are organic pollutants detected in wastewater and aquatic environments worldwide in concentrations ranging from ng L-1 to μg L-1. Wastewater effluents containing PhACs residues is discharged in municipal sewage and, subsequently collected in municipal wastewater treatment plants (WWTPs) where are not entirely removed. Thus, PhACs and its transformation products (TPs) are discharged into water bodies. In the current work, the transformation of PhACs under treatments used in municipal WWTPs such as biological, photolysis, chlorination, and ozonation processes was reviewed. Data set of the major transformation pathways were obtained of studies that performed the PhACs removal and TPs monitoring during batch-scale experiments using gas and liquid chromatography coupled with tandem mass spectrometry (GC/LC-MS/MS). Several transformation pathways as dealkylation, hydroxylation, oxidation, acetylation, aromatic ring opening, chlorination, dehalogenation, photo-substitution, and ozone attack reactions were identified during the transformation of PhACs. Especially, hydroxylation reaction was identified as transformation pathway in all the processes. During the elucidation of hydroxylated TPs several isobaric compounds as monohydroxylated and dihydroxylated were identified. However, hydroxylated TPs monitoring in wastewater and aquatic environments is a topic scarcely studied due to that has no environmental significance, lack of available analytic standars of hydroxylated TPs and lack of analytic methods for their identification. Thus, screening strategy for environmental monitoring of hydroxylated TPs was proposed through target and suspect screening using GC/LC-MS/MS systems. In the next years, more studies on the hydroxylated TPs monitoring are necessary for its detection in WWTPs effluents as well as studies on their environmental effects in aquatic environments.

Continuous operation of fungal wheel reactor based on solid-state fermentation for the removal of pharmaceutical and personal care products

Wood-rotting fungi and their enzymatic systems represent promising biocatalysts for the removal of pharmaceuticals and personal care products (PPCPs) from wastewater. We designed a fungal wheel reactor (FWR) based on solid-state fermentation (SSF) of Trametes versicolor and a lignocellulosic substrate, which was used as an immobilization carrier for fungal biomass and the sole initial nutrient source for producing fungal oxidative enzymes. Three pharmaceutical and personal care products, acetaminophen, bisphenol A and carbamazepine, were spiked into the synthetic wastewater and the treatment was carried out under non-sterile conditions. Acetaminophen was completely removed from the FWR until laccase was observed. The acetaminophen removal efficiency was retrieved by replacing the fungal wheel with fresh SSF products. Bisphenol A and carbamazepine were removed via enzymatic activity and adsorption. When the fungal wheel was replaced, acetaminophen began to be completely removed, even after laccase depletion. The microbial community analysis indicated that the continuous removal of acetaminophen was mainly due to the high proportion of T. versicolor. The relative abundance of the co-occurring microbial community might be responsible for the divergence in acetaminophen removal between two of fungal wheel-replaced reactors. Overall, FWRs are promising tools for the removal of PPCPs by highly reactive enzymatic mechanisms as well as adsorption on the carrier surface. By replacing SSF and settled microbial communities, FWRs may continuously contribute to bioremediation over a long-term period.

Filamentous fungi for sustainable remediation of pharmaceutical compounds, heavy metal and oil hydrocarbons

This review presents a comprehensive summary of the latest research in the field of bioremediation with filamentous fungi. The main focus is on the issue of recent progress in remediation of pharmaceutical compounds, heavy metal treatment and oil hydrocarbons mycoremediation that are usually insufficiently represented in other reviews. It encompasses a variety of cellular mechanisms involved in bioremediation used by filamentous fungi, including bio-adsorption, bio-surfactant production, bio-mineralization, bio-precipitation, as well as extracellular and intracellular enzymatic processes. Processes for wastewater treatment accomplished through physical, biological, and chemical processes are briefly described. The species diversity of filamentous fungi used in pollutant removal, including widely studied species of Aspergillus, Penicillium, Fusarium, Verticillium, Phanerochaete and other species of Basidiomycota and Zygomycota are summarized. The removal efficiency of filamentous fungi and time of elimination of a wide variety of pollutant compounds and their easy handling make them excellent tools for the bioremediation of emerging contaminants. Various types of beneficial byproducts made by filamentous fungi, such as raw material for feed and food production, chitosan, ethanol, lignocellulolytic enzymes, organic acids, as well as nanoparticles, are discussed. Finally, challenges faced, future prospects, and how innovative technologies can be used to further exploit and enhance the abilities of fungi in wastewater remediation, are mentioned.

Fungal treatment of agricultural washing wastewater: Comparison between two operational strategies

Agricultural washing wastewater (AWW) is an important source of pesticides that, given its intrinsic characteristics, has a high potential to be treated by fungal bioremediation using white rot fungi. In the present study, two AWW treatment strategies were compared: a fluidized-bed reactor (FBR) with T. versicolor pellets and a rotating drum bioreactor (RDB) with T. versicolor immobilized on wood. The RDB effluent showed better results in all studied parameters compared to those of the FBR, including pesticide removal (87%), toxicity, laccase activity, COD, absorbance and microbial communities. Additionally, the fungal assemblage showed that T. versicolor was successfully immobilized in the RDB, which triggered a major shift in the initial community. Afterwards, solid by-products were treated in a fungal biopile-like system reaching high biodegradation rates. Therefore, this study validates the fungal RDB as a viable alternative for AWW treatment, opening up the possibility of a further in-situ and full-scale application.

Critical review of technologies for the on-site treatment of hospital wastewater: From conventional to combined advanced processes

This review aims to assess different technologies for the on-site treatment of hospital wastewater (HWW) to remove pharmaceutical compounds (PhCs) as sustances of emerging concern at a bench, pilot, and full scales from 2014 to 2020. Moreover, a rough characterisation of hospital effluents is presented. The main detected PhCs are antibiotics and psychiatric drugs, with concentrations up to 1.1 mg/L. On the one hand, regarding the presented technologies, membrane bioreactors (MBRs) are a good alternative for treating HWW with PhCs removal values higher than 80% in removing analgesics, anti-inflammatories, cardiovascular drugs, and some antibiotics. Moreover, this system has been scaled up to the pilot plant scale. However, some target compounds are still present in the treated effluent, such as psychiatric and contrast media drugs and recalcitrant antibiotics (erythromycin and sulfamethoxazole). On the other hand, ozonation effectively removes antibiotics found in the HWW (>93%), and some studies are carried out at the pilot plant scale. Even though, some families, such as the X-ray contrast media, are recalcitrant to ozone. Other advanced oxidation processes (AOPs), such as Fenton-like or UV treatments, seem very effective for removing pharmaceuticals, Antibiotic Resistance Bacteria (ARBs) and Antibiotic Resistance Genes (ARGs). However, they are not implanted at pilot plant or full scale as they usually consider extra reactants such as ozone, iron, or UV-light, making the scale-up of the processes a challenging task to treat high-loading wastewater. Thus, several examples of biological wastewater treatment methods combined with AOPs have been proposed as the better strategy to treat HWW with high removal of PhCs (generally over 98%) and ARGs/ARBs (below the detection limit) and lower spending on reactants. However, it still requires further development and optimisation of the integrated processes.

Current Challenges for Biological Treatment of Pharmaceutical-Based Contaminants with Oxidoreductase Enzymes: Immobilization Processes, Real Aqueous Matrices and Hybrid Techniques

The worldwide access to pharmaceuticals and their continuous release into the environment have raised a serious global concern. Pharmaceuticals remain active even at low concentrations, therefore their occurrence in waterbodies may lead to successive deterioration of water quality with adverse impacts on the ecosystem and human health. To address this challenge, there is currently an evolving trend toward the search for effective methods to ensure efficient purification of both drinking water and wastewater. Biocatalytic transformation of pharmaceuticals using oxidoreductase enzymes, such as peroxidase and laccase, is a promising environmentally friendly solution for water treatment, where fungal species have been used as preferred producers due to their ligninolytic enzymatic systems. Enzyme-catalyzed degradation can transform micropollutants into more bioavailable or even innocuous products. Enzyme immobilization on a carrier generally increases its stability and catalytic performance, allowing its reuse, being a promising approach to ensure applicability to an industrial scale process. Moreover, coupling biocatalytic processes to other treatment technologies have been revealed to be an effective approach to achieve the complete removal of pharmaceuticals. This review updates the state-of-the-art of the application of oxidoreductases enzymes, namely laccase, to degrade pharmaceuticals from spiked water and real wastewater. Moreover, the advances concerning the techniques used for enzyme immobilization, the operation in bioreactors, the use of redox mediators, the application of hybrid techniques, as well as the discussion of transformation mechanisms and ending toxicity, are addressed.

Fungal bioremediation of agricultural wastewater in a long-term treatment: biomass stabilization by immobilization strategy

Fungal bioremediation emerges as an effective technology for pesticide treatment, but its successful implementation depends on overcoming the problem of microbial contamination. In this regard, fungal immobilization on wood seems to be a promising strategy, but there are two main drawbacks: the predominant removal of pesticides by sorption and fungal detachment. In this study, agricultural wastewater with pesticides was treated by Trametes versicolor immobilized on wood chips in a rotary drum bioreactor (RDB) for 225 days, achieving fungal consolidation and high pesticide biodegradation through two main improvements: the use of a more favorable substrate and the modification of operating conditions. Fungal community dynamic was assessed by denaturing gradient gel electrophoresis (DGGE) analysis and subsequent prominent band sequencing, showing a quite stable community in the RDB, mainly attributed to the presence of T. versicolor. Pesticide removals were up to 54 % diuron and 48 % bentazon throughout the treatment. Afterwards, pesticide-contaminated wood chips were treated by T. versicolor in a solid biopile-like system. Hence, these results demonstrate that the microbial contamination constraint has definitely been overcome, and fungal bioremediation technology is ready to be implemented on a larger scale.

Anaerobic membrane bioreactors for pharmaceutical-laden wastewater treatment: A critical review

Pharmaceuticalsare a diverse group of chemical compounds widely used for prevention and treatment of infectious diseases in both humans and animals. Pharmaceuticals, either in their original or metabolite form, find way into the wastewater treatment plants (WWTPs) from different sources. Recently, anaerobic membrane bioreactors (AnMBR) has received significant research attention for the treatment of pharmaceuticals in various wastewater streams. This review critically examines the behaviour and removal of a wide array of pharmaceuticals in AnMBR with primary focus on their removal efficiencies and mechanisms, critical influencing factors, and the microbial community structures. Subsequently, the inhibitory effects of pharmaceuticals on the performance of AnMBR and membrane fouling are critically discussed. Furthermore, the imperative role of membrane biofouling layer and its components in pharmaceuticals removal is highlighted. Finally, recent advancements in AnMBR configurations for membrane fouling control and enhanced pharmaceuticals removal are systemically discussed.

Role of ascomycete and basidiomycete fungi in meeting established and emerging sustainability opportunities: a review

Fungal biomass is the future's feedstock. Non-septate Ascomycetes and septate Basidiomycetes, famously known as mushrooms, are sources of fungal biomass. Fungal biomass, which on averagely comprises about 34% protein and 45% carbohydrate, can be cultivated in bioreactors to produce affordable, safe, nontoxic, and consistent biomass quality. Fungal-based technologies are seen as attractive, safer alternatives, either substituting or complementing the existing standard technology. Water and wastewater treatment, food and feed, green technology, innovative designs in buildings, enzyme technology, potential health benefits, and wealth production are the key sectors that successfully reported high-efficiency performances of fungal applications. This paper reviews the latest technical know-how, methods, and performance of fungal adaptation in those sectors. Excellent performance was reported indicating high potential for fungi utilization, particularly in the sectors, yet to be utilized and improved on the existing fungal-based applications. The expansion of fungal biomass in the industrial-scale application for the sustainability of earth and human well-being is in line with the United Nations' Sustainable Development Goals.

An assessment of hospital wastewater and biomedical waste generation, existing legislations, risk assessment, treatment processes, and scenario during COVID-19

Hospitals release significant quantities of wastewater (HWW) and biomedical waste (BMW), which hosts a wide range of contaminants that can adversely affect the environment if left untreated. The COVID-19 outbreak has further increased hospital waste generation over the past two years. In this context, a thorough literature study was carried out to reveal the negative implications of untreated hospital waste and delineate the proper ways to handle them. Conventional treatment methods can remove only 50%-70% of the emerging contaminants (ECs) present in the HWW. Still, many countries have not implemented suitable treatment methods to treat the HWW in-situ. This review presents an overview of worldwide HWW generation, regulations, and guidelines on HWW management and highlights the various treatment techniques for efficiently removing ECs from HWW. When combined with advanced oxidation processes, biological or physical treatment processes could remove around 90% of ECs. Analgesics were found to be more easily removed than antibiotics, β-blockers, and X-ray contrast media. The different environmental implications of BMW have also been highlighted. Mishandling of BMW can spread infections, deadly diseases, and hazardous waste into the environment. Hence, the different steps associated with collection to final disposal of BMW have been delineated to minimize the associated health risks. The paper circumscribes the multiple aspects of efficient hospital waste management and may be instrumental during the COVID-19 pandemic when the waste generation from all hospitals worldwide has increased significantly.

Advanced bio-oxidation of fungal mixed cultures immobilized on rotating biological contactors for the removal of pharmaceutical micropollutants in a real hospital wastewater

Hospital wastewater represents an important source of pharmaceutical active compounds (PhACs) as contaminants of emerging concern for urban wastewater treatment plants. This work evaluates a fungal biological treatment of a hospital effluent before discharging in the municipal sewer system. This treatment was performed in rotating biological contactors (RBCs) covered with wooden planks in order to promote the attachment of the fungal biomass. These bioreactors, initially inoculated with Trametes versicolor as white rot fungi, have created biofilms of a diversified population of fungal (wood-decaying fungi belonging to Basidiomycota and Ascomycetes) and bacterial (Beta-proteobacteria, Firmicutes, and Acidobacteria) microorganisms. The mixed fungal/bacterial community achieved a stable performance in terms of carbon, nitrogen, and phosphorous reductions for 75 days of continuous operation. Moreover, a remarkable removal of pharmaceutical micropollutants was accomplished especially for antibiotics (98.4 ± 0.7, 83 ± 8% and 76 ± 10 for azithromycin, metronidazole and sulfamethoxazole, respectively). Previous studies have proven a high efficiency of fungi for the removal of microcontaminants as a result of advanced bio-oxidation processes mediated by oxidizing hydroxyl radicals. This study evidences the development of a stable fungal-bacterial mixed culture over wooden-modified RBCs for in-situ removal of pharmaceutical compounds of hospital wastewater under non-sterile conditions and non-strict temperature control, avoiding periodical fungal inoculation due to destabilization and displacement of fungal cultures by indigenous wastewater bacteria.

Laccases—Versatile Enzymes Used to Reduce Environmental Pollution

The accumulation of waste and toxic compounds has become increasingly harmful to the environment and human health. In this context, the use of laccases has become a focus of interest, due to the properties of these versatile enzymes: low substrate specificity, and water formation as a non-toxic end product. Thus, we begin our study with a general overview of the importance of laccase for the environment and industry, starting with the sources of laccases (plant, bacterial and fungal laccases), the structure and mechanism of laccases, microbial biosynthesis, and the immobilization of laccases. Then, we continue with an overview of agro-waste treatment by laccases wherein we observe the importance of laccases for the biodisponibilization of substrates and the biodegradation of agro-industrial byproducts; we then show some aspects regarding the degradation of xenobiotic compounds, dyes, and pharmaceutical products. The objective of this research is to emphasize and fully investigate the effects of laccase action on the decomposition of lignocellulosic materials and on the removal of harmful compounds from soil and water, in order to provide a sustainable solution to reducing environmental pollution.

Sequential fungal pretreatment of unsterilized Miscanthus: changes in composition, cellulose digestibility and microbial communities

A sequential fungal pretreatment of Miscanthus × giganteus was conducted by mixing unsterilized Miscanthus with material previously colonized with the white-rot fungus Ceriporiopsis subvermispora. For three generations, each generation started with inoculation by mixing unsterilized fresh Miscanthus with end material from the previous generation and ended after 28 days of incubation at 28 °C. After the first generation, the cellulose digestibility of the material doubled, compared to that of the unsterilized Miscanthus, but the second and third generations showed no enhancements in cellulose digestibility. Furthermore, high degradation of Miscanthus structural carbohydrates occurred during the first generation. A microbial community study showed that, even though the fungal community of the material previously colonized by C. subvermispora was composed mainly of this fungus (> 99%), by the first generation its relative abundance was down to only 9%, and other microbes had prevailed. Additionally, changes in the bacterial community occurred that might be associated with unwanted cellulose degradation in the system. This reiterates the necessity of feedstock microbial load reduction for the stability and reproducibility of fungal pretreatment of lignocellulosic biomass. KEY POINTS: • Sequential fungal pretreatment of unsterilized Miscanthus was unsuccessful. • Feedstock changes with white-rot fungi favored the growth of other microorganisms. • Feedstock microbial reduction is necessary for pretreatment with C. subvermispora.

Evaluation of an outdoor pilot-scale tubular photobioreactor for removal of selected pesticides from water

This work assesses the capacity of a microalgae-based system to remove three highly to medium polar pesticides typically found in freshwater: acetamiprid, bentazone, and propanil. Degradation of the pesticides was firstly studied individually at batch lab-scale reactors and abiotic and heated-killed controls were employed to clarify their removal pathways. At lab-scale, propanil and acetamiprid were completely removed after 7 days whereas bentazone was not removed. Four and two transformation products (TPs) were generated in the biodegradation process for acetamiprid and propanil, respectively. Then, the simultaneous removal of the pesticides was assessed in an outdoor pilot photobioreactor, operated with a hydraulic residence time of 8 days. During the steady-state, high removal efficiencies were observed for propanil (99%) and acetamiprid (71%). The results from batch experiments suggest that removal is mainly caused by algal-mediated biodegradation. Acetamiprid TPs raised throughout the operational time in the photobioreactor, while no propanil TP was detected at the pilot-scale. This suggests complete mineralization of propanil or residual formation of its TPs at concentrations below the analytical method detection limit. Aiming at biomass valorization, diverse microalgae harvesting methods were investigated for biomass concentration, and the effect of residual pesticides on the biogas yield was determined by biochemical methane potential tests. Anaerobic digestion was not inhibited by the pesticides as verified by the digestion performance. The results highlight the potential of microalgae-based systems to couple nutrient removal, biomass production, micropollutant biodegradation, and biofuel production.

Pesticide bioremediation by Trametes versicolor: Application in a fixed-bed reactor, sorption contribution and bioregeneration

Although immobilization on lignocellulosic materials has recently become a promising strategy in the fungal-based technology for micropollutant bioremediation, research evidence in this area is still scarce and significant knowledge gaps need to be addressed. In this study, Trametes versicolor immobilized on Quercus ilex wood chips was initially proposed to remove two pesticides, diuron and bentazon, from real agricultural wastewater. Thus, a bioremediation treatment was performed in a fixed-bed bioreactor at two empty bed contact times (EBCT) of 1 and 3 days. Bentazon saturation was achieved after 5 EBCTs, while diuron sorption remained below 50% even after 40 days of treatment. The differences in diuron and bentazon removals were linked to their different hydrophobicity and thus, affinity for wood. However, in any case, the sorption contribution of wood was found to be predominant compared to fungal biodegradation. These results motivated a comprehensive study to evaluate the pollutant sorption capacity of wood. Afterwards, pesticide-contaminated wood was successfully bioregenerated by T. versicolor in a biopile-like system, reaching high fungal colonization (up to 0.2451 mg ergosterol·g^-1 dry weight), degradation rate (up to 2.55 mg·g^-1·d^-1) and degradation yields (up to 92.50%). The combined treatment consisting of the fixed-bed bioreactor followed by the re-inoculated biopile showed the best performance in terms of fungal content and pesticide degradation. This is an important step toward the implementation of fungal-based technology for the removal of pesticides from agricultural water.

Degradation of ramipril by residues from the brewing industry: A new carbon-based photocatalyst compound

This study is a pioneer in the use of hydrochar as a support for photocatalytic oxide and its application and evaluation as a catalyst in degradation reactions of ramipril. Novel composites were easily prepared by the support TiO₂ or ZnO nanoparticles on the malt bagasse hydrochar. The preparation of the hydrochar requires low synthesis temperature (250 °C), generating the energy savings of the process. The production of the new composites was well supported by different analytical techniques XRD, FTIR, SSA, SEM, EDS, and reflectance diffuse. The effect of different proportions of TiO₂ or ZnO on the composites was investigated on the degradation efficiency of the pharmaceutical ramipril, without pH adjustment. Composites with a 5:1 hydrochar/TiO₂ or ZnO ratio (MH5T and MH5Z, respectively) showed degradations of 72 and 98% of ramipril at 120 min. This remarkable performance may be associated with the decrease in band gap energy and the electron-hole recombination rate. In addition, the composites were more efficient than metal oxides pristine, and this may be related to the fact that hydrochar have a high concentration of phenolic, hydroxyl, and carboxylic functional groups on their surface. Radical identification tests indicated that h⁺, O₂•^-, and •OH were the reactive species involved in the degradation. The proposed mechanism was studied via LC-MS/MS indicated that the ramipril molecule degrades into low m/z intermediates in the first 60 min of reaction using the MH5Z.

Comparison between two reactors using Trametes versicolor for agricultural wastewater treatment under non-sterile condition in sequencing batch mode

Agricultural wastewater is a major source of herbicides, which pose environmental and health concerns owing to their substantial use and poor elimination rate in conventional wastewater treatment plants. White-rot fungi are versatile in degrading xenobiotics; however, the key problem encountered with their application in actual scenarios is competition with indigenous microorganisms, mainly bacteria. To address this barrier, two different strategies were implemented in the present study. One strategy was to set up a trickle bed with Trametes versicolor immobilized on pine wood, and another strategy was to employ a T. versicolor-pelleted, fluidized-bed reactor to remove diuron and bentazon from actual wastewater under non-sterile conditions. The residence time in the trickle bed was estimated using three methodologies. With 10 batches of a 3-day cycle operation, although the trickle-bed reactor possessed a shorter contact time (8.5 h per cycle) and lower laccase activity compared with those of the fluidized-bed reactor, it demonstrated a higher removal yield and lower bacterial counts. In addition, the utilization of pine wood as a carrier obviously reduced the cost since no additional nutrients were required. Hence, after evaluating all advantages and limitations of both bioreactors, for the purpose of treating over the long term and scaling up, a trickle-bed reactor is the preferred choice.

Removal of Pharmaceuticals from Wastewater: Analysis of the Past and Present Global Research Activities

Water pollution is a worldwide problem. Water consumption increases at a faster rate than population and this leads to a higher pollution rate. Sustainable Development Goals (SDG) include proposals aimed at ensuring the availability of clean water and its sustainable management (Goal 6), as well as the conservation and sustainable use of oceans and seas. The current trend consists in trying to reconcile economic growth with sustainability, avoiding the negative externalities for the environment generated by human activity. More specifically, the objective of this article is to present the evolution of the research regarding the removal of polluting pharmaceuticals that are discharged into wastewater. To do that, a bibliometric analysis of 2938 articles comprising the period 1979–2020 has been carried out. This analysis includes productivity indicators in the scientific field: journals, authors, research institutions and countries. In addition, keyword analysis allows the identification of four main axes of the research regarding the removal of pharmaceutical residues found in wastewater. The first group of articles is aimed at identifying the pharmaceuticals present in polluting effluents. The second and third groups of articles focus on presenting the procedures that enable the treatment of emerging contaminants, either from a biological point of view (second group) or a physicochemical point of view (third group). The fourth group refers to water quality and its possibilities to be reused. Finally, there is a growing trend of worldwide scientific publications, which justifies the importance of polluting residues management, especially those of pharmaceutical origin, in order to achieve a more sustainable society.

A comprehensive insight into the application of white rot fungi and their lignocellulolytic enzymes in the removal of organic pollutants

Environmental problems resultant from organic pollutants are a major current challenge for modern societies. White rot fungi (WRF) are well known for their extensive organic compound degradation abilities. The unique oxidative and extracellular ligninolytic systems of WRF that exhibit low substrate specificity, enable them to display a considerable ability to transform or degrade different environmental contaminants. In recent decades, WRF and their ligninolytic enzymes have been widely applied in the removal of polycyclic aromatic hydrocarbons (PAHs), pharmaceutically active compounds (PhACs), endocrine disruptor compounds (EDCs), pesticides, synthetic dyes, and other environmental pollutants, wherein promising results have been achieved. This review focuses on advances in WRF-based bioremediation of organic pollutants over the last 10 years. We comprehensively document the application of WRF and their lignocellulolytic enzymes for removing organic pollutants. Moreover, potential problems and intriguing observations that are worthy of additional research attention are highlighted. Lastly, we discuss trends in WRF-remediation system development and avenues that should be considered to advance research in the field.

Prospects on coupling UV/H2O2 with activated sludge or a fungal treatment for the removal of pharmaceutically active compounds in real hospital wastewater

Conventional active sludge (AS) process at municipal centralized wastewater treatment facilities may exhibit little pharmaceuticals (PhACs) removal efficiencies when treating hospital wastewater (HWW). Therefore, a dedicated efficient wastewater treatment at the source point is recommended. In this sense, advanced oxidation processes (AOPs) and fungal treatment (FG) have evidenced promising results in degrading PhACs. The coupling of the AOP based on UV/H₂O₂ treatment with biological treatment (AS or FG) treating a real non-sterile HWW, was evaluated in this work. In addition, a coagulation-flocculation pretreatment was applied to improve the efficiency of all approaches. Twenty-two PhACs were detected in raw HWW, which were effectively removed (93-95%) with the combination of any of the biological treatment followed by UV/H₂O₂ treatment. Similar removal results (94%) were obtained when placing UV/H₂O₂ treatment before FG, while a lower removal (83%) was obtained in the combination of UV/H₂O₂ followed by AS. However, the latest was the only treatment combination that achieved a decrease in the toxicity of water. Moreover, deconjugation of conjugated PhACs has been suggested for ofloxacin and lorazepam after AS treatment, and for ketoprofen after fungal treatment. Monitoring of carbamazepine and its transformation products along the treatment allowed to identify the same carbamazepine degradation pathway in UV/H₂O₂ and AS treatments, unlike fungal treatment, which followed another degradation route.

Occurrence, influence and removal strategies of mycotoxins, antibiotics and microplastics in anaerobic digestion treating food waste and co-digestive biosolids: A critical review

Food waste anaerobic digestion (FWAD) can be assisted with the co-digestion of manures, agricultural waste, and sewage sludge. Nevertheless, contaminants like mycotoxins, antibiotics, and microplastics (MPs) could be introduced and negatively affect the AD system. Over 180 literatures involved the occurrence, influence and removal strategies of these three types of pollutants in AD were summarized in this review. Aflatoxin B1(AFB1) as the most concerned mycotoxins were poorly degraded and brought about inhibitions in short-term. Considering methanogenesis inhibition and occurrence concentration, the risk of oxytetracycline and norfloxacin were identified as priority among antibiotics. Leaching toxic additives from MPs could be responsible for the AD inhibition, while their materials and sizes could also prolong the acidification and methanation processes in FWAD. Strategies of bioaugmentation technologies and bioreactors to enhance the removal were suggested. Perspectives were provided for a better understanding of the fates of reviewed contaminants and their elimination in FWAD systems.

Laccase as an efficacious approach to remove anticancer drugs: A study of doxorubicin degradation, kinetic parameters, and toxicity assessment

The degradation of an anticancer drug by laccase was investigated for the first time, bringing a new approach to treat these hazardous substances through the direct enzymatic application. Degradations of doxorubicin by laccase were performed in different enzymatic concentrations, pH values and temperatures through kinetic studies. The highest enzymatic degradation of doxorubicin was achieved at pH 7 and 30 ºC, which resembles effluent characteristics from wastewater treatment plants. Assays were carried out in different doxorubicin concentrations to comprehend the enzymatic kinetics of degradation. Michaelis-Menten kinetic parameters obtained were maximum velocity obtained (V_max) of 702.8 µg_DOX h^-1 L^-1 and Michaelis-Menten constant (K_M) of 4.05 µM, which showed a good affinity for the substrate. The toxicity was evaluated against L-929 cell line, and the degraded doxorubicin solution did not show a reduction in cell viability in the concentration of 250 µg L^-1. In contrast, the doxorubicin shows a reduction of 27% in cell viability. Furthermore, in the highest tested concentration (1000 µg L^-1), enzymatic degradation reduced in up 41.4% the toxicity of doxorubicin, which indicates laccase degrades doxorubicin to non-toxic compounds. In conclusion, this study provides a new application to laccase since the results showed great potential to remove anticancer drugs from effluents.

Non-domestic wastewater treatment with fungal/bacterial consortium followed by Chlorella sp., and thermal conversion of the generated sludge

Liquid waste from biological stains is considered non-domestic wastewater difficult to treat, generating high environmental impact. Therefore, the objective of this work was to carry out secondary and tertiary treatment of these effluents at a pilot scale, using a fungal/bacterial consortium followed by Chorella sp., for 15 days. In addition, to obtain an adsorbent material for Malachite Green dye removal, sludge generated in the plant and pine bark co-pyrolysis was performed. For microalgae isolation and selection of the Chlorophyceae class, Chlorococcales order, and Chorella sp. genus Winogradsky columns were employed. After 15 days of pilot plant treatment, removal percentages of 91 ± 2%, 90 ± 4% and 17 ± 2% were obtained for Colour Units, Chemical Oxygen Demand and Nitrates, respectively. Two types of class II biochar (BC₅₀₀ and BC₇₀₀) and one of class III (BC₃₀₀) were produced. The highest value for Fixed carbon (FC) was obtained at 300 °C (27.3 ± 3%), decreasing as the temperature increased by 25.9 ± 5% and 24.8 ± 2%, for BC₅₀₀ and BC₇₀₀, respectively. Biochar yield was 62.1 ± 3%, 46.3 ± 4% and 31.6 ± 3% for BC₃₀₀, BC₅₀₀ and BC₇₀₀, respectively. Finally, BC₅₀₀ and BC₇₀₀ biochar efficiently adsorbed Malachite Green obtaining qe values of 0.290 ± 0.032, 0.281 ± 0.015, 0.186 ± 0.009 and 0.191 ± 0.012 mg g^-1 at pH values of 4.0 and 8.0 ± 0.2, respectively. Pseudo-second order model demonstrated a chemical adsorption took place, which was influenced by pH.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13205-021-02780-1.

White-rot fungi-mediated biodegradation of cytostatic drugs - bleomycin and vincristine

The contamination of the environment with anticancer drugs, which show recalcitrance to conventional wastewater treatment, has become a significant ecological threat. Fungi represent a promising non-conventional biological alternative for water conditioning. The aim of this work was to evaluate the efficacy of five white-rot fungi (Fomes fomentarius (CB13), Hypholoma fasciculare (CB15), Phyllotopsis nidulans (CB14), Pleurotus ostreatus (BWPH) and Trametes versicolor (CB8)) in the removal of bleomycin and vincristine. The removal capacity was measured at 0, 4, 9, and 14 days of incubation using SPE-UPLC-MS. The enzymatic profiles of laccase, manganese, and lignin peroxidases and wide range of eco- and cytotoxicity, assays of the post-process samples were also conducted. We observed >94% vincristine elimination by F. fomentarius, H. fasciculare and T. versicolor after only 4 days. Bleomycin removal occurred after a minimum of 9 days and only when the drug was incubated with T. versicolor (36%) and H. fasciculare (25%). The removal of both cytostatics was associated with laccase production, and the loss of eco- and cytotoxicity, especially in regard to viability of Lemna minor and Daphnia magna, as well as fibroblasts morphology.

Detailed characterization, antibiotic resistance and seasonal variation of hospital wastewater

This study investigates the presence of the different classes of micro-pollutants such as pharmaceutical active compounds (PhACs) (20 antibiotics, 8 analgesics and anti-inflammatories, 5 cytostatic agents, 7 β-blockers, 4 lipid regulators, 13 psychiatrics, 1 antidiabetic, 1 receptor antagonist, 1 local anaesthetic, 1 antihypertensive and their 5 metabolites), hormones (8 compounds), X-ray contrast agents (6 compounds), benzotriazoles (3 compounds) and pesticides (6 compounds), and antibiotic resistance in hospital wastewater (HWW) of a medical faculty in Istanbul, Turkey. In addition, the seasonal variations of the selected PhACs and X-ray contrast agents and antibiotic resistance were evaluated for 2 years in a total of eight samples. In the PhACs, sulfamethoxazole and its metabolite (4 N-acethyl-sulfamethoxazole) in the antibiotic group and paracetamol in the analgesic and anti-inflammatory group were found at 100% of frequency and the highest concentrations as 35, 43 and 210 μg/L, respectively. The mean concentrations of psychiatric compounds were found less than 0.25 μg/L except carbamazepine (1.36 μg/L). Bisphenol A in hormone group had the highest concentration up to 14 μg/L. In the hormone group compounds, 17-α-Ethinylestradiol and 17-β-Estradiol were detected at lower mean concentrations of 0.2 and 0.05 μg/L, respectively. 1H-benzotriazole had the highest concentration with the mean concentration of 24.8 μg/L in benzotriazole group compounds. The compounds in X-ray contrast agents group were noted as compounds detected at the highest concentration in HWW up to 3000 μg/L. Antibiotic resistance against azithromycin, clindamycin and trimethoprim-sulfamethoxazole antibiotics was observed around 50% in the winter period. The seasonal variation was detected for the most of the investigated PhACs, especially in antibiotic group which was in line with those significant differences in antibiotic resistance rates in the studied antibiotics between winter and summer seasons.

Use of lignocellulosic substrate colonized by oyster mushroom (Pleurotus ostreatus) for removal of organic micropollutants from water

Efficient removal techniques are urgently needed to remove organic micropollutants (OMPs) from wastewater, in order to protect water resources. In this study, laccase activity of mushroom substrate colonized by Pleurotus ostreatus was evaluated as a novel wastewater treatment method for removal of OMPs, including diclofenac, bicalutamide, lamotrigine, and metformin at environmentally relevant concentrations. Laccase activity of the colonized mushroom substrate was found to be highest, 0.8 enzyme activity (U)/g mushroom substrate wet weight, immediately before initiation of fruiting body formation. The selected OMPs were treated for 5 min with suspensions of mushroom substrate with laccase activity of approximately 50 U/L. Removal of all OMPs was significant, with the highest removal for diclofenac of 90% compared with a control with uncolonized mushroom substrate. To our knowledge, direct use of colonized mushroom substrate in removing diclofenac from water has not been reported previously. Removal efficiency of bicalutamide, lamotrigine, and metformin was 43%, 73%, and 59%, respectively. This demonstrates potential for using mushroom substrate colonized by P. ostreatus for removal of OMPs from wastewater.

A sustainability anti-infective pharmaceutical wastewater treatment technology: multi-stage vertical variable diameter membrane bioreactor with DO online controlling

The proper choice of dissolved oxygen (DO) is important in aerobic treatment. In this paper, a multi-stage vertical variable diameter membrane bioreactor was developed to treat pharmaceutical wastewater containing 6-APA and ceftriaxone sodium. In the 180 days of operation, the performance of COD, BOD₅, 6-APA, ceftriaxone sodium removal, sludge index, and microbial enzyme activity under different DOs (from 0.5 to 6.0 mg/L) were investigated. The results showed that the optimal range of DO was 1.5-2.1 mg/L, and the highest removal rates of COD and BOD₅ were observed 87.3%±2.4% and 95.3%±1.8%, the corresponding effluent COD and BOD₅ were 189 mg/L and 24 mg/L, respectively. To reduce the energy consumption and ensure stability of DO in the reactor, a control strategy based on an improved differential evolution BP fuzzy neural network was built and found that the performance and cost of the controlled DO were improved effectively than that of uncontrolled DO.

Trametes versicolor immobilized on rotating biological contactors as alternative biological treatment for the removal of emerging concern micropollutants

White rot fungi have been studied for the removal of micropollutants of emerging concern from wastewater during the last decade. However, several issues need to be overcome for its plausible implementation at full-scale installations such as the addition of supplementary substrates, the partial re-inoculation of fresh fungi or the use of extended hydraulic retention times. This work proposes the immobilization of Trametes versicolor on rotating biological contactors at bench scale (flowrates of 10 L/d and reactor capacity of 10 L) for the treatment of different urban wastewater. This type of bioreactor achieved remarkable reductions of the total organic carbon loading of the wastewater (70-75%) in a wide range of C:N and C:P ratios with limited addition of supplementary substrates, non-refreshment of the fungal biomass and only 1-day of hydraulic retention. The addition of gallic acid as quinone-like mediator and quelated iron and manganese complexes increased the removal of pharmaceutical micropollutants mediated by the so-called advanced bio-oxidation process. The immobilization of Trametes versicolor on rotating biological contactors also showed a remarkable stabilization of the fungi during the continuous treatment of different urban wastewater under non-sterile conditions. Thus, this system is a sound alternative for biological urban wastewater treatment with pharmaceutical removal because overcome all the problems usually associated with the water treatment technologies based on white rot fungi that makes difficult the scaling-up of the process and its implementation in full scale wastewater treatment plants.

Synthesis of Poly(methacrylic acid)/Montmorillonite Hydrogel Nanocomposite for Efficient Adsorption of Amoxicillin and Diclofenac from Aqueous Environment: Kinetic, Isotherm, Reusability, and Thermodynamic Investigations

Herein, a simplistic redox polymerization strategy was utilized for the fabrication of a poly(methacrylic acid)/montmorillonite hydrogel nanocomposite (PMA/nMMT) and probed as a sorbent for sequestration of two pharmaceutical contaminants, viz., amoxicillin (AMX) and diclofenac (DF), from wastewater. The synthesized hydrogel nanocomposite was characterized by the Fourier transform infrared, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy-energy dispersive X-ray spectroscopy, and transmission electron microscopy techniques to analyze structural characteristics and sorption interactions. The efficacy of PMA/nMMT was thoroughly investigated for the sequestration of AMX and DF from the aquatic phase with a variation in operative variables like agitation time, sorbent dosage, pH, and initial sorbate concentration. The reaction kinetics was essentially consistent with the pseudo-second-order model with rate dominated by the intraparticle diffusion model as well as the film diffusion mechanism. The Freundlich isotherm appropriated the equilibrium data over the entire range of concentration. Thermodynamic investigation explored the spontaneous and endothermic nature of the process. The most possible mechanism has been explained, which includes electrostatic interaction, hydrogen bonding, cationic exchange, and partition mechanism. Economic feasibility, better sorption capacity (152.65 for AMX and 152.86 mg/g for DF), and efficient regeneration and reusability even after four consecutive sorption-desorption cycles ascertained PMA/nMMT as a potential sorbent for AMX and DF uptake from the aqueous phase.

Isolation of Fungal Strains from Municipal Wastewater for the Removal of Pharmaceutical Substances

Fungi have been shown to be promising candidates to be used in removal of pharmaceutical compounds during wastewater treatment processes. However, fungal growth, including removal efficiency, can be affected by several factors, such as temperature and the pH. The ability of fungal isolates to grow in the presence of carbamazepine, diclofenac, ibuprofen, and sulfamethoxazole was tested. Removal efficiency results indicated that a fungal isolate of Aspergillus luchuensis can completely (>99.9%) remove diclofenac from a synthetic wastewater media without a pH correction within 10 days of incubation. Furthermore, the results of the biosorption test for A. luchuensis indicate that this isolate uses the biosorption mechanism as a strategy to remove diclofenac. Finally, the results demonstrate that A. luchuensis can remove >98% of diclofenac in non-sterile wastewater without a pH correction immediately after biomass inoculation on biofilm carriers while Trametes versicolor requires an incubation period of at least 24 h to completely remove diclofenac. Therefore, this isolate is a promising candidate for use in removal of pharmaceutical compounds from wastewater with typical pH 7.8, minimizing a requirement of the pH correction.

Performance of wild-Serbian Ganoderma lucidum mycelium in treating synthetic sewage loading using batch bioreactor

The fluctuation of domestic wastewater characteristic inhibits the current conventional microbial-based treatment. The bioremediation fungi has received attention and reported to be an effective alternative to treat industrial wastewater. Similar efficient performance is envisaged for domestic wastewater whereby assessed performance of fungi for varying carbon-to-nitrogen ratios in domestic wastewater is crucial. Thus, the performance of pre-grown wild-Serbian Ganoderma lucidum mycelial pellets (GLMPs) was evaluated on four different synthetic domestic wastewaters under different conditions of initial pH (pH 4, 5, and 7) and chemical oxygen demand (COD) to nitrogen (COD/N) ratio of 3.6:1, 7.1:1, 14.2:1, and 17.8:1 (C3.6N1, C7.1N1, C14.2N1, and C17.8N1). The COD/N ratios with a constant concentration of ammonia-nitrogen (NH₃-N) were chosen on the basis of the urban domestic wastewater characteristics sampled at the inlet basin of a sewage treatment plant (STP). The parameters of pH, COD, and NH₃-N were measured periodically during the experiment. The wild-Serbian GLMPs efficiently removed the pollutants from the synthetic sewage. The COD/N ratio of C17.8N1 wastewater had the best COD and NH₃-N removal, as compared to the lower COD/N ratio, and the shortest treatment time was obtained in an acidic environment at pH 4. The highest percentage for COD and NH₃-N removal achieved was 96.0% and 93.2%, respectively. The results proved that the mycelium of GLMP has high potential in treating domestic wastewater, particularly at high organic content as a naturally sustainable bioremediation system.

Metal Ion-Bridged Forward Osmosis Membranes for Efficient Pharmaceutical Wastewater Reclamation

Membrane performance in separation relies largely on the membrane properties. In this study, metal ions of Cu²⁺, Co²⁺, and Fe³⁺ are used individually as a bridge to develop forward osmosis (FO) membranes via a clean complexation reaction. A metal ion-bridged hydration layer is formed and endows the membrane with a more hydrophilic and smoother surface, higher fouling resistance, and renewability. These improvements make the newly developed membranes superior to the pristine one with better FO performances. The Fe³⁺-bridged membrane produces water fluxes increased up to 133% (FO mode) and 101% (PRO mode) compared with the pristine membrane against DI water with 0.5-2.0 M MgCl₂ as the draw solution. The Fe³⁺-bridged membrane can efficiently reclaim pharmaceuticals such as trimethoprim and sulfamethoxazole from their dilute solutions with good water permeability and a high pharmaceutical retention. This membrane also exhibits a stronger renewability with water flux restored to 98% of its original value after 20 h experiments in trimethoprim-containing water treatment. This study provides a facile and clean approach to develop highly efficient FO membranes for wastewater reclamation and pharmaceutical enrichment.

New insight into effect of antibiotics concentration and process configuration on the removal of antibiotics and relevant antibiotic resistance genes

To compare the performance and antibiotic-resistance character in different process configurations under different levels of antibiotics, anoxic/oxic-membrane bioreactors (MBR) 1#, MBR2# and a sequencing batch reactor (SBR) were operated with identical operating parameters. MBR1# and SBR were operated under high and increasing levels of antibiotics, MBR2# received constant and low concentration of antibiotics. Microbiological community and antibiotic resistance genes (ARGs) were investigated using 16S rDNA gene high-throughput sequencing and qPCR. More than 90% of penicillin and chlortetracycline were removed due to strong hydrolysis, followed by sulfamethoxazole (69.27%-86.25%) through biodegradation and norfloxacin (28.66%-53.86%) through adsorption. Process configuration affected total nitrogen removal more, while antibiotics concentration affected total phosphorus removal more. MBR1# outperformed SBR in reducing sulfamethoxazole, norfloxacin and ARGs due to the retention effect of the membrane module. Retention efficiency of ARGs in MBRs increased along the operation. Compared to the operational taxonomic unit (OTU) number before antibiotics addition, the OTU number in MBR1# and SBR decreased by 23.7% and 28.7%, while that in MBR2# kept relatively stable. Process configuration contributed to higher dissimilarity of microbial community than antibiotics concentration. The research provides an insight into the influence factors of antibiotics-containing wastewater treatment.

Ultrasound-assisted synthesis of thermosensitive nanovesicle for direct trap and release of analgesic drugs in biofluid and sewage

An environmentally friendly thermosensitive nanovesicle-cloud point microextraction technique has been developed with the assistant of ultrasonic waves to determine analgesic drugs with a broad range of polarity in field water and human urine. Based on thin-film hydration, the conformation of nanovesicles formed by a binary mixing system with the nonionic surfactants was evaluated using regular and cryogenic transmission electron microscopy. The multilayered nano-spherical structure was able to capture polar and nonpolar compounds simultaneously. Analgesic drugs (acetaminophen, salicylic acid, ketoprofen, diclofenac, indomethacin, ibuprofen, and mefenamic acid) were detected by ultra-performance liquid chromatography coupled to photodiode array detection. Under optimal conditions including the type and ratio of surfactants, sonication time and sonication temperature, linear calibration curves were obtained over the range of 50-8000 μg L^-1. The coefficient of determination (R²) ranged from 0.9953 to 0.9995, with detection limits of 10-100 μg L^-1. The relative standard deviations ranged from 3.2% to 12.7% for intraday precision (n = 5) and 2.5% to 14.1% for interday precision (n = 15). The relative recoveries obtained from one industrial wastewater sample and two field water samples ranged from 86.1% to 108.1%. In the human urine analysis, three volunteers ingested 1500 mg of acetaminophen. After 4 h, the concentration of acetaminophen in the urine was found to range from 87.0 to 197.9 mg L^-1.

Long-term continuous treatment of non-sterile real hospital wastewater by Trametes versicolor

BACKGROUND

Hospital wastewater is commonly polluted with high loads of pharmaceutically active compounds, which pass through wastewater treatment plants (WWTPs) and end up in water bodies, posing ecological and health risks. White-rot fungal treatments can cope with the elimination of a wide variety of micropollutants while remaining ecologically and economically attractive. Unfortunately, bacterial contamination has impeded so far a successful implementation of fungal treatment for real applications.

RESULTS

This work embodied a 91-day long-term robust continuous fungal operation treating real non-sterile hospital wastewater in an air pulsed fluidized bed bioreactor retaining the biomass. The hydraulic retention time was 3 days and the ageing of the biomass was avoided through partial periodic biomass renovation resulting in a cellular retention time of 21 days. Evolution of microbial community and Trametes abundance were evaluated.

CONCLUSIONS

The operation was able to maintain an average pharmaceutical load removal of over 70% while keeping the white-rot fungus active and predominant through the operation.

Comparative analysis of toxicity reduction of wastewater in twelve industrial park wastewater treatment plants based on battery of toxicity assays

Wastewater treatment plants (WWTPs) in industrial parks provide centralized treatment for industrial and domestic wastewater. However, the information on toxicity reduction of wastewater and its correlation with treatment process in industrial park is limited. This study compared the toxicity reduction of wastewater in 12 industrial park WWTPs based on battery of toxicity assays. Nine toxic endpoints involving microorganism, phytoplankton, zooplankton, plant and human cell lines were applied. All the influents of WWTPs induced high toxicities, which were significantly reduced after the treatments from 7 of the studied WWTPs. However, the effluents of five WWTPs induced higher toxicity in one or more toxic endpoints compared to the influents. This study also found that most of anaerobic-anoxic-oxic (A²/O)-based processes had good removal efficiency of wastewater toxicity, while the sequencing batch reactor (SBR)-based processes had the lowest removal efficiency. Moreover, low correlation coefficients were obtained among all toxic endpoints, indicating that battery of toxicity assays was necessary to completely characterize the toxicity and risk of wastewater in industrial parks. This study shed new lights to the toxicity reduction of wastewater and its correlation with treatment process, which is very useful for the design, management and operation of WWTPs in industrial parks.

Fungal biodegradation of the N-nitrosodimethylamine precursors venlafaxine and O-desmethylvenlafaxine in water

Antidepressant drugs such as Venlafaxine (VFX) and O-desmethylvenlafaxine (ODMVFX) are emerging contaminants that are commonly detected in aquatic environments, since conventional wastewater treatment plants are unable to completely remove them. They can be precursors of hazardous by-products, such as the carcinogenic N-nitrosodimethylamine (NDMA), generated upon water chlorination, as they contain the dimethylamino moiety, necessary for the formation of NDMA. In this study, the capability of three white rot fungi (Trametes versicolor, Ganoderma lucidum and Pleurotus ostreatus) to remove both antidepressants from water and to decrease NDMA formation potential was investigated. Furthermore, transformation by-products (TPs) generated along the treatment process were elucidated and also correlated with their NDMA formation potential. Very promising results were obtained for T. versicolor and G. lucidum, both being able to remove up to 100% of ODMVFX. In the case of VFX, which is very recalcitrant to conventional wastewater treatment, a 70% of removal was achieved by T. versicolor, along with a reduction in NDMA formation potential, thus decreasing the associated problems for human health and the environment. However, the NDMA formation potential remained practically constant during treatment with G. lucidum despite of the equally high VFX removal (70%). This difference was attributed to the generation of different TPs during both fungal treatments. For example, G. lucidum generated more ODMVFX, which actually has a higher NDMA formation potential than the parent compound itself.

Removal of pharmaceutical compounds from urban wastewater by an advanced bio-oxidation process based on fungi Trametes versicolor immobilized in a continuous RBC system

Conventional wastewater treatment plants (WWTPs) are not able to remove completely some emerging contaminants, such as residual pharmaceutical compounds (PCs) with potential ecotoxicity to water bodies. An advanced bio-oxidation process (ABOP) using white-rot fungi (WRF) has been proposed as alternative biological treatment for degradation of non-biodegradable compounds. A synthetic and real wastewater spiked with 12 PCs at 50 μg L^-1 was treated by means of ABOP based on WRF in a rotating biological contactor (RBC) at 1 day of hydraulic retention time (HRT). The ABOP achieved a remarkable biological performance in terms of TOC removal and reduction of N-NH₄ ⁺ and P-PO₄ ^3- nutrients. Likewise, 5 of the 12 PCs were eliminated with removal efficiencies ranging from 80 to 95%, whereas 6 of 12 PCs were eliminated with removal values ranging from 50 to 70%. The anaerobic digestion of the fungal sludge generated upon the treatment was also evaluated, obtaining a methane yield of 250 mL CH₄ g_VS ^-1. These results evidenced that the proposed ABOP is a promising alternative for the sustainable wastewater treatment of urban effluents, combining advanced oxidation with biological operation for the removal of emerging PCs and energy recovery.

Enhancement of H2O2 Decomposition by the Co-catalytic Effect of WS2 on the Fenton Reaction for the Synchronous Reduction of Cr(VI) and Remediation of Phenol

The greatest problem in the Fe(II)/H₂O₂ Fenton reaction is the low production of ·OH owing to the inefficient Fe(III)/Fe(II) cycle and the low decomposition efficiency of H₂O₂ (<30%). Herein, we report a new discovery regarding the significant co-catalytic effect of WS₂ on the decomposition of H₂O₂ in a photoassisted Fe(II)/H₂O₂ Fenton system. With the help of WS₂ co-catalytic effect, the H₂O₂ decomposition efficiency can be increased from 22.9% to 60.1%, such that minimal concentrations of H₂O₂ (0.4 mmol/L) and Fe²⁺ (0.14 mmol/L) are necessary for the standard Fenton reaction. Interestingly, the co-catalytic Fenton strategy can be applied to the simultaneous oxidation of phenol (10 mg/L) and reduction of Cr(VI) (40 mg/L), and the corresponding degradation and reduction rates can reach up to 80.9% and 90.9%, respectively, which are much higher than the conventional Fenton reaction (52.0% and 31.0%). We found that the expose reductive W⁴⁺ active sites on the surface of WS₂ can greatly accelerate the rate-limiting step of Fe³⁺/Fe²⁺ conversion, which plays the key role in the decomposition of H₂O₂ and the reduction of Cr(VI). Our discovery represents a breakthrough in the field of inorganic catalyzing AOPs and greatly advances the practical utility of this method for environmental applications.