Occurrence and fate of emerging wastewater contaminants in Western Balkan Region

Dual dye-labeled aptamers for detection of dichlorvos using ratiometric fluorescence resonance energy transfer

BACKGROUND

Dichlorvos (DDVP) is an efficient and highly toxic organophosphorus pesticide. Considering its effects on human health and ecosystems, pesticide residue and pollution monitoring is of great significance. Traditional methods like chromatography with mass spectrometry are not portable or rapid because they use large instruments and complex pre-processing methods. Compared with other optional on-site detection technologies, like enzymatic and antibody methods, aptamers are advantageous because they are stable, readily modified, and inexpensive. Therefore, screening and developing a specific adapter for DDVP detection is necessary and will be of practical value.

RESULTS

We screened, modified, and compared two dual-labeled aptamer probes (Cy3-DV55-Cy5 and Cy3-DV65-Cy5). The kinetics studied showed that 5 min was sufficient for the detection reaction. Both aptamers showed selectivity for DDVP but DV55 was superior to DV65. To research the binding stabilities and the mechanism between the aptamers and DDVP, the secondary structures, melting temperatures, fluorescence quenching types, and constants were investigated. Which showed that DV55 was specific for DDVP and showed better binding than DV65. Comparison of the UV absorption and FRET for DV55 and the truncated structures suggested that loop 3 in DV55 might play an important role in the binding of DV55 to DDVP. The Cy3-DV55-Cy5 aptamer had a linear range of 0-100 μM for DDVP detection and the limit of detection was 150 nM. Simulated pesticide residue detection experiments showed that the method was simple, fast, and had acceptable recovery (89.8%-105.2 %).

SIGNIFICANCE

Pesticide detection is important but on-site detection methods are usually not portable or rapid. We developed two dual-labeled aptamer probes that could feasibly be practically applied to rapid on-site DDVP detection of pesticide residues and pollutants. This research provides experimental and theoretical data for the development and design of similar pesticide probes.

Occurrence of micropollutants in rural domestic wastewater in Zhejiang Province, China and corresponding wastewater-based epidemiology analysis

By 2021, rural regions in China were occupied by over 500 million residents, generating an annual volume of 19.5 billion m3 of rural domestic wastewater (RDW). This study aimed to investigate the occurrence and removal of micropollutants (MPs) in RDW treatment facilities and to perform a corresponding wastewater-based epidemiology analysis (WBE). Our findings indicated the significantly high levels of influent MPs, particularly pharmaceuticals, such as ofloxacin and diclofenac being most prevalent (ranging from several to tens of μg/L) across different facilities. After various treatments, regular water indexes in the effluent, like NH3 -N and COD, have basically satisfied the local discharge standard. However, the concentration of certain dominant MPs in effluent remained notably high, ranging from hundreds of ng/L to several μg/L. The risk quotients of MPs like diclofenac, ciprofloxacin, ofloxacin, sulfamethoxazole, diuron, and isoproturon were all above 1 in the effluent, signifying significant hazards to aquatic organisms. The quantitative meta-analysis revealed higher average standardized removal efficiency for membrane bioreactor (MBR) treatment (-11 %) compared to anaerobic/anoxic/aerobic (A2O) treatment (11 %), indicating the higher efficiency of MBR treatment in outperforming the A2O as a secondary treatment. Additionally, employing biofilter as a tertiary treatment proved to be more effective as compared to flocculation-air flotation and artificial wetlands. Moreover, the results of WBE analysis showed that diclofenac and ofloxacin emerged as the most commonly used pharmaceuticals (of seven), with consumption levels recorded at 1222 and 517 mg/(d·103 capita), with daily defined doses per day per 103 capita of 12.2/1000 and 1.29/1000, respectively. This study addresses the existing knowledge gaps regarding the occurrence and removal of MPs in RDW and offers valuable insights into pharmaceutical consumption patterns in rural regions, thereby improving our understanding of public health.

A systematic review of antibiotics and antibiotic resistance genes (ARGs) in mariculture wastewater: Antibiotics removal by microalgal-bacterial symbiotic system (MBSS), ARGs characterization on the metagenomic

Antibiotic residues in mariculture wastewater seriously affect the aquatic environment. Antibiotic Resistance Genes (ARGs) produced under antibiotic stress flow through the environment and eventually enter the human body, seriously affecting human health. Microalgal-bacterial symbiotic system (MBSS) can remove antibiotics from mariculture and reduce the flow of ARGs into the environment. This review encapsulates the present scenario of mariculture wastewater, the removal mechanism of MBSS for antibiotics, and the biomolecular information under metagenomic assay. When confronted with antibiotics, there was a notable augmentation in the extracellular polymeric substances (EPS) content within MBSS, along with a concurrent elevation in the proportion of protein (PN) constituents within the EPS, which limits the entry of antibiotics into the cellular interior. Quorum sensing stimulates the microorganisms to produce biological responses (DNA synthesis - for adhesion) through signaling. Oxidative stress promotes gene expression (coupling, conjugation) to enhance horizontal gene transfer (HGT) in MBSS. The microbial community under metagenomic detection is dominated by aerobic bacteria in the bacterial-microalgal system. Compared to aerobic bacteria, anaerobic bacteria had the significant advantage of decreasing the distribution of ARGs. Overall, MBSS exhibits remarkable efficacy in mitigating the challenges posed by antibiotics and resistant genes from mariculture wastewater.

Addressing the challenges of combined sewer overflows

Europe's ageing wastewater system often combines domestic sewage with surface runoff and industrial wastewaters. To reduce the associated risk of overloading wastewater treatment works during storms, and to prevent wastewater backing-up into properties, Combined Sewer Overflows (CSOs) are designed into wastewater networks to release excess discharge into rivers or coastal waters without treatment. In view of growing regulatory scrutiny and increasing public concern about their excessive discharge frequencies and potential impacts on environments and people, there is a need to better understand these impacts to allow prioritisation of cost-effective solutions.We review: i) the chemical, physical and biological composition of CSOs discharges; ii) spatio-temporal variations in the quantity, quality and load of overflows spilling into receiving waters; iii) the potential impacts on people, ecosystems and economies. Despite investigations illustrating the discharge frequency of CSOs, data on spill composition and loading of pollutants are too few to reach representative conclusions, particularly for emerging contaminants. Studies appraising impacts are also scarce, especially in contexts where there are multiple stressors affecting receiving waters. Given the costs of addressing CSOs problems, but also the likely long-term gains (e.g. economic stimulation as well as improvements to biodiversity, ecosystem services, public health and wellbeing), we highlight here the need to bolster these evidence gaps. We also advocate no-regrets options to alleviate CSO problems taking into consideration economic costs, carbon neutrality, ecosystem benefit and community well-being. Besides pragmatic, risk-based investment by utilities and local authorities to modernise wastewater systems, these include i) more systemic thinking, linking policy makers, consumers, utilities and regulators, to shift from local CSO issues to integrated catchment solutions with the aim of reducing contributions to wastewater from surface drainage and water consumption; ii) broader societal responsibilities for CSOs, for example through improved regulation, behavioural changes in water consumption and disposal of waste into wastewater networks, and iii) greater cost-sharing of wastewater use.

Glacier foreland insect uptake synthetic compounds: an emerging environmental concern

Pesticides, synthetic fragrances and polycyclic aromatic hydrocarbons contaminated two glacier-fed streams (Amola, Mandrone) and one spring (Grostè) in the Italian Alps. Ten compounds (chlorpyrifos (CPY), chlorpyrifos-methyl (CPY-m), galaxolide (HHCB), tonalide (AHTN), fluorene (Flu), phenanthrene (Phen), anthracene (Ant), fluoranthene (Fl), pyrene (Pyr), benzo[a]anthracene (BaA)) accumulated in aquatic larvae of chironomids (Diamesa steinboecki, D. latitarsis, D. bertrami, D. tonsa, D. zernyi, Pseudokiefferiella parva, Orthocladiinae) and tipulids. Their tissue concentrations (detected by gas chromatography coupled with mass spectrometry) ranged from 1.1 ± 0.1 ng/g d.w. (= dry weight) (CPY-m in D. tonsa from Amola) to 68.0 ± 9.1 ng/g d.w. (Pyr in D. steinboecki from Mandrone). HHCB, AHTN, and CPY, with one exception, were accumulated by all aquatic insects. Six compounds (CPY, CPY-m, HHCB, AHTN, Fl, Pyr) also contaminated carabids (Nebria germarii, N. castanea, N. jockischii) predating adults of merolimnic insects. Their tissue concentrations ranged from 1.1 ± 0.3 ng/g d.w. (CPY-m in N. germarii from Mandrone) to 84.6 ± 0.3 ng/g d.w. (HHCB in N. castanea from Grostè). HHCB and AHTN were accumulated by all Nebria species. Intersite and interspecies differences were observed, which might be attributed to different environmental contamination levels. There was a stronger similarity between species from the same site than among the same species from different sites, suggesting that uptake is not species specific. At all sites, the concentration of xenobiotics was higher in larvae than in water and comparable or higher in carabids than in larvae from the same site, suggesting trophic transfer by emerging aquatic insects to their riparian predators.

Review of Endocrine Disrupting Compounds (EDCs) in China's water environments: Implications for environmental fate, transport and health risks

Endocrine Disrupting Compounds (EDCs) are ubiquitous in soil and water system and have become a great issue of environmental and public health concern since the 1990s. However, the occurrence and mechanism(s) of EDCs' migration and transformation at the watershed scale are poorly understood. A review of EDCs pollution in China's major watersheds (and comparison to other countries) has been carried out to better assess these issues and associated ecological risks, compiling a large amount of data. Comparing the distribution characteristics of EDCs in water environments around the world and analyzing various measures and systems for managing EDCs internationally, the significant insights of the review are: 1) There are significant spatial differences and concentration variations of EDCs in surface water and groundwater in China, yet all regions present non-negligible ecological risks. 2) The hyporheic zone, as a transitional zone of surface water and groundwater interaction, can effectively adsorb and degrade EDCs and prevent the migration of high concentrations of EDCs from surface water to groundwater. This suggests that more attention needs to be paid to the role played by critical zones in water environments, when considering the removal of EDCs in water environments. 3) In China, there is a lack of comprehensive and effective regulations to limit and reduce EDCs generated during human activities and their discharge into the water environment. 4) To prevent the deterioration of surface water and groundwater quality, the monitoring and management of EDCs in water environments should be strengthened in China. This review provides a thorough survey of scientifically valid data and recommendations for the development of policies for the management of EDCs in China's water environment.

Predicting micropollutant fate during wastewater treatment using refined classical kinetic model based on quantitative monitoring in multi-metropolitan regions of South Korea

This study aimed to implement an extensive prediction model for the fate of micropollutants (MPs) in wastewater treatment plants (WWTPs). Five WWTPs equipped with seven different biological treatment processes were monitored from 2020 to 2022 with three to four sampling events in each year, and 27 datasets for 20 MPs were collected. Among these datasets, 12 were used to investigate the behavior and fate of MPs in WWTPs in South Korea. Metformin, acetaminophen, caffeine, naproxen, and ibuprofen were the MPs with the highest influent concentrations (ranging from 3,933.3-187,637.0 ng L-1) at all WWTPs. More than 90% of MPs were removed by biological treatment processes in all WWTPs. The Kruskal-Wallis test verified that their efficacy did not differ statistically (p-value > 0.05). Meanwhile, to refine the performance of the prediction model, this study optimized the biodegradation rate constants (kbio) of each MP according to the variation of seasonal water temperature. As a result, compared to the original prediction model, the mean difference between the actual data and predicted results (MEAN) decreased by 6.77%, while the Nash-Sutcliffe efficiency (NSE) increased by 0.226. The final MEAN and NSE for the refined prediction model were calculated to be 5.09% and 0.964, respectively. The prediction model made accurate predictions, even for MPs exhibiting behaviors different from other cases, such as estriol and atrazine. Consequently, the optimization strategy proposed in this study was determined to be effective because the overall removal efficiencies of MPs were successfully predicted even with limited reference datasets.

Occurrence, environmental impact and fate of pharmaceuticals in groundwater and surface water: a critical review

In many nations and locations, groundwater serves as the population's primary drinking water supply. However, pharmaceuticals found in groundwater and surface waters may affect aquatic ecosystems and public health. As a result, their existence in natural raw waters are now more widely acknowledged as a concern. This review summarises the evidence of research on pharmaceuticals' occurrence, impact and fate, considering results from different water bodies. Also, various analytical techniques were reviewed to compare different pharmaceuticals' detection frequencies in water bodies. These include liquid chromatography-mass spectrometry (LC-MS), high-performance liquid chromatography (HPLC), ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), and gas chromatography-mass spectrometry (GC-MS). However, owing to LC-MS's high sensitivity and specification, it is the most reported instrument used for analysis. The PRISMA reviewing methodology was adopted based on relevant literature in order to focus on aim of the review. Among other pharmaceuticals reviewed, sulfamethoxazole was found to be the most frequently detected drug in wastewater (up to 100% detection frequency). The most reported pharmaceutical group in this review is antibiotics, with sulfamethoxazole having the highest concentration among the analysed pharmaceuticals in groundwater and freshwater (up to 5600 ng/L). Despite extensive study and analysis on the occurrence and fate of pharmaceuticals in the environment, appropriate wastewater management and disposal of pharmaceuticals in the water environment are not still monitored regularly. Therefore, there is a need for mainstream studies tailored to the surveillance of pharmaceuticals in water bodies to limit environmental risks to human and aquatic habitats in both mid and low-income nations.

The Synthesis and Evaluation of Porous Carbon Material from Corozo Fruit (Bactris guineensis) for Efficient Propranolol Hydrochloride Adsorption

This study explores the potential of the corozo fruit (Bactris guineensis) palm tree in the Colombian Caribbean as a source for porous carbon material. Its specific surface area, pore volume, and average pore size were obtained using N₂ adsorption/desorption isotherms. The images of the precursor and adsorbent surface were obtained using scanning electron microscopy (SEM). Fourier transform infrared (FTIR) spectra were obtained to detect the main functional groups present and an X-ray diffraction analysis (XRD) was performed in order to analyze the structural organization of the materials. By carbonizing the fruit stone with zinc chloride, a porous carbon material was achieved with a substantial specific surface area (1125 m² g⁻¹) and pore volume (3.241 × 10-¹ cm³ g⁻¹). The material was tested for its adsorption capabilities of the drug propranolol. The optimal adsorption occurred under basic conditions and at a dosage of 0.7 g L⁻¹. The Langmuir homogeneous surface model effectively described the equilibrium data and, as the temperature increased, the adsorption capacity improved, reaching a maximum of 134.7 mg g⁻¹ at 328.15 K. The model constant was favorable to the temperature increase, increasing from 1.556 × 10^-1 to 2.299 × 10^-1 L mg^-1. Thermodynamically, the adsorption of propranolol was found to be spontaneous and benefited from higher temperatures, indicating an endothermic nature (12.39 kJ mol⁻¹). The negative ΔG⁰ values decreased from -26.28 to -29.99 kJ mol^-1, with the more negative value occurring at 328 K. The adsorbent material exhibited rapid kinetics, with equilibrium times ranging from 30 to 120 min, depending on the initial concentration. The kinetics data were well-represented by the general order and linear driving force models. The rate constant of the general order model diminished from 1.124 × 10^-3 to 9.458 × 10^-14 with an increasing concentration. In summary, the leftover stone from the Bactris guineensis plant can be utilized to develop activated carbon, particularly when activated using zinc chloride. This material shows promise for efficiently adsorbing propranolol and potentially other emerging pollutants.

Antimicrobial Transformation Products in the Aquatic Environment: Global Occurrence, Ecotoxicological Risks, and Potential of Antibiotic Resistance

The global spread of antimicrobial resistance (AMR) is concerning for the health of humans, animals, and the environment in a One Health perspective. Assessments of AMR and associated environmental hazards mostly focus on antimicrobial parent compounds, while largely overlooking their transformation products (TPs). This review lists antimicrobial TPs identified in surface water environments and examines their potential for AMR promotion, ecological risk, as well as human health and environmental hazards using in silico models. Our review also summarizes the key transformation compartments of TPs, related pathways for TPs reaching surface waters and methodologies for studying the fate of TPs. The 56 antimicrobial TPs covered by the review were prioritized via scoring and ranking of various risk and hazard parameters. Most data on occurrences to date have been reported in Europe, while little is known about antibiotic TPs in Africa, Central and South America, Asia, and Oceania. Occurrence data on antiviral TPs and other antibacterial TPs are even scarcer. We propose evaluation of structural similarity between parent compounds and TPs for TP risk assessment. We predicted a risk of AMR for 13 TPs, especially TPs of tetracyclines and macrolides. We estimated the ecotoxicological effect concentrations of TPs from the experimental effect data of the parent chemical for bacteria, algae and water fleas, scaled by potency differences predicted by quantitative structure-activity relationships (QSARs) for baseline toxicity and a scaling factor for structural similarity. Inclusion of TPs in mixtures with their parent increased the ecological risk quotient over the threshold of one for 7 of the 24 antimicrobials included in this analysis, while only one parent had a risk quotient above one. Thirteen TPs, from which 6 were macrolide TPs, posed a risk to at least one of the three tested species. There were 12/21 TPs identified that are likely to exhibit a similar or higher level of mutagenicity/carcinogenicity, respectively, than their parent compound, with tetracycline TPs often showing increased mutagenicity. Most TPs with increased carcinogenicity belonged to sulfonamides. Most of the TPs were predicted to be mobile but not bioaccumulative, and 14 were predicted to be persistent. The six highest-priority TPs originated from the tetracycline antibiotic family and antivirals. This review, and in particular our ranking of antimicrobial TPs of concern, can support authorities in planning related intervention strategies and source mitigation of antimicrobials toward a sustainable future.

Molecular dynamics simulations on interactions of five antibiotics with luciferase of Vibrio Qinghaiensis sp.-Q67

A large number of antibiotics have been used in the medical industry, agriculture, and animal husbandry industry in recent years. It may cause pollution to the aquatic environment and ultimately threaten to human health due to their prolonged exposure to the environment. We aim to study the toxicity mechanism of enrofloxacin (ENR), chlortetracycline hydrochloride (CTC), trimethoprim (TMP), chloramphenicol (CMP), and erythromycin (ETM) to luciferase of Vibrio Qinghaiensis sp.-Q67 (Q67) by using toxicity testing combined with molecular docking, molecular dynamics, and binding free energy analysis. The curve categories for ENR were different from the other four antibiotics, with ENR being J-type and the rest being S-type, and the toxicity of these five antibiotics (pEC50) followed the order of ENR (7.281) > ETM (6.814) > CMP (6.672) > CTC (6.400) > TMP (6.123), the order of toxicity value is consistent with the the magnitude of the binding free energy (ENR (-47.759 kcal/mol), ETM (-46.821 kcal/mol), CMP (-42.905 kcal/mol), CTC (-40.946 kcal/mol), TMP (-28.251 kcal/mol)). The van der Waals force provided the most important contribution to the binding free energy of the five antibiotics in the binding system with Q67 luciferase. Therefore, the dominant factor for the binding of antibiotics to luciferase was shape compensation. The face-to-face π-π stacking interaction between the diazohexane structure outside the active pocket region and the indoles structure of Phe194 and Phe250 in the molecular structure was the main reason for the highest toxicity value of antibiotic ENR. The hormesis effect of ENR has a competitive binding relationship with the α and β subunits of luciferase. Homology modeling, molecular docking, molecular dynamics simulations and binding free energy calculations were used to derive the toxicity magnitude of different antibiotics against Q67, and insights at the molecular level. The conclusion of toxicological experiments verified the correctness of the simulation results. This study contributes to the understanding of toxicity mechanisms of five antibiotics and facilitates risk assessment of antibiotic contaminants in the aquatic environment.

Assessing the Persistence and Mobility of Organic Substances to Protect Freshwater Resources

Persistent and mobile organic substances are those with the highest propensity to be widely distributed in groundwater and thereby, when emitted at low-levels, to contaminate drinking water extraction points and freshwater environments. To prevent such contamination, the European Commission is in the process of introducing new hazard classes for persistent, mobile, and toxic (PMT) and very persistent and very mobile (vPvM) substances within its key chemical regulations CLP and REACH. The assessment of persistence in these regulations will likely be based on simulated half-life, t _1/2, thresholds; the assessment of mobility will likely be based on organic carbon-water distribution coefficient, K _OC, thresholds. This study reviews the use of t _1/2 and K _OC to describe persistence and mobility, considering the theory, history, suitability, data limitations, estimation methods, and alternative parameters. For this purpose, t _1/2, K _OC, and alternative parameters were compiled for substances registered under REACH, known transformation products, and substances detected in wastewater treatment plant effluent, surface water, bank filtrate, groundwater, raw water, and drinking water. Experimental t _1/2 values were rare and only available for 2.2% of the 14 203 unique chemicals identified. K _OC data were only available for a fifth of the substances. Therefore, the usage of alternative screening parameters was investigated to predict t _1/2 and K _OC values, to assist weight-of-evidence based PMT/vPvM hazard assessments. Even when considering screening parameters, for 41% of substances, PMT/vPvM assessments could not be made due to data gaps; for 23% of substances, PMT/vPvM assessments were ambiguous. Further effort is needed to close these substantial data gaps. However, when data is available, the use of t _1/2 and K _OC is considered fit-for-purpose for defining PMT/vPvM thresholds. Using currently discussed threshold values, between 1.9 and 2.6% of REACH registered substances were identified as PMT/vPvM. Among the REACH registered substances detected in drinking water sources, 24-30% were PMT/vPvM substances.

Application of biowaste generated by the production chain of pitaya fruit (Hylocereus undatus) as an efficient adsorbent for removal of naproxen in water

Pharmaceutical compounds are a serious problem in the environment. They cause damage to the aquatic, animal, and human organisms and soon became considered emerging pollutants where their removal is extremely urgent. Among the techniques used, adsorption has been used with success, where several adsorbent materials, including those from residual biomass, have been used to remove these pollutants. In this study, the skins of the pitaya fruit (Hylocereus undatus) productive chain were carbonized with ZnCl₂ to obtain activated carbon and later used in the adsorption of the drug naproxen (NPX) in a batch system. The Freundlich model demonstrated a better adjustment for the equilibrium isotherms. A high adsorption capacity for NPX (158.81 mg g^-1) was obtained at 328 K, which can be attributed to the remarkable textural properties of the adsorbent, besides certain functional groups present on its surface. Thermodynamic studies confirmed the endothermic nature of the adsorption process (∆H⁰ = 0.2898 kJ mol^-1). The linear driving force model (LDF) presented a good statistical adjustment to the experimental kinetic data. The application of the material in the treatment of simulated wastewater composed of various pharmaceutical drugs and salts was very promising, reaching 75.7% removal. Therefore, it can be inferred that the application of activated carbon derived from pitaya bark is highly promising in removing the NPX drug and treating synthetic mixtures containing other pharmaceutical substances.

Prediction of reaction mechanism for OH radical-mediated phenol oxidation using quantum chemical calculation

Understanding the reaction mechanism of OH•-mediated oxidation of organic micropollutants (OMPs) contributes to the assessment and development of advanced oxidation processes (AOPs) for removal of OMPs in water environment. In this study, a theoretical approach using quantum chemical calculation (QCC) was employed to investigate the prediction accuracy of the reaction mechanism (i.e., reaction site and rate) for OH•-mediated oxidation of phenol, where the hydroquinone and catechol are generated as transformation products (TPs) via radical and electrophilic reactions. We compared three different levels of theory (Hartree-Fock, B3LYP, and M06-2X) with 6-311 + G (2d,2p)/SMD, and the reaction site and rate constants were predicted by the Fukui function and transition state theory, respectively. Overall, the prediction accuracy of the TPs formation mechanism was the highest in the calculations using M06-2X. For example, the initial OH• addition to phenol was predicted to occur with a probability of 77% for the ortho position and 23% for the para position, which was consistent with the experimental observation. By applying the transition state theory, the rate constants toward TPs formation pathway can be reasonably reproduced, suggesting that M06-2X has an effective function for polycyclic reactions. However, the observed discrepancies in rate constants are inferred from dispersion effects and the multi-reference property in the computational system or derived from mismatch of target reactions between theoretical calculations and experiments. Overall, this study provides an insight into QCC application for investigating the formation mechanism of TPs in AOPs for removal of OMPs in water environment.

A comprehensive review of 1,2,4-triazole fungicide toxicity in zebrafish (Danio rerio): A mitochondrial and metabolic perspective

In this critical review, we synthesize data from peer-reviewed literature reporting on triazole fungicide exposures in the zebrafish model. Based on their mode of action in plants (potent inhibitors of ergosterol synthesis), we focused attention on mechanisms related to cellular, lipid, and steroid metabolism. Evidence from several studies reveals that zebrafish exposed to triazoles present with impaired mitochondrial oxidative phosphorylation and oxidative stress, as well as dysregulation of lipid metabolism. Such metabolic disruptions are expected to underscore developmental delays, deformity, and aberrant locomotor activity and behaviors often observed following exposure. We begin by summarizing physiological and behavioral effects observed with triazole fungicide exposure in zebrafish. We then discuss mechanisms that may underlie adverse apical effects, focusing on mitochondrial bioenergetics and metabolism. Using computational approaches, we also identify novel biomarkers of triazole fungicide exposure. Extracting and analyzing data contained in the Comparative Toxicogenomics Database (CTD) revealed that transcriptional signatures responsive to different triazoles are related to metabolism of lipids and lipoproteins, biological oxidations, and fatty acid, triacylglycerol, and ketone body metabolism among other processes. Pathway and sub-network analysis identified several transcripts that are responsive in organisms exposed to triazole fungicides, several of which include lipid-related genes. Knowledge gaps and recommendations for future investigations include; (1) targeted metabolomics for metabolites in glycolysis, Krebs cycle, and the electron transport chain; (2) additional studies conducted at environmentally relevant concentrations to characterize the potential for endocrine disruption, given that studies point to altered cholesterol (precursor for steroid hormones), as well as altered estrogen receptor alpha and thyroid hormone expression; (3) studies into the potential role for lipid peroxidation and oxidation of lipid biomolecules as a mechanism of triazole-induced toxicity, given the strong evidence for oxidative damage in zebrafish following exposure to triazole fungicides.

Bioinspired engineering protein nanofibrils-based multilayered self-cleaning membranes for universal water purification

Proteinaceous materials are promising for membranes due to greater mechanical strength, in-built functionalities, amphiphilicity and high molecular loading capacity. Herein, a novel strategy of functionalization of silk nanofibrils with metal oxyhydroxide and fabrication of ultrafast permeable multi-layered and self-cleaning membrane was demonstrated. Typically, 1.9 µm thick multilayered membrane efficiently purifies macromolecules, dyes, pharmaceutical, surfactants and oil-water emulsion contaminated wastewater with rejection rate > 89% with the flux rate > 883 Lm²h^-1. Further, the potential of the multilayered membrane was tested for series of different feed concentrations of fluoride and As (V) to validate the commercial applicability of the multilayered membranes for industry wastewater. Notably, even at higher concentration of 10-30 mgL^-1, >96% for fluoride and >87% for As (V) rejection was obtained. Furthermore, the functionalized multilayered membrane exhibited outstanding performance for fluoride removal in real water streams, where, it purifies approximately 4710 L.m^-2 in two consecutive cycles, before the quality of the effluents no longer meets WHO criteria. However, the remarkable separation efficiency principally attributed to adsorption sites on the surface of the membrane. Thus, various regeneration strategies were established based on the nature of pollutants. More importantly, photocatalytic Fenton-like reaction assisted self-cleaning property of the multilayered membrane is demonstrated for regeneration of organic fouled membrane. Overall, the present multilayered membrane exhibits superior performance in purifying organic, inorganic contaminated water and oil-water emulsion with excellent recyclability; hence, envisaged its application for Universal water purification.

Microalgal-based removal of contaminants of emerging concern

The presence of contaminants of emerging concern (CECs) in the environment has been recognized as a worldwide concern. In particular, water pollution by CECs is becoming a major global problem, which requires ongoing evaluation of water resources policies at all levels and the use of effective and innovative wastewaters treatment processes for their removal. Microalgae have been increasingly recognized as relevant for wastewater polishing, including CECs removal. These microorganisms are commonly cultivated in suspension. However, the use of planktonic microalgae for wastewater treatment has limitations in terms of microbiological contamination, process effectiveness and sustainability. The use of consortia of microalgae and bacteria represents a significant advance for sustainable wastewater polishing, particularly when the microorganisms are associated as biofilms. These immobilized mixed cultures can overcome the limitations of suspended-microalgae systems and improve the performance of the involved species for CECs removal. In addition, microalgae-bacteria based systems can offer a relevant combined effect for CECs removal and biomass production enhancement. This study reviews the advantages and advances on the use of microalgae for wastewater treatment, highlighting the potential on the use of microalgae-bacteria biofilms for CECs removal and the further biomass valorisation for third-generation biofuel production.

Fate of household and personal care chemicals in typical urban wastewater treatment plants indicate different seasonal patterns and removal mechanisms

Studies on the presence and fate of household and personal care chemicals (HPCCs) in wastewater treatment plants (WWTPs) are important due to their increasing consumption worldwide. The seasonal patterns and removal mechanisms of HPCCs are not well understood for WWTPs that apply different treatment technologies. To answer these questions, the sewage and sludge samples were taken from 10 typical WWTPs in Northeast China. Levels of UV filters in the influents in the warm season were significantly greater than that of the cold season (p < 0.05). Significant seasonal differences were found for the removals of many HPCCs. Results revealed that the highest removal efficiencies were found for linear alkylbenzene sulphonates with values ranging from 97.2% to 99.7%, and the values were 50.0%-99.9% for other HPCCs. The SimpleTreat model demonstrated that the studied WWTPs were operating with high efficiency at the time of sampling. The sorption of HPCCs to sludge can be strongly associated with their physicochemical parameters. Mass balance calculation suggested that sorption was the dominant mechanism for the removal of antimicrobials, while degradation and/or biotransformation were the other mechanisms for removing the most HPCCs in the WWTPs. This study real the factors influencing the seasonal patterns and removal mechanisms which imply the need for further studies to fully understands the plant and human health implications as sludge could be used in the municipal land application of biosolids.

Application of Surfactant Modified Natural Zeolites for the Removal of Salicylic Acid-A Contaminant of Emerging Concern

This work aimed to test composites (surfactant modified zeolites prepared by treatment of natural zeolites—clinoptilolite (IZ CLI) and/or phillipsite (PHIL75)-rich tuffs with two different amounts of cationic surfactants: cetylpyridinium chloride (CPyCl) and Arquad^® 2HT-75 (ARQ)) for the adsorption of salicylic acid (SA)—a common contaminant of emerging concern. Adsorption of SA was studied at different initial drug concentrations (in the range of 2–100 mg/L) in water solution. The Langmuir isotherm model showed the highest adsorption was achieved by bilayer composite of IZ CLI and CPyCl—around 11 mg/g. Kinetic runs were performed by using the initial drug concentration of 20 mg/L in the time interval from 0 to 75 min and pseudo-second order had good correlation with experimental data. The influence of the four different temperatures on the SA adsorption was also investigated and thermodynamic parameters suggested that the adsorption drug onto composites is an exothermic and nonspontaneous process, followed by the decrease of randomness at the solid/liquid interface during the adsorption. Zeta potential and Fourier-transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR) had been performed for the characterization of composites after adsorption of SA confirming the presence of the drug at composite surfaces.

Toxicity of fluoroquinolones on the cladoceran Daphnia magna

This study evaluates the acute and chronic toxicological effects of six fluoroquinolones on the mortality and growth of Daphnia magna. The NOECs calculated with the multivariate Probit regression model for the chronic study were 56 μg/L ciprofloxacin, 63 μg/L enrofloxacin, 78 μg/L levofloxacin, 85 μg/L marbofloxacin, 69 μg/L norfloxacin, and 141 μg/L ofloxacin. The risk quotients were determined using the measure environmental concentrations reported in water sources from different countries. The risks were low and moderate in water samples from rivers and lakes, although concentrations of ciprofloxacin, norfloxacin, and ofloxacin reported in some countries can cause toxicological damage to D. magna. In addition, urban wastewater and hospital wastewater samples constitute a threat to D. magna (high and moderate risks), requiring the treatment of these wastewater. PRACTITIONER POINTS: The NOECs calculated with the multivariate Probit model for the six fluoroquinolonas are between 56 μg/L ciprofloxacin and 141 μg/L ofloxacin. The levels of ciprofloxacin, norfloxacin, and ofloxacin in urban wastewater and hospital wastewater produce moderate and high risks for D. magna. Water and river samples from some countries containing ciprofloxacin, norlfoxacin, and ofloxacin present high risks for D. magna.

Diagnosing Down-the-Drain Disposal of Unused Pharmaceuticals at a River Catchment Level: Unrecognized Sources of Environmental Contamination That Require Nontechnological Solutions

Down-the-drain disposal of pharmaceuticals remains an overlooked and unrecognized source of environmental contamination that requires nontechnological "at-source" solutions. Monitoring of 31 pharmaceuticals over 7 days in five wastewater treatment plants (WWTPs) serving five cities in South-West UK revealed down-the-drain codisposal of six pharmaceuticals to three WWTPs (carbamazepine and propranolol in city A, sildenafil in city B, and diltiazem, capecitabine, and sertraline in city D), with a one-off record codisposal of estimated 253 pills = 40 g of carbamazepine and estimated 96 pills = 4 g of propranolol in city A accounting for their 10- and 3-fold respective increases in wastewater daily loads. Direct disposal of pharmaceuticals was found to affect the efficiency of wastewater treatment with much higher pharmaceutical removal (decrease in daily load) during "down-the-drain disposal" days. This is due to lack of conjugated glucuronide metabolites that are cleaved during "consumption-only" days, with the release of a parent pharmaceutical counterbalancing its removal. Higher removal of pharmaceuticals during down-the-drain disposal days reduced pharmaceutical loads reaching receiving environment, albeit with significant levels remaining. The estimated daily loads in receiving water downstream from a discharge point accounted for 13.8 ± 3.4 and 2.1 ± 0.2 g day^-1 of carbamazepine and propranolol, respectively, during consumption-only days and peaked at 20.9 g day^-1 (carbamazepine) and 4.6 g day^-1 (propranolol) during down-the-drain disposal days. Actions are needed to reduce down-the-drain disposal of pharmaceuticals. Our recent work indicated that down-the-drain disposal of pharmaceuticals doubled since the last study in 2005, which may be due to the lack of information and messaging that informs people to dispose of unused medicines at pharmacies. Media campaigns that inform the public of how to safely dispose of medicines are key to improving rates of return and reducing pharmaceutical waste in the environment. The environment is a key motivator for returning unused medicines to a pharmacy and so messaging should highlight environmental risks associated with improper disposal.

Supported TiO2 in Ceramic Materials for the Photocatalytic Degradation of Contaminants of Emerging Concern in Liquid Effluents: A Review

The application of TiO₂ as a slurry catalyst for the degradation of contaminants of emerging concern (CEC) in liquid effluents has some drawbacks due to the difficulties in the catalyst reutilization. Thus, sophisticated and expensive separation methods are required after the reaction step. Alternatively, several types of materials have been used to support powder catalysts, so that fixed or fluidized bed reactors may be used. In this context, the objective of this work is to systematize and analyze the results of research inherent to the application of ceramic materials as support of TiO₂ in the photocatalytic CEC removal from liquid effluents. Firstly, an overview is given about the treatment processes able to degrade CEC. In particular, the photocatalysts supported in ceramic materials are analyzed, namely the immobilization techniques applied to support TiO₂ in these materials. Finally, a critical review of the literature dedicated to photocatalysis with supported TiO₂ is presented, where the performance of the catalyst is considered as well as the main drivers and barriers for implementing this process. A focal point in the future is to investigate the possibility of depurating effluents and promote water reuse in safe conditions, and the supported TiO₂ in ceramic materials may play a role in this scope.

Removal of Pharmaceuticals from Water by Adsorption and Advanced Oxidation Processes: State of the Art and Trends

Pharmaceutical products have become a necessary part of life. Several studies have demonstrated that indirect exposure of humans to pharmaceuticals through the water could cause negative effects. Raw sewage and wastewater effluents are the major sources of pharmaceuticals found in surface waters and drinking water. Therefore, it is important to consider and characterize the efficiency of pharmaceutical removal during wastewater and drinking-water treatment processes. Various treatment options have been investigated for the removal/reduction of drugs (e.g., antibiotics, NSAIDs, analgesics) using conventional or biological treatments, such as activated sludge processes or bio-filtration, respectively. The efficiency of these processes ranges from 20–90%. Comparatively, advanced wastewater treatment processes, such as reverse osmosis, ozonation and advanced oxidation technologies, can achieve higher removal rates for drugs. Pharmaceuticals and their metabolites undergo natural attenuation by adsorption and solar oxidation. Therefore, pharmaceuticals in water sources even at trace concentrations would have undergone removal through biological processes and, if applicable, combined adsorption and photocatalytic degradation wastewater treatment processes. This review provides an overview of the conventional and advanced technologies for the removal of pharmaceutical compounds from water sources. It also sheds light on the key points behind adsorption and photocatalysis.

Removal of non-steroidal anti-inflammatory drugs from water by zeolite-rich composites: The interference of inorganic anions on the ibuprofen and naproxen adsorption

Composites of two natural zeolites - clinoptilolite and phillipsite, and cationic surfactants (cetylpyridinium chloride and Arquad® 2HT-75) were tested for the removal of two emerging contaminants - ibuprofen and naproxen. For each zeolite-rich rock, two different modifications of the zeolitic surfaces were prepared (monolayer and bilayer surfactant coverage). The influence of the initial drug concentrations and contact time on adsorption of these drugs was followed in buffer solution. The Langmuir model showed the highest adsorption capacity for the composite characterized by a bilayered surfactant at the clinoptilolite surface: 19.7 mg/g and 16.1 mg/g for ibuprofen and naproxen, respectively. Also, to simulate real systems, drug adsorption isotherms were conducted in natural water (Grindstone creek water - Columbia, Missouri, USA) by using the best performing adsorbent; in this case, a slight decrease of drug adsorption was recorded. Kinetic runs were performed in distilled water as well as in the presence of ions such as sulfates and bicarbonates; also, in this case, the interfering agents defined an adsorption decrease for bilayer composites.

Removal of selected emerging micropollutants from wastewater treatment plant effluent by advanced non-oxidative treatment - A lab-scale case study from Serbia

The presence of 48 emerging micropollutants was tested in influent and effluent from primary and secondary treatment at a municipal wastewater treatment plant (WWTP) in Serbia. Sixteen emerging micropollutants (active pharmaceutical ingredients, bisphenols, parabens and UV filters) had concentrations >LOQ (max. conc. 33.4 μg/L). The removal efficiency of primary treatment ranged from 2.0% - 96.0%. In the case of secondary treatment, except for ketoprofen (61.0%), diclofenac (62.6%) and carbamazepine (-20.0%), all other measured micropollutants had removal efficiency above 77.0%. Advanced non-oxidative lab-scale treatments were investigated. Powdered activated carbon (PAC) adsorption achieved removal efficiencies in the range 52.4-99.9%, novel coagulation with natural coagulant isolated from beans achieved removal efficiencies in range 3.2-99.9%, conventional coagulation with ferric chloride 3.12-96.4%, combined adsorption/coagulation 2.69-99.9% and combined PAC/ultrafiltration (PAC/UF) 60-99.9%. For most of the micropollutants, their removal efficiencies were similar to that reported in the literature. Novel natural coagulant showed significant potential compared to the conventional coagulant during a short episode of sub-optimal WWTP operation. When natural coagulant was applied as a part of an adsorption/coagulation hybrid process, there was no negative effect on PAC adsorption, while for conventional coagulant that was not always the case. Also, a structure property relationship (SPR) study revealed correlations between the removal efficiency of the majority of treatments applied and total polar surface area (TPSA) of the micropollutants.

Transport of emerging contaminants: a column experimental study in granitic, gneissic, and quaternary alluvial soils from Porto Alegre, Southern Brazil

Emerging contaminants is a topic that has been in evidence, especially in the last decades. These compounds are pesticides, pharmaceuticals, and personal care products that are present in several locations, mainly in large urban centers. The aim of this work was to investigate the fate of seven compounds (atrazine, simazine, ametrine, tebuthiuron, 2,4-D, fipronil, and diclofenac) using leaching column experiments to evaluate accumulation and transfer in 5 different types of urban soils from Porto Alegre, Southern Brazil. Chemical analyses were carried out through liquid chromatography tandem mass spectrometry (LC-MS/MS). The results showed that the soil derived from quaternary sediments, with well-sorted sandy sediments, was the one in which the contaminants had higher mobility. This soil also has a pH above the average of the others in the city, a factor that may also be responsible for less retention of substances. Tebuthiuron is the substance with the greatest leaching potential overall. Column experiments are a relevant tool to understand the behavior of emerging contaminants in soils and implications on the population health.

Removal of pharmaceutical and personal care products (PPCPs) from wastewater using microalgae: A review

Pharmaceuticals and personal care products (PPCPs) are a group of emerging micro-pollutants causing detrimental effects on living organisms even at low doses. Previous investigations have confirmed the presence of PPCPs in the environment at hazardous levels, mainly due to the inefficiency of conventional wastewater treatment plants (CWWTPs). Their stable structure induces longer persistence in the environment. Microalgae are currently used to bioremediate numerous pollutants of different characteristics and properties released from the domestic, industrial, agricultural, and farm sectors. CO₂ mitigation during culture and the use of biomass as feedstock for biodiesel or biofuel production are, briefly, other benefits of microalgae-mediated treatment over CWWTPs. This review provides a comprehensive summary of recent literature, an overview of approaches and treatment systems, and breakthrough in the field of algal-mediated removal of PPCPs in wastewater treatment processes. The mechanisms involved in phycoremediation, along with their experimental approaches, have been discussed in detail. Factors influencing the removal of PPCPs from aqueous media are comprehensively described and assessed. A comparative study on microalgal strains is analyzed for a more efficient implementation of future processes. The role of microalgae to mitigate the most severe environmental impacts of PPCPs and the generation of antibiotic-resistant bacteria is discussed. Also, a detailed assessment of recent research on potential toxic effects of PPCPs on microalgae was conducted. The current review highlights microalgae as a promising and sustainable approach to efficiently bio-transform or bio-adsorb PPCPs.

Environmental Distribution of Personal Care Products and Their Effects on Human Health

Personal care products (PCPs) are generally used for personal hygiene, cleaning, grooming, and beautification. These include hair and skin care products, baby care products, UV blocking creams, facial cleansers, insect repellents, perfumes, fragrances, soap, detergents, shampoos, conditioners, toothpaste, etc., thus exposing humans easily. Personal preferences related to PCPs usage frequency are highly variable and depend on socioeconomic status and lifestyle factors. The increasing availability and diversity of PCPs from the retailer outlets consequently result in higher loading of PCPs into wastewater systems and, therefore, the environment. These compounds persistently and continuously release biologically active and inactive ingredients in the atmosphere, biosphere, geosphere, and demonstrating adverse effects on human, wild, and marine life. Advanced techniques such as granular activated carbon filtration and algae-based system may help biotransformation and remove PCP contaminants from water with improved efficiency. Additionally, harmony among PCPs related regulations of different countries may encourage standard checks to control their manufacturing, sale, and distribution across the borders to ensure consumers' safety. Furthermore, all intended ingredients, their concentrations, and instructions for frequency of use as per age groups may be clearly labeled on packages of PCPs. In conclusion, the emerging environmental contaminants of PCPs and their association with the growing risks of negative effects on human health and globally on the environment emphasize the chemical-free simple lifestyle.

Non-steroidal anti-inflammatory drugs in the environment: Where were we and how far we have come?

Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most well-known pharmaceuticals with a broad scope of properties that are widely used in human and veterinary medicine. Because of their extensive utilization, NSAIDs are commonly identified in the environment as trace emerging contaminants. Regardless of vast experience with these drugs, NSAIDs are full of contradictions that trigger major concerns for environmental researchers. A limited understanding on NSAID's occurrence, distribution and eco-toxicological effects have led to an escalated dilemma in the last decade. Thus, a broad-spectrum study covering all aspects of occurrence, detection and removal is required to meet the fundamental levels of knowledge on the effects of NSAIDs in all exposed environmental aspects. Therefore, this paper focuses on classifying the sources and entry points of residual NSAIDs. Further, detecting and regulating their concentrations in both input streams and receiving environments, along with the removal processes of this specific class of emerging compounds, in the direction of developing a management policy is comprehensively reviewed.

White rot fungi can be a promising tool for removal of bisphenol A, bisphenol S, and nonylphenol from wastewater

Endocrine-disrupting chemicals (EDC) are a wide group of chemicals that interfere with the endocrine system. Their similarity to natural steroid hormones makes them able to attach to hormone receptors, thereby causing unfavorable health effects. Among EDC, bisphenol A (BPA), bisphenol S (BPS), and nonylphenol (NP) seem to be particularly harmful. As the industry is experiencing rapid expansion, BPA, BPS, and NP are being produced in growing amounts, generating considerable environmental pollution. White rot fungi (WRF) are an economical, ecologically friendly, and socially acceptable way to remove EDC contamination from ecosystems. WRF secrete extracellular ligninolytic enzymes such as laccase, manganese peroxidase, lignin peroxidase, and versatile peroxidase, involved in lignin deterioration. Owing to the broad substrate specificity of these enzymes, they are able to remove numerous xenobiotics, including EDC. Therefore, WRF seem to be a promising tool in the abovementioned EDC elimination during wastewater treatment processes. Here, we review WRF application for this EDC removal from wastewater and indicate several strengths and limitations of such methods.

Determination of Endocrine Disrupting Chemicals in Water and Wastewater Samples by Liquid Chromatography-Negative Ion Electrospray Ionization-Tandem Mass Spectrometry

A liquid chromatography-negative ion electrospray ionization-tandem mass spectrometry method was developed for the simultaneous analysis of bisphenol A, 4-octylphenol, 4-nonylphenol, diethylstilbestrol, 17β-estradiol, estriol, estrone, 17α-ethinylestradiol, prednisone, and prednisolone. This method used solid-phase extraction with an elution solvent of acetonitrile to improve the stability of the analytes. To maintain the stability of analytes analyses were completed within five days. The recoveries ranged from 84 to 112% and the relative standard deviation of analysis of duplicate samples was <10%. The limits of quantitation were 1–10 ng/L. Surface water and wastewater were obtained from five wastewater treatment plants in Saskatchewan. Matrix effects were moderate to severe. Using standard addition calibration, all analytes except diethylstilbestrol and 17α-ethinyl estradiol were detected. There was a low frequency of detection of the target analytes in upstream and downstream water, indicating good removal efficiency during the wastewater treatment process. Bisphenol A and 4-nonylphenol were the only analytes detected downstream. Bisphenol A was the most frequently detected in raw wastewater (133 to 403 ng/L). Estriol was detected more often in raw wastewater than estrone or 17β-estradiol. This is the first Canadian study with the detection of prednisone and prednisolone with concentrations at 198–350 ng/L in raw wastewater at 60% of the wastewater treatment plants.

Occurrence and assessment of environmental risks of endocrine disrupting compounds in drinking, surface and wastewaters in Serbia

The present study is the first comprehensive monitoring of 13 selected endocrine disrupting compounds (EDCs) in untreated urban and industrial wastewater in Serbia to assess their impact on the Danube River basin and associated freshwaters used as sources for drinking water production in the area. Results showed that natural and synthetic estrogens were present in surface and wastewater at concentrations ranging from 0.1 to 64.8 ng L^-1. Nevertheless, they were not detected in drinking water. For alkylphenols concentrations ranged from 1.1 to 78.3 ng L^-1 in wastewater and from 0.1 to 37.2 ng L^-1 in surface water, while in drinking water concentrations varied from 0.4 to 7.9 ng L^-1. Bisphenol A (BPA) was the most abundant compound in all water types, with frequencies of detection ranging from 57% in drinking water, to 70% in surface and 84% in wastewater. Potential environmental risks were characterized by calculating the risk quotients (RQs) and the estrogenic activity of EDCs in waste, surface and drinking water samples, as an indicator of their potential detrimental effects. RQ values of estrone (E1) and estradiol (E2) were the highest, exceeding the threshold value of 1 in 60% of wastewater samples, while in surface water E1 displayed potential risks in only two samples. Total estrogenic activity (EEQ_t) surpassed the threshold of 1 ng E2 L^-1 in about 67% of wastewater samples, and in 3 surface water samples. In drinking water, EEQ_t was below 1 ng L^-1 in all samples.

Sulfamethoxazole/Trimethoprim ratio as a new marker in raw wastewaters: A critical review

Global Trimethoprim (TMP) and Sulfamethoxazole (SMX) occurrences in raw wastewaters were systematically collected from the literature (n = 140 articles) in order to assess the relevance of using the SMX/TMP ratio as a marker of the main origin of wastewaters. These two antibiotics were selected due to their frequent use in association (i.e. co-trimoxazole) in a 5:1 ratio (SMX:TMP) for medication purposes, generating a unique opportunity to globally evaluate the validity of this ratio based on concentration values. Several parameters (e.g. sorption, biodegradation) may affect the theoretical SMX/TMP ratio. However, the collected data highlighted the good agreement between the theoretical ratio and the experimental one, especially in wastewater treatment plant influents and hospital effluents. Only livestock effluents displayed a very high SMX/TMP ratio, indicative of the very significant use of sulfonamide alone in this industry. Conversely, several countries displayed low SMX/TMP ratio values, highlighting local features in the human pharmacopoeia. This review provides new insights in order to develop an easy to handle and sound marker of wastewater origins (i.e. human/livestock), beyond atypical local customs.

Ionic liquid-based ultrasound-assisted emulsification microextraction for the determination of ranitidine in water samples and pharmaceutical preparations

A new extraction method is proposed for the isolation of the histamine H₂ receptor antagonist ranitidine (RNT) from aqueous samples.

Introduction to wastewater microbiology: special emphasis on hospital wastewater

The important role of proper sanitation in maintaining good public health has been confirmed in the past years. Wastewater treatment plants (WWTPs) serve as efficient processes in removing pathogens, organic pollutants, nutrients, and pharmaceuticals from wastewaters. However, the advance systems of treatment that we use today are the result of a series of inventions that have been performed since 19th century. This chapter explains the evolution of the wastewater origin and the treatment processes along with the developments in microbiology and pathology that led to the present-day scenario of research and advance facilities. Pharmaceuticals can easily enter the environment due to their incomplete degradation in the treatment processes and because of their adverse effects on organisms and environment they are becoming a matter of great concern. A brief discussion on the presence of pharmaceutical compounds in different environment sectors such as wastewater, WWTPs, and the natural aquatic environment has been provided.

Evaluation of caffeine adsorption by MgAl-LDH/biochar composite

In the present work, the composite MgAl-LDH/biochar using activated carbon from bovine bone as support for the layered double hydroxide particles was successfully synthesised and used as an alternative adsorbent for caffeine removal from water. Kinetic studies showed that the equilibrium was achieved in only 20 min of contact between the adsorbent and the adsorbate. The pseudo-first-order model represented the experimental data more satisfactorily (R² = 0.95), suggesting a physical adsorption process. The isotherms were performed at three temperatures, in which it was observed the decrease in the adsorption in higher temperatures. It was obtained a maximum adsorption capacity of 26.219 mg/g at 40 °C, and the experimental data were better adjusted by Redlich-Peterson, R² > 0.9942. In short, the study demonstrated that the composite was satisfactorily synthesised and its use in the caffeine removal was quite attractive, being a potential adsorbent for water treatment applications.

Distribution and ecological risk of pharmaceuticals in surface water of the Yeongsan river, Republic of Korea

This study examined the distribution of pharmaceuticals in Yeongsan River and at point sources (PSs) in the associated water system, and performed a risk assessment based on our findings. The samples included effluents collected from three sewage treatment plants (PS1, PS2, and PS3) and two industrial complexes (PS4 and PS5) as well as surface water collected from seven mainstreams and 11 tributaries of the river. The target pharmaceuticals were acetylsalicylic acid, carbamazepine, clarithromycin, naproxen, sulfamethazine, sulfamethoxazole, sulfathiazole, and trimethoprim, which were detected by liquid chromatography-tandem mass spectrometry. All pharmaceuticals except acetylsalicylic acid and sulfathiazole were found in PS1, PS2, and PS3 samples, whereas acetylsalicylic acid, carbamazepine, sulfamethazine, and sulfamethoxazole were found in PS4, most of the pharmaceuticals were not present in PS5. The rank order of pharmaceutical concentration in surface water was carbamazepine (97.2%, 0.2067 μg/L) > sulfamethoxazole (88.9%, 0.1132 μg/L) > naproxen (51.4%, 0.0516 μg/L) > clarithromycin (43.1%, 0.0427 μg/L). The distribution of pharmaceuticals in the Yeongsan River at PSs and non-PSs differed, and higher concentrations of human pharmaceuticals were detected in upstream and midstream areas whereas higher concentrations of animal pharmaceuticals were found downstream. Hazard quotients (HQs) evaluated at each sites based on mean concentration and 95% upper confidence limits (95% UCLs) were all less than one, indicating a low risk of toxicity. The findings of this study are expected to be useful for risk assessment of aquatic ecosystems.

Prospects for finding Junge variability-lifetime relationships for micropollutants in the Danube river

Persistence of chemical pollutants is difficult to measure in the field. Junge variability-lifetime relationships, correlating the relative standard deviation of measured concentrations with residence time, have been used to estimate persistence of air pollutants. Junge relationships for micropollutants in rivers could provide evidence that half-lives of compounds estimated from laboratory and field data are representative of half-lives in a specific system, location and time. Here, we explore the hypothesis that Junge relationships could exist for micropollutants in the Danube river using: (1) concentrations of six hypothetical chemicals modeled using the STREAM-EU fate and transport model, and (2) concentrations of nine micropollutants measured in the third Joint Danube Survey (JDS3) combined with biodegradation half-lives reported in the literature. Using STREAM-EU, we found that spatial and temporal variability in modeled concentrations was inversely correlated with half-life for the four micropollutants with half-lives ≤90 days. For these four modeled micropollutants, we found Junge relationships with slopes significantly different from zero in the temporal variability of concentrations at 88% of the 67 JDS3 measurement sites, and in the spatial variability of concentrations on 36% out of 365 modeled days. A Junge relationship significant at the 95% confidence level was not found in the spatial variability of nine micropollutants measured in the JDS3, nor in STREAM-EU-modeled concentrations extracted for the dates and locations of the JDS3. Nevertheless, our model scenarios suggest that Junge relationships might be found in future measurements of spatial and temporal variability of micropollutants, especially in temporal variability of pollutants measured downstream in the Danube river.

Characterization of wastewater effluents in the Danube River Basin with chemical screening, in vitro bioassays and antibiotic resistant genes analysis

Averaged 7-day composite effluent wastewater samples from twelve wastewater treatment plants (WWTPs) in nine countries (Romania, Serbia, Hungary, Slovenia, Croatia, Slovakia, Czechia, Austria, Germany) in the Danube River Basin were collected. WWTPs' selection was based on countries' dominant technology and a number of served population with the aim to get a representative holistic view of the pollution status. Samples were analyzed for 2248 chemicals of emerging concern (CECs) by wide-scope target screening employing LC-ESI-QTOF-MS. 280 compounds were detected at least in one sample and quantified. Spatial differences in the concentrations and distribution of the compounds classes were discussed. Additionally, samples were analyzed for the possible agonistic/antagonistic potencies using a panel of in vitro transactivation reporter gene CALUX® bioassays including ERα (estrogenics), anti-AR (anti-androgens), GR (glucocorticoids), anti-PR (anti-progestins), PPARα and PPARγ (peroxisome proliferators) and PAH assays. The potency of the wastewater samples to cause oxidative stress and induce xenobiotic metabolism was determined using the Nrf2 and PXR CALUX® bioassays, respectively. The signals from each of the bioassays were compared with the recently developed effect-based trigger values (EBTs) and thus allowed for allocating the wastewater effluents into four categories based on their measured toxicity, proposing a putative action plan for wastewater operators. Moreover, samples were analyzed for antibiotics and 13 antibiotic-resistant genes (ARGs) and one mobile genetic element (intl1) with the aim to assess the potential for antibiotic resistance. All data collected from these various types of analysis were stored in an on-line database and can be viewed via interactive map at https://norman-data.eu/EWW_DANUBE.

Life cycle assessment of advanced wastewater treatment processes: Involving 126 pharmaceuticals and personal care products in life cycle inventory

Continuous exposure to pharmaceuticals and personal care products (PPCPs) is a critical concern given potential toxicity impacts on aquatic environments and human health, although concentrations of PPCPs in the environment are low. While several studies have focused on the fate and toxicity of organic micropollutants in wastewater, the environmental impacts of life cycle assessment induced by these organic micropollutants in advanced wastewater treatment processes are still unknown. To address this need, an environmental evaluation of three representative advanced wastewater treatment processes (ozonation, granular activated carbon adsorption and reverse osmosis) involving PPCPs removal was conducted using life cycle assessment and USEtox model in this study. Although a large amount of PPCPs can be eliminated during conventional waste highest characterization factors for freshwater toxicity, while 17α-ethinylestradiol, sertraline, and 17β-estradiol had the highest human toxicity characterization factors. From the perspective of LCA, reverse osmosis appeared to have the greatest environmental burden due to the high energy and material consumption during the treatment process. After involving 126 PPCPs in life cycle inventory, the ecotoxicity impact results were increased significantly in three advanced wastewater treatment processes. The contribution of effluent was improved in toxicity impact category, accounting more than 25% for the three processes. The effluent (including PPCPs) as the key factor was next only to electricity and chemicals in eutrophication, ecotoxicity and human toxicity impacts category particularly. Therefore, PPCPs should not be ignored in life cycle assessment of advanced wastewater treatment processes, although they are not typically monitored in wastewater. These results are valuable for conducting a comprehensive environmental evaluation of advanced wastewater treatment processes considering micro-pollutants removal. The identified PPCPs with high freshwater and human toxicity can be considered as the priority control index of organic micropollutants for wastewater treatment plants.

The role of intraspecies variation in fish neurobehavioral and neuropharmacological phenotypes in aquatic models

Intraspecies variation is common in both clinical and animal research of various brain disorders. Relatively well-studied in mammals, intraspecies variation in aquatic fish models and its role in their behavioral and pharmacological responses remain poorly understood. Like humans and mammals, fishes show high variance of behavioral and drug-evoked responses, modulated both genetically and environmentally. The zebrafish (Danio rerio) has emerged as a particularly useful model organism tool to access neurobehavioral and drug-evoked responses. Here, we discuss recent findings and the role of the intraspecies variance in neurobehavioral, pharmacological and toxicological studies utilizing zebrafish and other fish models. We also critically evaluate common sources of intraspecies variation and outline potential strategies to improve data reproducibility and translatability.

Removal of Multi-Class Antibiotic Drugs from Wastewater Using Water-Soluble Protein of Moringa stenopetala Seeds

The removal of ten selected antibiotic drugs belonging to different classes (sulphonamides, fluoroquinolones, macrolides, and tetracycline) was investigated using water-soluble proteins from the seeds of Moringa stenopetala. The surface functional groups of water-soluble protein powder before and after removal of antibiotics were characterized using Fourier transform infrared (FTIR). Processing parameters that could affect the removal efficiency, such as initial analyte concentration, protein dosage, and pH were studied. An optimized method was applied to a real wastewater sample collected from Daspoort Wastewater Treatment Plant (WWTP) located in Pretoria, South Africa. Under optimal conditions, the results indicated good agreement between the efficiency of water-soluble proteins to remove antibiotics from the real wastewater sample and from the synthetic wastewater sample prepared in the laboratory using standard solutions with known concentrations. The percentage of removal under optimum conditions (protein dosage of 40 mg, initial analyte concentration of 0.1 mg L−1, and pH 7) was between 85.2 ± 0.01% and 96.3 ± 0.03% for standard mixture solution and from 72.4 ± 0.32% to 92.5 ± 0.84% and 70.4 ± 0.82% to 91.5 ± 0.71% for the real wastewater (effluent and influent) sample.

Identification of first and second generation ozonation transformation products of niflumic acid by LC-QToF-MS

In this study, the removal of niflumic acid (NA) and the identification of its transformation products (TPs) during ozonation was investigated. The influence of initial ozone concentration and pH value on NA's removal was tested, while suspect and non-target screening approaches were followed for the identification of ozonation TPs. The structure elucidation was based on accurate mass and isotopic pattern criteria and interpretation of the acquired MS/MS spectra. Moreover, an in-house retention time prediction model was used as a supporting tool for their identification. Results indicated the highly reactivity of NA with the molecular ozone, since the reaction was extremely fast and was completed within the first minute of the reaction. A total of thirteen TPs of NA were identified, and their proposed structures show that the oxidation occurred in the heterocyclic ring of the molecule, while the aniline-like part remained intact by ozone attack due to the presence of the three fluoride atoms, which act as electron withdrawing groups. Ozonation experiments were conducted also using the most abundant TP of NA as parent compound. Three second generation TPs of NA were detected and possible structures were proposed.

Metabolomic responses to pre-chlorinated and final effluent wastewater with the addition of a sub-lethal persistent contaminant in Daphnia magna

Consumer products such as perfluorooctanesulfonic acid (PFOS) and pharmaceuticals (PCPPs) enter aquatic ecosystems through inefficient removal during wastewater treatment. Often, the sterilization process of wastewater includes the addition of sodium hypochlorite that can react with PCPPs and other organic matter (i.e., dissolve organic matter) to generate disinfection by-products and can cause the final effluent to be more harmful to aquatic organisms. Here, we exposed Daphnia magna to two stages of wastewater, the pre-chlorinated wastewater (PreCl) and the final effluent. In addition, we exposed D. magna, to the final effluent with a concentration gradient of added PFOS, to investigate if this persistent contaminant altered the toxicity of the final effluent. After 48 h of contaminant exposure, we measured the daphnids metabolic responses to the different stages of wastewater treatment, and with the addition of PFOS, utilizing proton nuclear magnetic resonance spectroscopy and liquid chromatography tandem mass spectrometry. We found few significant changes to the metabolic profile of animals exposed to the PreCl wastewater; however, animals exposed to the final effluent displayed increases in many amino acids and decreases in some sugar metabolites. With the addition of PFOS to the final effluent, the metabolic profile shifted from increased amino acids and decreased sugar metabolites and energy molecules especially at the low and high concentrations of PFOS. Overall, our results demonstrate the metabolome is sensitive to changes in the final effluent that are caused by sterilization, and with the addition of a persistent contaminant, the metabolic profile is further altered.

Pharmaceuticals in freshwater aquatic environments: A comparison of the African and European challenge

Hundreds of tons of pharmaceutical compounds are annually dispensed and consumed worldwide. Pharmaceuticals are an important class of emerging environmental micropollutants: their presence in water bodies is an increasing environmental concern. The aim of this review paper is to provide a comprehensive review of the occurrence of pharmaceuticals in freshwater aquatic environments in the African and European context. A literature survey has been performed, resulting in 3024 data points related to environmental occurrence. The concentration levels of 71 pharmaceuticals were assessed. The top ten most frequently detected and quantified compounds in both continents were sulfamethoxazole, carbamazepine, diclofenac, trimethoprim, ibuprofen, naproxen, paracetamol (acetaminophen), ketoprofen, venlafaxine and clarithromycin. The maximum concentrations of 17β-estradiol, estriol, ciprofloxacin, sulfamethoxazole, paracetamol, naproxen reported in African aquatic environments were ~3140, ~20,000, ~125, ~100, ~215 and ~171 times higher, respectively, than the concentrations reported in European based studies. The variation in pharmaceutical consumption, partial removal of pharmaceuticals in wastewater treatment processes, and the direct discharge of livestock animal farm wastewater were identified among the major reasons for the observed differences. Several pharmaceuticals were found in aquatic environments of both continents in concentration levels higher than their ecotoxicity endpoints. In Europe, compounds such as diclofenac, ibuprofen, triclosan, sulfadimidine, carbamazepine and fluoxetine were reported in a concentration higher than the available ecotoxicity endpoints. In Africa, much more compounds reached concentrations more than the ecotoxicity endpoints, including diclofenac, ibuprofen, paracetamol, naproxen, ciprofloxacin, triclosan, trimethoprim, sulfamethoxazole, carbamazepine and fluoxetine, estriol and 17β-estradiol. Details for each therapeutic group are presented in this review.

The occurrence of contaminants of emerging concern in Slovenian and Croatian wastewaters and receiving Sava river

This study investigated the occurrence of 48 contaminants of emerging concern (CECs) in wastewater effluents from three Slovenian and three Croatian waste water treatment plants (WWTPs) representing the major inputs into the upper and middle course of the Sava River and simultaneously in the Sava River itself. Two sampling campaigns were carried out (May and July 2017). Samples were extracted using solid-phase extraction and analysed by gas chromatography - mass spectrometry. In effluents, 23 CECs were >LOQ with caffeine and the UV-filter 4-hydroxybenzophenone (H-BP) present in the highest concentrations (<49,600 ng L^-1 and <28,900 ng L^-1, respectively) and most frequently detected (detection frequency; DFr > 83.3%). Bisphenol B and E were detected for the first time in WW from Velika Gorica (May) and Zaprešić (July), respectively. In surface water (SW), 19 CECs were detected >LOQ with CAF again being the most abundant and most frequently detected (DFr = 92.9%). Bisphenols AP, CL2, P and Z were detected >LOQ for the first time in European SW. Active pharmaceutical ingredients naproxen, ketoprofen, carbamazepine and diclofenac; the preservative methyl paraben; CAF and UV-filter HM-BP were the most abundant CECs in SW and WW. An increasing trend in the total CEC load downstream was observed, indicating the cumulative effects of individual sources along the river. The Croatian Zaprešić, Zagreb and Velika Gorica WWTP effluents contributed the most towards the enhanced loads of the CECs studied probably due to their size or insufficient treatment. HM-BP was the only compound found at a levels exhibiting high environmental risk (RQ = 1.13) downstream from Ljubljana and Domžale-Kamnik WWTPs. Other SW samples that contained HM-BP, ibuprofen (API) and/or benzyl paraben (preservative) posed a medium risk to the environment. The results suggest the need for further monitoring of CECs in the Sava River Basin.

Assessment of river sediment toxicity: Combining empirical zebrafish embryotoxicity testing with in silico toxicity characterization

Quantitative chemical analyses of 428 organic contaminants (OCs) indicated the presence of 313 OCs in the sediment extracts from Sava River, Croatia. Pharmaceuticals were present in higher concentrations than pesticides thus confirming their increasing threat to freshwater ecosystems. Toxicity evaluation of the sediment extracts from four locations (Jesenice, Rugvica, Galdovo and Lukavec) using zebrafish embryotoxicity test (ZET) accompanied with semi-quantitative histopathological analyses exhibited correlation with cumulative number and concentrations of OCs at the investigated sites (10.05, 15.22, 1.25, and 9.13 μg/g respectively). Toxicity of sediment extracts and sediment was predicted using toxic unit (TU) approach and persistence, bioaccumulation and toxicity (PBT) ranking. Additionally, influential OCs and genes were identified by graph mining of the prior knowledge informed, site-specific chemical-gene interaction models. Predicted toxicity of sediment extracts (TU_ext) was similar to the results obtained by ZET and associated histopathology with Rugvica sediment being the most toxic, followed by Jesenice, Lukavec and Galdovo. Sediment TU (TU_sed) favoured OCs with low octanol-water partition coefficients like herbicide glyphosate and antibiotics ciprofloxacin and sulfamethazine thus indicating locations containing higher concentrations of these OCs (Galdovo and Rugvica) as the most toxic. Results suggest that comprehensive in silico sediment toxicity predictions advocate providing equal attention to organic contaminants with either very low or very high log K_ow.