Tracking the occurrence of psychotropic pharmaceuticals in Brazilian wastewater treatment plants and surface water, with assessment of environmental risks

Automatised online SPE-LC-MS/MS method for the enantioselective determination of chiral β-blockers and antidepressants in wastewater

BACKGROUND

Pharmacologically active compounds are emerging pollutants of greatest concern because of their continuous release to the aquatic media and potential effects on non-target organisms. Nevertheless, in spite that many pharmaceuticals are chiral compounds which enantiomers may have different environmental behaviour and effects, their enantiomeric determination has been scarcely evaluated. This fact can be explained by the great challenge to overcome when developing an analytical method for the individual determination of compounds with the same physical-chemical properties, as it is the case of enantiomers.

RESULTS

In this work, an automatised method based on online solid phase extraction (SPE) coupled to liquid chromatography-tandem mass spectrometry (LC-MS/MS) was optimised and validated for the enantiomeric determination of highly prescribed (β-blockers (atenolol, metoprolol and propranolol), antidepressants (citalopram, fluoxetine, sertraline, duloxetine and venlafaxine) and two of their metabolites in influent and effluent wastewater. Three of them (metoprolol, citalopram and venlafaxine) have been recently included in the European Union Directive 2024/3019 as substances that should be measured in wastewater. Method quantification limits in the range from 0.1 to 50 ng L-1 for most compounds. Accuracy ranged from 60.8 to 114 % and precision, expressed as relative standard deviation, was lower than 12.5 % for all the compounds. Method application to wastewater samples revealed the presence of the target compounds at concentrations between 1.06 and 1213 ng L-1 and a preferential degradation of some enantiomers: S-(-)-atenolol, metoprolol-E1, venlafaxine-E1 and O-desmethylvenlafaxine-E1.

SIGNIFICANCE AND NOVELTY

This method is the first one for online SPE-chiral-LC-MS/MS determination of two therapeutic groups of chiral pharmaceuticals in wastewater. The method allows their automatised enantiomeric determination, including sample treatment, SPE column wash and conditioning, and LC-MS/MS determination, in 40 min with enantioresolution from 0.51 to 1.24. The online SPE method developed provides a fast way to obtain information about chiral compounds in wastewater reducing labour intensity, exposure to organic solvents, analyte loss and plastic waste.

Environmental behavior, risks, and management of antidepressants in the aquatic environment

Antidepressants are increasingly detected in aquatic environments due to their incomplete removal in wastewater treatment, raising significant concerns about their ecological impacts. This review focuses on the three most widely used classes of antidepressants-tricyclic antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs), and serotonin-norepinephrine reuptake inhibitors (SNRIs). It systematically explores their physicochemical properties and how these properties influence their environmental fate, including sorption, mobility, and bioaccumulation in aquatic ecosystems. The sublethal effects of these antidepressants on aquatic organisms, particularly their impacts on behavior, reproduction, and development, are critically analyzed, highlighting potential threats to biodiversity and ecological stability. Key knowledge gaps are identified, including the long-term impacts of chronic low-dose exposure, the role of bioactive metabolites, and the combined toxicity of antidepressants with other contaminants. The review underscores the importance of advanced wastewater treatment technologies, environmentally mindful prescribing practices, and public awareness campaigns as essential measures to mitigate these risks. By addressing these challenges, this study aims to inform future research and guide sustainable environmental management strategies.

Enhanced ice slurry with low oxidant consumption for ultrafast in-situ removal of micropollutants sheltered in sediments of water supply pipelines

The cleaning of water supply pipelines represents an increasingly prevalent global practice with the aim of providing high-quality drinking water. Ice pigging, a widely-utilized pipe cleaning technique, can effectively remove substantial sediment sediments from pipe walls. During this process, micropollutants adsorbed to the sediments are inevitably released into the effluent, posing a potential threat to public health. Existing technologies can only address these micropollutants through various post-treatment methods. To improve pipeline cleaning efficiency and reduce costs, we have developed an enhanced ice slurry by adding a minute quantity of peroxymonosulfate (PMS) into the base ice slurry for ultrafast, in-situ removal of micropollutants within sediments. Comparative studies with the base ice slurry demonstrate a significant enhancement in the removal efficiency of the common micropollutant carbamazepine (CBZ) using the enhanced ice slurry. While the removal efficiency of CBZ ranged from 16 to 23 % with increasing NaCl content from 3 to 7 wt% over 10 min for the base ice slurry, nearly complete removal of CBZ was achieved within 1 min by introducing 10 μM PMS into the base ice slurry. The influence of operational parameters (e.g., PMS and Cl- concentrations, cleaning flow velocity) and pipeline characteristics (e.g., CBZ and Fe2+ concentrations, turbidity, pipe sediment) on CBZ removal efficiency was comprehensively examined for the enhanced ice slurry. The enhanced micropollutant removal process was mainly driven by active species such as hydroxyl and sulfate. Remarkably, chlorinated byproducts were scarcely detected during ice pigging, and the degradation products exhibited minimal ecotoxicity. With a cost of 0.16 Euro per cubic meter of cleaned pipe, the enhanced ice slurry presents a notable economic advantage over alternative methods. Overall, the enhanced ice slurry offers an environmentally friendly, cost-effective, and efficient solution for reducing micropollutants in water supply systems.

Electrochemical oxidation for the rapid degradation of emerging contaminants: Insights into electrolytes and process parameters for phytotoxicity reduction

Atrazine (ATZ), carbamazepine (CBZ), and sulfamethoxazole (SMX) are contaminants of emerging concern (CECs) commonly detected in water sources, posing a risk to health, sanitation, and the ecosystems. This study evaluates the degradation, mineralization, and phytotoxicity reduction of a solution containing these three CECs using an electrochemical advanced oxidation process (EAOP). Key operational parameters - pH, flow rate (Q), current density (j), and type and concentration of supporting electrolytes (NaCl and Na2SO4) - were systematically investigated. The results showed that pH had minimal impact on the process. Higher flow rates (250 L h-1) improved mineralization due to enhanced mass transfer to •OH on the anode surface. However, the flow rate had less effect on degradation, as the dominant degradation mechanisms involved chlorine- or sulfate-based oxidants. Current densities of 1 and 10 mA cm-2 produced the most favorable results, leading to efficient degradation and mineralization, along with satisfactory mineralization current efficiency (up to 47 %) and energy consumption values (91,76-3142,88 kW h kg-1). When NaCl was used as supporting electrolyte, the degradation of CECs was twice as fast as with Na2SO4, achieving over 88 % degradation in 5 min and 40 % mineralization within 60 min. While chlorinated and sulfate species enhance process efficiency, excessive electrolyte concentration should be avoided to prevent scaling and •OH scavenging. Phytotoxicity tests with Allium cepa revealed an unexpected reduction in toxicity in samples treated with NaCl, suggesting that Na2SO4 may be more phytotoxic under the tested conditions.

A novel data-driven screening method of antidepressants stability in wastewater and the guidance of environmental regulations

Wastewater-based epidemiology (WBE) represents a powerful technique for quantifying the attenuation characteristics and consumption of pharmaceuticals. In addition to WBE, no further methods have been developed to assess the wastewater stability related to antidepressants (ADs). In this study, the biodegradability, solubility, and adsorption or partition of 66 ADs were objectively scored according to the relevant guidelines of the Organisation for Economic Cooperation and Development. An assessment framework and the MSSL-RealFormer classification model of ADs wastewater stability were constructed based on physicochemical properties to predict the ADs wastewater stability and the quantitative structure-activity relationship. The constructed MSSL-RealFormer classification model exhibited a markedly higher prediction accuracy than traditional methods. Furthermore, 15 high-stable ADs in wastewater with low biodegradability, high solubility, and low adsorption or partition were identified. SHapley Additive exPlanation method demonstrated that group hydrophobicity, electrostatic and van der Waals forces exerted a significant influence on the ADs wastewater stability. And molecular stability was found to be significantly correlated with the ADs wastewater stability. A combination of density functional theory and MSSL-RealFormer classification model was employed to identify 17 high-stable transformation products of nine medium- and low-stable ADs in wastewater. The Ecological Structure Activity Relationships model demonstrated that bupropion, tapentadol and chlorpheniramine exhibited significant acute toxicity to the aquatic food chain. In this study, a novel deep learning model was constructed to rapidly screen the correlation between the ADs wastewater stability and their molecular structures. It is anticipated to prove a favorable tool for optimizing the wastewater stability screening of pharmaceuticals.

Toxic interactions between fluoxetine and microplastics in zebrafish embryonic development

The increasing use of antidepressants, especially fluoxetine (FLX), has resulted in their presence in aquatic environments due to wastewater discharges from municipal, industrial, and hospital sources. Simultaneously, microplastics (MPs) have been extensively studied in short-term (acute) exposures, showing adverse effects such as oxidative stress, behavioral alterations and neurotoxicity. However, the embryotoxic and teratogenic effects of these compounds, as well as their impacts on the survival, development, morphology, behavior, and reproduction of fish embryos in aquatic ecosystems, remain limited. This study evaluated the toxic effects of FLX (5, 40 ng/L), MPs (25, 100 particles/L) and their mixtures (FLX-MPs) at environmentally relevant concentrations. Microscopic characterization of fluorescent MPs was performed, and their presence was evaluated in Danio rerio embryos at 24 and 96 hpf, observing their localization in the chorion. In embryotoxicity and teratogenesis tests, FLX (100 ng/L) increased the rate of malformations, including deformations of the spine (CD), tail (TM) and hypopigmentation (H); MPs induced scoliosis (S), tail deformation (TM), incomplete hatching (IE) and a dose-dependent increase in malformations. FLX-MPs mixtures caused pericardial edema (PE), tail and spine deformation, delayed hatching (HR) and increased mortality. Oxidative damage analysis showed that FLX (40 ng/L) dose-dependently increased SOD and CAT activities, with an increase in cellular oxidation biomarkers (LPX, POX, HPX). Besides, MPs (100 particles/L) showed similar effects, with increased SOD, CAT, POX and HPX activities. The FLX-MPs mixture showed the most pronounced response. In gene expression, FLX (5, 40 ng/L) modulated genes such as bax, blc2 and casp3. MPs (25, 100 particles/L) induced the expression of bax, blc2, p53 and casp3. FLX-MPs mixtures (25 particles/L-40 ng/L, 100 particles/L-40 ng/L) expressed nfr1, p53, nfe2l2a and casp3. Histological damage revealed abnormal muscle fibers (AMF) and yolk sac edema (YSE) at 40 ng/L FLX, and lamellar fusion (LF) and scoliosis (S) in MPs (100 particles/L). Brain swelling (IBT) and neuromast loss (NL) were detected in FLX-MPs mixtures. In conclusion, both FLX and MPs and their combinations affect the embryonic development and physiological state of Danio rerio.

Multi-biomarker approach to assess the toxicity of carbamazepine, a neuropharmaceutical, in the female fish Astyanax lacustris (Teleostei: Characidae)

Carbamazepine (CBZ) is a pharmaceutical commonly used in the treatment of epilepsy and bipolar disorder and has been detected in different aquatic ecosystems worldwide. Considering its possible role in altering nervous system and reproduction, this study aimed to evaluate the effects of CBZ on molecular and cellular biomarkers of the teleost Astyanax lacustris. Results demonstrated that CBZ, in environmentally relevant concentrations (500 ng L-1) increases fshβ gene expression levels, decreases muscle protein content and hepatic LPO (500 ng L-1 and 1250 ng L-1 of CBZ). Nonetheless, no effects were observed towards enzymatic activities, steroid plasma levels and/or lipid content. Considering that A. lacustris inhabits clean and polluted environments, it is possible to suggest that animals possess a level of tolerance to stressors, allowing them to maintain reproductive functions regardless of environmental challenges.

Photodegradation of typical psychotropic drugs in the aquatic environment: a critical review

Continuous consumption combined with incomplete removal during wastewater treatment means residues of psychotropic drugs (PDs), including antidepressants, antipsychotics, antiepileptics and illicit drugs, are continuously entering the aquatic environment, where they have the potential to affect non-target organisms. Photochemical transformation is an important aspect to consider when evaluating the environmental persistence of PDs, particularly for those present in sunlit surface waters. This review summarizes the latest research on the photodegradation of typical PDs under environmentally relevant conditions. According to the analysis results, four classes of PDs discussed in this paper are influenced by direct and indirect photolysis. Indirect photodegradation has been more extensively studied for antidepressants and antiepileptics compared to antipsychotics and illicit drugs. Particularly, the photosensitization process of dissolved organic materials (DOM) in natural waters has received significant research attention due to its ubiquity and specificity. The direct photolysis pathway plays a less significant role, but it is still relevant for most PDs discussed in this paper. The photodegradation rates and pathways of PDs are influenced by various water constituents and parameters such as DOM, nitrate and pH value. The contradictory results reported in some studies can be attributed to differences in experimental conditions. Based on this analysis of the existing literature, the review also identifies several key aspects that warrant further research on PD photodegradation. These results and recommendations contribute to a better understanding of the environmental role of water matrixes and provide important new insights into the photochemical fate of PDs in aquatic environments.

Population size, income and poor sanitation interact to explain widespread streamwater contamination by antidepressants in the Metropolitan Region of São Paulo

The expansion of urban settlements over native environments may expose biodiversity to a host of emerging contaminants, with unintended ecological effects. This study evaluated patterns of contamination of streamwater by antidepressants in the Upper Tietê River Basin, a watershed of high social, economic and environmental relevance for comprising both the largest urban settlement in South America (the Metropolitan Region of São Paulo) and remnants of a globally important biodiversity hotspot (the Atlantic Rainforest). We sampled 53 third-order streams draining catchments regularly distributed across a gradient in urban cover. Antidepressant contamination was found to be widespread. Whereas no antidepressants were detected in any of the 11 streams draining entirely forested catchments, 39 of 42 remaining streams were contaminated with one to eight antidepressant molecules. Concentrations increased monotonically with urban cover and bracketed the entire range found in global freshwaters. Concentrations increased with the number of inhabitants in the catchment and with number of households with no sanitation, but only in catchments with higher mean per capita income. Although concentrations in the range of tens to hundreds of nanograms-per-liter as found may appear to be low, literature data demonstrate effects on individual performance, population growth rates, and even transgenerational effects in which short-term exposure at the embryonic stage may affect life history traits over three generations of descendants. These findings highlight the need to expand sanitation infrastructure and to adopt policies of urban planning that reconcile human settlement with biodiversity conservation in Latin America.

Maternal Daphnia magna exposure to the antidepressant sertraline causes molting disorder, multi-generational reproductive and serotonergic dysfunction

Sertraline, one of the most commonly used antidepressants, has exhibited a progressively escalating trend in usage over the course of the last decades years, which have been exacerbated by the COVID-19 pandemic. Here, this study assessed the transgenerational effects of sertraline on the aquatic microcrustacean Daphnia magna, a parthenogenetic model species. The parental D. magna (G0) were exposed to environmentally relevant concentrations of sertraline (0.1 and 10 μg/L) for 21 days at individual and population level, and observed exposure triggered specific increased fecundity and desynchronized molting. These alterations were partially inherited through three subsequent non-exposed generations (G1, G2, and G3), as evidenced by increased fecundity and disordered molting in G1, reduced fecundity in G2, and reduced body size of G3-offspring. The molt-related genes neverland 1 and hormone receptor 3 were significantly different to the control group simultaneously only in the exposed generation, which may well be responsible for the molting asynchrony. Vitellogenin plays an important role in reproduction, and our results indicate that its abnormal expression persists up to G3, which was highly correlated with the expression of serotonin transporter, the drug target of sertraline. This finding suggested that sertraline possesses a sustained reproductive toxicity and disrupting potential and may be associated with serotonin dysregulation caused by compensatory feedback of serotonin transporter. In combination with male birth and upregulation of doublesex and vitellogenin, sertraline was deemed to trigger a self-defense response of D. magna, known as "abandon-ship" by increasing reproductive inputs. However, no males was found in individual reproduction test in each generation, which may suggest some interaction between sertraline and population density. Our findings emphasize that the toxic effects of sertraline can be transferred to unexposed generations, even with different adverse consequences, implying that future studies need to focus on transgenerational delayed effects and the underlying mechanisms.

Anaerobic digestion and biochar/hydrochar enhancement of antibiotic-containing wastewater: Current situation, mechanism and future prospects

The increasing consumption of antibiotics by humans and animals and their inappropriate disposal have increased antibiotic load in municipal and pharmaceutical industry waste, resulting in severe public health risks worldwide. Anaerobic digestion (AD) is the main force of antibiotic-containing wastewater treatment, and the adaptability of biochar/hydrochar (BC/HC) makes it an attractive addition to AD systems, which aim to promote methane production efficiency. Nevertheless, further studies are needed to better understand the multifaceted function of BC/HC and its role in antibiotic-containing wastewater AD. This review article examines the current status of AD of antibiotic-containing wastewater and the effects of different preparation conditions on the physicochemical properties of BC/HC and AD status. The incorporation of BC/HC into the AD process has several potential benefits, contingent upon the physical and chemical properties of BC/HC. These benefits include mitigation of antibiotic toxicity, establishment of a stable system, enrichment of functional microorganisms and enhancement of direct interspecies electron transfer. The mechanism by which BC/HC enhances the AD of antibiotic-containing wastewater, with focus on microbial enhancement, was analysed. A review of the literature revealed that the challenge of optimization and process improvement must be addressed to enhance efficiency and clarify the mechanism of BC/HC in the AD of antibiotic-containing wastewater. This review aims to provide significant insights and details into the BC/HC-enhanced AD of antibiotic-containing wastewater.

Insights into the sunlight-Induced photodegradation mechanisms of methamphetamine in surface water driven by NO₃⁻, HCO₃⁻ and Fe3

Psychoactive substances abuse is a global issue, with the methamphetamine (METH) being the most used and produced illicit substance in recent years. METH has been recognized as emerging contaminants in aquatic ecosystems. Research on the removal of METH from surface water is still lacking in-depth exploration. The effects of key aqueous environmental factors on the photodegradation of METH were investigated in this study. NO₃⁻, Fe3+ and dissolved organic matter (DOM) enhanced the photodegradation of METH, respectively, with degradation rates increasing as their concentrations increased. When HCO₃⁻ coexisted with NO₃⁻, it exhibited dual effects on METH photodegradation: low concentrations inhibited the process, whereas high concentrations promoted it. The primary photodegradation products of METH, such as OH-METH, (OH)2-METH, AMP and NO2-OH-METH, were identified. The latter two compounds were newly discovered in this study. The mechanism of NO₃⁻, HCO₃⁻ and Fe3+ accelerating the photodegradation of METH in water was proposed to proceed via the generation of hydroxyl radical (HO∙), leading to the oxidation of METH, along with the involvement of nitro radical (∙NO2) and carbonate radical (CO3•-).

Deep learning-assisted detection of psychoactive water pollutants using behavioral profiling of zebrafish embryos

Water pollution poses a significant risk to the environment and human health, necessitating the development of innovative detection methods. In this study, a series of representative psychoactive compounds were selected as model pollutants, and a new approach combining zebrafish embryo behavioral phenotyping with deep learning was used to identify and classify water pollutants. Zebrafish embryos were exposed to 17 psychoactive compounds at environmentally relevant concentrations (1 and 10 μg/L), and their locomotor behavior was recorded at 5 and 6 days post-fertilization (dpf). We constructed six distinct zebrafish locomotor track datasets encompassing various observation times and developmental stages and evaluated multiple deep learning models on these datasets. The results demonstrated that the ResNet101 model performed optimally on the 1-min track dataset at 6 dpf, achieving an accuracy of 65.35 %. Interpretability analyses revealed that the model effectively focused on the relevant locomotor track features for classification. These findings suggest that the integration of zebrafish embryo behavioral analysis with deep learning can serve as an environmentally friendly and economical method for detecting water pollutants. This approach offers a new perspective for water quality monitoring and has the potential to assist existing chemical analytical techniques in detection, thereby advancing environmental toxicology research and water pollution control efforts.

Antidepressants and COVID-19: Increased use, occurrence in water and effects and consequences on aquatic environment. A review

The COVID-19 pandemic changed the consumption of many drugs, among which antidepressants stand out. This review evaluated the frequency of antidepressant use before and after COVID-19. Once the most consumed antidepressants were identified, detecting a variation in the frequency of consumption on the different continents, an overview of their life cycle was carried out, specifying which antidepressants are mostly detected and the places where there is a greater concentration. In addition, the main metabolites of the most used antidepressants were also investigated. A correlation between the most consumed drugs and the most detected was made, emphasizing the lack of information on the occurrence of some of the most consumed antidepressants. Subsequently, studies on the effects on aquatic life were also reviewed, evaluated through different living beings (fish, crustaceans, molluscs, planktonic crustaceans and algae). Likewise, many of the most used antidepressants lack studies on potential adverse effects on aquatic living beings. This review underscores the need for further research, particularly focusing on the life cycle of the most prescribed antidepressants. In particular, it is a priority to know the occurrence and adverse effects in the aquatic environment of the most used antidepressants after the pandemic.

Which emerging micropollutants deserve more attention in wastewater in the post-COVID-19 pandemic period? Based on distribution, risk, and exposure analysis

Aggravated accumulation of emerging micropollutants (EMs) in aquatic environments, especially after COVID-19, raised significant attention throughout the world for safety concerns. This article reviews the sources and occurrence of 25 anti-COVID-19 related EMs in wastewater. It should be pointed out that the concentration of anti-COVID-19 related EMs, such as antivirals, plasticizers, antimicrobials, and psychotropic drugs in wastewater increased notably after the pandemic. Furthermore, the ecotoxicity, ecological, and health risks of typical EMs before and after COVID-19 were emphatically compared and analyzed. Based on the environmental health prioritization index method, the priority control sequence of typical EMs related to anti-COVID-19 was identified. Lopinavir (LPV), venlafaxine (VLX), di(2-ethylhexyl) phthalate (DEHP), benzalkonium chloride (BAC), triclocarban (TCC), di-n-butyl phthalate (DBP), citalopram (CIT), diisobutyl phthalate (DIBP), and triclosan (TCS) were identified as the top-priority control EMs in the post-pandemic period. Besides, some insights into the toxicity and risk assessment of EMs were also provided. This review provides direction for proper understanding and controlling the EMs pollution after COVID-19, and is of significance to evaluate objectively the environmental and health impacts induced by COVID-19.

Recent progress in electro-Fenton technology for the remediation of pharmaceutical compounds in aqueous environments

The global focus on wastewater treatment has intensified in the contemporary era due to its significant environmental and human health impacts. Pharmaceutical compounds (PCs) have become an emerging concern among various pollutants, as they resist conventional treatment methods and pose a severe environmental threat. Advanced oxidation processes (AOPs) emerge as a potent and environmentally benign approach for treating recalcitrant pharmaceuticals. To address the shortcomings of traditional treatment methods, a technology known as the electro-Fenton (EF) method has been developed more recently as an electrochemical advanced oxidation process (EAOP) that connects electrochemistry to the chemical Fenton process. It has shown effective in treating a variety of pharmaceutically active compounds and actual wastewaters. By producing H2O2 in situ through a two-electron reduction of dissolved O2 on an appropriate cathode, the EF process maximizes the benefits of electrochemistry. Herein, we have critically reviewed the application of the EF process, encompassing diverse reactor types and configurations, the underlying mechanisms involved in the degradation of pharmaceuticals and other emerging contaminants (ECs), and the impact of electrode materials on the process. The review also addresses the factors influencing the efficiency of the EF process, such as (i) pH, (ii) current density, (iii) H2O2 concentration, (iv) and others, while providing insight into the scalability potential of EF technology and its commercialization on a global scale. The review delves into future perspectives and implications concerning the ongoing challenges encountered in the operation of the electro-Fenton process for the treatment of PCs and other ECs.

Environmentally relevant concentrations of the tricyclic antidepressant, amitriptyline, affect feeding and reproduction in a freshwater mollusc

Antidepressant drugs (ADDs) are one of the most extensively used pharmaceuticals globally. They act at particularly low therapeutic concentrations to modulate monoamine neurotransmission, which is one of the most evolutionary conserved pathways in both humans and animal species including invertebrates. As ADDs are widely detected in the aquatic environment at low concentrations (ng/L to low µg/L), their potential to exert drug-target mediated effects in aquatic species has raised serious concerns. Amitriptyline (AMI) is the most widely used tricyclic ADD, while monoamines, the target of ADDs, are major bioregulators of multiple key physiological processes including feeding, reproduction and behaviour in molluscs. However, the effects of AMI on feeding, reproduction and mating behaviour are unknown in molluscs despite their ecological importance, diversity and reported sensitivity to ADDs. To address this knowledge gap, we investigated the effects of environmentally relevant concentrations of AMI (0, 10, 100, 500 and 1000 ng/L) on feeding, reproduction and key locomotor behaviours, including mating, in the freshwater gastropod, Biomphalaria glabrata over a period of 28 days. To further provide insight into the sensitivity of molluscs to ADDs, AMI concentrations (exposure water and hemolymph) were determined using a novel extraction method. The Fish Plasma Model (FPM), a critical tool for prioritization assessment of pharmaceuticals with potential to cause drug target-mediated effects in fish, was then evaluated for its applicability to molluscs for the first time. Disruption of food intake (1000 ng/L) and reproductive output (500 and 1000 ng/L) were observed at particularly low hemolymph levels of AMI, whereas locomotor behaviours were unaffected. Importantly, the predicted hemolymph levels of AMI using the FPM agreed closely with the measured levels. The findings suggest that hemolymph levels of AMI may be a useful indicator of feeding and reproductive disruptions in wild population of freshwater gastropods, and confirm the applicability of the FPM to molluscs for comparative pharmaceutical hazard identification.

Non-targeted identification of tianeptine photodegradation products in water samples by UHPLC-QTOF MS/MS

This study aims the characterization of several tianeptine transformation products in ultrapure water by simulated sunlight irradiation. Tianeptine was completely degraded after 106 h of exposition following pseudo-first-order kinetics (half-life time = 12.0 ± 2.4 h). Furthermore, an ultra-high-performance liquid chromatography coupled with a high-resolution quadrupole time-of-flight-mass spectrometry method was developed and fully validated taking into account different method performance parameters for the quantification of tianeptine in river water up to a concentration of 400 pg L-1. Following a non-targeted approach based on mass data-independent acquisition, eight different transformation products not previously reported in the literature were identified and accordingly elucidated, proposing a photodegradation mechanism based on the accurate tandem mass spectrometry information acquired. Irradiation experiments were replicated for a tianeptine solution prepared in a blank river water sample, resulting in the formation of the same transformation products and similar degradation kinetics. In addition, a toxicity assessment of the photoproducts was performed by in silico method, being generally all TPs of comparable toxicity to the precursor except for TP1, and showing a similar persistence in the environment except for TP2 and TP6, while TP4 was the only TP predicted as mutagenic. The developed method was applied for the analysis of four river water samples.

Exposure Effects of Environmentally Relevant Concentrations of the Tricyclic Antidepressant Amitriptyline in Early Life Stage Zebrafish

Antidepressants are one of the most globally prescribed classes of pharmaceuticals, and drug target conservation across phyla means that nontarget organisms may be at risk from the effects of exposure. Here, we address the knowledge gap for the effects of chronic exposure (28 days) to the tricyclic antidepressant amitriptyline (AMI) on fish, including for concentrations with environmental relevance, using zebrafish (Danio rerio) as our experimental model. AMI was found to bioconcentrate in zebrafish, was readily transformed to its major active metabolite nortriptyline, and induced a pharmacological effect (downregulation of the gene encoding the serotonin transporter; slc6a4a) at environmentally relevant concentrations (0.03 μg/L and above). Exposures to AMI at higher concentrations accelerated the hatch rate and reduced locomotor activity, the latter of which was abolished after a 14 day period of depuration. The lack of any response on the features of physiology and behavior we measured at concentrations found in the environment would indicate that AMI poses a relatively low level of risk to fish populations. The pseudopersistence and likely presence of multiple drugs acting via the same mechanism of action, however, together with a global trend for increased prescription rates, mean that this risk may be underestimated using current ecotoxicological assessment paradigms.

Refining the correction factor for a better monitoring of antidepressant use by wastewater-based epidemiology: A case study of amitriptyline

Wastewater-based epidemiology (WBE) is proposed as a cost-effective approach to objectively monitor the antidepressant use but it requires more accurate correction factors (CF) than what had been used in previous studies. Amitriptyline is a popular prescription medicine for treating depression and nerve pain, which could be prone to misuse and need monitoring. The CF of amitriptyline employed in previous WBE studies varied from 10 to 100, leading to substantial disparities between WBE estimates and expected mass of antidepressants in wastewater. Hence, this study aimed to take amitriptyline as a case study and refine the CF by correlating mass loads measured in wastewater from 12.2 million inhabitants collected during the 2016 Census with corresponding annual sales data. The triangulation of WBE data and sales data resulted in a newly-derived CF of 7, which is significantly different from the CF values used in previous studies. The newly derived CF was applied to a secondary, multi-year (2017 to 2020) WBE dataset for validation against sales data in the same period, demonstrating the estimated amitriptyline use (380 ± 320 mg/day/1000 inhabitants) is consistent with sales data (450 ± 190 mg/day/1000 inhabitants). When we applied the new CF to previous studies, the wastewater consumption loads matched better to prescription data than previous WBE estimations. The refined CF of amitriptyline can be used in future WBE studies to improve the accuracy of the consumption estimates.

Green synthesis of chitosan-encapsulated CuO nanocomposites for efficient degradation of cephalosporin antibiotics in contaminated water

The synthesis and characterization of chitosan encapsulated copper oxide nanocomposites (CuNPs) using plant extracts for the photocatalytic degradation of second-generation antibiotics, cefixime and cefuroxime, were investigated. The study revealed that the presence of diverse chemical components in the plant extract significantly influenced the size of the CuNPs, with transmission electron microscopy (TEM) showing spherical shapes and sizes ranging from 11-35 nm. The encapsulation process was confirmed by an increase in size for certain samples, indicating successful encapsulation. X-ray photoelectron spectroscopy (XPS) analysis further elucidated the chemical makeup, confirming the valency state of Cu2+ and the presence of Cu-O bonding, with no contaminants detected. Photocatalytic activity assessments demonstrated that the copper oxide nanocomposites exhibited significant degradation capabilities against both antibiotics under UV light irradiation, with encapsulated nanocomposites (EnCu30) showing up to 96.18% degradation of cefuroxime within 60 min. The study highlighted the influence of chitosan encapsulation on enhancing photocatalytic performance, attributed to its high adsorption capability. Recycling studies confirmed the sustainability of the Cu nanocomposites, maintaining over 89% degradation rate after five consecutive cycles. This research underscores the potential of green-synthesized CuNPs as efficient, stable photocatalysts for the degradation of harmful antibiotics, contributing to environmental sustainability and public health protection.

Occurrence of pharmaceutically active compounds in groundwater and their effects to the human health

Groundwater contamination by pharmaceutically active compounds (PhACs) has been considered a public health concern worldwide. Alongside the potential toxicological risk of these organic substances, many countries still rely on groundwater for drinking water supply. Thus, this study identified a priority list of seven licit PhACs, comprising acetaminophen (ACT), tramadol (TRA), carbamazepine (CBZ), erythromycin (ERY), sulfamethoxazole (SMX), metformin (MET), and oxazepam (OXZ). Consumption, concentration, and human toxicity in silico results were collected from open access databases. These three indicators were analyzed separately and grouped through a general risk index. The consumption index (data from the USA and Brazil) indicated that ACT, TRA, and MET are the most consumed. Monitoring samples from the USA and Europe (n = 816) indicated that OXZ and ERY stand out as the higher occurrence index considering both regions, but the ranking for each region showed considerable differences. When assessing toxicological risk, an index ≥ 0.5 was attributed to CBZ, MET, OXZ, SMX, and TRA. The general risk indicated the need to be attentive to MET, OXZ, and TRA as they presented ≥ 0.5 index values for at least two indicators.

Global insight into the occurrence, treatment technologies and ecological risk of emerging contaminants in sanitary sewers: Effects of the SARS-CoV-2 coronavirus pandemic

The SARS-CoV-2 pandemic caused changes in the consumption of prescribed/non-prescribed drugs and the population's habits, influencing the detection and concentration of emerging contaminants (ECs) in sanitary sewage and harming environmental and health risks. Therefore, the present work sought to discuss current literature data on the effects of the "COVID-19 pandemic factor" on the quality of raw sewage produced over a five-year period (2018-2019: pre-pandemic; 2020-2022: during the pandemic) and biological, physical, chemical and hybrid treatment technologies, influencing factors in the removal of ECs and potential ecological risks (RQs). Seven hundred thirty-one publications correlating sewage and COVID-19 were identified: 184 pre-pandemic and 547 during the pandemic. Eight classes and 37 ECs were detected in sewage between 2018 and 2022, with the "COVID-19 pandemic factor" promoting an increase in estrogens (+31,775 %), antibiotics (+19,544 %), antiepileptics and antipsychotics (+722 %), pesticides (+200 %), analgesics, anti-inflammatories and anticoagulants (+173 %), and stimulant medications (+157 %) in sanitary sewage. Among the treatment systems, aerated reactors integrated into biomembranes removed >90 % of cephalexin, clarithromycin, ibuprofen, estrone, and 17β-estradiol. The absorption, adsorption, and biodegradation mechanisms of planted wetland systems contributed to better cost-benefit in reducing the polluting load of sewage ECs in the COVID-19 pandemic, individually or integrated into the WWTP. The COVID-19 pandemic factor increased the potential ecological risks (RQs) for aquatic organisms by 40 %, with emphasis on clarithromycin and sulfamethoxazole, which changed from negligible risk and low risk to (very) high risk and caffeine with RQ > 2500. Therefore, it is possible to suggest that the COVID-19 pandemic intensified physiological, metabolic, and physical changes to different organisms in aquatic biota by ECs during 2020 and 2022.

Neurotoxic effects induced by flunitrazepam and its metabolites in zebrafish: Oxidative stress, apoptosis, and histone hypoacetylation

Benzodiazepines (BZDs) have been widely detected in aquatic environments, but their neurotoxic effects and potential mechanisms are still unclear. This study focuses on flunitrazepam (FLZ) and its metabolite, 7-aminoflunitrazepam (7-FLZ), as representative psychotropic BZD. We investigated their neurotoxic effects on adult zebrafish following a 30-day exposure to environmentally relevant concentrations. The findings reveal that exposure to these drugs induces anxiety-like and aggressive behaviors in zebrafish. Additionally, notable morphological damage to brain tissue and mitochondrial structures was observed. Through TUNEL staining, an increase in apoptotic cells was detected in the brain tissue of the exposed group, accompanied by marked elevations in ROS and caspase-3/9 levels. The upregulation of apoptosis-related genes Bax, p53, and Bcl-2 confirmed the occurrence of apoptosis. Furthermore, exposure to the drugs resulted in decreased acetylation levels of brain histones H3 and H4. The upregulation of histone deacetylation enzyme genes (HDAC1, HDAC3, HDAC4, and HDAC6) supported this result. Molecular docking results suggest that compared to 7-FLZ, FLZ has a higher binding affinity with HDAC3 and HDAC4, explaining why it causes lower histone acetylation levels. This study in zebrafish elucidates the neurotoxicity and molecular mechanisms induced by FLZ and 7-FLZ, which is significant for further understanding the impact of BZDs on human health and assessing their ecological risks.

Effects of parental exposure to amitriptyline on the survival, development, behavior, and gene expression in zebrafish offspring

In mammals, parental exposure to amitriptyline (AMI) has been proven to contribute to congenital disabilities in their offspring. However, no studies have paid attention to the adverse effects of parental exposure to amitriptyline on fish offspring. In this study, we exposed adult zebrafish (F0) to AMI (0.8 μg/L) for 21 days. Subsequently, these zebrafish (F0) were allowed to mate, and their offspring (F1) were collected to culture in clean water for 5 days. The mortality rate, average hatching time, and heart rate at 48 h post-fertilization (hpf) of F1 were investigated. Our results showed that parental exposure to AMI induced tachycardia and increased mortality in F1 zebrafish. Under a light/dark transition test, F1 larvae born from AMI-exposed parents exhibited lower locomotor activity in the dark period and decreased thigmotaxis in the light period. The transcriptome analysis showed that parental AMI exposure dysregulated some key pathways in their offspring. Through the prediction of key driver analysis, six differentially expressed genes (DEGs) were revealed as key driver genes involved in protein processing in endoplasmic reticulum (hspa5, hsp70.1, hsp90a), ribosome (rps27a) and PPAR signaling pathway (pparab and fabp2). Considering that the concentration of AMI residual components in natural water bodies may be over our test concentration (0.8 μg/L), our findings suggested that toxicity of parental exposure to the offspring of fish should receive greater attention.

Trace analysis of 47 psychotropic medications in environmental samples by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS)

Psychotropic medications are one of the most prescribed pharmaceuticals in the world. Given their frequent detection and ecotoxicity to the no-target organism, the emission of these medications into environments has gradually draw attention. The study developed a sensitive and reliable analytic method to simultaneously investigate 47 psychotropic medications in four matrices: wastewater, surface water, activated sludge, and sediment by ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS). These 47 target analytes include 24 antidepressants, 17 antianxiety drugs, 5 anticonvulsants, and 1 relevant hormone. Solid phase extraction (SPE) was employed to extract analytes from water-phase samples. Ultrasonic Solvent Extraction method with Enhanced Matrix Removal clean-up (USE-EMR) was utilized to extract target compounds from solid-phase samples, which requires more straightforward and convenient procedures than previous methods. The extraction recoveries of all analytes ranged from 80 % to 120 % in these four sample matrices. In this study, The limit of quantitation for 47 psychotropic medications were 0.15 ng/L (estazolam) to 2.27 ng/L (lorazepam), 0.08 ng/L (desvenlafaxine) to 2 ng/L (mianserin), 0.22 ng/g (dry weight, dw) (nordiazepam) to 3.65 ng/g (dw) (lorazepam), and 0.07 ng/g (dw) (carbamazepine) to 2.85 ng/g (lorazepam), in wastewater, surface water, sludge, and sediment, respectively. In addition, the developed method was employed to analyse actual samples in two wastewater treatment plants and their receiving rivers. Carbamazepine, escitalopram, clozapine, desvenlafaxine, diazepam, lamotrigine, sertraline, temazepam, and venlafaxine were nearly ubiquitous in all matrices. Moreover, this study indicated that the inadequate removal efficiencies of psychotropic medications in wastewater treatment plants (WWTPs) had resulted in a persistent discharge of these contaminants from human sources into environments.

Flunitrazepam and its metabolites compromise zebrafish nervous system functionality: An integrated microbiome, metabolome, and genomic analysis

The psychotropic drug flunitrazepam (FLZ) is frequently detected in aquatic environments, yet its neurotoxicity to aquatic organisms has not received sufficient attention. In this study, microbiome, metabolome, and genome analyses were conducted to study the effects of FLZ and its metabolite 7-aminoflunitrazepam (7-FLZ) on the zebrafish nervous system and understand their toxic mechanisms. The results demonstrated that drug exposure induced gut dysbiosis, decreased short-chain fatty acids and promoted the production of lipopolysaccharides (LPS). LPS entered the brain and interacted with Toll-like receptors to cause neuroinflammation by upregulating the expression of proinflammatory cytokines TNFα and NF-κB. The increased ratio of S-adenosylmethionine to S-adenosylhomocysteine in brain tissues indicated abnormal expression of Dnmt1 gene. Whole-genome bisulfite sequencing displayed an increase in differentially methylated regions (DMRs) associated-genes and pertinent biological pathways encompassed the MAPK signaling pathway, calcium signaling pathway, and Wnt signaling pathway. Correlation analysis confirmed connections between gut microbiota, their metabolites, inflammatory factors, and DNA methylation-related markers in brain tissue. These findings indicate that while the toxicity is somewhat reduced in metabolized products, both FLZ and 7-FLZ can induce DNA methylation in brain tissue and ultimately affect the biological function of the nervous system by disrupting gut microbiota and their metabolites.

Antidepressants in wastewater treatment plants: Occurrence, transformation and acute toxicity evaluation

Antidepressants (ATDs) are one of the most prescribed medications for psychiatric conditions. The widespread presence in aquatic environment and demonstrated ecotoxicity make ATDs a class of concerning emerging contaminants. Municipal wastewater treatment plants (WWTPs) provide important connecting channel between wastewater and aquatic environment. Herein, we present a critical overview of the occurrence, transformation and toxicity of typical ATDs during water treatments. The total concentration of the detected ATDs and their metabolites in the WWTP influents and effluents are 72.62-5011.80 ng/L and 114.48-6992.40 ng/L, respectively, on a global scale. The frequently observed negative removal of ATDs in WWTPs indicates that some ATDs exist as conjugates in wastewaters. The biotic and abiotic transformation of ATDs and the generated transformation byproducts (TPs) were identified, which occurred in WWTPs worldwide along with ATDs. Acute toxicity of ATDs and their TPs was predicated using the ECOSAR model. Compared to ATDs, the demonstrated enhanced toxicity of several TPs to aquatic organisms necessitates more attention on TPs monitoring in WWTPs. This work provides scientific support for wastewater advanced treatment to alleviate ATDs pollution in effluents.

Unraveling the combined toxicity and removal mechanisms of fluoxetine and sertraline co-contaminants by the freshwater microalga Chlorella pyrenoidosa

Selective serotonin reuptake inhibitors (SSRIs), such as fluoxetine (FLX) and sertraline (SER), are among the most widely detected pharmaceuticals in aquatic environments, and they usually occur as mixtures. However, little is known about the combined toxicity of SSRI mixtures to microalgae and the associated removal mechanisms. This study investigated the combined toxicity of FLX and SER to the growth, photosynthetic activity, and antioxidant system of Chlorella pyrenoidosa and their removal mechanisms. The results showed that FLX and SER strongly inhibited microalgal growth with 96 h EC50 values of 493 and 61.1 μg/L, respectively. Additionally, the combined toxicity of FLX and SER towards microalgal growth exhibited an additive effect. After 4 days of short-term exposure, FLX, SER, and their mixtures caused photosynthetic damage and oxidative stress in microalgae, and the mixture's toxicity was stronger than those of individuals. However, the adverse effects on microalgal growth, photosynthetic activity, and antioxidant system were alleviated with increasing exposure time. Meanwhile, C. pyrenoidosa efficiently removed FLX (67.59%-99.08%) and SER (94.92%-99.11%) individually after 11 days of cultivation. Biodegradation (59.25%-86.21%) was the prominent removal mechanism of FLX, while both biodegradation (48.08%-88.17%) and bioaccumulation (4.74%-43.38%) contributed significantly to SER removal. The co-existence of FLX and SER lowered the removal rate and biodegradation amount of both compounds. Besides, SER inhibited C. pyrenoidosa's N-demethylation and O-dealkylation of FLX, while co-existing with FLX inhibited the excretion of the N-deamination product of SER from microalgal cells. Furthermore, the principal component analysis indicated that the removal performance of FLX, SER, and their mixtures correlated strongly to the microalgae's physiological and biochemical states. These results highlighted the significance of co-contamination during ecological risk assessments and microalgae-based bioremediation of SSRIs.

In five wastewater treatment plants in Xinjiang, China: Removal processes for illicit drugs, their occurrence in receiving river waters, and ecological risk assessment

Residues of illicit drugs are frequently detected in wastewater, but data on their removal efficiency by wastewater treatment plants (WWTPs) and the ecological risks to the aquatic environment are lacking in this study. The research evaluates the residues, mass load, drug removal efficiency, and risk assessment of illicit drugs in WWTPs and aquatic environments (lakes) in Xinjiang, China. Initially, the concentration (incidence) and mass load of 10 selected illicit drugs were analyzed through wastewater analysis. The detected substances included methamphetamine (METH), morphine (MOR), 3,4-methylenedioxy methamphetamine (MDMA), methadone (MTD), cocaine (COC), benzoylecgonine (BE), ketamine (KET), and codeine (COD), with concentrations ranging from 0.11 ± 0.01 ng/L (methadone) to 48.26 ± 25.05 ng/L (morphine). Notably, morphine (59.74 ± 5.82 g/day) and methamphetamine (41.81 ± 4.91 g/day) contributed significantly to the WWTPs. Next, the drug removal efficiency by different sewage treatment processes was ranked as follows: Anaerobic-Oxic (A/O) combined Membrane Bio-Reactor (MBR) treatment process > Oxidation ditch treatment process > Anaerobic-Anoxic-Oxic (A2/O) treatment process > Anaerobic-Anoxic-Oxic combined Membrane Bio-Reactor treatment process. Finally, the research reviewed the concentration and toxicity assessments of these substances in the aquatic environment (lakes). The results indicated that Lake1 presented a medium risk level concerning the impact of illicit drugs on the aquatic environment, whereas the other lakes exhibited a low risk level. As a result, it is recommended to conduct long-term monitoring and source analysis of illicit drugs, specifically in Lake1, for further investigation. In conclusion, to enhance the understanding of the effects of illicit drugs on the environment, future research should expand the list of target analytes.

Multi-level toxicity assessment of the antidepressant venlafaxine in embryos/larvae and adults of zebrafish (Danio rerio)

The toxic effects of venlafaxine (VLX) on aquatic organisms have already been verified and therefore are a proven matter of concern. Herein, we evaluated zebrafish embryos/adults after acute exposure to VLX. Embryos/larvae were exposed to different concentrations of VLX (100-1000 mg/L; 1.33 as a dilution factor), to evaluate mortality/developmental changos and to analyze biomarkers (0.002-100 mg/L). For adults, mortality, genotoxicity, and biomarkers were assessed in five different concentrations of VLX (1-100 mg/L). The median lethal concentration (LC50-168h) was 274.1 mg/L for embryos/larvae, and >100 mg/L for adults (LC50-96h). VLX decreased the heart rate frequency and caused premature hatching and lack of equilibrium in embryos/larvae exposed to different concentrations ranging from 100 to 562.5 mg/L. The activity of acetylcholinesterase (AChE) was inhibited in larvae exposed to 1, 25 and 100 mg/L. Glutathione-S-transferase (GST) activity was reduced in both larvae and adults after exposure to different concentrations, mainly at 25 mg/L. For both larvae and adults, lactate dehydrogenase (LDH) activity increased after 100 mg/L of VLX exposure. No DNA damage was observed in peripheral erythrocytes. Exposure to VLX may cause adverse effects on zebrafish in their early and adult life stages, interfering with embryo-larval development, and can induce physiological disturbances in adults.

Assessment of the Presence of Transformation Products of Certain Pharmaceutical Products (Psychotropic Family) by Suspect and Non-Targeted HRMS Screening in Wastewater Treatment Plants

Aquatic environments are the final receptors of human emissions and are therefore contaminated by molecules, such as pharmaceuticals. After use, these compounds and their metabolites are discharged to wastewater treatment plants (WWTPs). During wastewater treatment, compounds may be eliminated or degraded into transformation products (TPs) or may be persistent. The aim of this study was to develop an analytical method based on high resolution mass spectrometry (HRMS) for the identification of six psychotropic drugs that are widely consumed in France and present in WWTPs, as well as their potential associated metabolites and TPs. Four out of six psychotropic drugs and between twenty-five and thirty-seven potential TPs were detected in wastewater, although this was based on full scan data. TPs not reported in the literature and specific to the study sites and therefore to the wastewater treatment processes were tentatively identified. For the selected drugs, most known and present TPs were identified, such as desmethylvenlafaxine or norcitalopram. Moreover, the short fragmentation study led rather to the identification of several TPs of carbamazepine as ubiquitous persistent TPs.

Ligninolytic enzyme activity and removal efficiency of pharmaceuticals in a water matrix by fungus Rhizopus sp. Isolated from cassava

Residual amounts of pharmaceutical compounds (PhCs) and by-products are continually released into surface water with effluents from conventional wastewater treatment plants (WWTPs). This study evaluated the ability of fungal isolate to remove selected PhCs [carbamazepine (CBZ), diclofenac (DCF) and ibuprofen (IBP)] from wastewater. The fungus used was Rhizopus sp. which was isolated from tuberous roots of cassava (Manihot esculenta). The isolate exhibited an important removal efficiency up to 100% and this was linked to ligninolytic enzymatic activity for lignin peroxidase (15.29 ± 2.69U/L) and manganese peroxidase (85.22 ± 4.26U/L), except laccase. This activity was optimum on day 9 of treatment. PhC metabolites were identified during the experiment revealing the existence of a biotransformation process catalysed by the isolated fungus. The disappearance of PhCs was attributed to their biosorption and biotransformation. However, it was not possible to establish a relationship between the ligninolytic enzymatic activity and the removal efficiency, which leads to the conclusion that there are other fungal metabolites which also play an important role in the biotransformation and biodegradation of the selected PhCs.

The presence of antibiotics and multidrug-resistant Staphylococcus aureus reservoir in a low-order stream spring in central Brazil

The disposal of industrial effluents strongly influences low-order streams, which makes them fragile ecosystems that can be impacted by contamination. In central Brazil, the Extrema River spring targets the dumping of pharmaceutical products from the surrounding industries. So, this work aimed to investigate the presence of antibiotics in Extrema River spring samples and the isolation of Staphylococcus aureus, a potential multidrug-resistant bacteria, verifying the antimicrobial resistance profile of these isolates. Three campaigns were carried out in different locals (P1-P3) between October and December 2021, in the dry and rainy seasons. The high-performance liquid chromatography-tandem mass spectrometry (LCMS) approach indicated the presence of sulfamethoxazole (≥ 1 ng/L), metronidazole (< 0.5 ng/L), and chloramphenicol (< 5 ng/L) in the water samples in November (rainy season). S. aureus was isolated in P1 (n = 128), P2 (n = 168), and P3 (n = 36), with greater resistance to trimethoprim-sulfamethoxazole (90%), clindamycin (70%), and gentamicin (60%). The presence of antibiotics in the Extrema River spring may cause S. aureus antibiotic resistance development. The presence of antibiotics and the high percentage of isolated multidrug-resistant S. aureus in the Extrema River spring cause concern and indicate the clandestine dumping of effluents from nearby pharmaceutical industries. Since preserving the springs of low-order streams is important for the environment and public health, we encourage monitoring the wastewater from Extrema River's nearby pharmaceutical industries and preserving the spring of this river.

A review of hybrid enzymatic-chemical treatment for wastewater containing antiepileptic drugs

Epilepsy is one of the most common neurological diseases worldwide and requires treatment with antiepileptic drugs for many years or for life. This fact leads to the need for constant production and use of these compounds, placing them among the four pharmaceutical classes most found in wastewater. Even at low concentrations, antiepileptics pose risks to human and environmental health and are considered organic contaminants of emerging concern. Conventional treatments have shown low removal of these drugs, requiring advanced and innovative approaches. In this context, this review covers the results and perspectives on (1) consumption and occurrence of antiepileptics in water, (2) toxicological effects in aquatic ecosystems, (3) enzymatic and advanced oxidation processes for degrading antiepileptics drugs from a molecular point of view (biochemical and chemical phenomena), (4) improvements in treatment efficiency by hybridization, and (5) technical aspects of the enzymatic-AOP reactors.

Hazard and health risk assessment of exposure to pharmaceutical active compounds via toxicological evaluation by zebrafish

The uncontrolled or continuous release of effluents from wastewater treatment plants leads to the omnipresence of pharmaceutical active compounds (PhACs) in the aquatic media. Today, this is a confirmed problem becoming a main subject of twin public and scientific concerns. However, still little information is available about the long-term impacts of these PhACs on aquatic organisms. In this review, efforts were made to reveal correlation between the occurrence in the environment, ecotoxicological and health risks of different PhACs via toxicological evaluation by zebrafish (Danio rerio). This animal model served as a bioindicator for any health impacts after the exposure to these contaminants and to better understand the responses in relation to human diseases. This review paper focused on the calculation of Risk Quotients (RQs) of 34 PhACs based on environmental and ecotoxicological data available in the literature and prediction from the ECOSAR V2.2 software. To the best of the authors' knowledge, this is the first report on the risk assessment of PhACs by the two different methods as mentioned above. RQs showed greater difference in potential environmental risks of the PhACs. These differences in risk values underline the importance of environmental and experimental factors in exposure conditions and the interpretation of RQ values. While the results showed high risk to Danio rerio of the majority of PhACs, risk qualification of the others varied between moderate to insignifiant. Further research is needed to assess pharmaceutical hazards when present in wastewater before discharge and monitor the effectiveness of treatment processes. The recent new advances in the morphological assessment of toxicant-exposed zebrafish larvae for the determination of test compounds effects on the developmental endpoints were also discussed. This review emphasizes the need for strict regulations on the release of PhACs into environmental media in order to minimize their toxicity to aquatic organisms.

Insight into pharmaceutical and personal care products removal using constructed wetlands: A comprehensive review

Pharmaceutical and personal care products (PPCPs) were regarded as emerging environmental pollutants due to their ubiquitous appearance and high environmental risks. The wastewater treatment plants (WWTPs) became the hub of PPCPs receiving major sources of PPCPs used by humans. Increasing concern has been focused on promoting cost-effective ways to eliminate PPCPs within WWTPs for blocking their route into the environment through effluent discharging. Among all advanced technologies, constructed wetlands (CWs) with a combination of plants, substrates, and microbes attracted attention due to their cost-effectiveness and easier maintenance during long-term operation. This study offers baseline data for risk control and future treatment by discussing the extent and dispersion of PPCPs in surface waters over the past ten years and identifying the mechanisms of PPCPs removal in CWs based on the up-to-present research, with a special focus on the contribution of sediments, vegetation, and the interactions of microorganisms. The significant role of wetland plants in the removal of PPCPs was detailed discussed in identifying the contribution of direct uptake, adsorption, phytovolatilization, and biodegradation. Meanwhile, the correlation between the physical-chemical characteristics of PPCPs, the configuration operation of wetlands, as well as the environmental conditions with PPCP removal were also further estimated. Finally, the critical issues and knowledge gaps before the real application were addressed followed by promoted future works, which are expected to provide a comprehensive foundation for study on PPCPs elimination utilizing CWs and drive to achieve large-scale applications to treat PPCPs-contaminated surface waters.

Biological-Activity-Based Prioritization of Antidepressants in Wastewater in England and Japan

Antidepressants are one of the most commonly prescribed pharmaceuticals. Although they have been frequently detected in aquatic environments around the globe, little is known regarding their adverse effects on humans and aquatic organisms. Recently, an in vitro monoamine transporter inhibition assay was developed to detect transporter-inhibitory activities of antidepressants in wastewater in Japan. However, it was unclear which antidepressants were responsible for transporter-inhibitory activities in wastewater. Herein, the per capita consumption of 32 antidepressants, their excretion of unchanged parent compounds, per capita water consumption, removal rate during wastewater treatment processes, and potency values from the monoamine transporter inhibition assay were used to prioritize antidepressants of concern in effluent wastewater in England and Japan. In both countries, sertraline and O-desmethylvenlafaxine had the highest contribution to inhibitory activities against the human serotonin transporter (hSERT) and zebrafish SERT (zSERT), respectively. It was found that the antidepressants inhibited the zSERT more strongly than the hSERT. The inhibitory activities found against the zSERT in wastewater in England and Japan were higher than thresholds for abnormal behavior in fish. The antidepressants prioritized in this study provide insight into launching environmental monitoring and ecotoxicological studies of antidepressants.

Evaluating the spatial and temporal distribution of emerging contaminants in the Pearl River Basin for regulating purposes

Little information is available on how the types, concentrations, and distribution of chemicals have evolved over the years. The objective of the present study is therefore to review the spatial and temporal distribution profile of emerging contaminants with limited toxicology data in the pearl river basin over the years to build up the emerging contaminants database in this region for risk assessment and regulatory purposes. The result revealed that seven groups of emerging contaminants were abundant in this region, and many emerging contaminants had been detected at much higher concentrations before 2011. Specifically, antibiotics, phenolic compounds, and acidic pharmaceuticals were the most abundant emerging contaminants detected in the aquatic compartment, while phenolic compounds were of the most profound concern in soil. Flame retardants and plastics were the most frequently studied chemicals in organisms. The abundance of the field concentrations and frequencies varied considerably over the years, and currently available data can hardly be used for regulation purposes. It is suggested that watershed management should establish a regular monitoring scheme and comprehensive database to monitor the distribution of emerging contaminants considering the highly condensed population in this region. The priority monitoring list should be formed in consideration of historical abundance, potential toxic effects of emerging contaminants as well as the distribution of heavily polluting industries in the region.

A Current Review of Water Pollutants in American Continent: Trends and Perspectives in Detection, Health Risks, and Treatment Technologies

Currently, water pollution represents a serious environmental threat, causing an impact not only to fauna and flora but also to human health. Among these pollutants, inorganic and organic pollutants are predominantly important representing high toxicity and persistence and being difficult to treat using current methodologies. For this reason, several research groups are searching for strategies to detect and remedy contaminated water bodies and effluents. Due to the above, a current review of the state of the situation has been carried out. The results obtained show that in the American continent a high diversity of contaminants is present in the water bodies affecting several aspects, in which in some cases, there exists alternatives to realize the remediation of contaminated water. It is concluded that the actual challenge is to establish sanitation measures at the local level based on the specific needs of the geographical area of interest. Therefore, water treatment plants must be designed according to the contaminants present in the water of the region and tailored to the needs of the population of interest.

Investigation on consumption of psychoactive substances and their ecological risks using wastewater-based epidemiology: a case study on Qinghai-Tibet Plateau

The Qinghai-Tibet Plateau is the third pole of the world, and information on the consumption of psychoactive substances (PSs) in this area is scarce. In this study, we selected Qinghai Province as the research area, and the per capita consumption and prevalence of PSs were investigated using wastewater-based epidemiology. Samples from 17 wastewater treatment plants (WWTPs) in 5 major cities in Qinghai Province were monitored, and 11 PSs were detected by ultra-high performance liquid chromatography-tandem mass spectrometry. Results showed that the target compounds were detected in all samples, with relatively high concentrations of ephedrine (2.1-4825.3 ng/L) and methamphetamine (1.5-295.7 ng/L). The consumption of methamphetamine in Xining City, Haidong City, and Haixi City was up to 78.4, 16.8, and 21.2 mg/1000 inh/d (the PS consumption per 1000 inhabitants in 1 day), respectively, higher than that in the other two cities, which was the result of the different consumption patterns and its relationship with the economic levels of each city. High consumption of methadone (47.9 mg/1000 inh/day) was found in Xining City, which might be related to the methadone maintenance therapy sites in the city. Methamphetamine was the most prevalent drug, with the prevalence ranging from 0.003 (Guoluo) to 0.197% (Xining), and the prevalence of other PSs was low. The ecological risk assessment of PSs in the effluent of WWTPs showed that methadone exerted a low risk to aquatic organisms in three sites, while other substances posed potential risk or no risk. However, the long-term effect of PSs cannot be ignored.

Neuroactive pharmaceuticals in estuaries: Occurrence and tissue-specific bioaccumulation in multiple fish species

Contamination of surface waters by pharmaceuticals is an emerging problem globally. This is because the increased access and use of pharmaceuticals by a growing world population lead to environmental contamination, threatening non-target species in their natural environment. Of particular concern are neuroactive pharmaceuticals, which are known to bioaccumulate in fish and impact a variety of individual processes such as fish reproduction or behaviour, which can have ecological impacts and compromise fish populations. In this work, we investigate the occurrence and bioaccumulation of 33 neuroactive pharmaceuticals in brain, muscle and liver tissues of multiple fish species collected in four different estuaries (Douro, Tejo, Sado and Mira). In total, 28 neuroactive pharmaceuticals were detected in water and 13 in fish tissues, with individual pharmaceuticals reaching maximum concentrations of 1590 ng/L and 207 ng/g ww, respectively. The neuroactive pharmaceuticals with the highest levels and highest frequency of detection in the water samples were psychostimulants, antidepressants, opioids and anxiolytics, whereas in fish tissues, antiepileptics, psychostimulants, anxiolytics and antidepressants showed highest concentrations. Bioaccumulation was ubiquitous, occurring in all seven estuarine and marine fish species. Notably, neuroactive compounds were detected in every water and fish brain samples, and in 95% of fish liver and muscle tissues. Despite variations in pharmaceutical occurrence among estuaries, bioaccumulation patterns were consistent among estuarine systems, with generally higher bioaccumulation in fish brain followed by liver and muscle. Moreover, no link between bioaccumulation and compounds' lipophilicity, species habitat use patterns or trophic levels was observed. Overall, this work highlights the occurrence of a highly diverse suite of neuroactive pharmaceuticals and their pervasiveness in waters and fish from estuarine systems with contrasting hydromorphology and urban development and emphasizes the urgent need for toxicity assessment of these compounds in natural ecosystems, linked to internalized body concentration in non-target species.

Bioaccumulation potential of the tricyclic antidepressant amitriptyline in a marine Polychaete, Nereis virens

The continual discharge of pharmaceuticals from wastewater treatment plants (WWTPs) into the marine environment, even at concentrations as low as ng/L, can exceed levels that induce sublethal effects to aquatic organisms. Amitriptyline, a tricyclic antidepressant, is the most prescribed antidepressant in Norway, though the presence, potential for transport, and uptake by aquatic biota have not been assessed. To better understand the release and bioaccumulative capacity of amitriptyline, laboratory exposure studies were carried out with field-collected sediments. Influent and effluent composite samples from the WWTP of Stavanger (the 4th largest city in Norway) were taken, and sediment samples were collected in three sites in the proximity of this WWTP discharge at sea (WWTP discharge (IVAR), Boknafjord, and Kvitsøy (reference)). Polychaetes (Nereis virens) were exposed to field-collected sediments, as well as to Kvitsøy sediment spiked with 3 and 30 μg/g amitriptyline for 28 days. The WWTP influent and effluent samples had concentrations of amitriptyline of 4.93 ± 1.40 and 6.24 ± 1.39 ng/L, respectively. Sediment samples collected from IVAR, Boknafjord, and Kvitsøy had concentrations of 6.5 ± 3.9, 15.6 ± 12.7, and 12.7 ± 8.0 ng/g, respectively. Concentrations of amitriptyline were below the limit of detection in polychaetes exposed to sediment collected from Kvitsøy and IVAR, and 5.2 ± 2.8 ng/g in those exposed to Boknafjord sediment. Sediment spiked with 3 and 30 μg/g amitriptyline had measured values of 423.83 ± 33.1 and 763.2 ± 180.5 ng/g, respectively. Concentrations in worms exposed to the amended sediments were 9.5 ± 0.2 and 56.6 ± 2.2 ng/g, respectively. This is the first known study to detect measurable concentrations of amitriptyline in WWTP discharge in Norway and accumulation in polychaetes treated with field-collected sediments, suggesting that amitriptyline has the potential for trophic transfer in marine systems.

Effects of the Antidepressant Amitriptyline on Juvenile Brown Trout and Their Modulation by Microplastics

Pharmaceuticals such as antidepressants are designed to be bioactive at low concentrations. According to their mode of action, they can also influence non-target organisms due to the phylogenetic conservation of molecular targets. In addition to the pollution by environmental chemicals, the topic of microplastics (MP) in the aquatic environment came into the focus of scientific and public interest. The aim of the present study was to investigate the influence of the antidepressant amitriptyline in the presence and absence of irregularly shaped polystyrene MP as well as the effects of MP alone on juvenile brown trout (Salmo trutta f. fario). Fish were exposed to different concentrations of amitriptyline (nominal concentrations between 1 and 1000 µg/L) and two concentrations of MP (104 and 105 particles/L; <50 µm) for three weeks. Tissue cortisol concentration, oxidative stress, and the activity of two carboxylesterases and of acetylcholinesterase were assessed. Furthermore, the swimming behavior was analyzed in situations with different stress levels. Exposure to amitriptyline altered the behavior and increased the activity of acetylcholinesterase. Moreover, nominal amitriptyline concentrations above 300 µg/L caused severe acute adverse effects in fish. MP alone did not affect any of the investigated endpoints. Co-exposure caused largely similar effects such as the exposure to solely amitriptyline. However, the effect of amitriptyline on the swimming behavior during the experiment was alleviated by the higher MP concentration.

Legacy and emerging pollutants in Latin America: A critical review of occurrence and levels in environmental and food samples

The increase and indiscriminate use of personal care products, food products, fertilizers, pesticides, and health products, among others, have resulted/are resulting in extensive environmental contamination. Most of these products contain traces of widespread chemicals, usually known as emerging pollutants (EPs) or pollutants of emerging concern (PEC). The Latin American (LA) region comprises 20 countries with different social and cultural aspects, with 81 % of the population living in urban areas. The LA region has some countries on the top list of users/consumers of EPs, from pesticides and fertilizers to personal care products. However, there is a gap in information related to the distribution of EPs in the environment of this region, with very few existing review texts exploring this issue. Therefore, this present paper advances this approach. An exhaustive literature review, with the selection of 176 documents, provided unique up-to-date information on the presence/distribution of 17 classes of legacy or emerging pollutants in different food and environmental matrices (soil, sediment, water, and air). The study shows that the wide distribution and recorded levels of these pollutants in the continental environment are potential risks to human health, mainly through food and drinking water ingestion. Polycyclic aromatic hydrocarbons are pollutants of deep public concern since they show carcinogenic properties. Several classes of pollutants, like endocrine disruptors, have caused harmful effects on humans and the environment. Besides that, pharmaceutical products and pesticides are compounds of high consumption worldwide, being environmental contamination a real and ongoing possibility. Finally, gaps and future research needs are deeply pointed out.

Identification of Photodegradation Products of Escitalopram in Surface Water by HPLC-MS/MS and Preliminary Characterization of Their Potential Impact on the Environment

The study concerns the photodegradation of the antidepressant escitalopram (ESC), the S-enantiomer of the citalopram raceme, both in ultrapure and surface water, considering the contribution of indirect photolysis through the presence of nitrate and bicarbonate. The effect of nitrate and bicarbonate concentrations was investigated by full factorial design, and only the nitrate concentration resulted in having a significant effect on the degradation. The kinetics of ESC photodegradation is the pseudo-first-order (half-life = 62.4 h in ultrapure water and 48.4 h in lake water). The generation of transformation products (TPs) was monitored through a developed and validated HPLC-MS/MS method. Fourteen TPs were identified in ultrapure water (one of them, at m/z 261, for the first time) and other two TPs at m/z 327 (found for the first time in this study) were identified only in presence of a nitrate. Several TPs were the same as those formed during the photodegradation of citalopram. The photodegradation pathway of ESC and its mechanism of degradation in water is proposed. The method was applied successfully to the analyses of surface water samples, in which a few dozen of ng L−1 of ESC was determined together with the presence of TP2, TP5 and TP12. Finally, a preliminary in silico evaluation of the toxicological profile and environmental behavior of TPs by computational models was carried out; two TPs (TP4 and TP10) were identified as of potential concern, as they were predicted mutagenic by Ames test model.

Ultraviolet oxidative degradation of typical antidepressants: Pathway, product toxicity, and DFT theoretical calculation

The ubiquity of antidepressants in the environment has posed a potential threat to eco-systematic safety. In this study, six kinds of antidepressants including fluoxetine (FLU), paroxetine (PAR), sertraline (SER), fluvoxamine (FLX), citalopram (CTP), and venlafaxine (VEN) were selected to explore their degrading kinetics, transformation pathways, and the acute toxicity of the reaction solution during UV oxidation. The results showed that the order of the photodegradation rate was FLU > PAR > SER > CTP > FLX > VEN. The calculation results of density functional theory (DFT) and molecular orbital theory showed that it was positively correlated with the frontier electron density of drugs and negatively correlated with the HOMO-LUMO gap, respectively. Intermediates were identified with UHPLC-Q-TOF/MS/MS to propose the possible degradation pathways of the drugs and the most likely directions of the reactions were determined by the single point energy calculation. The results of toxicity tests indicated that the acute toxicity of the reaction solution of PAR did not change significantly. The photolysates toxicity of FLU, SER, and FLX decreased at the end of the reaction, while that of CTP and VEN was increased by 1.5 and 1.3 times compared with the parent compound, respectively. Toxicity predictions by the quantitative structure activity relationship (QSAR) model showed that except FLU-162, FLX-174, and VEN-230, other degradation products have developmental toxicity. The results revealed the transformation pathways of these drugs under the UV disinfection process in wastewater treatment plants, especially the formation of toxic by-products during the disinfection process.

Occurrence, distribution and risk of pharmaceutical and personal care products in the Haihe River sediments, China

In the aquatic environment, pharmaceuticals and personal care products (PPCPs) detected in sediments are rising health concerns to human and aquatic ecosystem. The migration of PPCPs in the sediments poses a potential risk to surface water and groundwater environment. Insight on the spatial distribution and vertical profile of PPCPs in sediments at the regional scale is valuable for comprehensive prevention of PPCP risk. The Haihe River is one of the major water systems for the rapid development of urbanization, industrialization and agriculture in Northern China. The study aimed to characterize the occurrence, distribution and ecological risks of PPCPs in the sediments of the Haihe River, especially to investigate the vertical distribution of PPCPs using core sediments. High performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was used to analyze 24 selected PPCPs in sediment samples. In total, 11 PPCPs were detected, and the detected concentrations (0-1.26 ng g^-1) were, lower than in other water bodies in literature (0-24.4 ng g^-1). The sediments of the Haihe River located in the Tianjin downtown were most-severely polluted, with the highest cumulative concentration of PPCPs of 9.45 ng g^-1, indicating the relatively high contribution of human consumption of PPCPs for the megacity. Spearman correlation analysis shows that both of the TOC contents and particle size distribution can influence the migration and deposition of PPCPs. The risk assessment results showed that the current level of PPCPs has no severe adverse effects on aquatic organisms in the Haihe River. However, special attention should be paid to the environmental risks caused by the migration of PPCPs with high loading and mobility (such as sulfamethoxazole).