Presence of pharmaceuticals in benthic fauna living in a small stream affected by effluent from a municipal sewage treatment plant

Effect of ph on migration patterns and degradation pathways of sulfamethazine in soil systems

Sulfonamide antibiotics (SAs) are widely used antimicrobial agents in livestock and aquaculture, and most of them entering the animal's body will be released into the environment as prodrugs or metabolites, which ultimately affect human health through the food chain. Both acid deposition and salinization of soil may have an impact on the migration and degradation of antibiotics. Sulfamethazine (SM2), a frequently detected compound in agricultural soils, has a migration and transformation process in the environment that is closely dependent on environmental pH. Nevertheless, scarcely any studies have been conducted on the effect of soil pH changes on the environmental behavior of sulfamethazine. We analyzed the migration and degradation mechanisms of SM2 using simulation experiments and ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) techniques. The results showed that acidic conditions limited the vertical migration of sulfadimidine, and SM2 underwent different reaction processes under different pH conditions, including S-C bond breaking, S-N bond hydrolysis, demethylation, six-membered heterocyclic addition, methyl hydroxylation and ring opening. The study of the migration pattern and degradation mechanism of SM2 under different pH conditions can provide a solid theoretical basis for assessing the pollution risk of sulfamethazine degradation products under acid rain and saline conditions, and provide a guideline for remediation of antibiotic contamination, so as to better prevent, control and protect groundwater resources.

Developing an Approach for Integrating Chemical Analysis and Transcriptional Changes to Assess Contaminants in Water, Sediment, and Fish

Pharmaceuticals in aquatic environments pose threats to aquatic organisms because of their continuous release and potential accumulation. Monitoring methods for these contaminants are inadequate, with targeted analyses falling short in assessing water quality's impact on biota. The present study advocates for integrated strategies combining suspect and targeted chemical analyses with molecular biomarker approaches to better understand the risks posed by complex chemical mixtures to nontarget organisms. The research aimed to integrate chemical analysis and transcriptome changes in fathead minnows to prioritize contaminants, assess their effects, and apply this strategy in Wascana Creek, Canada. Analysis revealed higher pharmaceutical concentrations downstream of a wastewater-treatment plant, with clozapine being the most abundant in fathead minnows, showing notable bioavailability from water and sediment sources. Considering the importance of bioaccumulation factor and biota-sediment accumulation factor in risk assessment, these coefficients were calculated based on field data collected during spring, summer, and fall seasons in 2021. Bioaccumulation was classified as very bioaccumulative with values >5000 L kg-1, suggesting the ability of pharmaceuticals to accumulate in aquatic organisms. The study highlighted the intricate relationship between nutrient availability, water quality, and key pathways affected by pharmaceuticals, personal care products, and rubber components. Prioritization of these chemicals was done through suspect analysis, supported by identifying perturbed pathways (specifically signaling and cellular processes) using transcriptomic analysis in exposed fish. This strategy not only aids in environmental risk assessment but also serves as a practical model for other watersheds, streamlining risk-assessment processes to identify environmental hazards and work toward reducing risks from contaminants of emerging concern. Environ Toxicol Chem 2024;00:1-22. © 2024 SETAC.

The effect of warming and seasonality on bioaccumulation of selected pharmaceuticals in freshwater invertebrates

Multiple human-induced environmental stressors significantly threaten global biodiversity and ecosystem functioning. Climate warming and chemical pollution are two widespread stressors whose impact on freshwaters is likely to increase. However, little is known about the combined effects of warming on the bioaccumulation of environmentally relevant mixtures of emerging contaminants, such as pharmaceutically active compounds (PhACs) in freshwater biota. This study investigated the bioaccumulation of a mixture of 15 selected PhACs at environmentally relevant concentrations in common freshwater macroinvertebrate taxa, exposed to ambient temperatures and warming (+4 °C) during the warm and cold seasons in two outdoor mesocosm experiments. Nine PhACs (carbamazepine, cetirizine, clarithromycin, clindamycin, fexofenadine, telmisartan, trimethoprim, valsartan and venlafaxine) were dissipated faster in the warm season experiment than in the cold season experiment, while lamotrigine showed the opposite trend. The most bioaccumulated PhACs in macroinvertebrates were tramadol, carbamazepine, telmisartan, venlafaxine, citalopram and cetirizine. The bioaccumulation was taxon, season and temperature dependent, but differences could not be fully explained by the different water stability of the PhACs and their partitioning between water and leaf litter. The highest water-based bioaccumulation factors were found in Asellus and Planorbarius. Moreover, the bioaccumulation of some PhACs increased with warming in Planorbarius, suggesting that it could be used as a sentinel taxon in environmental studies of the effects of climate warming on PhAC bioaccumulation.

Health of wild fish exposed to contaminants of emerging concern in freshwater ecosystems utilized by a Minnesota Tribal community

Fish serve as indicators of exposure to contaminants of emerging concern (CECs)-chemicals such as pharmaceuticals, hormones, and personal care products-which are often designed to impact vertebrates. To investigate fish health and CECs in situ, we evaluated the health of wild fish exposed to CECs in waterbodies across northeastern Minnesota with varying anthropogenic pressures and CEC exposures: waterbodies with no human development along their shorelines, those with development, and those directly receiving treated wastewater effluent. Then, we compared three approaches to evaluate the health of fish exposed to CECs in their natural environment: a refined fish health assessment index, a histopathological index, and high-throughput (ToxCast) in vitro assays. Lastly, we mapped adverse outcome pathways (AOPs) associated with identified ToxCast assays to determine potential impacts across levels of biological organization within the aquatic system. These approaches were applied to subsistence fish collected from the Grand Portage Indian Reservation and 1854 Ceded Territory in 2017 and 2019. Overall, 24 CECs were detected in fish tissues, with all but one of the sites having at least one detection. The combined implementation of these tools revealed that subsistence fish exposed to CECs had histological and macroscopic tissue and organ abnormalities, although a direct causal link could not be established. The health of fish in undeveloped sites was as poor, or sometimes poorer, than fish in developed and wastewater effluent-impacted sites based on gross and histologic tissue lesions. Adverse outcome pathways revealed potential hazardous pathways of individual CECs to fish. A better understanding of how the health of wild fish harvested for consumption is affected by CECs may help prioritize risk management research efforts and can ultimately be used to guide fishery management and public health decisions. Integr Environ Assess Manag 2024;20:846-863. © 2023 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Changes in Induced-Antipredation Defense Traits and Transcriptome Regulations of Daphnia magna in Response to 5-HT1A Receptor Antagonist

The serotonin signaling system plays a crucial role in regulating the ontogeny of crustaceans. Here, we describe the effects of different concentrations of the 5-hydroxytryptamine 1A receptor antagonist (WAY-100635) on the induced antipredation (Rhodeus ocellatus as the predator), morphological, behavioral, and life-history defenses of Daphnia magna and use transcriptomics to analyze the underlying molecular mechanisms. Our results indicate that exposure to WAY-100635 leads to changes in the expression of different defensive traits in D. magna when faced with fish predation risks. Specifically, as the length of exposure to WAY-100635 increases, high concentrations of WAY-100635 inhibit defensive responses associated with morphological and reproductive activities but promote the immediate negative phototactic behavioral defense of D. magna. This change is related to the underlying mechanism through which WAY-100635 interferes with gene expression of G-protein-coupled GABA receptors by affecting GABBR1 but promotes serotonin receptor signaling and ecdysteroid signaling pathways. In addition, we also find for the first time that fish kairomone can significantly activate the HIF-1α signaling pathway, which may lead to an increase in the rate of immediate movement. These results can help assess the potential impacts of serotonin-disrupting psychotropic drugs on zooplankton in aquatic ecosystems.

Long-term dietary exposure to the non-steroidal anti-inflammatory drugs diclofenac and ibuprofen can affect the physiology of common carp (Cyprinus carpio) on multiple levels, even at "environmentally relevant" concentrations

The aim of the study was to evaluate the effects of emerging environmental contaminants, the non-steroidal anti-inflammatory drugs (NSAIDs) diclofenac (DCF) and ibuprofen (IBP), on physiological functions in juvenile common carp (Cyprinus carpio). Fish were exposed for 6 weeks, and for the first time, NSAIDs were administered through diet. Either substance was tested at two concentrations, 20 or 2000 μg/kg, resulting in four different treatments (DCF 20, DCF 2000, IBP 20, IBP 2000). The effects on haematological and biochemical profiles, the biomarkers of oxidative stress, and endocrine disruption were studied, and changes in RNA transcription were also monitored to obtain a comprehensive picture of toxicity. Fish exposure to high concentrations of NSAIDs (DCF 2000, IBP 2000) elicited numerous statistically significant changes (p < 0.05) in the endpoints investigated, with DCF being almost always more efficient than IBP. Compared to control fish, a decrease in total leukocyte count attributed to relative lymphopenia was observed. Plasma concentrations of total proteins, ammonia, and thyroxine, and enzyme activities of alanine aminotransferase (ALT), aspartate aminotransferase, and alkaline phosphatase (ALP) were significantly elevated in either group, as were the activities of certain hepatic antioxidant enzymes (superoxide dismutase, glutathione-S-transferase) in the DCF 2000 group. The transcriptomic profile of selected genes in the tissues of exposed fish was affected as well. Significant changes in plasma total proteins, ammonia, ALT, and ALP, as well as in the transcription of genes related to thyroid function and the antioxidant defense of the organism, were found even in fish exposed to the lower DCF concentration (DCF 20). As it was chosen to match DCF concentrations commonly detected in aquatic invertebrates (i.e., the potential feed source of fish), it can be considered "environmentally relevant". Future research is necessary to shed more light on the dietary NSAID toxicity to fish.

Antifungal drugs in the aquatic environment: A review on sources, occurrence, toxicity, health effects, removal strategies and future challenges

Fungal infections pose a significant global health burden, resulting in millions of severe cases and deaths annually. The escalating demand for effective antifungal treatments has led to a rise in the wholesale distribution of antifungal drugs, which consequently has led to their release into the environment, posing a threat to ecosystems and human health. This article aims to provide a comprehensive review of the presence and distribution of antifungal drugs in the environment, evaluate their potential ecological and health risks, and assess current methods for their removal. Reviewed studies from 2010 to 2023 period have revealed the widespread occurrence of 19 various antifungals in natural waters and other matrices at alarmingly high concentrations. Due to the inefficiency of conventional water treatment in removing these compounds, advanced oxidation processes, membrane filtration, and adsorption techniques have been developed as promising decontamination methods.In conclusion, this review emphasizes the urgent need for a comprehensive understanding of the presence, fate, and removal of antifungal drugs in the environment. By addressing the current knowledge gaps and exploring future prospects, this study contributes to the development of strategies for mitigating the environmental impact of antifungal drugs and protecting ecosystems and human health.

Long-term exposure of Allonais inaequalis to a mixture of antibiotics in freshwater and synthetic wastewater matrices: Reproduction, recovery, and swimming responses

Antibiotics from sulfonamide, fluoroquinolone, and diaminopyrimidine classes are widely used in human and veterinary medicine, and their combined occurrence in the aquatic environment is increasing around the world. In parallel, the understanding of how mixtures of these compounds affect non-target species from tropical freshwaters is scarce. Thus, this work aimed to study the long-term reproductive, recovery, and swimming effects of mixtures of 12 antibiotics from three different classes (up to 10 μg L-1 ) added to freshwater (FWM) and synthetic wastewater (SWM) matrices on freshwater worm Allonais inaequalis. Results revealed that at the reproduction level, the exposure to antibiotics in the SWM matrix does not cause a significant toxic effect on species after 10 days. On the other hand, exposures to initial dose mixtures (10 μg L-1 each) in FWM caused a significant reduction of offspring by 19.2%. In addition, recovery bioassays (10 days in an antibiotic-free environment) suggested that A. inaequalis has reduced offspring production due to previous exposure to antibiotic mixtures in both matrices. Furthermore, despite slight variation in swimming speed over treatments, no significant differences were pointed out. Regarding antibiotics in the water matrices after 10-day exposures, the highest concentrations were up to 2.7, 7.8, and 4.2 μg L-1 for antibiotics from sulfonamide, fluoroquinolone, and diaminopyrimidine classes, respectively. These findings suggest that a species positioned between primary producers and secondary consumers may experience late reproductive damage even in an antibiotic-free zone, after previous 10-day exposure to antibiotic mixtures. PRACTITIONER POINTS: A mixture of sulfonamide, fluoroquinolone, and diaminopyrimidine antibiotics in freshwater affects the offspring production of A. inaequalis after 10 days. After the 10-day antibiotic exposure, the reproduction of A. inaequalis remains affected in an antibiotic-free environment over the recovery period. The swimming speed of the worms does not change after 10 days of exposure to the antibiotic mixture. The concentration of dissolved solids can limit the natural degradation of sulfonamide, fluoroquinolone, and diaminopyrimidine antibiotics in the aquatic environment.

Seasonal profile of common pharmaceuticals in edible bivalve molluscs

Pharmaceuticals are recognised as environmental contaminants of emerging concern (CECs) due to their increasing presence in the aquatic environment, along with high bioactivity linked to their therapeutic use. Therefore, information on environmental levels is urgently required. This study examined the presence of a range of common pharmaceuticals in oysters and mussels intended for human consumption from England and Wales using stable isotope dilution tandem mass spectrometry. A range of compounds were detected in bivalve tissue, with the Selective Serotonin Reuptake Inhibitor antidepressant sertraline being most abundant, reaching a maximum concentration of 22.1 ng/g wet weight shellfish tissue. Levels of all pharmaceuticals showed seasonal and geographical patterns. A dietary risk assessment revealed that the levels of pharmaceuticals identified in bivalve molluscs represent a clear hazard, but not a risk for the consumer. This study highlights the requirement for further monitoring of the presence of pharmaceuticals and other CECs in bivalve molluscs.

Pharmaceuticals and endocrine disrupting compounds modulate adverse effects of climate change on resource quality in freshwater food webs

Freshwater biodiversity, ecosystem functions and services are changing at an unprecedented rate due to the impacts of vast number of stressors overlapping in time and space. Our study aimed at characterizing individual and combined impacts of pollution with pharmaceuticals (PhACs) and endocrine disrupting compounds (EDCs) and increased water temperature (as a proxy for climate change) on primary producers and first level consumers in freshwaters. We conducted a microcosm experiment with a simplified freshwater food web containing moss (Bryophyta) and shredding caddisfly larvae of Micropterna nycterobia (Trichoptera). The experiment was conducted with four treatments; control (C), increased water temperature + 4 °C (T2), emerging contaminants' mix (EC = 15 PhACs & 5 EDCs), and multiple stressor treatment (MS = EC + T2). Moss exhibited an overall mild response to selected stressors and their combination. Higher water temperature negatively affected development of M. nycterobia through causing earlier emergence of adults and changes in their lipidome profiles. Pollution with PhACs and EDCs had higher impact on metabolism of all life stages of M. nycterobia than warming. Multiple stressor effect was recorded in M. nycterobia adults in metabolic response, lipidome profiles and as a decrease in total lipid content. Sex specific response to stressor effects was observed in adults, with impacts on metabolome generally more pronounced in females, and on lipidome in males. Thus, our study highlights the variability of both single and multiple stressor impacts on different traits, different life stages and sexes of a single insect species. Furthermore, our research suggests that the combined impacts of warming, linked to climate change, and contamination with PhACs and EDCs could have adverse consequences on the population dynamics of aquatic insects. Additionally, these findings point to a potential decrease in the quality of resources available for both aquatic and potentially terrestrial food webs.

Combined effects of climate warming and pharmaceuticals on a tri-trophic freshwater food web

Multiple anthropogenic stressors influence the functioning of lakes and ponds, but their combined effects are often little understood. We conducted two mesocosm experiments to evaluate the effects of warming (+4 °C above ambient temperature) and environmentally relevant concentrations of a mixture of commonly used pharmaceuticals (cardiovascular, psychoactive, antihistamines, antibiotics) on tri-trophic food webs representative of communities in ponds and other small standing waters. Communities were constituted of phyto- and zooplankton and macroinvertebrates (molluscs and insects) including benthic detritivores, grazers, omnivorous scrapers, omnivorous piercers, water column predators, benthic predators, and phytophilous predators. We quantified the main and interactive effects of warming and pharmaceuticals on each trophic level in the pelagic community and attributed them to the direct effects of both stressors and the indirect effects arising through biotic interactions. Warming and pharmaceuticals had stronger effects in the summer experiment, altering zooplankton community composition and causing delayed or accelerated emergence of top insect predators (odonates). In the summer experiment, both stressors and top predators reduced the biomass of filter-feeding zooplankton (cladocerans), while warming and pharmaceuticals had opposite effects on phytoplankton. In the winter experiment, the effects were much weaker and were limited to a positive effect of warming on phytoplankton biomass. Overall, we show that pharmaceuticals can exacerbate the effects of climate warming in freshwater ecosystems, especially during the warm season. Our results demonstrate the utility of community-level studies across seasons for risk assessment of multiple emerging stressors in freshwater ecosystems.

Environmental fate and risk evolution of calcium channel blockers from chlorine-based disinfection to sunlit surface waters

Organic micropollutants present in disinfected wastewater and discharged to sunlit surface waters may be transformed by multiple processes, such as chlorination due to the presence of chlorine residuals, solar irradiation as well as solar-irradiated chlorine residues. This study reports, for the first time, the multi-scenario degradation kinetics, transformation products, and risk evolution of calcium channel blockers (CCBs), a class of emerging pharmaceutical contaminants with worldwide prevalence in natural waters and wastewater. It was found that the chlorination of the studied CCBs (amlodipine (AML) and verapamil (VER)) was dominated by the reaction of HOCl with their neutral species, with second-order rate constants of 6.15×104 M-1 s-1 (AML) and 7.93×103 M-1 s-1 (VER) at pH 5.0-11.0. Bromination is much faster than chlorination, with the measured kapp,HOBr values of 2.94×105 M-1 s-1 and 6.58×103 M-1 s-1 for AML and VER, respectively, at pH 7.0. Furthermore, both CCBs would undergo photolytic attenuations with hydroxyl and carbonate radicals as the dominant reactive species in water. Notably, free chlorine mainly contributed to their abatement during the solar/chlorine treatment. Additionally, the halogen addition on the aromatic ring was observed during chlorination and bromination of the two CCBs. Cyclization was observed under solar irradiation only, while the aromatic ring was opened in the solar/chlorine system. Some products generated by the three transformation processes exhibited non-negligible risks of high biodegradation recalcitrance and toxicity, potentially threatening the aquatic environment and public health. Overall, this study elucidated the environmental fate of typical CCBs under different transformation processes to better understand the resulting ecological risks in these environmental scenarios.

Tracing COVID-19 drugs in the environment: Are we focusing on the right environmental compartment?

The Coronavirus Disease 2019 (COVID-19) pandemic led to over 770 million confirmed cases, straining public healthcare systems and necessitating extensive and prolonged use of synthetic chemical drugs around the globe for medical treatment and symptom relief. Concerns have arisen regarding the massive release of active pharmaceutical ingredients (APIs) and their metabolites into the environment, particularly through domestic sewage. While discussions surrounding this issue have primarily centered on their discharge into aquatic environments, particularly through treated effluent from municipal wastewater treatment plants (WWTPs), one often overlooked aspect is the terrestrial environment as a significant receptor of pharmaceutical-laden waste. This occurs through the disposal of sewage sludge, for instance, by applying biosolids to land or non-compliant disposal of sewage sludge, in addition to the routine disposal of expired and unused medications in municipal solid wastes. In this article, we surveyed sixteen approved pharmaceuticals for treating COVID-19 and bacterial co-infections, along with their primary metabolites. For this, we delved into their physiochemical properties, ecological toxicities, environmental persistence, and fate within municipal WWTPs. Emphasis was given on lipophilic substances with log Kow >3.0, which are more likely to be found in sewage sludge at significant factions (25.2%-75.0%) of their inputs in raw sewage and subsequently enter the terrestrial environment through land application of biosolids, e.g., 43% in the United States and as high as 96% in Ireland or non-compliant practices of sewage sludge disposal in developing communities, such as open dumping and land application without prior anaerobic digestion. The available evidence underscores the importance of adequately treating and disposing of sewage sludge before its final disposal or land application in an epidemic or pandemic scenario, as mismanaged sewage sludge could be a significant vector for releasing pharmaceutical compounds and their metabolites into the terrestrial environment.

Ecotoxicological effects of antibiotic adsorption behavior of microplastics and its management measures

Microplastics adsorb heavy metals and organic pollutants to produce combined pollution. Recently, the adsorption behavior of antibiotics on microplastics has received increasing attention. Exploring the sorption behavior of pollutants on microplastics is an important reference in understanding their ecological and environmental risk studies. In this paper, by reviewing the academic literature in recent years, we clarified the current status of research on the adsorption behavior of antibiotics on microplastics, discussed its potential hazards to ecological environment and human health, and summarized the influence of factors on the adsorption mechanisms. The results show that the adsorption behavior of antibiotics on microplastics is controlled by the physical and chemical properties of antibiotics, microplastics, and water environment. Antibiotics are adsorbed on microplastics through physical and chemical interactions, which include hydrophobic interaction, partitioning, electrostatic interaction, and other non-covalent interactions. Intensity of adsorption between them is mainly determined by their physicochemical properties. The basic physicochemical properties of the aqueous environment (e.g., pH, salinity, ionic strength, soluble organic matter content, and temperature) will affect the physicochemical properties of microplastics and antibiotics (e.g., particle size, state of dispersibility, and morphology), leading to differences in the type and strength of their interactions. This paper work is expected to provide a meaningful perspective for better understanding the potential impacts of antibiotic adsorption behavior of microplastics on aquatic ecology and human health. In the meantime, some indications for future related research are provided.

When and How to Conduct Ecotoxicological Tests Using Natural Field-Collected Sediment

In recent years, the sediment compartment has gained more attention when performing toxicity tests, with a growing emphasis on gaining more ecological relevance in testing. Though many standard guidelines recommend using artificially formulated sediment, most sediment studies are using natural sediment collected in the field. Although the use of natural field-collected sediment contributes to more environmentally realistic exposure scenarios and higher well-being for sediment-dwelling organisms, it lowers comparability and reproducibility among studies as a result of, for example, differences in the base sediment depending on sampling site, background contamination, particle size distribution, or organic matter content. The aim of this methodology contribution is to present and discuss best practices related to collecting, handling, describing, and applying natural field-collected sediment in ecotoxicological testing. We propose six recommendations: (1) natural sediment should be collected at a well-studied site, historically and by laboratory analysis; (2) larger quantities of sediment should be collected and stored prior to initiation of an experiment to ensure a uniform sediment base; (3) any sediment used in ecotoxicological testing should be characterized, at the very least, for its water content, organic matter content, pH, and particle size distribution; (4) select spiking method, equilibration time, and experimental setup based on the properties of the contaminant and the research question; (5) include control-, treated similarly to the spiked sediment, and solvent control sediment when appropriate; and (6) quantify experimental exposure concentrations in the overlying water, porewater (if applicable), and bulk sediment at least at the beginning and the end of each experiment. Environ Toxicol Chem 2023;00:1-10. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Insights in Pharmaceutical Pollution: The Prospective Role of eDNA Metabarcoding

Environmental pollution is a growing threat to natural ecosystems and one of the world's most pressing concerns. The increasing worldwide use of pharmaceuticals has elevated their status as significant emerging contaminants. Pharmaceuticals enter aquatic environments through multiple pathways related to anthropogenic activity. Their high consumption, insufficient waste treatment, and the incapacity of organisms to completely metabolize them contribute to their accumulation in aquatic environments, posing a threat to all life forms. Various analytical methods have been used to quantify pharmaceuticals. Biotechnology advancements based on next-generation sequencing (NGS) techniques, like eDNA metabarcoding, have enabled the development of new methods for assessing and monitoring the ecotoxicological effects of pharmaceuticals. eDNA metabarcoding is a valuable biomonitoring tool for pharmaceutical pollution because it (a) provides an efficient method to assess and predict pollution status, (b) identifies pollution sources, (c) tracks changes in pharmaceutical pollution levels over time, (d) assesses the ecological impact of pharmaceutical pollution, (e) helps prioritize cleanup and mitigation efforts, and (f) offers insights into the diversity and composition of microbial and other bioindicator communities. This review highlights the issue of aquatic pharmaceutical pollution while emphasizing the importance of using modern NGS-based biomonitoring actions to assess its environmental effects more consistently and effectively.

Growth inhibition, oxidative stress and characterisation of mortality in green algae under the influence of beta-blockers and non-steroidal anti-inflammatory drugs

Bisoprolol and ketoprofen are widely used pharmaceuticals in medical treatment hence these substances are occurring in wastewaters and in water environment. This research investigated the toxic effects of bisoprolol and ketoprofen on two microalgae taxa, Chlorella vulgaris and Desmodesmus armatus. The results showed that both drugs inhibited the growth of the species tested and induced a decrease in chlorophyll a content compared to controls. Ketoprofen turned out to be harmful to algae as the half maximal effective concentration (EC50) values (14 days) were 37.69 mg L-1 for C. vulgaris and 40.93 mg L-1 for D. armatus. On the other hand, for bisoprolol, the EC50 values were greater than the established NOEC, 100 mg L-1. Bisoprolol and ketoprofen induced oxidative stress in the tested microorganisms, as indicated by changes in the activities of antioxidant enzymes. Exposure to 100 mg L-1 of drugs significantly increased the activity of catalase, peroxidase and superoxide dismutase. Fluorescence microscopy showed that both medicaments changed the cells' morphology. There was atrophy of chlorophyll in the cells, moreover, dying multinuclear cells and cells without nuclei were observed. In addition, there were atrophic cells, namely cells that lacked nuclei and chlorophyll. Profile area analyses showed that bisoprolol and ketoprofen treated C. vulgaris cells were approximately 4 and 2 times greater compared to control ones. Our experimental findings highlight the ecotoxicological threats for aquatic primary producers from bisoprolol and ketoprofen and provide insight into the characteristics of their death.

Coupled multimedia fate and bioaccumulation models for predicting fate of florfenicol and fluoroquinolones in water and fish organs in the seasonal ice-sealed reservoir

Ice formation in reservoirs could promote the accumulation of antibiotics in fish, potentially leading to elevated concentrations in fish muscles, kidneys, and livers. However, for the seasonal ice-sealed reservoirs, antibiotic sampling and detecting conditions in water and fish are normally limited by the ice cover. Additionally, previous studies on the prediction of antibiotics accumulated in seasonal ice-sealed reservoir fish are scarce. This study presents a coupled model incorporating a multimedia fate model and a bioaccumulation model to predict antibiotic fate in water and the muscles, kidneys, and livers of fish in seasonal ice-sealed reservoirs. Prediction concentrations of florfenicol were higher than those of ofloxacin and norfloxacin in both water and fish from the seasonal ice-sealed reservoir. Log bioaccumulation factors of antibiotics in Cyprinus carpio and Hypophthalmichthys nobilis in January 2021 were higher than those in October 2020 by 21.5% and 12.6%, respectively. Antibiotics mean transfer fluxes from water to fish muscles, kidneys, and livers increased owing to the reservoir ice-cover formation date advancing by 13.0%, 77.1%, and 61.0%, respectively. This work provides a modeling tool for investigating the fate and mass transfer flux of antibiotics in biological and environmental phases in seasonal ice-sealed reservoirs.

Environmentally relevant concentrations of antidepressant mirtazapine impair the neurodevelopment of zebrafish (Danio rerio)

Mirtazapine is a commonly prescribed antidepressant and has been found widespread in aquatic environments. However, its toxicities to aquatic organisms has rarely been explored. Herein, we conducted a comprehensive study on the developmental effects of mirtazapine on early life stages of zebrafish at environmentally relevant concentrations (3.9 ng/L and 43.5 ng/L). Out of the endpoints measured, spontaneous contraction of embryos at 24 h post fertilization (hpf) and hatching rate and heart rate of embryos at 50 hpf and 56 hpf, respectively, were significantly affected. In light-dark transition behavior test, mirtazapine significantly reduced the swimming frequency and swimming speed of embryos at both concentrations of 3.9 ng/L and 43.5 ng/L. Furthermore, the total swimming distances in dark conditions were also significantly reduced. Transcriptomic analysis was further conducted. It demonstrated that the decreased neural activities in embryos may be associated with altered epinephrine and neuregulin signaling. The present results fill a data gap regarding the exposure of fish to mirtazapine at environmentally relevant concentrations and provide new insights into the neurotoxic mechanisms of mirtazapine exposure.

[Disposal of drugs and the ensuing environmental impacts: an integrative review of the literature]

The scope of this article is to investigate the national and international evidence available on the forms of drug disposal and the presence of drugs in environmental matrices. It involved an integrative review of the literature conducted in the PubMed, SciELO and Virtual Health Library (VHL) databases, which included articles in English, Spanish and Portuguese published between 2010 and 2020. Twenty-six articles were selected, which revealed the incorrect disposal of medicines by professionals and consumers due mainly to the lack of knowledge about the environmental impacts that they may cause. Studies have highlighted the contamination of water, sewage and sediments by incorrectly discarded drugs. Furthermore, it was observed that aquatic living creatures can be impacted by the presence of drugs in environmental matrices. The incorrect disposal of drugs continues to be a reality in the evidence assessed, which leads to the contamination of environmental matrices and is often not removed by wastewater treatment plants and interferes with the equilibrium of environmental life.

Bioaccumulation/bioconcentration of pharmaceutical active compounds in aquatic organisms: Assessment and factors database

There is increasing evidence that the presence of certain pharmaceuticals in the environment leads to biota exposure and constitute a potential risk for ecosystems. Bioaccumulation is an essential focus of risk assessment to evaluate at what degree emerging contaminants are a hazard both to the environment and the individuals that inhabit it. The main goals of the present review are 1) to summarize and describe the research and factors that should be taken into account in the evaluation of bioaccumulation of pharmaceuticals in aquatic organisms; and 2) to provide a database and a critical review of the bioaccumulation/bioconcentration factors (BAF or BCF) of these compounds in organisms of different trophic levels. Most studies fall into one of two categories: laboratory-scale absorption and purification tests or field studies and, to a lesser extent, large-scale, semi-natural system tests. Although in the last 5 years there has been considerable progress in this field, especially in species of fish and molluscs, research is still limited on other aquatic species like crustaceans or algae. This revision includes >230 bioconcentration factors (BCF) and >530 bioaccumulation factors (BAF), determined for 113 pharmaceuticals. The most commonly studied is the antidepressant group, followed by diclofenac and carbamazepine. There is currently no reported accumulation data on certain compounds, such as anti-cancer drugs. BCFs are highly influenced by experimental factors (notably the exposure level, time or temperature). Field BAFs are superior to laboratory BCFs, highlighting the importance of field studies for reliable assessments and in true environmental conditions. BAF data appears to be organ, species and compound-specific. The potential impact on food web transfer is also considered. Among different aquatic species, lower trophic levels and benthic organisms exhibit relatively higher uptake of these compounds.

Bioaccumulation Kinetics of Model Pharmaceuticals in the Freshwater Unionid Pondmussel, Sagittunio subrostratus

Bioaccumulation of ionizable pharmaceuticals has been increasingly studied, with most reported aquatic tissue concentrations in field or laboratory experiments being from fish. However, higher levels of antidepressants have been observed in bivalves compared with fish from effluent-dominated and dependent surface waters. Such observations may be important for biodiversity because approximately 70% of freshwater bivalves in North America are considered to be vulnerable to extinction. Because experimental bioaccumulation information for freshwater bivalves is lacking, we examined accumulation dynamics in the freshwater pondmussel, Sagittunio subrostratus, following exposure to a model weak acid, acetaminophen (mean (±SD) = 4.9 ± 1 µg L^-1 ), and a model weak base, sertraline (mean (±SD) = 1.1 ± 1.1 µg L^-1 ) during 14-day uptake and 7-day depuration experiments. Pharmaceutical concentrations were analyzed in water and tissue using isotope dilution liquid chromatography-tandem mass spectrometry. Mussels accumulated two orders of magnitude higher concentrations of sertraline (31.7 ± 9.4 µg g^-1 ) compared to acetaminophen (0.3 ± 0.1 µg g^-1 ). Ratio and kinetic-based bioaccumulation factors of 28,836.4 (L kg^-1 ) and 34.9 (L kg^-1 ) were calculated for sertraline and for acetaminophen at 65.3 (L kg^-1 ) and 0.13 (L kg^-1 ), respectively. However, after 14 days sertraline did not reach steady-state concentrations, although it was readily eliminated by S. subrostratus. Acetaminophen rapidly reached steady-state conditions but was not depurated over a 7-day period. Future bioaccumulation studies of ionizable pharmaceuticals in freshwater bivalves appear warranted. Environ Toxicol Chem 2023;00:1-7. © 2023 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.

Evaluating chemicals of emerging concern in the Ganga River at the two major cities Prayagraj and Varanasi through validated analytical approaches

Evaluating environmental water quality means to assess and protect the environment against unfriendly impacts from various organic impurities emerging from industrial emissions and those released during harvesting. Potential risks related with release of polycyclic aromatic hydrocarbons (PAHs), pesticides and pharmaceuticals (PhAcs), and personal care products (PCPs) into the environment have turned into an increasingly serious issue in ecological safety. Monitoring helps in control of chemicals and ecological status compliance to safeguard specific water uses, for example, drinking water abstraction. A longitudinal review was carried out for 55 different persistent organic pollutants (POPs) for the Ganga River which passes through the urban areas of Prayagraj and Varanasi, India, through validated analytical approaches and measurement uncertainty (MU) estimation to assess their potential use for routine analysis. Furthermore, environmental risk assessment (ERA) carried out in the present study has revealed risk quotient (RQ) higher than 1 in a portion of the aquatic bodies. Using a conservative RQ strategy, POPs were assessed for having extensive risks under acute and chronic exposure, proposing that there is currently critical ecological risk identified with these compounds present in the Ganga River. In general, these outcomes demonstrate a significant contribution for focusing on measures and feasible techniques to minimize the unfavorable effects of contaminants on the aquatic environment.

An Overview of the Impact of Pharmaceuticals on Aquatic Microbial Communities

Pharmaceuticals are present as pollutants in several ecosystems worldwide. Despite the reduced concentrations at which they are detected, their negative impact on natural biota constitutes a global concern. The consequences of pharmaceuticals' presence in water sources and food have been evaluated with a higher detail for human health. However, although most of the pharmaceuticals detected in the environment had not been designed to act against microorganisms, it is of utmost importance to understand their impact on the environmental native microbiota. Microbial communities can suffer serious consequences from the presence of pharmaceuticals as pollutants in the environment, which may directly impact public health and ecosystem equilibrium. Among this class of pollutants, the ones that have been studied in more detail are antibiotics. This work aims to provide an overview of the impacts of different pharmaceuticals on environmental biofilms, more specifically in biofilms from aquatic ecosystems and engineered water systems. The alterations caused in the biofilm function and characteristics, as well as bacteria antimicrobial tolerance and consequently the associated risks for public health, are also reviewed. Despite the information already available on this topic, the need for additional data urges the assessment of emerging pollutants on microbial communities and the potential public health impacts.

Non-steroidal anti-inflammatory drugs caused an outbreak of inflammation and oxidative stress with changes in the gut microbiota in rainbow trout (Oncorhynchus mykiss)

One of the main contributors to pharmaceutical pollution of surface waters are non-steroidal anti-inflammatory drugs (NSAIDs) that contaminate the food chain and affect non-target water species. As there are not many studies focusing on toxic effects of NSAIDs on freshwater fish species and specially effects after dietary exposure, we selected rainbow trout (Oncorhynchus mykiss) as the ideal model to examine the impact of two NSAIDs - diclofenac (DCF) and ibuprofen (IBP). The aim of our study was to test toxicity of environmentally relevant concentrations of these drugs together with exposure doses of 100× higher, including their mixture; and to deepen knowledge about the mechanism of toxicity of these drugs. This study revealed kidneys as the most affected organ with hyalinosis, an increase in oxidative stress markers, and changes in gene expression of heat shock protein 70 to be signs of renal toxicity. Furthermore, hepatotoxicity was confirmed by histopathological analysis (i.e. dystrophy, congestion, and inflammatory cell increase), change in biochemical markers, increase in heat shock protein 70 mRNA, and by oxidative stress analysis. The gills were locally deformed and showed signs of inflammatory processes and necrotic areas. Given the increase in oxidative stress markers and heat shock protein 70 mRNA, severe impairment of oxygen transport may be one of the toxic pathways of NSAIDs. Regarding the microbiota, an overgrowth of Gram-positive species was detected; in particular, significant dysbiosis in the Fusobacteria/Firmicutes ratio was observed. In conclusion, the changes observed after dietary exposure to NSAIDs can influence the organism homeostasis, induce ROS production, potentiate inflammations, and cause gut dysbiosis. Even the environmentally relevant concentration of NSAIDs pose a risk to the aquatic ecosystem as it changed O. mykiss health parameters and we assume that the toxicity of NSAIDs manifests itself at the level of mitochondria and proteins.

Invertebrates differentially bioaccumulate pharmaceuticals: Implications for routine biomonitoring

Surface water quality monitoring programs have been developed to examine traditional contaminants, such as persistent organic pollutants (POPs). However, urbanization, which is increasing around the world, is increasing discharge of treated wastewater and raw sewage in many regions. Pharmaceuticals and their metabolites represent typical markers of such trajectories in urbanization. We selected an ongoing monitoring program, which was designed for routine surveillance of nonionizable POPs in different aquatic matrices, to examine the occurrence of 67 pharmaceuticals and their metabolites in water and multiple bioindicator matrices: benthic invertebrates, juvenile fish, and adult fish (plasma and muscle tissue) from ten river systems with varying levels of watershed development. In addition, we placed zebra mussels and passive samplers in situ for a fixed period. A statistically significant relationship between pharmaceutical levels in passive samplers and biota was found for caged zebra mussels and benthic invertebrates, while only a few pharmaceuticals were identified in fish matrices. Invertebrates, which have received relatively limited study for pharmaceutical bioaccumulation, accumulated more pharmaceuticals than fish, up to thirty different substances. The highest concentration was observed for sertraline in zebra mussels and telmisartan in benthic invertebrates (83 and 31 ng/g ww, respectively). Our results across diverse study systems indicate that ongoing surface water quality monitoring programs, which were originally designed for traditional organic pollutants, need to be revised to account for bioaccumulation dynamics of pharmaceuticals and other ionizable contaminants. Aquatic monitoring programs routinely examine accumulation of nonionizable organic pollutants; however, we identified that these efforts need to be revised to account for bioaccumulation of ionizable contaminants, which reached higher levels in invertebrates than in fish.

Bioaccumulation and bioamplification of pharmaceuticals and endocrine disruptors in aquatic insects

Environmental fate of emerging contaminants such as pharmaceuticals and endocrine disrupting compounds at the aquatic terrestrial boundary are largely unexplored. Aquatic insects connect aquatic and terrestrial food webs as their life cycle includes aquatic and terrestrial life stages, thus they represent an important inter-habitat linkage not only for energy and nutrient flow, but also for contaminant transfer to terrestrial environments. We measured the concentrations of pharmaceuticals and endocrine disrupting compounds in the larval and adult tissues (last larval stages and teneral adults) of five Odonata species sampled in a wastewater-impacted river, in order to examine their bioaccumulation and bioamplification at different taxonomic levels. Twenty different compounds were bioaccumulated in insect tissues, with majority having higher concentrations (up to 90% higher) in aquatic larvae compared to terrestrial adults (reaching 88 ng/g for 1H-benzotriazole). However, increased concentration in adults was observed for seven compounds in at least one suborder (41% of the accumulated), confirming contaminants bioamplification across the metamorphosis. Both, bioaccumulation and bioamplification differed at various taxa levels; the order (Odonata), suborder (Anisoptera and Zygoptera) and species level. Highest variability was observed between Anisoptera and Zygoptera, due to the underlying differences in their ecology. Generally, Zygoptera had higher concentrations of contaminants in both larvae and adults. Additionally, we aimed at predicting effects of contaminant properties on bioaccumulation and bioamplification patterns using the commonly used physicochemical and pharmacokinetic descriptors on both order and suborder levels, however, neither of the two processes could be consistently predicted with simple linear models. Our study highlights the importance of taxonomy in studies aiming at advancing the understanding of contaminant exchange between aquatic and terrestrial food webs, as higher taxonomic categories include ecologically diverse groups, whose contribution to "the dark side of subsidies" could substantially differ.

Effects of Trace Metals and Municipal Wastewater on the Ephemeroptera, Plecoptera, and Trichoptera of a Stream Community

Abundances of EPT larvae sampled in a Central European locality affected by mining and smelting, as well as by the continual inflow of treated communal wastewaters (WWs), were recorded. High concentrations of trace metals in water (maximum 1200 µg·L–1 for zinc) and sediments (maximum 140,000 mg·kg–1 in dry weight for lead) were found at the most contaminated sites. The highest loads of pesticides, pharmaceuticals, and illegal drugs were found under the WW effluent. Other associated factors such as the physicochemical parameters of the water and alterations to microhabitats were also evaluated and taken into account. Although EPT richness was lower at affected sites, abundances did not fall. Stoneflies were dominant at unaffected sites, while caddisflies dominated at affected sites. Only baetid mayflies were detected at the sites contaminated by trace metals and WWs; ephemerellid, heptageniid, and leptophlebiid mayflies were absent from these sites. The site contaminated by trace metals was also inhabited by numerous limnephilid caddisflies, in which limb malformations were detected in up to 11.8% of all specimens of a single taxon. Downstream from the entrance of the WWs, the locality was dominated by hydropsychid caddisflies. The increasing prevalence of predator or passive filter-feeding strategies in these EPT communities was significantly related to increasing water conductivity and acute ecosystemic exposure to ‘poorly treated’ WWs.

Application of a novel prioritisation strategy using non-target screening for evaluation of temporal trends (1969-2017) of contaminants of emerging concern (CECs) in archived lynx muscle tissue samples

Most environmental monitoring studies of contaminants of emerging concern (CECs) focus on aquatic species and target specific classes of CECs. Even with wide-scope target screening methods, relevant CECs may be missed. In this study, non-target screening (NTS) was used for tentative identification of potential CECs in muscle tissue of the terrestrial top predator Eurasian lynx (Lynx lynx). Temporal trend analysis was applied as a prioritisation tool for archived samples, using univariate statistical tests (Mann-Kendall and Spearman rank). Pooled lynx muscle tissue collected from 1969 to 2017 was analysed with an eight-point time series using a previously validated screening workflow. Following peak detection, peak alignment, and blank subtraction, 12,941 features were considered for statistical analysis. Prioritisation by time-trend analysis detected 104 and 61 features with statistically significant increasing and decreasing trends, respectively. Following probable molecular formula assignment and elucidation with MetFrag, two compounds with increasing trends, and one with a decreasing trend, were tentatively identified. These results show that, despite low expected concentration levels and high matrix effects in terrestrial species, it is possible to prioritise CECs in archived lynx samples using NTS and univariate statistical approaches.

Presence of pharmaceuticals and their metabolites in wild-living aquatic organisms - Current state of knowledge

In the last decades an increasing number of studies has been published concerning contamination of aquatic ecosystems with pharmaceuticals. Yet, the distribution of these chemical compounds in aquatic environments raises many questions and uncertainties. Data on the presence of selected pharmaceuticals in the same water bodies varies significantly between different studies. Therefore, since early 1990 s, wild organisms have been used in research on environmental contamination with pharmaceuticals. Indeed, pharmaceutical levels measured in biological matrices may better reflect their overall presence in the aquatic environments as such levels include not only direct exposure of a given organisms to a specific pollutant but also processes such as bioaccumulation and biomagnification. In the present paper, data concerning occurrence of pharmaceuticals in aquatic biota was reviewed. So far, pharmaceuticals have been studied mainly in fish and molluscs, with only a few papers available on crustaceans and macroalgae. The most commonly found pharmaceuticals both in freshwater and marine organisms are antibiotics, antidepressants and NSAIDS while there is no information about the presence of anticancer drugs in aquatic organisms. Furthermore, only single studies were conducted in Africa and Australia. Hence, systematization of up-to-date knowledge, the main aim of this review, is needed for further research targeting.

Novel prioritisation strategies for evaluation of temporal trends in archived white-tailed sea eagle muscle tissue in non-target screening

Environmental monitoring studies based on target analysis capture only a small fraction of contaminants of emerging concern (CECs) and miss pollutants potentially harmful to wildlife. Environmental specimen banks, with their archived samples, provide opportunities to identify new CECs by temporal trend analysis and non-target screening. In this study, archived white-tailed sea eagle (Haliaeetus albicilla) muscle tissue was analysed by non-targeted high-resolution mass spectrometry. Univariate statistical tests (Mann-Kendall and Spearman rank) for temporal trend analysis were applied as prioritisation methods. A workflow for non-target data was developed and validated using an artificial time series spiked at five levels with gradient concentrations of selected CECs (n = 243). Pooled eagle muscle tissues collected 1965-2017 were then investigated with an eight-point time series using the validated screening workflow. Following peak detection, peak alignment, and blank subtraction, 14 409 features were considered for statistical analysis. Prioritisation by time-trend analysis detected 207 features with increasing trends. Following unequivocal molecular formula assignment to prioritised features and further elucidation with MetFrag and EU Massbank, 13 compounds were tentatively identified, of which four were of anthropogenic origin. These results show that it is possible to prioritise new CECs in archived biological samples using univariate statistical approaches.

Water reuse for aquaculture: Comparative removal efficacy and aquatic hazard reduction of pharmaceuticals by a pond treatment system during a one year study

Aquaculture is increasing at the global scale, and beneficial reuse of wastewater is becoming crucial in some regions. Here we selected a unique tertiary treatment system for study over a one-year period. This experimental ecosystem-based approach to effluent management included a treated wastewater pond (TWP), which receives 100% effluent from a wastewater treatment plant, and an aquaculture pond (AP) that receives treated water from the TWP for fish production. We examined the fate of a wide range of pharmaceutically active compounds (PhACs) in this TWP-AP system and a control pond fed by river water using traditional grab sampling and passive samplers. We then employed probabilistic approaches to examine exposure hazards. Telmisartan, carbamazepine, diclofenac and venlafaxine, exceeded ecotoxicological predicted no effect concentrations in influent wastewater to the TWP, but these water quality hazards were consistently reduced following treatment in the TWP-AP system. In addition, both grab and passive sampling approaches resulted in similar occurrence patterns of studied compounds, which highlights the potential of POCIS use for water monitoring. Based on the approach taken here, the TWP-AP system appears useful as a tertiary treatment step to reduce PhACs and decrease ecotoxicological and antibiotic resistance water quality hazards prior to beneficial reuse in aquaculture.

Water temperature affects the biotransformation and accumulation of a psychoactive pharmaceutical and its metabolite in aquatic organisms

Pharmaceutically active compounds (PhACs) have been shown to accumulate in aquatic and riparian food-webs. Yet, our understanding of how temperature, a key environmental factor in nature, affects uptake, biotransformation, and the subsequent accumulation of PhACs in aquatic organisms is limited. In this study, we tested to what extent bioconcentration of an anxiolytic drugs (temazepam and oxazepam) is affected by two temperature regimes (10 and 20 °C) and how the temperature affects the temazepam biotransformation and subsequent accumulation of its metabolite (oxazepam) in aquatic organisms. We used European perch (Perca fluviatilis) and dragonfly larvae (Sympetrum sp.), which represent predator and prey species of high ecological relevance in food chains of boreal and temperate aquatic ecosystems. Experimental organisms were exposed to target pharmaceuticals at a range of concentrations (0.2-6 µg L^-1) to study concentration dependent differences in bioconcentration and biotransformation. We found that the bioconcentration of temazepam in perch was significantly reduced at higher temperatures. Also, temperature had a strong effect on temazepam biotransformation in the fish, with the production and subsequent accumulation of its metabolite (oxazepam) being two-fold higher at 20 °C compared to 10 °C. In contrast, we found no temperature dependency for temazepam bioconcentration in dragonfly larvae and no detectable biotransformation of the parent compound that would result in measurable concentrations of oxazepam in this organism. Our results highlight that while organisms may share the same aquatic ecosystem, their exposure to PhACs may change differently across temperature gradients in the environment.

Suspect screening of pharmaceuticals in fish livers based on QuEChERS extraction coupled with high resolution mass spectrometry

The presence of pharmaceuticals and personal care products (PPCPs) in aquatic environments is of increasing concern due to the presence of residues in fish and aquatic organisms, and emerging antibiotic resistance. Wastewater release is an important contributor to the presence of these compounds in aquatic ecosystems, where they may accumulate in food webs. The traditional environmental surveillance approach relies on the targeted analysis of specific compounds, but more suspect screening methods have been developed recently to allow for the identification of a variety of contaminants. In this study, a method based on QuEChERS extraction - using acetonitrile/water mixture as solvent and PSA/C₁₈ for sample clean-up - was applied to identify pharmaceuticals and their metabolites in fish livers. Both target and suspect screening workflows were used and fish were sampled upstream and downstream of wastewater treatment plants from the Scioto River, Ohio (USA). The method performed well in terms of extraction of some target PPCPs, with recoveries generally above 90%, good repeatability (<20%), and linearity. Based on target analysis, lincomycin and sulfamethoxazole were two antibiotics identified in fish livers at average concentrations of 30.3 and 25.6 ng g^-1 fresh weight, respectively. Using suspect screening, another antibiotic, azithromycin and an antidepressant metabolite, erythrohydrobupropion were identified (average concentrations: 27.8 and 13.8 ng g^-1, respectively). The latter, reported, to the best of our knowledge, for the first time in fish livers, was also found at higher concentrations in fish livers sampled downstream vs. upstream. The higher frequency of detection for azithromycin in benthic feeding fish species (63%) as well as clusters identified between different foraging groups suggest that foraging behavior may be an important mechanism in the bioaccumulation of PPCPs. This study shows how suspect screening is effective in identifying new contaminants in fish livers, notably using differential analysis among different spatially distributed samples.

A critical review on environmental presence of pharmaceutical drugs tested for the covid-19 treatment

On March 11, 2020, the World Health Organization (WHO) declared COVID-19 a pandemic. The outbreak caused a worldwide impact, becoming a health threat to the general population and its professionals. To date, there are no specific antiviral treatments or vaccines for the COVID-19 infection, however, some drugs are being clinically tested. The use of these drugs on large scale raises great concern about their imminent environmental risk, since the elimination of these compounds by feces and urine associated with the inefficiency of sewage treatment plants in their removal can result in their persistence in the environment, putting in risk the health of humans and of other species. Thus, the goal of this work was to conduct a review of other studies that evaluated the presence of the drugs chloroquine, hydroxychloroquine, azithromycin, ivermectin, dexamethasone, remdesivir, favipiravir and some HIV antivirals in the environment. The research indicated the presence of these drugs in the environment in different regions, with concentration data that could serve as a basis for further comparative studies following the pandemic.

Exposure via biotransformation: Oxazepam reaches predicted pharmacological effect levels in European perch after exposure to temazepam

It is generally expected that biotransformation and excretion of pharmaceuticals occurs similarly in fish and mammals, despite significant physiological differences. Here, we exposed European perch (Perca fluviatilis) to the benzodiazepine drug temazepam at a nominal concentration of 2 µg L^-1 for 10 days. We collected samples of blood plasma, muscle, and brain in a time-dependent manner to assess its bioconcentration, biotransformation, and elimination over another 10 days of depuration in clean water. We observed rapid pharmacokinetics of temazepam during both the exposure and depuration periods. The steady state was reached within 24 h of exposure in most individuals, as was complete elimination of temazepam from tissues during depuration. Further, the biologically active metabolite oxazepam was produced via fish biotransformation, and accumulated significantly throughout the exposure period. In contrast to human patients, where a negligible amount of oxazepam is created by temazepam biotransformation, we observed a continuous increase of oxazepam concentrations in all fish tissues throughout exposure. Indeed, oxazepam accumulated more than its parent compound, did not reach a steady state during the exposure period, and was not completely eliminated even after 10 days of depuration, highlighting the importance of considering environmental hazards posed by pharmaceutical metabolites.

Pharmaceuticals Market, Consumption Trends and Disease Incidence Are Not Driving the Pharmaceutical Research on Water and Wastewater

Pharmaceuticals enhance our quality of life; consequently, their consumption is growing as a result of the need to treat ageing-related and chronic diseases and changes in the clinical practice. The market revenues also show an historic growth worldwide motivated by the increase on the drug demand. However, this positivism on the market is fogged because the discharge of pharmaceuticals and their metabolites into the environment, including water, also increases due to their inappropriate management, treatment and disposal; now, worldwide, this fact is recognized as an environmental concern and human health risk. Intriguingly, researchers have studied the most effective methods for pharmaceutical removal in wastewater; however, the types of pharmaceuticals investigated in most of these studies do not reflect the most produced and consumed pharmaceuticals on the market. Hence, an attempt was done to analyze the pharmaceutical market, drugs consumption trends and the pharmaceutical research interests worldwide. Notwithstanding, the intensive research work done in different pharmaceutical research fronts such as disposal and fate, environmental impacts and concerns, human health risks, removal, degradation and development of treatment technologies, found that such research is not totally aligned with the market trends and consumption patterns. There are other drivers and interests that promote the pharmaceutical research. Thus, this review is an important contribution to those that are interested not only on the pharmaceutical market and drugs consumption, but also on the links, the drivers and interests that motivate and determine the research work on certain groups of pharmaceuticals on water and wastewater.

A combination of six psychoactive pharmaceuticals at environmental concentrations alter the locomotory behavior of clonal marbled crayfish

Pharmaceutically active compounds (PhACs) are ubiquitous in the aquatic environment worldwide and considered emerging contaminants. Their effects on growth, behavior, and physiological processes of aquatic organisms have been identified even at very low concentrations. Ecotoxicological investigations have primarily focused on single compound exposure, generally at a range of concentrations. In the natural environment, pollutants seldom occur in isolation, but little is known about the effects and risks of combinations of chemicals. This study aimed to investigate the effects of concurrent exposure to six psychoactive PhACs on locomotory behavior and life history traits of clonal marbled crayfish Procambarus virginalis. Crayfish were exposed to ~1 μg L^-1 of the antidepressants sertraline, citalopram, and venlafaxine; the anxiolytic oxazepam; the opioid tramadol; and the widely abused psychostimulant methamphetamine. In the absence of shelter, exposed crayfish moved significantly shorter distances and at lower velocity and showed significantly less activity than controls. With available shelter, exposed crayfish moved significantly more distance, showed higher activity, and spent a significantly more time outside the shelter than controls. Molting, mortality, and spawning frequency did not vary significantly between the groups. Hemolymph glucose level did not vary among groups and was not correlated with observed behaviors. Results suggest that environmental concentrations of the tested compounds in combination can alter the behavior of non-target aquatic organisms as individual exposure of these compounds, which may lead to disruption of ecosystem processes due to their reduced caution in polluted conditions. Further research is needed using varied chemical mixtures, exposure systems, and habitats, considering molecular and physiological processes connected to behavior alterations.

Tissue-specific expression and activity of cytochrome P450 1A and 3A in rainbow trout (Oncorhynchus mykiss)

Piscine cytochrome P450 (CYP) enzymes play an important role in the metabolism of xenobiotics. Xenobiotics often act as inducers of CYP1A1 and CYP3A expression and activity in fish. We compared constitutive mRNA expression of CYP1A1, CYP3A27, and CYP3A45 and catalytic activity of CYP1A (7-ethoxyresorufin-O-deethylation, EROD) and CYP3A-like (benzyloxy-4-trifluoromethylcoumarin-O-debenzyloxylation, BFCOD) enzymes in the following six rainbow trout tissues: liver, gill, heart, brain, intestine, and gonad. mRNA expression and activity were present in all investigated tissues. The CYP1A1 mRNA expression was higher in the liver, gill, heart, and brain compared to gonad and intestine. The intestine was the main site of CYP3A27 and CYP3A45 expression. The highest EROD and BFCOD activity was observed in liver tissue followed in descending order by heart, brain, gill, intestine, and gonad. Such differences might be related to the role of CYP physiological functions in the specific tissue. Rainbow trout exposure to 50 mg/kg of β-naphthoflavone for 48 h resulted in a 7.5- and 5.9-fold increase in liver EROD and BFCOD activity, respectively. In vitro EROD activity inhibition with ellipticine showed tissue-specific inhibition, while ketoconazole decreased BFCOD activity by 50-98 % in all tissues. Further studies are needed to identify all CYP isoforms that are responsible for these activities and modes of regulation.

De facto reuse at the watershed scale: Seasonal changes, population contributions, instream flows and water quality hazards of human pharmaceuticals

With increasing population growth and climate change, de facto reuse practices are predicted to increase globally. We investigated a longitudinal gradient within the Uhlava River, a representative watershed, where de facto reuse is actively occurring, during Fall and Spring seasons when instream flows vary. We observed human pharmaceutical levels in the river to continuously increase from the mountainous areas upstream to downstream locations and a potable intake location, with the highest concentrations found in small tributaries. Significant relationship was identified between mass flow of pharmaceuticals and the size of human populations contributing to wastewater treatment plant discharges. Advanced ozonation and granular activated carbon filtration effectively removed pharmaceuticals from potable source waters. We observed a higher probability of encountering a number of targeted pharmaceuticals during colder Spring months when stream flows were elevated compared to warmer conditions with lower flows in the Fall despite a dilution paradigm routinely applied for surface water quality assessment and management efforts. Such observations translated to greater water quality hazards during these higher Spring flows. Future water monitoring efforts should account for periods when higher chemical uses occur, particularly in the face of climate change for regions experiencing population growth and de facto reuse.

High Resolution Mass Spectrometry Analysis of the Sertraline Residues Contained in the Tissues of Rainbow Trout Reared in Model Experimental Conditions

The growing consumption of pharmaceuticals in the human population and the insufficient efficiency of their elimination in waste water has a long-term negative impact on the environment of aquatic ecosystems, including the organisms that inhabit them. A significant contributor is the consumption of anti-depressants from the SSRI group, which corresponds to their increasing concentration in the environment. The aim of this work was to determine if antidepressant sertraline is able to be stored in fish organisms and to evaluate the content of residues in various body tissues. Rainbow trout (Oncorhynchuss mykkis) was selected as the test organism and was artificially exposed to the antidepressant for 1 month (concentrations 0; 4.2; 44 and 400 ng.g-1 sertraline in the feed). Liver, kidney, brain and muscle tissue biopsies samples were taken for analysis. Detection was performed using an Accela 1250 LC pump and an Accela autosampler coupled with a high-performance mass analyzer with a heated electrospray ionization source Q-Exactive Orbitrap, operating in positive ionization mode and in PRM mode (m/z 306.08108→275.03888 and 309.009991→275.03888 for sertraline and internal standard, respectively). The limit of quantification of the method was 0.1 ng.g-1 of sertraline and the calibration curve showed a good linearity up to 20 ng.g-1. From the collected data, amount of residues was found in the liver, kidney and brain. In contrast, the incidence of residues in muscle tissue was not detected in all groups, which is favorable from the point of view of fish meat consumption, by humans.

Water reuse and aquaculture: Pharmaceutical bioaccumulation by fish during tertiary treatment in a wastewater stabilization pond

With increasing demand for aquaculture products, water reuse is likely to increase for aquaculture operations around the world. Herein, wastewater stabilization ponds (WSP) represents low cost and sustainable treatment technologies to reduce nutrients and various contaminants of emerging concern from effluent. In the present study, we examined bioaccumulation of selected pharmaceuticals from several therapeutic classes by two important fish species in aquaculture with different feeding preferences (Cyprinus carpio and Sander lucioperca) and their common prey to test whether species specific accumulation occurs. Forty and nineteen from 66 selected pharmaceuticals and their metabolites were positively found in water and sediment samples, respectively from the representative WSP. After a six-month study, which corresponds to aquaculture operations, fourteen pharmaceuticals and their metabolites were detected (at a frequency of higher than 50% of samples) in at least one fish tissue collected from the WSP. We observed striking differences for species and organ specific BAFs among study compounds. Though muscle tissues consistently accumulated lower levels of the target analytes, several substances were elevated in brain, liver and kidney tissues (e.g., sertraline) of both species. Low residual concentrations of these target analytes in aquaculture products (fish fillets) suggest WSPs are promising to support the water-food nexus in aquaculture.

Human pharmaceuticals in marine mussels: Evidence of sneaky environmental hazard along Italian coasts

Despite the increasing interest for pharmaceuticals in the marine environment, their accumulation in wild organisms and consequent environmental hazards are still poorly known. The Mediterranean Sea is highly challenged by the density of coastal populations, large consumption of pharmaceuticals and their often limited removal by Wastewater Treatment Plants (WWTPs). In this respect, the present study aims to provide the first large-scale survey on the distribution of such contaminants of emerging concern in native mussels, Mytilus galloprovincialis from Italian coasts. Organisms were collected from 14 sites representative of relatively unpolluted marine waters along the Adriatic and Tyrrhenian Sea and analysed for 9 common pharmaceuticals including Non-Steroidal Anti-Inflammatory Drugs (NSAIDs: Diclofenac DIC, Ibuprofen IBU, Ketoprofen KET and Nimesulide NIM), the analgesic Acetaminophen AMP, the antiepileptic Carbamazepine CBZ, the antihypertensive Valsartan VAL, the anxiolytic Lormetazepam LOR and the antidepressant Paroxetine PAR. Results indicated the widespread occurrence of the majority of pharmaceuticals in mussel tissues: CBZ was measured in >90% of analysed samples, followed by VAL (>50%), PAR (>40%), and DIC (>30%), while only AMP and KET were never detected. Heterogeneous tissue concentrations ranged from a few units up to hundreds of ng/g (d.w.), while seasonal and interannual variability, investigated over 4 years, did not highlight any clear temporal trend. Limited differences obtained between the Adriatic and Tyrrhenian Sea, as well as coastal versus off-shore sampling sites, suggest that analysed levels of pharmaceuticals in mussels tissues should be considered as baseline concentrations for organisms collected in unpolluted areas of the Mediterranean. This study provided the first unambiguous evidence of the widespread occurrence of pharmaceuticals in marine mussels from Italian coasts, giving novel insights on the potential ecotoxicological hazard from such compounds in marine species.

Toxicity assessment of verapamil and its photodegradation products

Pathways of photochemical degradation of a cardiovascular drug verapamil under conditions relevant to natural waters and the toxicity of the photoproducts to Daphnia magna were investigated. Photodegradation was shown to proceed via photocatalysed mechanism. Two main photodegradation pathways were recognised: the first leading to hydroxylation at the methylamino position followed by splitting of verapamil molecule into two fragments, and the second providing the main active metabolite of verapamil, norverapamil, and a series of norverapamil isomers, followed again by their splitting at the amino group position. Twenty-two products of photodegradation were identified. Toxicity assays in sublethal concentrations of the parental drug, of the photoproduct mixture, and of norverapamil revealed no direct negative response in Daphnia magna to verapamil. On the other hand, photochemical products significantly lowered the number of juveniles, number of clutches, and body size of Daphnia. The exposition of Daphnia to norverapamil showed the same but even more pronounced effects than its exposition to the mixture of photoproducts, which leads to the conclusion that norverapamil is mainly responsible for the toxicity of photoproduct mixture and represents a noteworthy threat to aquatic invertebrates.

Biotransformation study of antidepressant sertraline and its removal during biological wastewater treatment

Sertraline is one of the most commonly prescribed antidepressants in the last few years. Therefore, it is not surprising that it is regularly detected in wastewaters, surface waters, sediments, biosolids and biota. Effluents from wastewater treatment plants are the main contributors to its presence in the environment. The presented study aims to elucidate the processes involved in its removal, concentrating mainly on sorption and biodegradation during wastewater treatment. We performed our laboratory scale experiments in two sets of experiments: 1) batch biodegradation and sorption experiments and 2) flow-through laboratory scale pilot wastewater treatment bioreactors. The batch experiments revealed that sorption to activated sludge was the leading removal process, eliminating up to 90% of sertraline present in the batches. Biodegradation was however the secondary removal process, influenced by the presence of alternative easily biodegradable carbon sources. We postulated chemical structures of ten detected biotransformation products. Among these, we propose the previously recognized metabolite norsertraline, sertraline ketone and hydroxy-sertraline. All the remaining biotransformation products are herein reported for the first time. The removal efficiency of approximately 94% was determined after the treatment in the flow-through bioreactors. To support our findings, we sampled influents and effluents from two wastewater treatment plants and untreated wastewater from a psychiatric hospital. Removal efficiencies of 81% and 77% were determined, and along with the parent compound sertraline, the presence of eight transformation products was confirmed in the actual wastewaters.

Psychoactive pharmaceuticals in aquatic systems: A comparative assessment of environmental monitoring approaches for water and fish

Environmental monitoring and surveillance studies of pharmaceuticals routinely examine occurrence of substances without current information on human consumption patterns. We selected 10 streams with diverse annual flows and differentially influenced by population densities to examine surface water occurrence and fish accumulation of select psychoactive medicines, for which consumption is increasing in the Czech Republic. We then tested whether passive sampling can provide a useful surrogate for exposure to these substances through grab sampling, body burdens of young of year fish, and tissue specific accumulation of these psychoactive contaminants. We identified a statistically significant (p < 0.05) relationship between ambient grab samples and passive samplers in these streams when psychoactive contaminants were commonly quantitated by targeted liquid chromatography with tandem mass spectrometry, though we did not observe relationships between passive samplers and tissue specific pharmaceutical accumulation. We further observed smaller lotic systems with elevated contamination when municipal effluent discharges from more highly populated cities contributed a greater extent of instream flows. These findings identify the importance of understanding age and species specific differences in fish uptake, internal disposition, metabolism and elimination of psychoactive drugs across surface water quality gradients.

Determination of citalopram in fish brain tissue: benefits of coupling laser diode thermal desorption with low- and high-resolution mass spectrometry

Recent state-of-the-art methods developed for the analysis of polar xenobiotics from different types of biological matrices usually employ liquid chromatography with mass spectrometry. However, there are limitations when a small amount of sample mass is available. For example, individual benthic invertebrates or fish tissue samples often weigh less than 100 mg (e.g., brain, liver) but are necessary to understand environmental fate and bioaccumulation dynamics. We developed ultra-fast methods based on a direct sample introduction technique. This included coupling laser diode thermal desorption with atmospheric pressure chemical ionization mass spectrometry (LDTD-APCI-MS). We then quantitated a common selective serotonin reuptake inhibitor (citalopram) in brain tissues of individual juvenile fish after in vivo exposure to environmentally relevant concentration. Two mass spectrometric methods based on low (LDTD-APCI-triple quadrupole (QqQ)-MS/MS) and high (LDTD-APCI-high-resolution product scan (HRPS)) resolutions were developed and evaluated. Individual instrument conditions were optimized to achieve an accurate and robust analytical method with minimum sample preparation requirements. We achieved very good recovery (97-108%) across the range of 1-100 ng g^-1 for LDTD-APCI-HRPS. LDTD-APCI-QqQ-MS/MS showed poorer performance due to interferences from the matrix at the lowest concentration level. LDTD-APCI ionization was successfully validated for analysis of non-filtered sample extracts. Evaluation of final methods was performed for a set of real fish brain samples, including comparison of LDTD-APCI-HRPS with a previously validated LC-heated electrospray ionization-HRPS method. This new LDTD-APCI-HRPS method avoids the chromatographic step and provides important benefits such as analysis of limited sample masses, lower total sample volume (typically μL), and reduction in analysis time per sample run to a few seconds. Graphical abstract.

Psychoactive compounds at environmental concentration alter burrowing behavior in the freshwater crayfish

Pharmaceutically active compounds (PhAC) have been increasingly detected in freshwater and marine waterbodies worldwide and are recognized as major emerging micropollutant threat to the aquatic environment. Despite their low concentrations in the environment, there is evidence of effects on non-target aquatic organisms in natural habitats. To assess the potential effects of PhACs on its burrowing behavior, we exposed the red swamp crayfish Procambarus clarkii to methamphetamine or tramadol at the environmentally relevant concentration of 1 μg/L. Methamphetamine-exposed females constructed burrows of lower depth and volume relative to individual weight than did controls. Tramadol-exposed females consistently exhibited a tendency for smaller burrows, but this difference was not significant. Exposed males showed a non-significant tendency to excavate larger burrows compared with the control. Control and tramadol-treated females maintained the natural tendency of constructing relatively deeper and/or larger-volume burrows compared with males. This sex-related pattern was not detected in the methamphetamine group. The rate of human therapeutic PhAC usage is relatively stable year-round, and impacts on crayfish burrowing can be particularly damaging during periods of drought, when the dilution of waste waters is reduced, and burrowing becomes a critical survival strategy. Our results suggest that an increasingly broad range of environmental impacts of PhACs on non-target organisms can be expected in natural ecosystems.