Application of prioritization approaches to optimize environmental monitoring and testing of pharmaceuticals

Current uncertainties and challenges of publicly available pharmaceutical environmental risk assessment data

Pharmaceutical residues are widely detected in aquatic environment worldwide mainly arising from human excretions in sewage systems. Presently, publicly available, high quality environmental risk assessment (ERA) data for pharmaceuticals are limited. However, databases like the Swedish Fass offer valuable resources aiding healthcare professionals and environmental scientists in identifying substances of significant concern. In this review, we provide a concise overview of the regulatory ERA process for medicinal products intended for human use. We explore its key assumptions and uncertainties using a subset of 37 pharmaceuticals. First, we compare the consistency of their predicted no-effect concentrations reported in the Fass database with those by marketing authorisation holders. Second, we compare the predicted environmental concentrations (PEC) calculated based on sales data between European and national drug consumption statistics as well as with measured environmental concentrations (MEC), to demonstrate their impact on the regional risk quotients. Finally, we briefly discuss the prevailing uncertainties and challenges of current ecotoxicity testing, especially outcomes of chronic and nonlethal effects.

Using the fish plasma model to evaluate potential effects of pharmaceuticals in effluent from a large urban wastewater treatment plant

Several pharmaceuticals and personal care products (PPCPs) were evaluated using the fish plasma model (FPM) for juvenile Chinook salmon exposed to effluent from a large urban wastewater treatment plant. The FPM compares fish plasma concentrations to therapeutic values determined in human plasma as an indication of potential adverse effects. We used human Cmax values, which are the maximum plasma concentration for a minimum therapeutic dose. Observed and predicted plasma concentrations from juvenile Chinook salmon exposed to a dilution series of whole wastewater effluent were compared to 1%Cmax values to determine Response Ratios (RR) ([plasma]/1%Cmax) for assessment of possible adverse effects. Several PPCPs were found to approach or exceed an RR of 1, indicating potential effects in fish. We also predicted plasma concentrations from measured water concentrations and determined that several of the values were close to or below the analytical reporting limit (RL) indicating potential plasma concentrations for a large number of PPCPs that were below detection. Additionally, the 1%Cmax was less than the RL for several analytes, which could impede predictions of possible effect concentrations. A comparison of observed and predicted plasma concentrations found that observed values were frequently much higher than values predicted with water concentrations, especially for low log10Dow compounds. The observed versus predicted values using the human volume of distribution (Vd), were generally much closer in agreement. These data appear to support the selection of whole-body concentrations to predict plasma values, which relies more on estimating simple partitioning within the fish instead of uptake via water. Overall, these observations highlight the frequently underestimated predicted plasma concentrations and potential to cause adverse effects in fish. Using measured plasma concentrations or predicted values from whole-body concentrations along with improved prediction models and reductions in analytical detection limits will foster more accurate risk assessments of pharmaceutical exposure for fish.

Selection of pharmaceuticals of concern in reclaimed water for crop irrigation in the Mediterranean area

The reuse of reclaimed water in agriculture is being fostered in areas suffering from water scarcity. However, water pollutants can compromise food safety and pose a risk for the environment. This study aims to select the pharmaceutical compounds worth monitoring and investigating when reclaimed water is used for tomato and lettuce irrigation. A comprehensive study was first conducted to identify the pharmaceuticals frequently detected in secondary wastewater effluents in Catalonia (Northeast Spain). Priority pharmaceuticals were further selected based on their occurrence in secondary effluents, persistence (removal in conventional treatment), bioaccumulation potential, toxicity for aquatic organisms, and the risks they pose to the terrestrial environment and human health (through the consumption of crops). Out of the 47 preselected priority compounds, six could pose a risk to organisms living in soil irrigated with reclaimed water and seven could be potentially taken up by the crops. Nonetheless, no risk for human consumption was foreseen.

Cross-Species Extrapolation of Biological Data to Guide the Environmental Safety Assessment of Pharmaceuticals-The State of the Art and Future Priorities

The extrapolation of biological data across species is a key aspect of biomedical research and drug development. In this context, comparative biology considerations are applied with the goal of understanding human disease and guiding the development of effective and safe medicines. However, the widespread occurrence of pharmaceuticals in the environment and the need to assess the risk posed to wildlife have prompted a renewed interest in the extrapolation of pharmacological and toxicological data across the entire tree of life. To address this challenge, a biological "read-across" approach, based on the use of mammalian data to inform toxicity predictions in wildlife species, has been proposed as an effective way to streamline the environmental safety assessment of pharmaceuticals. Yet, how effective has this approach been, and are we any closer to being able to accurately predict environmental risk based on known human risk? We discuss the main theoretical and experimental advancements achieved in the last 10 years of research in this field. We propose that a better understanding of the functional conservation of drug targets across species and of the quantitative relationship between target modulation and adverse effects should be considered as future research priorities. This pharmacodynamic focus should be complemented with the application of higher-throughput experimental and computational approaches to accelerate the prediction of internal exposure dynamics. The translation of comparative (eco)toxicology research into real-world applications, however, relies on the (limited) availability of experts with the skill set needed to navigate the complexity of the problem; hence, we also call for synergistic multistakeholder efforts to support and strengthen comparative toxicology research and education at a global level. Environ Toxicol Chem 2024;43:513-525. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

What Approaches Should be Used to Prioritize Pharmaceuticals and Personal Care Products for Research on Environmental and Human Health Exposure and Effects?

Pharmaceuticals and personal care products (PPCPs) are released from multiple anthropogenic sources and thus have a ubiquitous presence in the environment. The environmental exposure and potential effects of PPCPs on biota and humans has aroused concern within the scientific community and the public. Risk assessments are commonly conducted to evaluate the likelihood of chemicals including PPCPs that pose health threats to organisms inhabiting various environmental compartments and humans. Because thousands of PPCPs are currently used, it is impractical to assess the environmental risk of all of them due to data limitations; in addition, new PPCPs are continually being produced. Prioritization approaches, based either on exposure, hazard, or risk, provide a possible means by which those PPCPs that are likely to pose the greatest risk to the environment are identified, thereby enabling more effective allocation of resources in environmental monitoring programs in specific geographical locations and ecotoxicological investigations. In the present review, the importance and current knowledge concerning PPCP occurrence and risk are discussed and priorities for future research are proposed, in terms of PPCP exposure (e.g., optimization of exposure modeling in freshwater ecosystems and more monitoring of PPCPs in the marine environment) or hazard (e.g., differential risk of PPCPs to lower vs. higher trophic level species and risks to human health). Recommended research questions for the next 10 years are also provided, which can be answered by future studies on prioritization of PPCPs. Environ Toxicol Chem 2024;43:488-501. © 2022 SETAC.

The Effect of Polymerization Techniques on the Creation of Molecularly Imprinted Polymer Sensors and Their Application on Pharmaceutical Compounds

Molecularly imprinted polymers (MIPs) have become more prevalent in fabricating sensor applications, particularly in medicine, pharmaceuticals, food quality monitoring, and the environment. The ease of their preparation, adaptability of templates, superior affinity and specificity, improved stability, and the possibility for downsizing are only a few benefits of these sensors. Moreover, from a medical perspective, monitoring therapeutic medications and determining pharmaceutical compounds in their pharmaceutical forms and biological systems is very important. Additionally, because medications are hazardous to the environment, effective, quick, and affordable determination in the surrounding environment is of major importance. Concerning a variety of performance criteria, including sensitivity, specificity, low detection limits, and affordability, MIP sensors outperform other published technologies for analyzing pharmaceutical drugs. MIP sensors have, therefore, been widely used as one of the most crucial techniques for analyzing pharmaceuticals. The first part of this review provides a detailed explanation of the many polymerization techniques that were employed to create high-performing MIP sensors. In the subsequent section of the review, the utilization of MIP-based sensors for quantifying the drugs in their pharmaceutical preparation, biological specimens, and environmental samples are covered in depth. Finally, a critical evaluation of the potential future research paths for MIP-based sensors clarifies the use of MIP in pharmaceutical fields.

Development of a Lymnaea stagnalis embryo bioassay for chemicals hazard assessment

The validation of high-throughput toxicity tests with invertebrate species is a key priority to improve hazard assessment of new chemicals and increase the available test guidelines with organisms from a representative set of taxa. This work aimed to contribute to the validation of an embryo test with the freshwater gastropod Lymnaea stagnalis, which has been identified by Organization for Economic Co-operation and Development (OECD) as a potential invertebrate test model, and provide the basis for such an endeavor. Recently, a L. stagnalis reproductive test was standardized by the OECD. However, to encompass the entire life cycle, it is crucial to addresses embryogenic development - a phase highly susceptible to various anthropogenic chemicals, which is covered in the proposed methodology. The approach used in the present study is in line with the OECD guidelines and other published studies, namely the Detailed Review Paper (DRP) on Mollusks life-cycle toxicity testing. Here, the assay quality criteria such as basal mortality and abnormality rates, development, growth and hatching rates, the appropriated testing media, and the optimal assay duration were investigated. Cadmium was chosen as the positive test substance, due to the available data and the verified model sensitivity to this compound, namely in the OECD reproductive test validation process. The obtained data demonstrate that L. stagnalis embryogenesis using the developed methodology is highly sensitive to cadmium. High concentration-response correlation was observed using this reference compound, the EC10 and EC50 for growth are 13.57 and 21.84 μg/L, respectively, after 168 h of exposure. The development EC's 10 and 50 were 15.75 and 38.66 μg/L, respectively, after 240 h. This demonstrates the model sensitivity to this compound when compared with other embryo test models, as well as the model sensitivity during the embryogenesis, if compared with the adult stage. Further, given the determined sensitivity parameters, and incubation times, the test can be performed at 240 h as over 95 % of the control embryos were hatched and no further significant changes in the exposure groups were determined. Overall, the findings of the present study demonstrate that the embryo test with L. stagnalis has potential to high-throughput testing and the model has a high sensitivity to cadmium during this life cycle period. The background data provide by this study will be essential to foster the future standardization of this assay.

Designing greener active pharmaceutical ingredients: Insights from pharmaceutical industry into drug discovery and development

Active pharmaceutical ingredients (APIs), their metabolites and transformation products (TPs) are found as pollutants in the environment. They can impact human and environmental health. To address this issue, an efficient, long-term prevention strategy could be the design of APIs that have less impact on the natural environment, i.e. the design of greener APIs, by the implementation of environmental parameters into the drug discovery and development process (also abbreviated R&D for 'research and development'). Our study aimed to evaluate the feasibility of the design of greener APIs based on insights from drug design experts working in large, research-based pharmaceutical companies. The feasibility evaluation also identified needs and incentives for process modification. For this purpose, 30 R&D and environmental experts from seven globally active pharmaceutical companies were interviewed along a structured questionnaire. Main findings are that the interviewed experts saw manifold opportunities to include properties rendering APIs greener in different stages along the R&D process. This implementation would be favoured by the fact that the pharmaceutical R&D process is very flexible and relies on balancing multiple parameters. Furthermore, some API properties that reduce environmental risks were considered compatible with common desirable properties for application. Environmental properties should be considered early during R&D, i.e. when molecules are screened and optimized. It has been found that availability of suitable in silico models and in vitro assays is crucial for this environmental consideration. Their attributes, e.g. throughput and costs, determine at which process stage they can be successfully applied. An intensified exchange between R&D and environmental experts within and outside companies would push the industrial application of the benign by design approach for APIs forward. Collaboration across pharmaceutical companies, authorities, and academia is seen as highly promising in this respect. Financial, social, and regulatory incentives would support future design of greener APIs.

Prioritisation of data-poor pharmaceuticals for empirical testing and environmental risk assessment

There are more than 3,500 active pharmaceutical ingredients (APIs) on the global market for human and veterinary use. Residues of these APIs eventually reach the aquatic environment. Although an environmental risk assessment (ERA) for marketing authorization applications of medicinal products is mandatory in the European Union since 2006, an ERA is lacking for most medicines approved prior to 2006 (legacy APIs). Since it is unfeasible to perform extensive ERA tests for all these legacy APIs, there is a need for prioritization of testing based on the limited data available. Prioritized APIs can then be further investigated to estimate their environmental risk in more detail. In this study, we prioritized more than 1,000 APIs used in Europe based on their predicted risk for aquatic freshwater ecosystems. We determined their risk by combining an exposure estimate (Measured or Predicted Environmental Concentration; MEC or PEC, respectively) with a Predicted No Effect Concentration (PNEC). We developed several procedures to combine the limited empirical data available with in silico data, resulting in multiple API rankings varying in data needs and level of conservativeness. In comparing empirical with in silico data, our analysis confirmed that the PEC estimated with the default parameters used by the European Medicines Agency often - but not always - represents a worst-case scenario. Comparing the ecotoxicological data for the three main taxonomic groups, we found that fish represents the most sensitive species group for most of the APIs in our list. We furthermore show that the use of in silico tools can result in a substantial underestimation of the ecotoxicity of APIs. After combining the different exposure and effect estimates into four risk rankings, the top-ranking APIs were further screened for availability of ecotoxicity data in data repositories. This ultimately resulted in the prioritization of 15 APIs for further ecotoxicological testing and/or exposure assessment.

Pharmaceutically active compounds (PhACs) in surface water: Occurrence, trends and risk assessment in the Tagus River Basin (Spain)

In this study, the presence of 23 pharmaceutically active compounds (PhACs) including antibiotics, analgesics, anti-inflammatories, psychiatric and cardiovascular drugs, antifungals and metabolites was investigated in surface waters. A total of 89 samples were collected during 3 years (2020, 2021 and 2022) from a European representative river basin (Tagus, Spain). To elucidate PhAC potential sources, sampling points located in areas with low, median and high anthropogenic influence were selected. The analytical method based on solid phase extraction (SPE) followed by UHPLC-MS/MS analysis was validated meeting SANTE/2020/12830 and SANTE/12682/2019 performance criteria. PhACs were quantified above limits of quantification (LOQs) in 96 % of water samples, being the antihypertensives valsartan (648 ng/L, 87 % quantification frequency) and irbesartan (390 ng/L, 75 %) and the antidepressant o-desmethylvenlafaxine (495 ng/L, 76 %) the predominant pollutants. The rest of the target PhACs showed median concentrations between 4 and 172 ng/L with quantification frequencies ranging from 35 to 75 %. ∑PhAC concentrations did not show temporal or seasonal trends. However, valsartan and naproxen presented lower levels in drier (spring and summer) compared to the wetter. Source identification revealed a clear anthropogenic origin since concentrations obtained in highly populated areas were statistically higher (p < 0.01) than those quantified in sparsely populated ones. This finding was also confirmed by calculating PhACs mass flow rates, which ranged between 1.4 and 235 kg/y. Finally, data generated were used to estimate the potential risk to the aquatic ecosystem for three trophic levels (phototrophic, invertebrate and vertebrate organisms). Risk quotient ratios (RQs) were calculated for all PhACs at the median (P50) and worst-case (max) scenarios. Up to 7 PhACs (acetaminophen, carbamazepine, gemfibrozil, ibuprofen, irbesartan, ketoprofen and venlafaxine) showed high risk for the highest trophic level (fish) in >45 % of investigated locations.

Water, Water Everywhere, but Every Drop Unique: Challenges in the Science to Understand the Role of Contaminants of Emerging Concern in the Management of Drinking Water Supplies

The protection and management of water resources continues to be challenged by multiple and ongoing factors such as shifts in demographic, social, economic, and public health requirements. Physical limitations placed on access to potable supplies include natural and human-caused factors such as aquifer depletion, aging infrastructure, saltwater intrusion, floods, and drought. These factors, although varying in magnitude, spatial extent, and timing, can exacerbate the potential for contaminants of concern (CECs) to be present in sources of drinking water, infrastructure, premise plumbing and associated tap water. This monograph examines how current and emerging scientific efforts and technologies increase our understanding of the range of CECs and drinking water issues facing current and future populations. It is not intended to be read in one sitting, but is instead a starting point for scientists wanting to learn more about the issues surrounding CECs. This text discusses the topical evolution CECs over time (Section 1), improvements in measuring chemical and microbial CECs, through both analysis of concentration and toxicity (Section 2) and modeling CEC exposure and fate (Section 3), forms of treatment effective at removing chemical and microbial CECs (Section 4), and potential for human health impacts from exposure to CECs (Section 5). The paper concludes with how changes to water quantity, both scarcity and surpluses, could affect water quality (Section 6). Taken together, these sections document the past 25 years of CEC research and the regulatory response to these contaminants, the current work to identify and monitor CECs and mitigate exposure, and the challenges facing the future.

Are early and young life stages of fish affected by paroxetine? A case study with Danio rerio

Paroxetine (PAR) is a selective serotonin reuptake inhibitor (SSRI) antidepressant increasingly detected in surface waters worldwide. Its environmental presence raises concerns about the potential detrimental effects on non-target organisms. Thus, this study aimed to increase knowledge on PAR's potential environmental impacts, assessing the effects of commercial formulation (PAR-c) and active ingredient (PAR-a) on fish. Therefore, the short-term exposure effects of PAR-c and PAR-a were assessed on zebrafish (Danio rerio) embryos/larvae to determine the most toxic formulation [through median lethal (LC50) and effective concentrations (EC50)]. PAR-c and PAR-a induced morphological abnormalities (scoliosis) in a dose-dependent manner from 96 hours post-fertilization onwards, suggesting the involvement of a fully functional biotransformation system. As PAR-c exhibited higher toxicity, it was selected to be tested in the subsequent stage (juvenile stage), which was more sensitive (lower LC50). PAR-c significantly decreased fish swimming activity and disrupted fish stress response. Overall, the results highlight the ability of PAR-c to adversely affect fish swimming performance, an effect that persisted even after exposure ceases (21-day depuration), suggesting that PAR-c may impair individual fitness.

Uptake of Pharmaceuticals by Crops: A Systematic Review and Meta-analysis

Studies on the uptake of pharmaceuticals from soils into crops were first conducted in the 2000s. Since then a wealth of such data has been generated, but to the best of our knowledge, these studies have not been systematically reviewed. We present a quantitative, systematic review of empirical data on the uptake of pharmaceuticals into crops. We developed a custom-made relational database on plant uptake of pharmaceuticals that contained details of the experimental design and associated results from 150 articles, spanning 173 pharmaceuticals, 78 study crops, and 8048 unique measurements. Analysis of the data in the database showed clear trends in experimental design, with lettuce being the most studied crop and carbamazepine and sulfamethoxazole being the most studied pharmaceuticals. Pharmaceutical properties were found to create the greatest range in uptake concentrations of any single variable studied. Uptake concentrations were also found to vary between crops, with relatively high uptake concentrations identified in cress, lettuce, rice, and courgette crops. An understanding of the influence of soil properties on pharmaceutical uptake was limited by a lack of information on key soil properties across the published literature. The data comparisons were inhibited by differences in quality of the different studies. Moving forward, a framework for best practice in this field is needed to maximize the value and further applications of the data produced. Environ Toxicol Chem 2023;42:2091-2104. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Predicting Environmental Risks of Pharmaceuticals from Wholesale Data: An Example from Norway

Environmental risk assessment (ERA) of pharmaceuticals relies on available measured environmental concentrations, but often such data are sparse. Predicted environmental concentrations (PECs), calculated from sales weights, are an attractive alternative but often cover only prescription sales. We aimed to rank, by environmental risk in Norway, approximately 200 active pharmaceutical ingredients (APIs) over 2016-2019, based on sales PECs. To assess the added value of wholesale and veterinary data, we compared exposure and risk predictions with and without these additional sources. Finally, we aimed to characterize the persistence, mobility, and bioaccumulation of these APIs. We compared our PECs to available Norwegian measurements, then, using public predicted-no-effect concentrations, we calculated risk quotients (RQs) and appended experimental and predicted persistence and bioaccumulation. Our approach overestimated environmental concentrations compared with measurements for 18 of 20 APIs with comparable predictions and measurements. Seventeen APIs had mean RQs >1, indicating potential risk, while the mean RQ was 2.05 and the median 0.001, driven by sex hormones, antibiotics, the antineoplastic abiraterone, and common painkillers. Some high-risk APIs were also potentially persistent or bioaccumulative (e.g., levonorgestrel [RQ = 220] and ciprofloxacin [RQ = 56]), raising the possibility of impacts beyond their RQs. Exposure and risk were also calculated with and without over-the-counter sales, showing that prescriptions explained 70% of PEC magnitude. Likewise, human sales, compared with veterinary, explained 85%. Sales PECs provide an efficient option for ERA, designed to overestimate compared with analytical techniques and potentially held back by limited data availability and an inability to quantify uncertainty but, nevertheless, an ideal initial approach for identification and ranking of risks. Environ Toxicol Chem 2023;42:2253-2270. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Ranking the risks of eighty pharmaceuticals in surface water of a megacity: A multilevel optimization strategy

Pharmaceuticals in freshwater posed ecological risks to aquatic ecosystem, however, most risk assessments of pharmaceuticals were conducted at screening level, which were limited by the availability of the toxicity data. In this study, risks of 80 pharmaceuticals including 35 antibiotics, 13 antiviral drugs, 13 illicit drugs, and 19 antidepressants in surface water of Beijing were assessed with a proposed multilevel environmental risk optimization strategy. Target pharmaceuticals were detected in surface water samples with the detection frequency from 1.7 % to 100 % and the total concentrations from 31.1 ng/L to 2708 ng/L. Antiviral drugs were the dominant pharmaceuticals. Preliminary screening-level risk assessment indicated that 20 pharmaceuticals posed low to high risks with risk quotient from 0.14 (chloroquine diphosphate) to 27.8 (clarithromycin). Thirteen pharmaceuticals were recognized with low to high risks by an optimized risk assessment method. Of them, the refined probabilistic risk assessment of joint probability curves coupling with a quantitative structure activity relationship-interspecies correlation estimation (QSAR-ICE) model was applied. Clarithromycin, erythromycin and ofloxacin were identified to pose low risks with maximum risk products (RP) of 1.23 %, 0.41 % and 0.35 %, respectively, while 10 pharmaceuticals posed de minimis risks. Structural equation modeling disclosed that human land use and climate conditions influenced the risks of pharmaceuticals by indirectly influencing the concentrations of pharmaceuticals. The results indicated that the multilevel strategy coupling with QSAR-ICE model was appropriate and effective for screening priority pollutants, and the strategy can be used to prioritize pharmaceuticals and other emerging contaminants in the aquatic environment.

Prioritization of pharmaceuticals and personal care products in the surface waters of Korea: Application of an optimized risk-based methods

The occurrence of PPCPs in aquatic environments and their potential adverse effects on aquatic organisms have raised worldwide concerns. To address this issue, a study was conducted to analyze 137 selected PPCPs in Korean surface waters, and an optimized risk-based prioritization was performed. The results revealed that 120 PPCPs were detected, with 98 quantified at concentrations ranging from few ng/L to 42,733 ng/L for metformin. The 95% upper confidence limit (UCL95) of the mean value of the measured environmental concentration (MEC) for Metformin was about eight times higher than the second highest compound, dimethyl phthalate, indicating that antidiabetic groups had the highest concentration among the therapeutic groups. An optimized risk-based prioritization was then assessed based on the multiplication of two indicators, the Frequency of Exceedance and the Extent of Exceedance of Predicted No-Effect Concentrations (PNECs), which can be calculated using the traditional risk quotient (RQ) approach. The study found that clotrimazole had the highest risk quotient value of 17.4, indicating a high risk to aquatic organisms, with seven and 13 compounds showing RQ values above 1 and 0.1, respectively. After considering the frequency of exceedance, clotrimazole still had the highest novel risk quotient (RQ_f) value of 17.4, with 99.6% of its MECs exceeding PNECs. However, the number of compounds with RQ_f values above 1 decreased from seven to five, with cetirizine and flubendazole being excluded. Furthermore, only 10 compounds exhibited RQ_f values above 0.1. The study also observed significant differences in the results between risk-based and exposure-based prioritization methods, with only five compounds, cetirizine, olmesartan, climbazole, sulfapyridine, and imidacloprid, identified in both methods. This finding highlights the importance of considering multiple methods for prioritizing chemicals, as different approaches may yield different results.

Predicted Environmental Risk Assessment of Antimicrobials with Increased Consumption in Portugal during the COVID-19 Pandemic; The Groundwork for the Forthcoming Water Quality Survey

The environmental release of antimicrobial pharmaceuticals is an imminent threat due to ecological impacts and microbial resistance phenomena. The recent COVID-19 outbreak will likely lead to greater loads of antimicrobials in the environment. Thus, identifying the most used antimicrobials likely to pose environmental risks would be valuable. For that, the ambulatory and hospital consumption patterns of antimicrobials in Portugal during the COVID-19 pandemic (2020–2021) were compared with those of 2019. A predicted risk assessment screening approach based on exposure and hazard in the surface water was conducted, combining consumption, excretion rates, and ecotoxicological/microbiological endpoints in five different regions of Portugal. Among the 22 selected substances, only rifaximin and atovaquone demonstrated predicted potential ecotoxicological risks for aquatic organisms. Flucloxacillin, piperacillin, tazobactam, meropenem, ceftriaxone, fosfomycin, and metronidazole showed the most significant potential for antibiotic resistance in all analysed regions. Regarding the current screening approach and the lack of environmental data, it is advisable to consider rifaximin and atovaquone in subsequent water quality surveys. These results might support the forthcoming monitorisation of surface water quality in a post-pandemic survey.

Long and Short Duration Exposures to the Selective Serotonin Reuptake Inhibitors (SSRIs) Fluoxetine, Paroxetine and Sertraline at Environmentally Relevant Concentrations Lead to Adverse Effects on Zebrafish Behaviour and Reproduction

Selective serotonin reuptake inhibitors (SSRIs) are currently the most prescribed class of psychotropic medications. Their increased global manufacture and use have become growing concerns for aquatic toxicologists and environmental biologists, who assess both the direct and indirect effects of substances on the environment and on human health. In order to assess the potential impact of environmentally relevant levels of SSRIs on fish development, behaviour and reproduction, we exposed juvenile and adult zebrafish to a select group of SSRIs using two separate exposure paradigms. In the first paradigm, juvenile zebrafish were exposed to Fluoxetine (Prozac), Paroxetine (Paxil), Sertraline (Zoloft) or a mixture of the three beginning at environmentally relevant levels (10 µg/L) for 135 days (long-term exposure) beginning at 5 days post fertilization (dpf). In the second paradigm, adult zebrafish were exposed to matching concentrations of the same SSRIs for 35 days (short-term exposure). The long-term exposure paradigm proved to have little to no overt effect on growth or development at sub-lethal concentrations (10 and 100 µg/L). However, both the stress/anxiety response (novel tank tests) and reproduction (fecundity and fertility) were dramatically reduced. Importantly, the short-term exposure of reproductively mature fish led to similar adverse effects on both the stress response and reproduction. Following both the short and long duration exposure paradigms, a 2-week washout period led to a small reduction in the adverse effects. These findings highlight the potential for SSRIs to negatively impact population dynamics in zebrafish and may be of particular value should they be found in other fish species in the environment.

Minimizing Experimental Testing on Fish for Legacy Pharmaceuticals

There was no regulatory requirement for ecotoxicological testing of human pharmaceuticals authorized before 2006, and many of these have little or no data available to assess their environmental risk. Motivated by animal welfare considerations, we developed a decision tree to minimize in vivo fish testing for such legacy active pharmaceutical ingredients (APIs). The minimum no observed effect concentration (NOECmin, the lowest NOEC from chronic Daphnia and algal toxicity studies), the theoretical therapeutic water concentration (TWC, calculated using the fish plasma model), and the predicted environmental concentration (PEC) were used to derive API risk quotients (PEC/NOECmin and PEC/TWC). Based on a verification data set of 96 APIs, we show that by setting a threshold value of 0.001 for both risk quotients, the need for in vivo fish testing could potentially be reduced by around 35% without lowering the level of environmental protection. Hence, for most APIs, applying an assessment factor of 1000 (equivalent to the threshold of 0.001) to NOECmin substituted reliably for NOECfish, and TWC acted as an effective safety net for the others. In silico and in vitro data and mammalian toxicity data may further support the final decision on the need for fish testing.

Is water quality in British rivers "better than at any time since the end of the Industrial Revolution"?

We explore the oft-repeated claim that river water quality in Great Britain is "better now than at any time since the Industrial Revolution". We review available data and ancillary evidence for seven different categories of water pollutants: (i) biochemical oxygen demand (BOD) and ammonia; (ii) heavy metals; (iii) sewage-associated organic pollutants (including hormone-like substances, personal care product and pharmaceutical compounds); (iv) macronutrients (nitrogen and phosphorus); (v) pesticides; (vi) acid deposition and (vii) other variables, including natural organic matter and pathogenic micro-organisms. With a few exceptions, observed data are scarce before 1970. However, we can speculate about some of the major water quality pressures which have existed before that. Point-source pollutants are likely to have increased with population growth, increased connection rates to sewerage and industrialisation, although the increased provision of wastewater treatment during the 20th century will have mitigated this to some extent. From 1940 to the 1990s, pressures from nutrients and pesticides associated with agricultural intensification have increased in many areas. In parallel, there was an increase in synthetic organic compounds with a "down-the-drain" disposal pathway. The 1990s saw general reductions in mean concentrations of metals, BOD and ammonia (driven by the EU Urban Waste Water Treatment Directive), a levelling out of nitrate concentrations (driven by the EU Nitrate Directive), a decrease in phosphate loads from both point-and diffuse-sources and some recovery from catchment acidification. The current picture is mixed: water quality in many rivers downstream of urban centres has improved in sanitary terms but not with respect to emerging contaminants, while river quality in catchments with intensive agriculture is likely to remain worse now than before the 1960s. Water quality is still unacceptably poor in some water bodies. This is often a consequence of multiple stressors which need to be better-identified and prioritised to enable continued recovery.

Distribution and ecological risks of pharmaceuticals and personal care products with different anthropogenic stresses in a coastal watershed of China

The occurrences of pharmaceutical and personal care products (PPCPs) in both freshwater and sea have been widely reported. However, pollution control requires further information on riverine discharges with influence of land-based activities and associated risks to estuarine ecosystems. This study investigated the spatial occurrences and the relationship to sociodemographic parameters of 30 PPCPs in 67 rivers along the Bohai coastal region. The results showed that PPCPs were mainly deposited in aquatic phase, and the partitioning coefficient between water and sediment was highly determined by chemical properties. The levels of 30 PPCPs in rivers ranged from 8.33 to 894.48 ng/L, showing a large variance among regions. Caffeine, sulfamethoxazole, sulfamethazine, ofloxacin, anhydro-erythromycin, and trimethoprim were found to be the major pollutants. Multivariable analysis method was used to assess the correlation of PPCPs markers to socio-economic parameters. The results indicated that domestic emissions contributed most to the occurrences of PPCPs in the riverine water. Risk assessment result indicated that sulfamethoxazole, caffeine, tetracycline, and carbamazepine ranked top four with the highest risks to the most sensitive aquatic organisms. The results identified caffeine and carbamazepine with high detection frequency and concentration as the priority chemicals, while sulfamethoxazole and erythromycin should also be concerned due to their potential threats in specific rivers. This study provides valuable information for pollution control over PPCPs riverine discharges in estuarine regions.

Assessment of the Potential Ecotoxicological Effects of Pharmaceuticals in the World's Rivers

During their production, use, and disposal, active pharmaceutical ingredients (APIs) are released into aquatic systems. Because they are biologically active molecules, APIs have the potential to adversely affect nontarget organisms. We used the results of a global monitoring study of 61 APIs alongside available ecotoxicological and pharmacological data to assess the potential ecotoxicological effects of APIs in rivers across the world. Approximately 43.5% (461 sites) of the 1052 sampling locations monitored across 104 countries in a recent global study had concentrations of APIs of concern based on apical, nonapical, and mode of action-related endpoints. Approximately 34.1% of the 137 sampling campaigns had at least one location where concentrations were of ecotoxicological concern. Twenty-three APIs occurred at concentrations exceeding "safe" concentrations, including substances from the antidepressant, antimicrobial, antihistamine, β-blocker, anticonvulsant, antihyperglycemic, antimalarial, antifungal, calcium channel blocker, benzodiazepine, painkiller, progestin, and lifestyle compound classes. At the most polluted sites, effects are predicted on different trophic levels and on different endpoint types. Overall, the results show that API pollution is a global problem that is likely negatively affecting the health of the world's rivers. To meet the United Nations' Sustainable Development Goals, work is urgently needed to tackle the problem and bring concentrations down to an acceptable level. Environ Toxicol Chem 2022;41:2008-2020. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Screen-Printed Voltammetric Sensors-Tools for Environmental Water Monitoring of Painkillers

The dynamic production and usage of pharmaceuticals, mainly painkillers, indicates the growing problem of environmental contamination. Therefore, the monitoring of pharmaceutical concentrations in environmental samples, mostly aquatic, is necessary. This article focuses on applying screen-printed voltammetric sensors for the voltammetric determination of painkillers residues, including non-steroidal anti-inflammatory drugs, paracetamol, and tramadol in environmental water samples. The main advantages of these electrodes are simplicity, reliability, portability, small instrumental setups comprising the three electrodes, and modest cost. Moreover, the electroconductivity, catalytic activity, and surface area can be easily improved by modifying the electrode surface with carbon nanomaterials, polymer films, or electrochemical activation.

Ecological Risk Assessment of Pharmaceuticals in the Transboundary Vecht River (Germany and The Netherlands)

Millions of people rely on active pharmaceutical ingredients (APIs) to prevent and cure a wide variety of illnesses in humans and animals, which has led to a steadily increasing consumption of APIs across the globe and concurrent releases of APIs into the environment. In the environment, APIs can have a detrimental impact on wildlife, particularly aquatic wildlife. Therefore, it is essential to assess their potential adverse effects to aquatic ecosystems. The European Water Framework Directive sets out that risk assessment should be performed at the catchment level, crossing borders where needed. The present study defines ecological risk profiles for surface water concentrations of 8 APIs (carbamazepine, ciprofloxacin, cyclophosphamide, diclofenac, erythromycin, 17α-ethinylestradiol, metformin, and metoprolol) in the Vecht River, a transboundary river that crosses several German and Dutch regions. Ultimately, 3 main goals were achieved: 1) the geo-referenced estimation of API concentrations in surface water using the geography-referenced regional exposure assessment tool for European rivers; 2) the derivation of new predicted-no-effect concentrations for 7 of the studied APIs, of which 3 were lower than previously derived values; and 3) the creation of detailed spatially explicit ecological risk profiles of APIs under 2 distinct water flow scenarios. Under average flow conditions, carbamazepine, diclofenac, and 17α-ethinylestradiol were systematically estimated to surpass safe ecological concentration thresholds in at least 68% of the catchment's water volume. This increases to 98% under dry summer conditions. Environ Toxicol Chem 2022;41:648-662. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Evidence for Specific Receptor-Mediated Toxicity of Pharmaceuticals in Aquatic Organisms Derived from Acute and Chronic Standard Endpoints

The toxicity of 17 active pharmaceutical ingredients (APIs) was investigated using standardized acute and chronic tests with Daphnia magna and 2 algae species. Chronic toxicity was generally greater for Daphnia than for algae. Compilation of additional data resulted in 100 APIs for which the acute-to-chronic ratio (ACR) was determined for Daphnia. The frequency of high ACRs (~20% with ACRs > 100) indicates that specific receptor-mediated toxicity toward D. magna is rather common among APIs. The 11 APIs with ACRs > 1000 included lipid-modifying agents, immunosuppressants, antibiotics, antineoplastics, antiobesics, antivirals, and antihistamines. There was no consistent association between ACR and chronic toxicity, ionization status, or lipophilicity. High ACRs were not exclusively associated with the presence of orthologs of the pharmacological target in Daphnia. Statins, acetylcholinesterase inhibitors, and antihistamines are discussed in more detail regarding the link between targets and toxic mode of action. For acetylcholinesterase inhibitors, receptor-mediated toxicity was already apparent after acute exposure, whereas the high ACR and chronic toxicity of some antihistamines probably related to interaction with a secondary rather than the primary pharmacological target. Acute or modeled chronic toxicity estimates have often been used for prioritizing pharmaceuticals. This may be seriously misleading because chronic effects are currently not predictable for APIs with specific receptor-mediated toxicity. However, it is exactly these APIs that are the most relevant in terms of environmental risks. Environ Toxicol Chem 2022;41:601-613. © 2021 SETAC.

Environmental risk assessments of multiclass pharmaceutical active compounds: selection of high priority concern pharmaceuticals using entropy-utility functions

This research aimed to identify high-risk pharmaceutically active compounds (PhACs) by analyzing occurrence (O), persistence (P), bioaccumulation (B), and toxicity (T) of 62 drugs which are widely used in Iran. A comprehensive approach was taken in risk assessment of the selected PhACs and in their prioritization using multiple-criteria decision analysis (MCDA) such as utility functions and principal component analysis (PCA). In practice, assigning weight to each criterion (i.e., O, P, B, and T) for risk assessment of PhACs is a challenge. In this research, the impact of giving both equal and unequal weight to each criterion by using a quantitative entropy method was studied. For risk assessment, two exposure approaches (consumption rate and occurrence of PhACs) and three MCDA approaches (PCA and utility functions with and without equal weights for each criterion) were compared. The utility function using equal weights for all O, P, B, and T criteria showed that thioridazine, pimozide, chlorpromazine, sertraline, clomipramine, and aripiprazole were at the highest level of risk, with concern score of 0.75, 0.75, 0.67, 0.58, 0.58, and 0.58, respectively. Unequal weight approach included additional compounds such as fluoxetine, citalopram, and methadone as a priority. All three MCDA approaches showed that sedatives and antidepressants were prevalent PhACs in the risk-based priority lists. However, the exposure-based approaches showed antibiotics and analgesics as the pharmaceutical of the highest priority. Overall, selection of the high priority concern pharmaceuticals depends on the prioritization approach employed. However, the utility function using unequal weights is a more conservative and effective approach for prioritization.

Ecotoxicity and photodegradation of Montelukast (a drug to treat asthma) in water

The present work focuses on the ecotoxicological effects of montelukast sodium (MTL) and its photoproducts, obtained under environmentally-like conditions. Despite of the potential presence in surface waters and the common use of MTL as asthma drug, limited data has been published for its photodegradation, while no information is available for its ecotoxicity. Light-induced degradation is an effective way for drugs to degrade in aquatic environments, and MTL is highly photosensitive, even by exposure to sunlight. In this study, solar-simulated irradiation of the drug in water was investigated. The drug was quickly converted into a series of photoproducts that were spectroscopically characterized. The possible photoreaction pathways were proposed. Ecotoxicity tests were performed on parent compound and mixture of photoproducts towards two bioindicators (Raphidocelis subcapitata and Daphnia magna). Results evidenced that effects of MTL on D. magna (EC50 = 16.4 mg/L) were greater than effects on R. subcapitata (EC50 = 195.7 mg/L). Microscopy observations revealed that MTL had mainly accumulated in the gut of daphnia. Toxicity data on photolysed solutions highlighted the presence of residual toxicity in all samples, evidencing that no complete mineralization occurred. Future research should focus on monitoring of MTL concentrations in the environment and study its effects in bioaccumulation tests.

Use of a large dataset to develop new models for estimating the sorption of active pharmaceutical ingredients in soils and sediments

Information on the sorption of active pharmaceutical ingredients (APIs) in soils and sediments is needed for assessing the environmental risks of these substances yet these data are unavailable for many APIs in use. Predictive models for estimating sorption could provide a solution. The performance of existing models is, however, often poor and most models do not account for the effects of soil/sediment properties which are known to significantly affect API sorption. Therefore, here, we use a high-quality dataset on the sorption behavior of 54 APIs in 13 soils and sediments to develop new models for estimating sorption coefficients for APIs in soils and sediments using three machine learning approaches (artificial neural network, random forest and support vector machine) and linear regression. A random forest-based model, with chemical and solid descriptors as the input, was the best performing model. Evaluation of this model using an independent sorption dataset from the literature showed that the model was able to predict sorption coefficients of 90% of the test set to within a factor of 10 of the experimental values. This new model could be invaluable in assessing the sorption behavior of molecules that have yet to be tested and in landscape-level risk assessments.

Impacts of Psychopharmaceuticals on the Neurodevelopment of Aquatic Wildlife: A Call for Increased Knowledge Exchange across Disciplines to Highlight Implications for Human Health

The global use of psychopharmaceuticals such as antidepressants has been steadily increasing. However, the environmental consequences of increased use are rarely considered by medical professionals. Worldwide monitoring efforts have shown that pharmaceuticals are amongst the multitude of anthropogenic pollutants found in our waterways, where excretion via urine and feces is thought to be the primary mode of pharmaceutical contamination. Despite the lack of clarity surrounding the effects of the unintentional exposure to these chemicals, most notably in babies and in developing fetuses, the US Environmental Protection Agency does not currently regulate any psychopharmaceuticals in drinking water. As the underlying reasons for the increased incidence of mental illness—particularly in young children and adolescents—are poorly understood, the potential effects of unintentional exposure warrant more attention. Thus, although links between environmental contamination and physiological and behavioral changes in wildlife species—most notably in fish—have been used by ecologists and wildlife biologists to drive conservation policy and management practices, we hypothesize that this knowledge may be underutilized by medical professionals. In order to test this hypothesis, we created a hierarchically-organized citation network built around a highly-cited “parent” article to explore connections between aquatic toxicology and medical fields related to neurodevelopment. As suspected, we observed that studies in medical fields such as developmental neuroscience, obstetrics and gynecology, pediatrics, and psychiatry cite very few to no papers in the aquatic sciences. Our results underscore the need for increased transdisciplinary communication and information exchange between the aquatic sciences and medical fields.

Erythromycin in the aquatic environment: deleterious effects on the initial development of zebrafish

Due to the large volume of erythromycin continuously reaching waterbodies and its high persistence, this antibiotic drug has been detected in the aquatic environment at elevated concentrations. Although the problem of the presence of erythromycin in the environment is evident due to its influence in development of antimicrobial resistance, the toxicological consequences on non-target organisms remain to be determined. There are no apparent data on the impact of environmentally relevant concentrations of erythromycin on developing fish. Data on toxic effects during development are essential for evaluation of environmental risk to organisms. Therefore, the aim of this study was to investigate the effects of exposure to erythromycin on certain parameters including hatchability, survival rate, heart rate, and behavior in developing zebrafish. Zebrafish were exposed to a range of environmentally relevant concentrations of antibiotic (0.001, 0.01, 0.1, 1 μg/L) and one concentration 10-fold higher (10 μg/L). Exposure to erythromycin at 0.1 μg/L delayed hatching and decreased survival rate. Exposure to all tested concentrations increased heart rate. Further, exposure to erythromycin at 1 or 10 μg/L enhanced swimming activity. Our results indicated that erythromycin present in the aquatic environment might lead to disabling consequences in developing fish organisms and subsequently may result in ecological imbalance in the natural environment.

Prioritizing pharmaceuticals based on environmental risks in the aquatic environment in China

In last two decades, the number of detected activated pharmaceutical ingredients (APIs) in the natural environment worldwide has increased due to their widespread use in daily life. However, given the large number of APIs that are currently in use (approximate 850 are on the market in China), it is impractical to investigate the occurrence, ecotoxicological effects, and perform environmental risk assessment for all drugs. Therefore, it is crucial to rank and prioritize APIs in the environment to identify the compounds of high concern. In China, since information on API usage is not available, an attempt was made to use the number of products per API (the number of pharmaceutical commodities that contain a particular API) on the market multiplied by its daily dose (average daily dose of medication for adults used for the primary therapeutic purpose) to replace the usage in the exposure modeling. Coupled with the hazard assessment, including acute and chronic toxicity of aquatic ecological effects and potential effects related to the therapeutic mode of action, risk scores were estimated and used for ranking. Application of the approach was illustrated for 259 APIs with product number no less than 4. A list of 20 APIs was finally identified as a potential priority, including drugs of cardiovascular, nervous system, respiratory system, musculoskeletal system and antibiotics. In the future, this approach could be applied to prioritize APIs in other countries/regions where information on API usage are limited or non-existent.

Environmental prioritization of pesticide in the Upper Citarum River Basin, Indonesia, using predicted and measured concentrations

A novel screening method was developed to prioritize aquatic and human health risks of pesticides based on usage data, runoff modelling and effect prediction. An important asset of this new method is that it does not require measured concentration data, which are often unavailable or difficult to obtain in low- and middle-income countries like Indonesia. The method was applied to prioritize 31 agricultural pesticides used in the Upper Citarum River Basin in West Java, Indonesia. Ranking of pesticides based on predicted concentrations generally showed good agreement with ranking based on concentrations measured by passive sampling. The individual pesticide intake through the consumption of river water was predicted to cause negligible human health risks, but substantial aquatic risks (i.e. PEC/PNEC >1) were predicted for profenofos (5.2.E+01), propineb (3.6.E+01), chlorpyrifos (2.6.E+01), carbofuran (1.7.E+01), imidacloprid (9.4.E+00), methomyl (7.6.E+00) and chlorantraniliprole (3.6.E+00). In order to protect the aquatic environment, water managers are advised to take measures to reduce the use and runoff of these pesticides in the UCRB. The screening assessment can be further refined by performing additional effect studies for some pesticides, pesticide mixtures and validation of the predicted water concentrations by targeted measurements.

Evaluation and development of models for estimating the sorption behaviour of pharmaceuticals in soils

Sorption is one of the key process that affects the fate and mobility of pharmaceuticals in the soil environment. Several models have been developed for estimating the sorption of organic chemicals, including ionisable compounds, in soil. However, the applicability of these models to pharmaceuticals has not been extensively tested. In this study, we generated a high-quality dataset on the sorption of twenty-one pharmaceuticals in different soil types and used these data to evaluate existing models and to develop new improved models. Sorption coefficients (Kd) of the pharmaceuticals ranged from 0.2 to 1249.2 L/kg. Existing models were unable to adequately estimate the measured sorption data. Using the data, new models were developed, incorporating molecular and soil descriptors, that outperformed the published models when evaluated against external data sets. While there is a need for further evaluation of these new models against broader sorption datasets obtained at environmentally relevant concentrations, in the future they could be highly useful in supporting environmental risk assessment and prioritization efforts for pharmaceutical ingredients.

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.

Pharmaceuticals and Environment: a web-based decision support for considering environmental aspects of medicines in use

Purpose

The database Pharmaceuticals and Environment is a non-commercial, freely available web-based decision support presenting compiled environmental information for pharmaceutical substances. It was developed by Region Stockholm and launched in 2016 at janusinfo.se. The purpose of this paper is to present the database, report on its current use, and reflect on lessons learned from developing and managing the database.

Methods

A standard operating procedure describes the work and content of the database, e.g., how information is retrieved, processed, and presented. Google Analytics was used for metrics. Issues related to the database have been discussed and handled by a reference group. The experiences from this work are presented.

Results

The database contains environmental hazard and risk information, primarily gathered from regulatory authorities and pharmaceutical companies. There are also assessments comparing substances within some groups of pharmaceuticals. The database is used by the Swedish Drug and Therapeutics Committees to include environmental aspects when recommending pharmaceuticals for health care providers. Page views show that users primarily look for information on commonly used substances, e.g., diclofenac and paracetamol/acetaminophen. Major problems for the development of the database are lack of data, lack of transparency, and discrepancies in the available environmental information.

Conclusion

In the absence of an adequate decision support produced by the regulatory authorities, we find the database Pharmaceuticals and Environment to be useful for Swedish Drug and Therapeutics Committees and health care providers, and it is our belief that the information can be valuable also in other settings.

Comparison of Small Molecule Biotransformation Half-Lives between Activated Sludge and Soil: Opportunities for Read-Across?

Compartment-specific degradation half-lives are essential pieces of information in the regulatory risk assessment of synthetic chemicals. However, their measurement according to regulatory testing guidelines is laborious and costly. Despite the obvious ecological and economic benefits of knowing environmental degradability as early as possible, its consideration in the early phases of rational chemical design is therefore challenging. Here, we explore the possibility to use half-lives determined in highly time- and work-efficient biotransformation experiments with activated sludge and mixtures of chemicals to predict soil half-lives from regulatory simulation studies. We experimentally determined half-lives for 52 structurally diverse agrochemical active ingredients in batch reactors with three concentrations of the same activated sludge. We then developed bi- and multivariate models for predicting half-lives in soil by regressing the experimentally determined half-lives in activated sludge against average soil half-lives of the same chemicals extracted from regulatory data. The models differed in how we accounted for sorption-related bioavailability differences in soil and activated sludge. The best-performing models exhibited good coefficients of determination (R² of around 0.8) and low average errors (<factor of 3 in half-life predictions) and were robust in cross-validation. From a practical perspective, these results suggest that it may indeed be possible to read across from half-lives determined in highly efficient biotransformation experiments in activated sludge to soil half-lives, which are obtained from much more work- and resource-intense regulatory studies, and that these predictions are clearly superior to predictions based on the output of BIOWIN, a publicly available quantitative structure-biodegradation relationship (QSBR) model. From a theoretical perspective, these results suggest that soil and activated sludge microbial communities, although certainly different in terms of taxonomic composition, may be functionally similar with respect to the enzymatic transformation of environmentally relevant concentrations of a diverse range of chemical compounds.

Ecological risk assessment of fifty pharmaceuticals and personal care products (PPCPs) in Chinese surface waters: A proposed multiple-level system

Interest in the risks posed by trace concentrations of pharmaceuticals and personal care products (PPCPs) in surface waters is increasing, particularly with regard to potential effects of long-term, low-dose exposures of aquatic organisms. In most cases, the actual studies on PPCPs were risk assessments at screening-level, and accurate estimates were scarce. In this study, exposure and ecotoxicity data of 50 PPCPs were collected based on our previous studies, and a multiple-level environmental risk assessment was performed. The 50 selected PPCPs are likely to be frequently detected in surface waters of China, with concentrations ranging from the ng L^-1 to the low-g L^-1, and the risk quotients based on median concentrations ranged from 2046 for nonylphenol to 0 for phantolide. A semi-probabilistic approach screened 33 PPCPs that posed potential risks to aquatic organisms, among which 15 chemicals (nonylphenol, sulfamethoxazole, di (2-ethylhexyl) phthalate, 17β-ethynyl estradiol, caffeine, tetracycline, 17β-estradiol, estrone, dibutyl phthalate, ibuprofen, carbamazepine, tonalide, galaxolide, triclosan, and bisphenol A) were categorized as priority compounds according to an optimized risk assessment, and then the refined probabilistic risk assessment indicated 12 of them posed low to high risk to aquatic ecosystem, with the maximum risk products ranged from 1.54% to 17.38%. Based on these results, we propose that the optimized risk assessment was appropriate for screening priority contaminants at national scale, and when a more accurate estimation is required, the refined probability risk assessment is useful. The methodology and process might provide reference for other research of chemical evaluation and management for rivers, lakes, and sea waters.

Embryo bioassays with aquatic animals for toxicity testing and hazard assessment of emerging pollutants: A review

This review article gathers the available information on the use of embryo-tests as high-throughput tools for toxicity screening, hazard assessment and prioritization of new and existing chemical compounds. The approach is contextualized considering the new legal trends for animal experimentation, fostering the 3R policy, with reduction of experimental animals, addressing the potential of embryo-tests as high-throughput toxicity screening and prioritizing tools. Further, the current test guidelines, such as the ones provided by OECD and EPA, focus mainly in a limited number of animal lineages, particularly vertebrates and arthropods. To extrapolate hazard assessment to the ecosystem scale, a larger diversity of taxa should be tested. The use of new experimental animal models in toxicity testing, from a representative set of taxa, was thoroughly revised and discussed in this review. Here, we critically review current tools and the main advantages and drawbacks of different animal models and set researcher priorities.

Uptake and Effects of the Beta-Adrenergic Agonist Salbutamol in Fish: Supporting Evidence for the Fish Plasma Model

The fish plasma model (FPM) predicts the fish blood plasma concentration of a pharmaceutical from the water concentration to which the fish is exposed and compares it with the human therapeutic plasma concentration (H_ther PC) with the postulate that no adverse toxic effects occur below the H_ther PC. The present study provides several lines of evidence supporting the FPM for the beta-adrenergic agonist salbutamol, a small cationic molecule at ambient pH. Salbutamol exhibited very low acute toxicity to early and adult life stages of fish. Biomass reduction in fish early life stages was the most sensitive apical endpoint, with no-observed-effect concentrations (NOECs) in the low mg/L range after continuous exposure for up to 120 d. Given that predicted and measured environmental concentrations are at least 1000-fold lower, the risk of salbutamol in freshwater is deemed very low. Increase in heart beat rate and decrease in total triglyceride content in fish also occurred at the low mg/L range and resembled effects known from humans. This finding supports the FPM assumption of conserved targets in fish with similar functionality. Plasma concentrations measured in adult and juvenile fish exposed to water concentrations at approximately the NOECs exceeded H_ther PC and even approached plasma concentrations toxic to humans. This result confirms for salbutamol the FPM hypothesis that no adverse (i.e., population-relevant) toxic effects occur in fish below the H_ther PC. Environ Toxicol Chem 2019;38:2509-2519. © 2019 SETAC.

Global scanning of selective serotonin reuptake inhibitors: occurrence, wastewater treatment and hazards in aquatic systems

As the global population becomes more concentrated in urban areas, resource consumption, including access to pharmaceuticals, is increasing and chemical use is also increasingly concentrated. Unfortunately, implementation of waste management systems and wastewater treatment infrastructure is not yet meeting these global megatrends. Herein, pharmaceuticals are indicators of an urbanizing water cycle; antidepressants are among the most commonly studied classes of these contaminants of emerging concern. In the present study, we performed a unique global hazard assessment of selective serotonin reuptake inhibitors (SSRIs) in water matrices across geographic regions and for common wastewater treatment technologies. SSRIs in the environment have primarily been reported from Europe (50%) followed by North America (38%) and Asia-Pacific (10%). Minimal to no monitoring data exists for many developing regions of the world, including Africa and South America. From probabilistic environmental exposure distributions, 5th and 95th percentiles for all SSRIs across all geographic regions were 2.31 and 3022.1 ng/L for influent, 5.3 and 841.6 ng/L for effluent, 0.8 and 127.7 ng/L for freshwater, and 0.5 and 22.3 ng/L for coastal and marine systems, respectively. To estimate the potential hazards of SSRIs in the aquatic environment, percent exceedances of therapeutic hazard values of specific SSRIs, without recommended safety factors, were identified within and among geographic regions. For influent sewage and wastewater effluents, sertraline exceedances were observed 49% and 29% of the time, respectively, demonstrating the need to better understand emerging water quality hazards of SSRIs in urban freshwater and coastal ecosystems. This unique global review and analysis identified regions where more monitoring is necessary, and compounds requiring toxicological attention, particularly with increasing aquatic reports of behavioral perturbations elicited by SSRIs.

Comparison of Prioritisation Schemes for Human Pharmaceuticals in the Aquatic Environment

Only a small proportion of pharmaceuticals available for commercial use have been monitored in the aquatic environment, and even less is known about the effects on organisms. With thousands of pharmaceuticals in use, it is not feasible to monitor or assess the effects of all of these compounds. Prioritisation schemes allow the ranking of pharmaceuticals based on their potential as environmental contaminants, allowing resources to be appropriately used on those which are most likely to enter the environment and cause greatest harm. Many different types of prioritisation schemes exist in the literature and those utilising predicted environmental concentrations (PECs), the fish plasma model (FPM), critical environmental concentrations (CECs) and acute ecotoxicological data were assessed in the current study using the 50 most prescribed drugs in the UK. PECs were found to be overestimates of mean measured environmental concentrations but mainly underestimations of maximum concentrations. Acute ecological data identified different compounds of concern to the other effects assessments although the FPM and CECs methods were more conservative. These schemes highlighted antidepressants, lipid regulators, antibiotics, antihypertensive compounds and ibuprofen as priority compounds for further study and regulation.

Toward sustainable environmental quality: Priority research questions for Europe

The United Nations' Sustainable Development Goals have been established to end poverty, protect the planet, and ensure prosperity for all. Delivery of the Sustainable Development Goals will require a healthy and productive environment. An understanding of the impacts of chemicals which can negatively impact environmental health is therefore essential to the delivery of the Sustainable Development Goals. However, current research on and regulation of chemicals in the environment tend to take a simplistic view and do not account for the complexity of the real world, which inhibits the way we manage chemicals. There is therefore an urgent need for a step change in the way we study and communicate the impacts and control of chemicals in the natural environment. To do this requires the major research questions to be identified so that resources are focused on questions that really matter. We present the findings of a horizon-scanning exercise to identify research priorities of the European environmental science community around chemicals in the environment. Using the key questions approach, we identified 22 questions of priority. These questions covered overarching questions about which chemicals we should be most concerned about and where, impacts of global megatrends, protection goals, and sustainability of chemicals; the development and parameterization of assessment and management frameworks; and mechanisms to maximize the impact of the research. The research questions identified provide a first-step in the path forward for the research, regulatory, and business communities to better assess and manage chemicals in the natural environment. Environ Toxicol Chem 2018;37:2281-2295. © 2018 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.