The significance of different health institutions and their respective contributions of active pharmaceutical ingredients to wastewater

Occurrence and source identification of antibiotics and antibiotic resistance genes in groundwater surrounding urban hospitals

Urban groundwater, serving as a critical reservoir for potable water, faces susceptibility to contamination from discrete sources such as hospital wastewater. This study investigates the distribution and plausible origins of antibiotics and antibiotic resistance genes (ARGs) in urban groundwater, drawing comparisons between areas proximal to hospitals and non-hospital areas. Ofloxacin and oxytetracycline emerged as the prevalent antibiotics across all samples, with a discernibly richer array of antibiotic types observed in groundwater sourced from hospital-adjacent regions. Employing a suite of multi-indicator tracers encompassing indicator drugs, Enterococci, ammonia, and Cl/Br mass ratio, discernible pollution from hospital or domestic sewage leakage was identified in specific wells, correlating with an escalating trajectory in antibiotic contamination. Redundancy analysis underscored temperature and dissolved organic carbon as principal environmental factors influencing antibiotics distribution in groundwater. Network analysis elucidated the facilitating role of mobile genetic elements, such as int1 and tnpA-02 in propagating ARGs. Furthermore, ARGs abundance exhibited positive correlations with temperature, pH and metallic constituents (e.g., Cu, Pb, Mn and Fe) (p < 0.05). Notably, no conspicuous correlation manifested between antibiotics and ARGs. These findings accentuate the imperative of recognizing the peril posed by antibiotic contamination in groundwater proximal to hospitals and advocate for the formulation of robust prevention and control strategies to mitigate the dissemination of antibiotics and ARGs.

Catchment area, fate, and environmental risks investigation of micropollutants in Danish wastewater

This study aimed to investigate the spatial distribution of micropollutants in wastewater related to catchment area, and their environmental risks and fate. About 24-h flow proportional effluent (n = 26) wastewater samples were collected from eight WWTPs across Denmark. From five of these WWTPs corresponding influent samples (n = 20) were collected. Samples were enriched by multi-layer solid phase and analysed by liquid chromatography-high-resolution mass spectrometry and comprehensive two-dimensional gas chromatography with high-resolution mass spectrometry detection. We detected and quantified 79 micropollutants from a list of 291 micropollutants in at least one influent or effluent wastewater sample. From this we found that 54 micropollutants decreased in concentrations during wastewater treatment, while O-desmethylvenlafaxine, carbamazepine, amitriptyline, benzothiazole, terbutryn, and citalopram increased in concentrations through the WWTP.The toxicity of effluent wastewater samples was assessed by EC50 using Raphidocelis subcapitata (R. subcapitata) and LC50 using the crustacean Daphnia magna (D. Magna), for which six micropollutants were detected above the predicted no-effect concentration. Our study demonstrates that catchment area influences the micropollutant composition of wastewater. Out of 19 pharmaceuticals, the measured concentration in influent wastewater was predicted within a factor of 10 from sale numbers and human excretion, which demonstrates the strong influence of catchment area on micropollutant composition.

European-wide spatial analysis of sewage treatment plants and the possible benefits to nature of advanced treatment to reduce pharmaceutical emissions

Pharmaceuticals are known to widely occur in the environment and to affect the health of ecosystems. Sewage treatment plants (STPs) are main emission pathways for pharmaceuticals, which are often not sufficiently removed during wastewater treatment. In Europe, STP treatment requirements are specified under the Urban WasteWater Treatment Directive (UWWTD). The introduction of advanced treatment techniques, such as ozonation and activated carbon, under the UWWTD is expected to be an important option to reduce pharmaceutical emissions. In this study, we present a European-wide analysis of STPs reported under the UWWTD, their current treatment level and potential to remove a set of 58 prioritised pharmaceuticals. Three different scenarios were analysed to show 1) UWWTD present effectiveness, 2) the effectiveness at full UWWTD compliance, and 3) the effectiveness when advanced treatment is implemented at STPs with a treatment capacity of >100.000 person equivalents. Based on a literature study, the potential of individual STPs to reduce pharmaceutical emissions ranged from an average of 9% for STPs with primary treatment to 84% for STPs applying advanced treatment. Results of our calculations show that European-wide emission of pharmaceuticals can be reduced with 68% when large STPs are updated with advanced treatment, but spatial differences exist. We argue that adequate attention should also be paid with regards to preventing environmental impacts of STPs with a capacity <100.000 p.e. Circa 44% of total STP effluent is emitted near Natura2000 sites (EU nature protection areas). Of all surface waters receiving STP effluent for which the ecological status has been assessed under the Water Framework Directive, 77% have a status of less than good. Relatively often only primary treatment is applied to wastewater emitted into coastal waters. This analysis can be used to further model pharmaceutical concentrations in European surface waters, to identify STPs for which more advanced treatment might be required and to protect EU aquatic biodiversity.

Review of hospital effluents: special emphasis on characterization, impact, and treatment of pollutants and antibiotic resistance

Health care institutions generate large volumes of liquid effluents from specific activities related to healthcare, analysis, and research. Their direct discharge into the environment has various negative effects on aquatic environments and human health, due to their high organic matter charges and the presence of various emerging contaminants such as disinfectants, drugs, bacteria, viruses, and parasites. Moreover, hospital effluents, by carrying antibiotics, contribute to the development of antibiotic-resistant microorganisms in the environment. This resistance has become a global issue that manifests itself variously in different countries, causing the transmission of different infections. In this respect, an effort is provided to protect water resources by current treatment methods that imply physical-chemical processes such as adsorption and advanced oxidation processes, biological processes such as activated sludge and membrane bioreactors and other hybrid techniques. The purpose of this review is to improve the knowledge on the composition and impact of hospital wastewater on man and the environment, highlighting the different treatment techniques appropriate to this type of disposal before discharge into the environment.

Occurrence of pharmaceuticals in the wastewater of a Greek hospital: Combining consumption data collection and LC-QTOF-MS analysis

In this article we applied drug consumption approach and chemical analysis in parallel to investigate the concentrations of a large number of pharmaceuticals in different streams of a General Hospital. Drugs consumption data was collected during two periods (Period 1, 2) and the predicted environmental concentrations (PECs) were estimated for the wastewater of a building housing specific medical services (Point A) and for the entire hospital (Point B). Hospital wastewater samples (HWW) samples were also collected from these points and periods and the measured environmental concentrations (MEC) were determined using UHPLC-ESI-QTOF-MS/MS. According to consumption data, the highest number of drugs was consumed in the departments of Hematology, Intensive Care Unit, Cardiology, Internal Medicine, and Oncology, while the number of active substances used in the hospital was 413 (Period 1) and 362 (Period 2). For most substances, much higher PEC and MEC values were found at the HWW of Point A indicating that on-site treatment of this stream could be examined in the future. The application of wide-scope target analysis allowed the quantification of 122 compounds, while 21 additional substances were identified using suspect screening. The highest mean concentrations in Period 1 were found for acetaminophen (1100 μg/L) and rifaximin (723 μg/L), while in Period 2 for iopromide (458 μg/L) and acyclovir (408 μg/L). Among the detected compounds, 19 metabolites were determined. Atenolol acid, 1-hydroxy-midazolam and clopidogrel carboxylic acid were quantified at concentrations much higher than parent compounds indicating the importance of metabolites' monitoring in HWW. Calculation of PEC/MEC ratio for 36 pharmaceuticals showed sufficient correlation of these values for 19 % to 33 % of the substances depending on the examined period and sampling point. The parallel collection of drugs consumption data and chemical analysis give a thorough picture of the substances present in HWW and their main sources, facilitating decision-making for their better management.

[Pharmaceutical residues in aquatic compartments : Status quo and perspectives]

Meanwhile, more than 600 different pharmaceuticals have been detected in surface water, with diclofenac, ethinylestradiol and cotrimoxazole as the frequently dominating substances. The highest concentrations of parent compounds, metabolites and transformation products were measured particularly in urban wastewater discharges, in liquid manure from animal husbandries and aquaculture facilities; however, the levels of certain psychopharmaceuticals and estrogen effective substances in surface water have been associated with behavioral changes and reproduction toxicity in fish species. As a consequence, in the near future measures must be implemented that noticeably reduce the discharge of pharmaceuticals into the environment. With respect to drinking water, the currently detected concentrations of active agents have so far not been found to reach toxicologically relevant concentrations for human beings. In contrast, swimming and bathing in receiving waters can be critical.

Structural Adaptive, Self-Separating Material for Removing Ibuprofen from Waters and Sewage

β-Cyclodextrin nanosponge (β-CD-M) was used for the adsorption of ibuprofen (IBU) from water and sewage. The obtained material was characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET), Barrett-Joyner-Halenda (BJH), Harkins and Jura t-Plot, zeta potential, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and elementary analysis (EA). Batch adsorption experiments were employed to investigate the effects of the adsorbent dose, initial IBU concentration, contact time, electrolyte ions and humic acids, and sewage over adsorption efficiency. The experimental isotherms were show off using Langmuir, Freundlich, Hill, Halsey and Sips isotherm models and thermodynamic analysis. The fits of the results were estimated according to the Sips isotherm, with a maximum adsorption capacity of 86.21 mg g-1. The experimental kinetics were studied by pseudo-first-order, pseudo-second-order, Elovich, modified Freundlich, Weber Morris, Bangham's pore diffusion, and liquid film diffusion models. The performed experiments revealed that the adsorption process fits perfectly to the pseudo-second-order model. The Elovich and Freundlich models indicate chemisorption, and the kinetic adsorption model itself is complex. The data obtained throughout the study prove that this nanosponge (NS) is extremely stable, self-separating, and adjusting to the guest structure. It also represents a potential biodegradable adsorbent for the removal IBU from wastewaters.

Occurrence and ecological risk assessment of pharmaceuticals and cocaine in the urban drainage channels of Santos beaches (São Paulo, Brazil): a neglected, but sensitive issue

In some Brazilian coastal cities, it is common to observe 'black tongues' in beaches, i.e. a mixture of urban runoff and untreated domestic sewage containing pollutants of emerging concern, namely pharmaceutical and personal care products (PPCPs), flowing into the South Atlantic Ocean. Such diffuse loads of pollutants might expose nontarget aquatic organisms to harmful compounds. In this work, the occurrence and preliminary ecological risk of 27 PPCPs of various therapeutic classes (including cocaine and its primary metabolite, benzoylecgonine) were investigated, for the first time, in seven urban drainage channels whose diffuse loads flow continuously to the beaches of Santos Bay, São Paulo, Brazil. Of these, 21 compounds were detected using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), and nine of them were consistently quantified in all urban channels of Santos, suggesting that those pollutants are ubiquitous in this region: caffeine (143.4-516.0 ng/L), losartan (4.2-21.8 ng/L), atenolol (1.1-18.2 ng/L), acetaminophen (1.5-13.8 ng/L), benzoylecgonine (1.0-4.8 ng/L), carbamazepine (1.1-4.0 ng/L), diclofenac (1.9-3.5 ng/L), cocaine (0.5-1.7 ng/L), and orphenadrine (0.1-0.8 ng/L). Moreover, twelve compounds were found below the limit of quantification ( <LOQ): citalopram, propranolol, diazepam, rosuvastatin, atorvastatin, midazolam, ranitidine, chlortalidone, clopidogrel, chlorpheniramine, enalapril and valsartan. According to our knowledge, this is the first report on the occurrence of midazolam, ranitidine and chlorpheniramine in surface waters in Latin America and, therefore, these compounds should be considered environmental warning signs. A preliminary ecological risk assessment revealed that caffeine, acetaminophen and losartan presented a moderate risk, and carbamazepine a low risk to sensitive aquatic organisms at maximum measured concentrations. This study provides valuable information to reinforce the importance of a continuous monitoring of the diffuse loads (containing PPCPs and illicit drugs) flowing to the coastal zones in developing countries.

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

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

Removal of pharmaceuticals from wastewater of health care facilities

Health care facilities can represent point sources for pharmaceutical residues in public sewer systems. Compared to general hospitals, more specialized health care facilities might also have a different pattern of medication. Therefore, the on-site treatment of wastewater from such facilities could be an effective strategy to reduce emissions into water bodies and was the aim of this study. Wastewater from three health care facilities (nursing home, clinic with orthopaedic focus, and psychiatric clinic) was treated in lab-scale and semi-industrial trials. Biological treatment was performed via an ultrafiltration membrane bioreactor (UF-MBR), after which adsorption onto granular activated carbon (using rapid-small-scale column tests GAC-RSSCT), ozonation and a UV/H₂O₂ advanced oxidation process (AOP) were tested and compared. The removal of 17 pharmaceutical compounds and drug metabolites from 9 drug classes (e.g. analgesics, antibiotics, anticonvulsants) was evaluated. Most of the measured OMP were detected with concentrations between 1,000 and 30,000 ng L^-1 in the influent of the MBR. The UF-MBR provided an effective mechanical-biological cleaning of the wastewater, with micropollutant removal efficiencies between 0 and > 95%, making further treatment necessary to remove the micropollutants. Each combination of the UF-MBR with one of the three further treatments achieved removal efficiencies above 80% for most of the investigated substances, reducing many to below the quantification limit of 10 ng L^-1. The results show the general suitability of combining the UF-MBR with either GAC-adsorption, ozonation or AOP for eliminating pharmaceutical residues. However, the AOP process has a significantly higher energy demand than the other two processes. Moreover, specific settings and dosages depend on the respective wastewater matrix.

Natural fluorescence emission - an indirect measurement of applied ozone dosages to remove pharmaceuticals in biologically treated wastewater

This study investigated the feasibility of UV-absorbance and fluorescence as monitoring tools for ozone dosages applied to effluents from wastewater treatment plans (WWTPs). Secondary treated effluents from five Swedish WWTPs underwent ozonation (at dosages ranging 0.5-12.0 mg O₃/L) in bench-scale experiments. Correlations between ozone dosages and UV-absorbance at 254 and 272 nm were extrapolated with the first one being preferential for the wastewaters used because of its higher signal. UV-absorbance could detect differences in the applied ozone dosage as low as 1 mg/L, making it suitable to monitor effluent ozone treatment processes. Next, fluorescence was investigated at wavelength transitions that have being associated with humic-like fluorescents (Ex249Em450 and Ex335Em450) and protein-like fluorescents (Ex275Em340 and Ex231Em360 and Ex231Em315 and Ex275Em310). The Ex249Em450 transition was found to have the highest signal in all effluents and the best linear regression fitting with the ozone dosages over a wide range. However, low ozone dosages (0.5-3.0 mg O₃/L), Ex335Em450 wavelength transition showed a more constant slope among the different domestic wastewater samples with slightly better R ² values than the Ex249Em450 transition. Fluorescence removal via ozonation correlated with the pharmaceutical removal; however, the wellness of fitting was directly dependent on the pharmaceuticals' reactivity with ozone. Pharmaceuticals with moderate reactivity towards ozone appeared to be linearly correlated with the Ex249Em450 transition, while very reactive or recalcitrant pharmaceuticals had an exponential or a parabolic dependency. This means that fluorescence can potentially be used as a qualitative tool for pharmaceutical removal. Abbreviations: APIs, Active Pharmaceutical Ingredients; DOM, Dissolved organic matter; WWTPs, wastewater treatment plans; NOM, Natural organic matter; UV, Ultra-Violet light; DOC, Dissolved organic carbon.

Assessing hospital impact on pharmaceutical levels in a rural 'source-to-sink' water system

It is widely recognised that inadequate removal of pharmaceuticals in wastewater may lead to their presence in surface waters. Hospitals are key point-sources for pharmaceuticals entering municipal waterways, and rural hospitals are of concern as receiving wastewater treatment plants (WWTPs) may be smaller, less advanced and thus less efficient. While most research has focused on urban settings, here we present results from a rural ''source-to-sink'' study around a hospital. The aim was to determine the contribution of pharmaceuticals discharged to a municipal wastewater system, and, to assess pharmaceutical removal efficiency in the WWTP. Samples were collected daily for one month to assess water quality and pharmaceuticals in the broader water cycle: (i) raw water supply; (ii) treated hospital tap water; (iii) hospital wastewater discharge; (iv) combined WWTP influent; and (v) final WWTP effluent. Target compounds included analgesics/antiinflammatories, antibiotics, psychiatric drugs, and a synthetic estrogen hormone. Concentrations ranged from: 3 ng/L (carbamazepine) to 105,910 ng/L (paracetamol) in hospital discharge; 5 ng/L (ibuprofen) to 105,780 ng/L (paracetamol) in WWTP influent; and 60 ng/L (clarithromycin) to 36,201 ng/L (paracetamol) in WWTP effluent. WWTP removal ranged from 87% (paracetamol) to <0% (carbamazepine and clarithromycin), and significant correlations with water quality characteristics and WWTP flow data were observed for some compounds. Results suggested that the hospital is an important source of certain pharmaceuticals entering municipal wastewater, and associated water quality parameters are impacted. Pharmaceutical persistence in the WWTP effluent highlighted the direct pathway these compounds have into receiving surface water, where their impact remains uncharacterised. Rural regions may face future challenges mitigating environmental risk as WWTP infrastructure ages, populations grow and pharmaceutical use and diversity continue to increase.

Selected Pharmaceuticals in Different Aquatic Compartments: Part I-Source, Fate and Occurrence

Potential risks associated with releases of human pharmaceuticals into the environment have become an increasingly important issue in environmental health. This concern has been driven by the widespread detection of pharmaceuticals in all aquatic compartments. Therefore, 22 pharmaceuticals, 6 metabolites and transformation products, belonging to 7 therapeutic groups, were selected to perform a systematic review on their source, fate and occurrence in different aquatic compartments, important issues to tackle the Water Framework Directive (WFD). The results obtained evidence that concentrations of pharmaceuticals are present, in decreasing order, in wastewater influents (WWIs), wastewater effluents (WWEs) and surface waters, with values up to 14 mg L⁻¹ for ibuprofen in WWIs. The therapeutic groups which presented higher detection frequencies and concentrations were anti-inflammatories, antiepileptics, antibiotics and lipid regulators. These results present a broad and specialized background, enabling a complete overview on the occurrence of pharmaceuticals in the aquatic compartments.

Risk-management tool for environmental prioritization of pharmaceuticals based on emissions from hospitals

Over the past decade, the health care sector has become increasingly aware of the impact of pharmaceutical emissions to the environment. Yet, it remains unclear which compounds are the most relevant to address and at what point emission control is most effective. This study presents a modelling framework to prioritize pharmaceuticals based on their relative risks for aquatic organisms, using purchase and prescription data from hospitals. The framework consists of an emission prediction module and a risk prioritization module. The emission prediction module accounts for three different routes of intake (oral, intravenous, rectal), for non-patient consumption, and for delayed athome excretion due to relatively long half-lives or prescription durations of selected pharmaceuticals. We showcase the modelling framework with 16 pharmaceuticals administered at two Dutch academic hospitals. Predictions were validated with experimental data from passive sampling in the sewer system. With the exception of metformin, all predictions were within a factor of 10 from measurements. The risk prioritization module ranks each pharmaceutical based on its predicted relative risk for aquatic organisms. The resulting prioritization suggests that emission mitigation strategies should mainly focus on antibiotics and non-steroidal anti-inflammatory drugs (NSAIDs).

Hospital wastewaters treatment: Fenton reaction vs. BDDE vs. ferrate(VI)

Various types of micropollutants, e.g., pharmaceuticals and their metabolites and resistant strains of pathogenic microorganisms, are usually found in hospital wastewaters. The aim of this paper was to study the presence of 74 frequently used pharmaceuticals, legal and illegal drugs, and antibiotic-resistant bacteria in 5 hospital wastewaters in Slovakia and Czechia and to compare the efficiency of several advanced oxidations processes (AOPs) for sanitation and treatment of such highly polluted wastewaters. The occurrence of micropollutants and antibiotic-resistant bacteria was investigated by in-line SPE-LC-MS/MS technique and cultivation on antibiotic and antibiotic-free selective diagnostic media, respectively. The highest maximum concentrations were found for cotinine (6700 ng/L), bisoprolol (5200 ng/L), metoprolol (2600 ng/L), tramadol (2400 ng/L), sulfamethoxazole (1500 ng/L), and ranitidine (1400 ng/L). In the second part of the study, different advanced oxidation processes, modified Fenton reaction, ferrate(VI), and oxidation by boron-doped diamond electrode were tested in order to eliminate the abovementioned pollutants. Obtained results indicate that the modified Fenton reaction and application of boron-doped diamond electrode were able to eliminate almost the whole spectrum of selected micropollutants with efficiency higher than 90%. All studied methods achieved complete removal of the antibiotic-resistant bacteria present in hospital wastewaters.

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

BACKGROUND

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

RESULTS

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

CONCLUSIONS

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

Reducing aquatic micropollutants - Increasing the focus on input prevention and integrated emission management

Pharmaceuticals and many other chemicals are an important basis for nearly all sectors including for example, food and agriculture, medicine, plastics, electronics, transport, communication, and many other products used nowadays. This comes along with a tremendous chemicalization of the globe, including ubiquitous presence of products of chemical and pharmaceutical industries in the aquatic environment. Use of these products will increase with population growth and living standard as will the need for clean water. In addition, climate change will exacerbate availability of water in sufficient quantity and quality. Since its implementation, conventional wastewater treatment has increasingly contributed to environmental protection and health of humans. However, with the increasing pollution of water by chemicals, conventional treatment turned out to be insufficient. It was also found that advanced effluent treatment methods such as extended filtration, the sorption to activated charcoal or advanced oxidation methods have their own limitations. These are, for example, increased demand for energy and hazardous chemicals, incomplete or even no removal of pollutants, the generation of unwanted products from parent compounds (transformation products, TPs) of often-unknown chemical structure, fate and toxicity. In many countries, effluent treatment is available only rarely if at all let alone advanced treatment. The past should teach us, that focusing only on technological approaches is not constructive for a sustainable water quality control. Therefore, in addition to conventional and advanced treatment optimization more emphasis on input prevention is urgently needed, including more and better control of what is present in the source water. Measures for input prevention are known for long. The main focus though has always been on the treatment, and measures taken at the source have gained only little attention so far. A more effective and efficient approach, however, would be to avoid pollution at the source, which would in turn allow more targeted treatment to meet treated water quality objectives globally. New developments within green and sustainable chemistry are offering new approaches that allow for input prevention and a more targeted treatment to succeed in pollution elimination in and at the source. To put this into practice, engineers, water scientists and chemists as well as microbiologists and scientists of other related disciplines need to cooperate more extensively than in the past. Applying principles such as the precautionary principle, or keeping water flows separate where possible will add to this. This implies not minimizing the efforts to improve wastewater treatment but to design effluents and chemicals in such a way that treatment systems and water environments can cope successfully with the challenge of micropollutants globally (Kümmerer et al., 2018). This paper therefore presents in its first part some of the limitations of effluent treatment in order to demonstrate the urgent need for minimizing water pollution at the source and, information on why source management is urgently needed to improve water quality and stimulate discussions how to protect water resources on a global level. Some principles of green and sustainable chemistry as well as other approaches, which are part of source management, are presented in the second part in order to stimulate discussion.

Studying the fate of the drug Chlorprothixene and its photo transformation products in the aquatic environment: Identification, assessment and priority setting by application of a combination of experiments and various in silico assessments

Chlorprothixene (CPTX) is an antipsychotic drug of the thioxanthene class. Although it is widely used as a tranquillizer in psychiatry, anesthesiology, pediatrics, and in general medical practice, there is a gap in knowledge regarding its occurrence and fate in the environment. Therefore, we provide for the first-time data on the environmental fate and ecotoxicity of CPTX and its potential photo-transformations products (PTPs). Firstly, two standardized biodegradation tests (Closed Bottle test (CBT) and Manometric Respiratory test (MRT)) were performed to assess CPTX's environmental biodegradability. Then, its photodegradability was studied using Xenon and UV lamps. Effects of different conditions (initial drug concentration, pH, and temperature) were applied during UV-photodegradation. Subsequently, the time courses of CPTX and dissolved organic carbon (DOC) concentrations were monitored throughout the photodegradation tests. After that, high-resolution mass spectrometry was employed to elucidate the structures of the formed photo-transformation products (PTPs). In addition, biodegradation tests were performed for the photolytic mixtures to assess the biodegradability of the PTPs. Finally, the (eco)toxicity assessment for CPTX and its photolytic mixtures was predicted using different (quantitative) structure-activity relationship ((Q)SAR) software. CPTX was found to be not readily biodegradable in CBT and MRT. CPTX was not eliminated by irradiation with the Xenon lamp, however primarily eliminated using the UV-lamp. The CPTX elimination during UV-irradiation was faster at lower concentrations. CPTX UV-photodegradation was affected by pH value, while not affected by the temperature of the irradiated solution. 13 PTPs were detected in UV-photolysis mixtures. One additional product was detected in CPTX standard solution, and it was degraded simultaneously with CPTX during UV-irradiation. On one hand, Biodegradation assays revealed that UV-photolytic mixtures of CPTX, containing its PTPs, were not better biodegradable than CPTX itself. On the other hand, LC-MS analysis showed some PTPs which were eliminated after the biodegradation tests indicating possible biodegradability of these PTPs. This because those PTPs are present in low concentrations in the photolysis mixture and their effect can be hindered by the effect of CPTX and other non-biodegradable PTPs. QSAR analysis revealed that CPTX and some of its PTPs may have some human and/or eco-toxic properties. In conclusion, the release of CPTX into aquatic environments could be harmful. Therefore, further research focusing on CPTX and its PTPs are strongly recommended.

Ozonation of nursing home wastewater pretreated in a membrane bioreactor

Nursing home (NH) wastewater was pretreated in an ultrafiltration membrane bioreactor (MBR) and subsequently ozonated in a pilot plant in order to evaluate the elimination of pharmaceutically active compounds (PhACs). Dosing of the pre-treated wastewater with 5 mg ozone (O₃) L^-1 led to the elimination of >50% for nearly all investigated PhACs in the ozonation plant, whereas dosing 10 mg O₃ L^-1 increased elimination to >80%. A total hydraulic retention time of 12.8 min proved sufficient for PhAC elimination. Specific ozone consumption and influent dissolved organic carbon (DOC) (8.2-9.5 mg L^-1) were in similar ranges for all three performed trials. Combining the MBR with subsequent ozonation at a dosage of 5 mg O₃ L^-1 achieved elimination of >90% and effluent concentrations below 250 ng L^-1 for nearly all the investigated PhACs. Influent concentrations of the MBR were comparable to those found in municipal wastewater. Thus, the recommended dosage for PhAC elimination of 5 mg O₃ L^-1 (i.e. a specific consumption of 0.6 g O₃*(g DOC)^-1) is in the same range as for municipal wastewater. However, due to a smaller plant size, the specific costs for treating NH wastewater would significantly exceed those of treating municipal wastewater.

Not only biocidal products: Washing and cleaning agents and personal care products can act as further sources of biocidal active substances in wastewater

The emission sources of biocidal active substances in households have been under discussion since these substances have been detected frequently in municipal wastewater and receiving surface water bodies. Therefore, the goal of this study was to investigate the products responsible for the emission of these substances to wastewater. We analysed the wastewater of two streets for a set of biocidal active substances. Time-proportional sampling was conducted for one week of each season during one year in each street. The 14 substances analysed with liquid chromatography coupled with tandem mass spectrometry were 1,2-benzisothiazol-3(2H)-one (BIT), C₁₂-benzalkonium chloride, carbendazim, 5-chloro-2-methyl-2H-isothiazol-3-one (CMIT), dichlorooctylisothiazolinone (DCOIT), N,N-diethyl-meta-toluamide (DEET), diuron, icaridine, 2-octyl-2H-isothiazol-3-one (OIT), piperonyl butoxide (PBO), triclosan, tebuconazole, terbutryn and tetramethrin. Using data available from household product inventories of the two streets, we searched the lists of ingredients for the products possibly being responsible for the emissions. Except for four substances, all substances have been detected in at least 10% of the samples. Highest concentrations were measured for C₁₂-benzalkonium chloride with an average concentration in the daily samples of 7.7 μg/L in one of the streets. Next to C₁₂-benzalkonium chloride, BIT, DEET and icaridine were detected in all samples in average concentrations above 1 μg/L in at least one street. The results show that washing and cleaning agents were important sources for preservatives such as BIT and OIT, while triclosan was apparently mainly emitted through personal care products. The mosquito repelling substances DEET and icaridine were found throughout the year, with highest emissions in summer and autumn. In conclusion, the results demonstrate that the sources of biocidal active substances in municipal wastewater are complex and that measures for the prevention of the emission of biocidal active substances into the aquatic environment have to be carried out under different legislations. This has to be taken into account discussing emission reduction at the source.

The fate and risk assessment of psychiatric pharmaceuticals from psychiatric hospital effluent

Psychiatric pharmaceuticals are gaining public attention because of increasing reports of their occurrence in environment and their potential impact on ecosystems and human health. This work studied the occurrence and fate of 15 selected psychiatric pharmaceuticals from 3 psychiatric hospitals effluent in Shanghai and investigated the effect of hospitals effluent on surface water, groundwater, soil and plant. Amitriptyline (83.57ng) and lorazepam (22.26ng) showed the highest concentration and were found frequently in hospital effluent. Lorazepam (8.27ng), carbamazepine (83.80ng) and diazepam (79.33ng) showed higher values in surface water. The concentration of lorazepam (46.83ng) in groundwater was higher than other reports. Only six target compounds were detected in all three soil points in accordance with very low concentration. Alkaline pharmaceuticals were more easily adsorbed by soil. Carbamazepine (1.29ng) and lorazepam (2.95ngg^-1) were frequently determined in plant tissues. The correlation analyses (Spearman correlations > 0.5) showed the main source of psychiatric pharmaceuticals pollutants might be hospital effluents (from effluent to surface water; from surface water to groundwater). However, hospital effluents were not the only pollution sources from the perspective of the dilution factor analysis. Although the risk assessment indicated that the risk was low to aquatic organism, the continuous discharge of pollution might cause potential environment problem.

Pharmaceuticals released from senior residences: occurrence and risk evaluation

One of the main pursuits, yet most difficult, in monitoring studies is to identify the sources of environmental pollution. In this study, we have identified health-care facilities from south European countries as an important source of pharmaceuticals in the environment. We have estimated that compounds consumed in by the elderly and released from effluents of senior residences can reach river waters at a concentration higher than 0.01 μg/L, which is the European Medicines Agency (EMA) threshold for risk evaluation of pharmaceuticals in surface waters. This study has been based on five health institutions in Portugal, Spain, and France, with 52 to 130 beds. We have compiled the pharmaceuticals dispensed on a daily base and calculated the consumption rates. From 54.9 to 1801 g of pharmaceuticals are consumed daily, with laxatives, analgesics, antiepileptics, antibiotics, and antidiabetic agents being the main drug families administered. According to excretion rates, dilution in the sewerage system, and elimination in wastewater treatment plants, macrogol, metformin, paracetamol, acetylcysteine, amoxicillin, and gabapentin, among others, are expected to reach river waters. Finally, we discuss the risk management actions related to the discharge of pharmaceuticals from senior residences to surface waters.

Consumption-based approach for pharmaceutical compounds in a large hospital

Hospital wastewater contains a great variety of pharmaceutical compounds (PhCs), mainly due to excretion by patients. These PhCs, called emerging pollutants, are not fully eliminated in treatment plants, and are consequently detected in various environmental matrices, contributing to bacterial resistance and adverse environmental impacts on water resources. This study explores a consumption-based approach to predict the contribution of PhCs to a Brazilian hospital's wastewater. This approach identifies the consumption of major pharmaceutical classes in the studied hospital. Overall, this approach demonstrates a unique opportunity to screen PhCs used in hospitals and identify priority pollutants in hospital wastewater.

Initial fate assessment of teratogenic drug trimipramine and its photo-transformation products - Role of pH, concentration and temperature

Trimipramine (TMP) is an antidepressant drug used for the treatment of a variety of depressive states and other psychiatric disorders. It has been already detected in the aquatic environment. Currently, no further knowledge is available on fate and effects of TMP in the aquatic environment. Therefore, we studied the biodegradability of TMP and of its photolysis transformation products (PTPs) generated by irradiation with polychromatic UV light in aqueous solution. Different conditions including initial drug concentration, pH, and temperature were applied during TMP photolysis. Subsequently, the time courses of TMP and dissolved organic carbon (DOC) concentrations were monitored throughout the whole photo-degradation process. Then, high-resolution mass spectrometry was used to identify and elucidate the structures of the resulting PTPs. After that, the two standardized biodegradation tests, Closed Bottle test (CBT; OECD 301 D) and Manometric Respirometry test (MRT; OECD 301 F), were performed for TMP and its photolytic mixtures to assess the biodegradability of TMP and its PTPs. Finally, the toxicity of TMP and its photolytic mixtures was predicted using different quantitative structure activity relationship (QSAR) software. It was found that after 128 min of UV-irradiation, 91.8% of TMP at the initial concentration of 100 mg L^-1 was eliminated with only 23.9% removal in the DOC. So, it can be pointed out that more than 65% of the degraded TMP is transformed to new non-mineralized PTPs. 14 new PTPs were detected in TMP's photolytic mixtures. Their supposed structures indicate that the proposed photo-transformation pathway is mainly by hydroxylation. The statistical analysis confirms that the differences in the degradation rates of TMP as a function of concentration, pH, and temperature are statistically significant in most cases investigated here. In biodegradation testing, TMP and its PTPs are classified as not readily biodegradable, while LC-MS analysis revealed some PTPs to be eliminated more than TMP itself. Results from QSAR analysis confirmed that some of the PTPs could be biodegradable, and revealed that some of the non-biodegradable PTPs may be human and/or eco-toxic, posing a risk to the environment. Our findings show that TMP under UV-irradiation could lead to the formation of some more easily biodegradable PTPs and some others toxic and non-biodegradable PTPs. Therefore, further studies should be conducted regarding the fate and effects of TMP and its PTPs elucidated in this study on human health and on the environment.

Monitoring, sources, receptors, and control measures for three European Union watch list substances of emerging concern in receiving waters - A 20year systematic review

Pollution of European receiving waters with contaminants of emerging concern (CECs), such as with 17-beta-estradiol (a natural estrogenic hormone, E2), along with pharmaceutically-active compounds diclofenac (an anti-inflammatory drug, DCL) and 17-alpha-ethynylestradiol (a synthetic estrogenic hormone, EE2)) is a ubiquitous phenomenon. These three CECs were added to the EU watch list of emerging substances to be monitoring in 2013, which was updated in 2015 to comprise 10 substances/groups of substances in the field of water policy. A systematic literature review was conducted of 3952 potentially relevant articles over period 1995 to 2015 that produced a new EU-wide database consisting of 1268 publications on DCL, E2 and EE2. European surface water concentrations of DCL are typically reported below the proposed annual average environmental quality standard (AA EQS) of 100ng/l, but that exceedances frequently occur. E2 and EE2 surface water concentrations are typically below 50ng/l and 10ng/l respectively, but these values greatly exceed the proposed AA EQS values for these compounds (0.04 and 0.035ng/l respectively). However, levels of these CECs are frequently reported to be disproportionately high in EU receiving waters, particularly in effluents at control points that require urgent attention. Overall it was found that DCL and EE2 enter European aquatic environment mainly following human consumption and excretion of therapeutic drugs, and by incomplete removal from influent at urban wastewater treatment plants (WWTPs). E2 is a natural hormone excreted by humans which also experiences incomplete removal during WWTPs treatment. Current conventional analytical chemistry methods are sufficiently sensitive for the detection and quantification of DCL but not for E2 and EE2, thus alternative, ultra-trace, time-integrated monitoring techniques such as passive sampling are needed to inform water quality for these estrogens. DCL appears resistant to conventional wastewater treatment while E2 and EE2 have high removal efficiencies that occur through biodegradation or sorption to organic matter. There is a pressing need to determine fate and behaviour of these CECs in European receiving waters such as using GIS-modelling of river basins as this will identify pressure points for informing priority decision making and alleviation strategies for upgrade of WWTPs and for hospital effluents with advanced treatment technologies. More monitoring data for these CECs in receiving waters is urgently needed for EU legislation and effective risk management.

Experimental and in silico assessment of fate and effects of the antipsychotic drug quetiapine and its bio- and phototransformation products in aquatic environments

The antipsychotic drug quetiapine (QUT) has been frequently detected in sewage treatment plants. However, information on the fate of QUT in aquatic environments and its behavior during UV treatment is limited. In this study, QUT is shown not to be readily biodegradable in the Closed Bottle Test and the Manometric Respirometry Test according to OECD guidelines. The main biotransformation product (BTP) formed in the tests, a carboxylic acid derivative, was identified by means of high-resolution mass spectrometry. This BTP is presumably a human metabolite and showed higher detection rates than QUT in a river sampling campaign conducted in northern Germany. UV elimination kinetics of QUT at different initial concentrations (226.5, 45.3, 11.3, and 2.3 μmol L^-1) were faster at lower initial concentrations. All seven phototransformation products (PTPs) could be still identified at initial concentration of 11.3 μmol L^-1. The photolytic mixture generated after 128 min of photolysis of QUT was not better biodegradable than QUT. Initial UV treatment of QUT led to the formation of several additional BTPs. Four of them were identified. The bacterial cytotoxicity and genotoxicity before and after phototransformation of QUT in a modified luminescent bacteria test (LBT) and the umu-test (ISO/FDIS 13829) showed cytotoxic effects in the LBT for QUT. Furthermore, PTPs had similar cytotoxic effects on luminescent bacteria. The umu-test did not reveal any genotoxic activity for QUT or PTPs. In conclusion, the release of QUT into sewage treatment plants and aquatic environments could result in the formation of a main BTP. Additional UV treatment of QUT would lead to the formation of additional BTPs. Moreover, treatment did not result in lower toxicity to tested organisms. In conclusion, UV treatment of QUT should be considered critically as a potential treatment for QUT in aquatic systems.

Removal of Antibiotics in Biological Wastewater Treatment Systems-A Critical Assessment Using the Activated Sludge Modeling Framework for Xenobiotics (ASM-X)

Many scientific studies present removal efficiencies for pharmaceuticals in laboratory-, pilot-, and full-scale wastewater treatment plants, based on observations that may be impacted by theoretical and methodological approaches used. In this Critical Review, we evaluated factors influencing observed removal efficiencies of three antibiotics (sulfamethoxazole, ciprofloxacin, tetracycline) in pilot- and full-scale biological treatment systems. Factors assessed include (i) retransformation to parent pharmaceuticals from e.g., conjugated metabolites and analogues, (ii) solid retention time (SRT), (iii) fractions sorbed onto solids, and (iv) dynamics in influent and effluent loading. A recently developed methodology was used, relying on the comparison of removal efficiency predictions (obtained with the Activated Sludge Model for Xenobiotics (ASM-X)) with representative measured data from literature. By applying this methodology, we demonstrated that (a) the elimination of sulfamethoxazole may be significantly underestimated when not considering retransformation from conjugated metabolites, depending on the type (urban or hospital) and size of upstream catchments; (b) operation at extended SRT may enhance antibiotic removal, as shown for sulfamethoxazole; (c) not accounting for fractions sorbed in influent and effluent solids may cause slight underestimation of ciprofloxacin removal efficiency. Using tetracycline as example substance, we ultimately evaluated implications of effluent dynamics and retransformation on environmental exposure and risk prediction.

UV-photodegradation of desipramine: Impact of concentration, pH and temperature on formation of products including their biodegradability and toxicity

Desipramine (DMI) is a widely used tricyclic antidepressant, and it is the major metabolite of imipramine (IMI) and lofepramine (LMI); IMI and LMI are two of the most commonly used tricyclic antidepressants. If DMI enters the aquatic environment, it can be transformed by the environmental bacteria or UV radiation. Therefore, photolysis of DMI in water was performed using a simulated sunlight Xenon-lamp and a UV-lamp. Subsequently, the biodegradability of DMI and its photo-transformation products (PTPs) formed during its UV photolysis was studied. The influence of variable conditions, such as initial DMI concentration, solution pH, and temperature, on DMI UV photolysis behavior was also studied. The degree of mineralization of DMI and its PTPs was monitored. A Shimadzu HPLC-UV apparatus was used to follow the kinetic profile of DMI during UV-irradiation; after that, ion-trap and high-resolution mass spectrometry coupled with chromatography were used to monitor and identify the possible PTPs. The environmentally relevant properties and selected toxicity properties of DMI and the non-biodegradable PTPs were predicted using different QSAR models. DMI underwent UV photolysis with first-order kinetics. Quantum yields were very low. DOC values indicated that DMI formed new PTPs and was not completely mineralized. Analysis by means of high-resolution mass spectrometry revealed that the photolysis of DMI followed three main photolysis pathways: isomerization, hydroxylation, and ring opening. The photolysis rate was inversely proportional to initial DMI concentration. The pH showed a significant impact on the photolysis rate of DMI, and on the PTPs in terms of both formation kinetics and mechanisms. Although temperature was expected to increase the photolysis rate, it showed a non-significant impact in this study. Results from biodegradation tests and QSAR analysis revealed that DMI and its PTPs are not readily biodegradable and that some PTPs may be human and/or eco-toxic, so they may pose a risk to the environment.

Predicted and measured concentrations of pharmaceuticals in hospital effluents. Examination of the strengths and weaknesses of the two approaches through the analysis of a case study

This study deals with the chemical characterization of hospital effluents in terms of the predicted and measured concentrations of 38 pharmaceuticals belonging to 11 different therapeutic classes. The paper outlines the strengths and weaknesses of the two approaches through an analysis of a case study referring to a large hospital. It highlights the observed (and expected) ranges of variability for the parameters of the adopted model, presents the results of an uncertainty analysis of direct measurements (due to sampling mode and frequency and chemical analysis) and a sensitivity analysis of predicted concentrations (based on the annual consumption of pharmaceuticals, their excretion rate and annual wastewater volume generated by the hospital). Measured concentrations refer to two sampling campaigns carried out in summer and winter in order to investigate seasonal variability of the selected compounds. Predicted concentrations are compared to measured ones in the three scenarios: summer, winter and the whole year. It was found that predicted and measured concentrations are in agreement for a limited number of compounds (namely atenolol, atorvastatin and hydrochlorothiazide), and for most compounds the adoption of the model leads to a large overestimation in all three periods. Uncertainties in predictions are mainly due to the wastewater volume and excretion factor, whereas for measured concentrations, uncertainties are mainly due to sampling mode.

Possible underestimations of risks for the environment due to unregulated emissions of biocides from households to wastewater

The aim of this study was to investigate the role of household products as possible sources of biocidal active substances in municipal wastewater and their regulation under the Biocidal Products Regulation (EU) 528/2012. In 131 households, we investigated the prevalence of products used to control pests, washing and cleaning agents and select personal care products with high release to wastewater. Inventories of these products were established with the help of barcode scanning. All uses of biocidal active substances were evaluated regarding their assessment under the Biocidal Products Regulation. 2963 products were scanned in total, with 48% being washing and cleaning agents, 43% personal care products and 9% products used to control pests. Biocidal active substances were found in each household. These were observed primarily in washing and cleaning agents and personal care products (90%), while only a small percentage of the observations of biocidal active substances was in biocidal products. 64% of the observations of biocidal active substances were in applications that do not fall under the Biocidal Products Regulation and are thus not subject to its environmental risk assessment. This study shows clearly that risks for the environment are underestimated because unregulated emissions to wastewater occur. It demonstrates that there are gaps in the current chemical legislation that lead to a release of substances into wastewater that were not subject to environmental risk assessment under the Biocidal Products Regulation. This is one example of the limitations of scientific risk assessment of chemicals - its complexity is immense. From our point of view, the results underline the importance of a sustainable use of the substances as this is the only way to decrease yet unidentified risks.

Tracer tests and uncertainty propagation to design monitoring setups in view of pharmaceutical mass flow analyses in sewer systems

The development of a strategic approach to manage pollution of surface waters with pharmaceutical residues is in centre of interest in Europe. In this context a lack of reliable standard procedures for sampling and subsequent assessment of pharmaceutical mass flows in the water cycle has been identified. Authoritative assessment of relevant substance concentrations and flows is essential for environmental risk assessments and reliable efficiency analysis of measures to reduce or avoid emissions of drugs to water systems. Accordingly, a detailed preparation of monitoring campaigns including an accuracy check for the sampling configuration provides important information on the reliability of the gathered data. It finally supports data analysis and interpretation for evaluations of the efficiency of measures as well as for cost benefit assessments. The precision of mass flow balances is expected to be particularly weak when substances with high short-term variations and rare upstream emissions are considered. This is especially true for substance flow analysis in sewers close to source because of expectable highly dynamic flow conditions and emission patterns of pollutants. The case study presented here focusses on the verification of a monitoring campaign in a hospital sewer in Luxembourg. The results highlight the importance for a priori accuracy checks and provide a blueprint for well-designed monitoring campaigns of pharmaceutical trace pollutants on the one hand. On the other hand, the study provides evidence that the defined and applied continuous flow proportional sampling procedure enables a representative monitoring of short-term peak loads of the x-ray contrast media iobitridol close to source.