Pharmaceuticals In Wastewater Effluent Research Articles

Analysis of atorvastatin in environmental waters: Validation of an electrochemical molecularly imprinted polymer sensor with application of life cycle assessment

The widespread presence of pharmaceuticals in wastewater effluents after treatment stands as a significant challenge faced in the field of wastewater management and public health. Governments and the scientific community have worked to meet this urgent need for effective solutions. Nevertheless, the development of detection strategies for pharmaceutical monitorization capable of delivering rapid, on-site, and sensitive responses remains an ongoing necessity. In this work, the performance of a previously developed molecularly imprinted polymer (MIP) based electrochemical sensor for detecting atorvastatin (ATV) in wastewater effluents and surface waters is presented. A simple preconcentration method followed by electrochemical measurements by differential pulse voltammetry (DPV) in 0.1 M phosphate buffer (pH = 7), was implemented. The analytical results were validated with those obtained on a set of 16 water samples by ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). Additionally, a life cycle assessment (LCA) was conducted to compare the environmental impact of both methodologies. The results obtained demonstrated that ATV detection using MIP-sensor was reliable when compared to the results found by UHPLC-MS/MS presenting a robust linear correlation coefficient of 0.843. The LCA results show that the novel MIP-sensor technique has lower associated environmental impacts than UHPLC-MS/MS, when the current analytical protocol for pharmaceuticals detection is applied. These findings highlight the potential of the developed MIP-sensor as an eco-friendly analytical tool for routine analysis and point-of-care monitoring of ATV in WWTP wastewater and surface water samples.

Ecotoxicological mixture risk assessment of 35 pharmaceuticals in wastewater effluents following post-treatment with ozone and/or granulated activated carbon

Reducing the risk posed by mixtures of pharmaceuticals is a goal of current initiatives such as the European Green Deal to reduce anthropological environmental impacts. Wastewater effluent typically contains large numbers of active pharmaceutical ingredients (APIs). For some APIs, existing technology such as conventional activated sludge (CAS) wastewater treatment plants (WWTPs) have removal rates below 20 %, thus the WWTP discharges are adding to the toxic burden of receiving waters.We present an environmental risk assessment of mixtures of 35 APIs in effluent samples from 82 Northern European WWTPs using the concentration addition model, and identify the respective risk-driving APIs. This is then compared to a corresponding mixture risk assessment of effluent samples from the Danish Hillerød WWTP subjected to post-treatment with varying specific ozone doses (0.15–1.05 mgO3/mgDOC) and/or granulated activated carbon (GAC).All 82 WWTP effluent samples exceeded risk thresholds by at least a factor of 30, with a median RQSUM of 92.9, highlighting the need for effluent post-treatment and/or a substantial dilution in the recipient waters. Antibiotics, analgesics and anti-depressants were among the top risk drivers with 99 % of the average mixture risk attributable to azithromycin, diclofenac, venlafaxine, clarithromycin and mycophenolic acid. Effluent mixture risk was reduced by ozonation in a concentration-dependent manner, decreasing below threshold levels to a median RQSUM of 0.83 following treatment with 0.65 mgO3/mg DOC. Fresh GAC was also effective at reducing the mixture risk both alone and with ozone treatment, with median RQSUM of 0.04 and 0.07 respectively.To our knowledge, this is the first study to present a risk assessment of pharmaceutical mixtures in effluent comparing “conventional” WWTP processes with additional post-treatment with ozone and/or GAC for reducing the joint risks of pharmaceutical mixtures for recipient waters. We demonstrate the need for additional WWTP treatment technologies, and the efficacy of GAC and ozonation in decreasing the risk to the aquatic environment from pharmaceutical mixtures to below acceptable threshold limits.

Investigating the Effects of Venlafaxine on Oxidative Stress and Exploring its Relationship to Neurodegenerative Disease

The rise in presence of pharmaceuticals in wastewater effluent has had behavioural effects on fish, which this study aimed to investigate.⁴ The pharmaceutical studied was venlafaxine (VEN), a commonly prescribed antidepressant.⁴ Previous studies have shown that venlafaxine contributes to oxidative stress.³ Notably, oxidative stress has been linked to neurodegeneration and plays a role in the pathogenesis of neurodegenerative diseases, such as Alzheimer’s, and Parkinson’s in humans.¹
 This study applied a novel approach through in vitro methods to directly expose zebrafish brains to varying VEN concentrations (0.01, 0.1, and 1 μg/L) and quantify oxidative stress. Zebrafish brains were used due to their neuroanatomical similarity to humans.¹⁴ Results demonstrated decreases in cell viability, and increases in antioxidant enzyme activity (catalase and superoxide dismutase) with rising concentrations of VEN.
 These findings demonstrate increases in oxidative stress, which was indirectly measured by antioxidant enzyme activity, as well as the effects of VEN on cell viability and protein amounts in the brain cells. These results indicate a possible link between venlafaxine exposure and increased risk of neurodegeneration in humans. Further investigation should be done to examine the association between venlafaxine concentrations in water and increased incidence of neurodegenerative disease in mammalian brains.

Impacts of COVID-19 pandemic on the aquatic environment associated with disinfection byproducts and pharmaceuticals

In this study, concentrations of disinfection byproducts (DBPs) and COVID-19 related pharmaceuticals in wastewater effluents and surface water were measured two weeks, three months and eight months after the lockdown in Wuhan. Little temporal variation in DBP concentrations suggested intensified disinfection during the COVID-19 pandemic had limited impacts on the occurrence of DBPs in the aquatic environment. In contrast, the pandemic led to a significant increase in concentrations of lopinavir and ritonavir in wastewater effluents and surface water. The high detection frequency of these pharmaceuticals in surface water after the lockdown highlighted their mobility and persistence in the aquatic environment. The initial ecological risk assessment indicated moderate risks associated with these pharmaceuticals in surface water. As the global situation is still rapidly evolving with a continuous surge in the number of confirmed COVID-19 cases, our results suggest a pressing need for monitoring COVID-19 related pharmaceuticals as well as a systematic evaluation of their ecotoxicities in the aquatic environment.

Development of fluorescence surrogates to predict the ferrate(VI) oxidation of pharmaceuticals in wastewater effluents

The removal of pharmaceuticals from wastewater effluents is an emerging concern for environmental scientists and engineers. Ferrate(VI) (FeVIO42−, FeVI) is a promising oxidant and the removal of pharmaceuticals from wastewater effluents has been investigated in this study. Firstly, FeVI oxidation of selected pharmaceuticals was examined by determining the apparent second-order rate constants (kapp) in buffer solutions as a function of pH (5.0–9.5). At pH 8.0, kapp of cimetidine, famotidine, nalidixic acid, ronidazole, dimetridazole, tinidazole, and caffeine are (1.6 ± 0.2)×103, (7.8 ± 0.3)×102, 2.6 ± 0.4, 1.7 ± 0.1, 0.9 ± 0.3, 0.2 ± 0.1, and < 0.1 M−1 s−1, respectively. However, kapp could not be directly employed to predict the removal of pharmaceuticals in the effluents due to the inhibited or enhanced effects of effluent organic matters (EfOM). Therefore, an alternative approach of spectroscopic surrogates was investigated since fluorophore was co-degraded with pharmaceuticals in the wastewater effluents. Particularly, the humic-like fluorescent peak correlated well with the pharmaceutical attenuation. The relationship of the reduction of fluorescence and the removal of pharmaceuticals could be described through a universal equation: y=A1xk1kw+A2xk2kw+A3. The practical utility of the fluorescence surrogate was validated by applying to field samples. Monitoring the changes of the fluorescence surrogate provides a promising, rapid, and inexpensive method for estimating the degradation of pharmaceuticals during FeVI treatment of wastewater effluents.

Detection of pharmaceuticals in wastewater effluents\u2014a comparison of the performance of Chemcatcher\xae and polar organic compound integrative sampler

Chemcatcher® and POCIS passive sampling devices are widely used for monitoring polar organic pollutants in water. Chemcatcher® uses a bound Horizon Atlantic™ HLB-L sorbent disk as receiving phase, whilst the POCIS uses the same material in the form of loose powder. Both devices (n = 3) were deployed for 21 days in the final effluent at three wastewater treatment plants in South Wales, UK. Following deployment, sampler extracts were analysed using liquid chromatography time-of-flight mass spectrometry. Compounds were identified using an in-house database of pharmaceuticals using a metabolomics workflow. Sixty-eight compounds were identified in all samplers. For the POCIS, substantial losses of sorbent (11–51%) were found during deployment and subsequent laboratory analysis, necessitating the use of a recovery factor. Percentage relative standard deviations varied (with 10 compounds exceeding 30% in both samplers) between individual compounds and between samplers deployed at the three sites. The relative performance of the two devices was evaluated using the mass of analyte sequestered, measured as an integrated peak area. The ratio of the uptake of the pharmaceuticals for the POCIS versus Chemcatcher® was lower (1.84x) than would be expected on the basis of the ratio of active sampling areas (3.01x) of the two devices. The lower than predicted uptake may be attributable to the loose sorbent material moving inside the POCIS when deployed in the field in the vertical plane. In order to overcome this, it is recommended to deploy the POCIS horizontally inside the deployment cage.

Sale-based estimation of pharmaceutical concentrations and associated environmental risk in the Japanese wastewater system

Information on sales and emission of selected pharmaceuticals were used to predict their concentrations in Japanese wastewater influent through a >300 of pharmaceuticals data sink. A combined wastewater-based epidemiology and environmental risk analysis follow was established. By comparing predicted environmental concentrations (PECs) of pharmaceuticals in wastewater influent against measured environmental concentrations (MECs) reported in previous studies, it was found that the model gave accurate results for 17 pharmaceuticals (0.5 < PEC/MEC < 2), and acceptable results for 32 out of 40 pharmaceuticals (0.1 < PEC/MEC < 10). Although the majority of pharmaceuticals considered in the model were antibiotics and analgesics, pranlukast, a receptor antagonist, was predicted to have the highest concentration in wastewater influent. With regard to the composition of wastewater effluent, the Estimation Program Interface (EPI) suite was used to predict pharmaceutical removal through activated sludge treatment. Although the performance of the EPI suite was variable in terms of accurate prediction of the removal of different pharmaceuticals, it could be an efficient tool in practice for predicting removal under extreme scenarios. By using the EPI suite with input data on PEC in the wastewater influent, the PEC values of pharmaceuticals in wastewater effluent were predicted. The concentrations of 26 pharmaceuticals were relatively high (>1 μg/L), and the PECs of 6 pharmaceuticals were extremely high (>10 μg/L) in wastewater effluent, which could be attributed to their high usage rates by consumers and poor removal rates in wastewater treatment plants (WWTPs). Furthermore, environmental risk assessment (ERA) was carried out by calculating the ratio of predicted no effect concentration (PNEC) to PEC of different pharmaceuticals, and it was found that 9 pharmaceuticals were likely to have high toxicity, and 54 pharmaceuticals were likely to have potential toxicity. It is recommended that this is further investigated in detail. The priority screening and environmental risk assessment results on pharmaceuticals can provide reliable basis for policy-making and environmental management.

Removal efficiencies of top-used pharmaceuticals at sewage treatment plants with various technologies

The presence of pharmaceuticals in wastewater and the environment has attracted growing public concern. Although studies have been performed to detect pharmaceuticals in wastewater effluents, little research has been conducted to assess the efficiency of pharmaceutical removal using different treatment technologies. To assess the removal efficiencies of pharmaceuticals in wastewater, samples from 22 municipal treatment plants in Nova Scotia and New Brunswick were analyzed for 12 commonly used pharmaceuticals and 2 primary metabolites. The medians of removal efficiencies for 9 technologies: aerated lagoon, extended aeration, facultative lagoon, membrane bioreactor, modified secondary, oxidation ditch, primary treatment, rotating biological contactor, and sequencing batch reactor technologies, were determined to be 98.0%, 96.4%, 98.2%, 99.8%, 68.4%, 99.0%, 3.0%, 81.3%, and 98.3%, respectively. The medians of removal efficiencies of individual pharmaceuticals were found from -14.4% to 100%. Primary treatment showed significant differences comparing to other treatment technologies. Very strong correlations of removal efficiencies were found between acetaminophen and warfarin, between cotinine and warfarin, between cotinine and paraxanthine, and between ramipril and atorvastatin. In general, there was no strong correlation of removal between pharmaceuticals and total organic waste load or total suspended solids.

Efficient degradation of pharmaceutical micropollutants in water and wastewater by FeIII-NTA-catalyzed neutral photo-Fenton process

Ferric-nitrilotriacetate complex (FeIII-NTA) has been adopted to catalyze the photo-Fenton degradation of emerging pharmaceutical micropollutants in water and wastewater at neutral pH. The generation of hydroxyl radicals (HO) in UVA/FeIII-NTA/H2O2 was identified by using electron spin resonance (ESR) trapping technique. The effects of critical parameters (e.g., NTA:FeIII molar ratio, FeIII-NTA and H2O2 dosages) on the steady-state HO concentrations were studied in terms of the degradation of carbamazepine (CBZ, as a model compound) in Milli-Q water. In addition, the degradation of pharmaceuticals mixtures (including CBZ, crotamiton (CRMT) and ibuprofen (IBP)) in wastewater effluents from a biological aerated filter (BAF) by UVA/FeIII-NTA/H2O2 was studied in continuous-flow mode. The results showed that the efficacies of FeIII-NTA in catalyzing photo-Fenton degradation of pharmaceuticals in wastewater effluents were comparable to those obtained by FeIII-ethylenediamine-N,N′-disuccinic acid (FeIII-EDDS), and far exceeded other FeIII-L complex (e.g., citric acid, malonic acid, oxalic acid and tartaric acid). More than 92% degradation efficiencies of CBZ, CRMT and IBP were obtained in continuous-flow mode under the given conditions of 0.178 mM FeIII-NTA (1:1), 4.54 mM H2O2, UVA intensity 4.05 mW cm−2, hydraulic retention time (HRT) 2 h, influent pH 7.6 (±0.2) and temperature 20 °C. The results presented herein suggest that FeIII-NTA-catalyzed neutral photo-Fenton reaction can be an alternative tertiary process for the treatment of pharmaceutical micropollutants in secondary wastewater effluents.

A critical evaluation of different parameters for estimating pharmaceutical exposure seeking an improved environmental risk assessment

A critical evaluation of the European Medicines Agency (EMA) Guideline on Environmental Risk Assessment (ERA) was performed on 16 of Portugal's most consumed pharmaceuticals in wastewater effluents (WWEs), the main route for aquatic contamination. The predicted environmental concentrations (PECs) were formulated based on the Guideline, after incorporating several refinements. The best approach was selected by comparing the measured environmental concentrations (MECs) to the PECs in WWEs. Finally, risk was assessed by comparing PECs to predicted no-effect concentrations (PNECs).The results showed that the default value of the penetration factor (Fpen) used by the EMA (0.01) was surpassed and that national consumption and excretion data were the two most important parameters for PEC calculations. The risk quotient between PECs and PNECs was higher than 1 for 12 pharmaceuticals, indicating a risk to all three trophic levels of aquatic organisms (algae, daphnids and fish).To improve the current ERA framework, suggestions were made for incorporating consumption and excretion data, changing the default value of Fpen to 0.04 and adding a safety factor of 10. Moreover, this evaluation should be performed for pharmaceuticals already on the market, and future ERAs should incorporate a risk-benefit analysis, an important risk-management step.

Development of Fluorescence Surrogates to Predict the Photochemical Transformation of Pharmaceuticals in Wastewater Effluents.

The photochemical transformation of pharmaceutical and personal care products (PPCPs) in wastewater effluents is an emerging concern for environmental scientists. In the current study, the photodegradation of 29 PPCPs was examined in effluents under simulated solar irradiation. Direct photodegradation, triplet state effluent organic matter (3EfOM*)-mediated and hydroxyl radical (HO•)-mediated degradation are three major pathways in the removal process. With the photodegradation of trace levels of PPCPs, the excitation-emission matrix (EEM) fluorescence intensities of the effluents were also gradually reduced. Therefore, fluorescence peaks have been identified, for the first time, as appropriate surrogates to assess the photodegradation of PPCPs. The humic-like fluorescence peak is linked to direct photolysis-labile PPCPs, such as naproxen, ronidazole, diclofenac, ornidazole, tinidazole, chloramphenicol, flumequine, ciprofloxacin, methadone, and dimetridazole. The tyrosine-like EEM peak is associated with HO•/CO3•--labile PPCPs, such as trimethoprim, ibuprofen, gemfibrozil, atenolol, carbamazepine, and cephalexin. The tryptophan-like peak is associated with 3EfOM*-labile PPCPs, such as clenbuterol, metoprolol, venlafaxine, bisphenol A, propranolol, ractopamine, salbutamol, roxithromycin, clarithromycin, azithromycin, famotidine, terbutaline, and erythromycin. The reduction in EEM fluorescence correlates well with the removal of PPCPs, allowing a model to be constructed. The solar-driven removal of EEM fluorescence was applied to predict the attenuation of 11 PPCPs in five field samples. A close correlation between the predicted results and the experimental results suggests that fluorescence may be a suitable surrogate for monitoring the solar-driven photodegradation of PPCPs in effluents.

Kinetic Study of Hydroxyl and Sulfate Radical-Mediated Oxidation of Pharmaceuticals in Wastewater Effluents.

Advanced oxidation processes (AOPs), such as hydroxyl radical (HO•)- and sulfate radical (SO4•-)-mediated oxidation, are alternatives for the attenuation of pharmaceuticals and personal care products (PPCPs) in wastewater effluents. However, the kinetics of these reactions needs to be investigated. In this study, kinetic models for 15 PPCPs were built to predict the degradation of PPCPs in both HO•- and SO4•--mediated oxidation. In the UV/H2O2 process, a simplified kinetic model involving only steady state concentrations of HO• and its biomolecular reaction rate constants is suitable for predicting the removal of PPCPs, indicating the dominant role of HO• in the removal of PPCPs. In the UV/K2S2O8 process, the calculated steady state concentrations of CO3•- and bromine radicals (Br•, Br2•- and BrCl•-) were 600-fold and 1-2 orders of magnitude higher than the concentrations of SO4•-, respectively. The kinetic model, involving both SO4•- and CO3•- as reactive species, was more accurate for predicting the removal of the 9 PPCPs, except for salbutamol and nitroimidazoles. The steric and ionic effects of organic matter toward SO4•- could lead to overestimations of the removal efficiencies of the SO4•--mediated oxidation of nitroimidazoles in wastewater effluents.

하수처리수를 이용한 대수층 함양관리 기술(Managed Aquifer Recharge)에서 유기물과 의약화합물 제거

하수처리수를 이용한 대수층 함양관리 기술(Managed Aquifer Recharge)에서 유기물과 의약화합물 제거

Chronic exposures to low and high concentrations of ibuprofen elicit different gene response patterns in a euryhaline fish.

Ibuprofen is one of the most commonly detected pharmaceuticals in wastewater effluent; however, the effects of ibuprofen on aquatic organisms are poorly understood. This study presents the transcriptome-wide response of the inland silverside, Menidia beryllina, to chronic exposure to ibuprofen. At the lowest exposure concentration (0.0115 mg/L), we detected a downregulation of many genes involved in skeletal development, aerobic respiration, and immune function. At the highest exposure concentration (1.15 mg/L), we detected increased expression of regulatory genes in the arachidonic acid metabolism pathway and several immune genes involved in an inflammatory response. Additionally, there was differential expression of genes involved in oxidative stress responses and a downregulation of genes involved in osmoregulation. This study provides useful information for monitoring the effects of this common wastewater effluent contaminant in the environment and for the generation of biomarkers of exposure to ibuprofen that may be transferable to other fish species.

Enhanced degradation of persistent pharmaceuticals found in wastewater treatment effluents using TiO2 nanobelt photocatalysts

Pharmaceuticals in wastewater effluents are a current and emerging global problem and the development of cost-effective methods to facilitate their removal is needed to mitigate this issue. Advanced oxidation processes (AOPs), in particular UV/TiO2, have potential for wastewater treatment. In this study, TiO2 anatase phase nanobelts (30–100 nm in width and 10 μm in length) have been synthesized using a high temperature hydrothermal method as a means to photocatalyze the oxidation of pharmaceutical contaminants. We have investigated a model dye (malachite green), three pharmaceuticals and personal care products—naproxen, carbamazepine, and theophylline—that are difficult to oxidize without AOP processes. TiO2 nanobelts were exposed to 365 nm UV illumination and the measured photocatalytic degradation rates and adsorption parameters of pharmaceuticals were explored using kinetic models. Furthermore we have determined the degree of pharmaceutical degradation as a function of solution pH, illumination time, temperature, and concentration of contaminant. In addition, the roles of active oxygen species—hydroxyl radial (OH·), positive holes (h+), and hydrogen peroxide (H2O2)—involved were also investigated in the degradation process. These studies offer additional applications of hierarchical TiO2 nanobelt membranes, including those harnessing sunlight for water treatment.

Degradation Kinetics and Metabolites of Carbamazepine in Soil

The antiepileptic drug carbamazepine (CBZ) is one of the most frequently detected human pharmaceuticals in wastewater effluents and biosolids. Soil is a primary environmental compartment receiving CBZ through wastewater irrigation and biosolid application. In this study, we explored the transformation of CBZ to biologically active intermediates in soil. Both (14)C labeling and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to track transformation kinetics and identify major degradation intermediates. Through 120 days of incubation under aerobic conditions, mineralization of CBZ did not exceed 2% of the spiked rate in different soils. Amendment of biosolids further suppressed mineralization. The fraction of non-extractable (i.e., bound) residue also remained negligible (<5%). On the other hand, CBZ was transformed to a range of degradation intermediates, including 10,11-dihydro-10-hydroxycarbamazepine, carbamazepine-10,11-epoxide, acridone-N-carbaldehyde, 4-aldehyde-9-acridone, and acridine, of which acridone-N-carbaldehyde was formed in a large fraction and appeared to be recalcitrant to further degradation. Electrocyclization, ring cleavage, hydrogen shift, carbonylation, and decarbonylation contributed to CBZ transformative reactions in soil, producing biologically active products. The persistence of the parent compound and formation of incomplete intermediates suggest that CBZ has a high risk for off-site transport from soil, such as accumulation into plants and contamination of groundwater.

The occurrence of human pharmaceuticals in wastewater effluents and surface water of Langat River and its tributaries, Malaysia

This study provides the first investigation on the occurrence of human pharmaceuticals in the tropical aquatic environment of Malaysia. Water samples were collected at seven different sites along the Langat River and effluents from five sewage treatment plants (STPs) in Langat River Basin. Samples were extracted by solid phase extraction (SPE) and analyzed using liquid chromatography coupled with a tandem mass spectrometry (LC-MS/MS) for 18 pharmaceuticals from six therapeutic classes and one metabolite. Fifteen out of these 19 pharmaceuticals were detected in the river water samples. Mefenamic acid, salicylic acid and glibenclamide were detected in all river water samples indicating their ubiquitous nature and resistance to degradation under the warm and humid tropical conditions. The median concentrations of detected pharmaceuticals ranged from less than the method detection limit (<MDL) for furosemide, loratadine, salbutamol, perindopril, metoprolol and nifedipine to 112.7 ng L−1 for diclofenac. A similar number of pharmaceuticals were detected in the STPs’ effluents samples. Several of these pharmaceuticals, namely salbutamol, atenolol, metoprolol, mefenamic acid, salicylic acid and furosemide were detected in all the STPs’ effluents samples. The median concentrations for the detected pollutants ranged between <MDL for lovastatin and amlodipine to 1994 ng L−1 for metformin. The highest concentration detected in the river water samples was for acetaminophen (346.3 ng L−1) and in STPs effluents was for metformin (34228 ng L−1). The concentrations of most analytes found in this study were comparable to those reported in the other parts of the world. However, this is the first time amlodipine is detected in the environmental samples.

A comparison of the chronic effects of human pharmaceuticals on two cladocerans, Daphniamagna and Ceriodaphniadubia

Scientific researchers and regulators are focusing attention on trace quantities of pharmaceuticals in wastewater effluents and surface waters, resulting in an increased level of concern regarding the potential environmental impact of these compounds. The current European regulatory guideline requires evaluation of the chronic effects of active pharmaceutical ingredients on Daphnia magna. Based on the life cycle of D. magna, chronic studies to establish survival and reproductive endpoints require a 21 d exposure period. A similar organism, Ceriodaphnia dubia, has a shorter life cycle and therefore survival and reproductive endpoints may be established following 7 d of exposure. No observed effect concentrations and lowest observed effect concentrations for survival and reproduction were obtained for D. magna and C. dubia following exposure to six human pharmaceuticals and two metabolites (i.e. celecoxib, linezolid, varenicline, sunitinib, Compound A, ziprasidone and the M1 and M4 metabolites of torcetrapib). These data were evaluated to determine whether one organism may be considered more sensitive. Survival and reproduction data obtained from the C. dubia study provide similar outcomes to D. magna when determining the predicted environmental concentration/predicted no effect concentration (PEC/PNEC) ratios for surface water. Based on these data, C. dubia may be used as a cost-effective alternative and representative invertebrate species when assessing the potential risk of human pharmaceuticals.

The occurrence of illicit and therapeutic pharmaceuticals in wastewater effluent and surface waters in Nebraska

The occurrence and estimated concentration of twenty illicit and therapeutic pharmaceuticals and metabolites in surface waters influenced by wastewater treatment plant (WWTP) discharge and in wastewater effluents in Nebraska were determined using Polar Organic Chemical Integrative Samplers (POCIS). Samplers were installed in rivers upstream and downstream of treated WWTP discharge at four sites and in a discharge canal at a fifth location. Based on differences in estimated concentrations determined from pharmaceuticals recovered from POCIS, WWTP effluent was found to be a significant source of pharmaceutical loading to the receiving waters. Effluents from WWTPs with trickling filters or trickling filters in parallel with activated sludge resulted in the highest observed in-stream pharmaceutical concentrations. Azithromycin, caffeine, 1,7-dimethylzanthine, carbamazepine, cotinine, DEET, diphenhydramine, and sulfamethazine were detected at all locations. Methamphetamine, an illicit pharmaceutical, was detected at all but one of the sampling locations, representing only the second report of methamphetamine detected in WWTP effluent and in streams impacted by WWTP effluent.

The occurrence of selected pharmaceuticals in wastewater effluent and surface waters of the lower Tyne catchment

This paper presents the results of a survey of the wastewater effluent and surface waters of the lower river Tyne, UK. Samples were analysed by reversed-phase high-performance liquid chromatography–electrospray tandem mass spectrometry following solid phase extraction, for the presence of 13 pharmaceuticals selected from the priority lists of the UK Environment Agency and the Oslo and Paris Commission (OSPAR). The pharmaceutical compounds measured were acetyl-sulfamethoxazole, clofibric acid, clotrimazole, dextropropoxyphene, diclofenac, erythromycin, ibuprofen, mefenamic acid, paracetamol, propranolol, sulfamethoxazole, tamoxifen and trimethoprim. Of the wastewater treatment works (WTW) samples ( n = 9) analysed, all compounds except sulfamethoxazole and acetyl-sulfamethoxazole were detected at concentrations ranging from 11 to 69,570 ng l − 1 (in raw effluent). In the surface water samples ( n = 18), clotrimazole, dextropropoxyphene, erythromycin, ibuprofen, propranolol, tamoxifen and trimethoprim were detected at concentrations ranging from 4 to 2370 ng l − 1 . Results of this study show that various pharmaceutical compounds are effectively reduced during their passage through a tertiary wastewater treatment works, whilst others are sufficiently persistent to occur in estuarine systems.