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.

Accumulation of polyethylene microplastics in river biofilms and effect on the uptake, biotransformation and toxicity of the antimicrobial triclosan.

The interaction of multiple stressors in freshwater ecosystems may lead to adverse effects on aquatic communities and their ecological functions. Microplastics (MPs) are a class of contaminants of emerging concern that can exert both direct and indirect ecotoxicological effects. A growing number of studies have investigated MPs-attached microbial communities, but the interaction between MPs and substrate-associated biofilm (i.e., on natural river substrates, such as stones and sediments) remains poorly studied. In this work, the combined effects of polyethylene MPs (PE-MPs) with a particle size of 10-45 µm (2 mg/L) and the antimicrobial triclosan (TCS) (20 µg/L) were investigated on river biofilms through a short-term exposure experiment (72 h). To the best of authors' knowledge, this is the first time that the combined effects of MPs and chemical contaminants in substrate-associated river biofilms were assessed. Different response parameters were evaluated, including (i) exposure assessment and ii) contaminants effects at different levels: bacterial community composition, antibiotic resistance, extracellular polymeric substances (EPS), photosynthetic efficiency (Yeff), and leucine aminopeptidase activity (LAPA). Triclosan was accumulated in river biofilms (1189-1513 ng/g dw) alongside its biotransformation product methyl-triclosan (20-29 ng/g dw). Also, PE-MPs were detected on biofilms (168-292 MP/cm2), but they had no significant influence on the bioaccumulation and biotransformation of TCS. A moderate shift in bacterial community composition was driven by TCS, regardless of PE-MPs co-exposure (e.g., increased relative abundance of Sphingomonadaceae family). Additionally, Yeff and EPS content were significantly disrupted in TCS-exposed biofilms. Therefore, the most remarkable effects on river biofilms were related to the antimicrobial TCS, whereas single PE-MPs exposure did not alter any of the evaluated parameters. These results demonstrate that biofilms might act as environmental sink of MPs. Although no interaction between PE-MPs and TCS was observed, the possible indirect impact of other MPs-adsorbed contaminants on biofilms should be further assessed.

Floating plastics as integrative samplers of organic contaminants of legacy and emerging concern from Western Mediterranean coastal areas.

This study investigates the role of floating plastics as integrative samplers of organic contaminants. To this end, plastics items were collected in two Western Mediterranean coastal areas: the Mar Menor lagoon, and the last transect of Ebro river. Floating plastics were identified and characterized by attenuated total reflection Fourier-transform infrared spectrometry. Then, organic contaminants were extracted from plastic items by ultrasonic extraction with methanol, and the concentrations of 168 regulated and emerging contaminants were analysed. These compounds were analysed by stir bar sorptive extraction coupled to gas chromatography-mass spectrometry (GC-MS), except for bisphenol analogues, which were analysed with a ultraperformance liquid chromatography pump coupled to a triple quadrupole mass spectrometer (UHPLC-MS/MS), and pharmaceutical compounds, determined by UPLC coupled to hybrid triple quadrupole-linear ion trap mass spectrometer (UPLC-MS/MS). All the contaminants groups considered were detected in the samples, being particularly relevant the contribution of plastic additives. The most frequently detected contaminants were UV-filters, PAHs, pharmaceuticals and synthetic musks. Apart from plasticizers, the individual contaminants octocrylene, homosalate, galaxolide, salycilic acid and ketoprofen were frequently detected in plastics items. The results pointed out to urban and touristic activities as the main sources of pollution in the coastal areas investigated. The utility of floating plastics as integrative samplers for the detection of organic contaminants in aquatic ecosystems has been demonstrated.

First evidence of environmental bioaccumulation of pharmaceuticals on adult native anurans (Rhinella arenarum) from Argentina.

The presence of pharmaceutically active compounds (PhACs) in surface water is well known, whereas their natural occurrence in biota is much less explored. The aim of this work was to evaluate the bioaccumulation of PhACs in adult toads of the neotropical species Rhinella arenarum. Three sites were selected in Buenos Aires (Argentina): a reference site (Site 1), a site with direct discharge from a secondary wastewater treatment plant (WWTP) (Site 2) and a site 300 m downstream of the WWTP discharge (Site 3). Surface water samples, as well as muscle, liver and fat bodies of toads were collected, extracted and analyzed by LC-MS/MS. Highly significant differences in total PhACs concentration in surface water (p < 0.005) were detected between Site 2 and the other sites. These concentrations ranged from 0.37 to 52.46 ng/L at Site 1, 0.71-6950.37 ng/L at Site 2, and 0.12-75.45 ng/L at Site 3. In general, bioaccumulation of PhACs in toad tissues was similar between sites and tissues of each site. The highest concentrations were detected in the muscle of toads from Site 3 (1.06-87.24 ng/g dw), followed by liver (1.77-38.10 ng/g dw) and fat bodies (0.68-20.59 ng/g dw) from Site 1. Ibuprofen (6950 ng/L), acetaminophen (3277 ng/L) and valsartan (2504 ng/L) were the compounds with the highest concentrations in surface water from Site 2, whereas acetaminophen (87.2 ng/g dw, muscle from Site 3), desloratadine (38.1 ng/g dw, liver from Site 1), and phenazone (25.9 ng/g dw, liver from Site 1) were the ones that showed the highest concentrations in biota. This is the first time a field study has examined the environmental bioaccumulation of PhACs in anurans, demonstrating their potential for monitoring the status of natural ecosystems.

Combined exposure of the bivalve Mytilus galloprovincialis to polyethylene microplastics and two pharmaceuticals (citalopram and bezafibrate): Bioaccumulation and metabolomic studies.

Pharmaceuticals and microplastics constitute potential hazards in aquatic systems, but their combined effects and underlying toxicity mechanisms remain largely unknown. In this study, a simultaneous characterization of bioaccumulation, associated metabolomic alterations and potential recovery mechanisms was performed. Specifically, a bioassay on Mediterranean mussels (Mytilus galloprovincialis) was carried out with polyethylene microplastics (PE-MPLs, 1 mg/L) and citalopram or bezafibrate (500 ng/L). Single and co-exposure scenarios lasted 21 days, followed by a 7-day depuration period to assess their potential recovery. PE-MPLs delayed the bioaccumulation of citalopram (lower mean at 10 d: 447 compared to 770 ng/g dw under single exposure), although reaching similar tissue concentrations after 21 d. A more limited accumulation of bezafibrate was observed overall, regardless of PE-MPLs co-exposure (

Bioaccumulation and fate of pharmaceuticals in a Mediterranean coastal lagoon: Temporal variation and impact of a flash flood event.

Coastal ecosystems are particularly vulnerable to terrestrial inputs from human-impacted areas. The prevalence of wastewater treatment plants, unable to remove contaminants such as pharmaceuticals (PhACs), leads to their continuous input into the marine environment. In this paper, the seasonal occurrence of PhACs in a semi-confined coastal lagoon (the Mar Menor, south-eastern Spain) was studied during 2018 and 2019 by evaluating their presence in seawater and sediments, and their bioaccumulation in aquatic organisms. Temporal variation in the contamination levels was evaluated by comparison to a previous study carried out between 2010 and 2011 before the cessation of permanent discharges of treated wastewater into the lagoon. The impact of a flash flood event (September 2019) on PhACs pollution was also assessed. A total of seven compounds (out of 69 PhACs analysed) were found in seawater during 2018-2019, with a limited detection frequency (<33%) and concentrations (up to 11 ng/L of clarithromycin). Only carbamazepine was found in sediments (ND-1.2 ng/g dw), suggesting an improved environmental quality in comparison to 2010-2011 (when 24 and 13 compounds were detected in seawater and sediments, respectively). However, the biomonitoring of fish and molluscs showed a still remarkable accumulation of analgesic/anti-inflammatory drugs, lipid regulators, psychiatric drugs and ß-blocking agents, albeit not higher than in 2010. The flash flood event from 2019 increased the prevalence of PhACs in the lagoon, compared to the 2018-2019 sampling campaigns, especially in the upper water layer. After the flash flood the antibiotics clarithromycin and sulfapyridine yielded the highest concentrations ever reported in the lagoon (297 and 145 ng/L, respectively), alongside azithromycin in 2011 (155 ng/L). Flash flood events associated with sewer overflows and soil mobilisation, which are expected to increase under climate change scenarios, should be considered when assessing the risks posed by pharmaceuticals to vulnerable aquatic ecosystems in the coastal areas.

A holistic assessment of the sources, prevalence, and distribution of bisphenol A and analogues in water, sediments, biota and plastic litter of the Ebro Delta (Spain).

Bisphenol A (BPA) is one of the main ubiquitous compounds released from plastics in the environment. This compound, considered an endocrine disruptor, poses a risk to aquatic wildlife and human population, being included in multiple environmental monitoring programmes. Following the regulations restricting BPA use in the last years, BPA-like chemicals have been produced and used as BPA substitutes. However, they are not commonly included in monitoring programs yet and their presence is thus misrepresented, despite showing similar endocrine disrupting potential. In this work, an analytical method for analysing bisphenol A and five of its analogues (Bisphenol S, B, F, AF and Tetrabromobisphenol A) is described, validated for water (riverine, sea and wastewater), sediment, and biota (fish and biofilm) and applied to monitor their presence in the Ebro River Delta (NE Spain). In addition, plastic litter was also collected to evaluate their role as potential source of bisphenols. All compounds except BPF were detected in the analysed samples. Wastewater treatment plants (WWTPs) were discarded as major sources of BPs into the natural aquatic environment, as no BPs were detected in treated effluents. Indeed, the high levels of BPs in the natural environment could be related with direct discharge of raw wastewater from small rural population nucleus. The analysis of riverine plastic leachates yielded 4 out of the 6 BPs analysed, strengthening the hypothesis that plastic debris are also a source of BPs in the natural environment. Whereas Bisphenol S and BPA were detected in water and, to a limited extent, in biota, less polar analogues (mainly BPAF and TBBPA) were not found in any of the water samples. Instead, these hydrophobic BPs were found in fish tissues and biofilm, pointing out plastics and microplastics as their possible vectors. Finally, biofilm demonstrated its potential as sentinel of chemical contamination in freshwater environment.

Occurrence and accumulation of pharmaceutical products in water and biota of urban lowland rivers.

We evaluated the distribution of eleven groups of pharmaceutically active compounds (PhACs) in surface waters and biota of different trophic levels, in five sites of two lowland urban rivers in Argentine. Twenty-nine out of 39 PhACs and two metabolites were detected in at least one water sample (2-9622 ng/L), eleven detected in biofilms (1-179 ng/g d.w.) and eight in the macrophyte Lemna gibba (4-112 ng/g d.w). The two more polluted sites had a similar distribution of the main groups of compounds. In surface waters, the largest concentrations were for the analgesic acetaminophen (9622 ng/L), the antibiotic sulfamethoxazole (326 ng/L), the antihypertensive valsartan (963 ng/L), the ß-blocking agent atenolol (427 ng/L), the diuretic hydrochlorothiazide (445 ng/L) and the psychiatric drug carbamazepine (99 ng/L). The antibiotic ciprofloxacin exhibited the highest concentration in the biofilm (179 ng/g d.w.) and in the macrophyte L. gibba (112 ng/g d.w.) Several compounds were detected in the water but not in the biota (e.g., codeine and bezafibrate), and others (e.g., azithromycin and citalopram) were found in the biota but not in the surface water. Significant bioaccumulation factors (>1000 L/kg d.w.) were obtained for venlafaxine and ciprofloxacin in biofilm. Our results show that PhACs may accumulate in several biological compartments. Within an environmental compartment, similar PhACs profile and concentrations were found in different sites receiving urban pollution. Among different compartments, biofilms may be the most suitable biota matrix to monitor the immediate reception of PhACs in the biota. Our results indicate that the presence of PhACs in urban rivers and their accumulation in the biota could be incorporated as symptoms of the urban stream syndrome.

Unravelling the performance of UV/H2O2 on the removal of pharmaceuticals in real industrial, hospital, grey and urban wastewaters.

This study provides an integrated assessment of UV/H2O2 treatment of different real wastewater matrices: two urban wastewater treatment plants (WWTPs) secondary effluents, greywater, hospital, and pharmaceutical industrial effluents. It considers micropollutant removal (up to 30 pharmaceuticals and 13 transformation products at environmental concentrations), energy efficiency and effluent toxicity. The complexity of the wastewater matrix negatively affected the UV fluence in the photo-reactor, scavenged hydroxyl radicals and hindered a proper H2O2 utilization thus reducing the treatment efficiency. At the optimal treatment conditions, overall pharmaceuticals removal was the highest for urban WWTPs effluents (69%-86%), followed by greywater (59%), hospital (36%) and industrial (17%) effluents. The ecotoxicity of the treated samples was reduced around one toxicity unit after the UV/H2O2 treatment in all cases except in industrial wastewater. The average observed removal in urban wastewater effluents and greywater for photo-susceptible, moderately photo-susceptible, and most photo-resistant compounds was 93%, 73% and 46% including outliers, respectively. The calculated electrical energy per order (EEO) values were 0.9-1.5 kWh/(m3·order) for urban WWTP effluents and greywater while for hospital and industrial effluents was much higher (7.3-9.1 kWh/(m3·order)).

A protocol for wide-scope non-target analysis of contaminants in small amounts of biota using bead beating tissuelyser extraction and LC-HRMS.

This work describes a robust and powerful method for wide-scope target and non-target analysis of xenobiotics in biota samples based on bead beating tissuelyser extraction, solid phase extraction (SPE) clean-up and further detection by liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS). Unlike target methodologies, non-target methods usually aim at determining a wide range of still unknown substances with different physicochemical properties. Therefore, losses during the extraction process were minimised. Apart from that, the reduction of possible interferences showed to be necessary to expand the number of compounds that can be detected. This was achieved with an additional SPE clean-up step carried out with mixed-bed multi-layered cartridges. The method was validated with a set of 27 compounds covering a wide range of physicochemical properties, and further applied to the analysis of krill and fish samples.•The bead beating extraction was efficient for a wide range of organic pollutants in small quantities of biota samples.•Multi-layered solid phase extraction clean-up yield a wide xenobiotics coverage reducing matrix effects.•Method validation with 27 compounds led to a suitable method for non-target analysis of organic pollutants in biota.

Showcasing the potential of wastewater-based epidemiology to track pharmaceuticals consumption in cities: Comparison against prescription data collected at fine spatial resolution.

While the extent of pharmaceutical consumption within a society/community is of high relevance to its health, economy and general wellbeing, this data is often not readily available. Herein, we strengthen a wastewater-based epidemiology (WBE) approach as a way to track the consumption of pharmaceuticals within the sampled community. This method is less laborious than established questionnaire or databases approaches and allows a higher temporal and spatial resolution. The WBE approach was conducted by sampling influent wastewater from two wastewater treatment plants of different size. A total of 39 targeted compounds were quantified by liquid chromatography coupled with tandem mass spectrometry. The number of prescriptions and the defined daily doses for each prescription was obtained from the reference database of The Catalan Health System to validate the wastewater-based approach. The wastewater sampling and the data inquiry were both executed during the same period (October 2019) and standardised for comparison to treatments per 1,000 inhabitants per day. The back-calculation parameters were improved from previous studies by including the faecal excretion rate of the pharmaceuticals. For prescription only pharmaceuticals, where prescription numbers are expected to be a good estimate of consumption, our WBE approach agreed with 27 out of 32 (<0.7 order of magnitude). Common over-the-counter pharmaceuticals such as acetaminophen, ibuprofen and naproxen showed much higher values for treatments per day per 1,000 inhabitant in wastewater than prescribed, reflecting the usefulness of WBE in obtaining an estimate of the total consumption i.e. with and without a prescription.

Diet quality and NSAIDs promote changes in formation of prostaglandins by an aquatic invertebrate.

We used the freshwater insect Hydropsyche sp. to investigate the impact of diets lacking arachidonic acid (ARA) and an environmentally relevant mixture of NSAIDs (Ibuprofen, Ketoprofen, Diclofenac and Naproxen at a nominal concentration of all compounds together 16.75 µg L-1) on their metabolism of ARA and prostaglandins (PGs). The organisms were exposed for 16 days to four different treatments: a reference (FF), a diet lacking ARA (O), to NSAIDs in water (FFN) and to the combination of the two factors (ON). Mortality, biomass and bioconcentration of pharmaceuticals were investigated. The ARA and PGs levels in the organisms were monitored by utilising a targeted metabolomics approach. NSAIDs or dietary constraints did not produce significant differences in biomass or mortality of Hydropsyche sp. among treatments. In organisms exposed to NSAIDs, all pharmaceuticals were detected, except for Ketoprofen. Metabolomic approach determined the presence of PGH2, PGE1 and PGD1. Levels of ARA diminished significantly in those organisms in treatment ON. The levels of PGs responded negatively to the absence of ARA in diet: PGH2 diminished significantly with respect to the reference in treatment O while PGE1 diminished significantly in treatment ON. Regarding the effects of NSAIDs on ARA metabolism, our results suggest that it was sensitive to NSAIDs, but effects were weak and did not imply a general decrease in the PGs. We confirmed that ARA was the main substrate for the synthesis of PGs in Hydropsyche sp, their absence or poor levels of ARA in diet, produced changes in the PG levels.

Exposure to single and binary mixtures of fullerenes and triclosan: Reproductive and behavioral effects in the freshwater snail Radix balthica.

Emerging pollutants occur in complex mixtures in rivers and have the potential to interact with freshwater organisms. The chronic effects of nominal exposure to 3 µg/L of fullerenes (C60) and 1 µg/L of triclosan (TCS) alone and in a binary mixture, were evaluated using the freshwater snail Radix balthica. Pollutants accumulation, reproductive output and feeding behavior were selected as sublethal endpoints. After 21 days of exposure, we did not observe interactive effects between TCS and C60 on the studied endpoints, except for the accumulation of C60 in R. balthica in TCS + C60 treatment, which was lower than when the fullerenes were alone. Neither TCS nor C60 caused significant effects on reproduction, expressed as number of eggs per individual, but an increase in the clutch size was observed in treatments with TCS at the third week of exposure, independently of the presence of C60 (16.15 ± 1.67 and 18.9 ± 4.01 eggs/egg mass in TCS and TCS + C60 treatments, respectively, vs. 13.17 ±â€¯4.01 in control). The presence of C60 significantly enhanced the grazing activity of R. balthica during the first seven days (4.95 ±â€¯1.35 and 3.91 ±â€¯0.59% of the area grazed per individual in C60 and TCS + C60 treatments, respectively, vs 2.6 ±â€¯0.39% in control). The accumulation of TCS was quite similar in treatments where this pollutant was present (BAF ≈ 1007 L/kg d.w.); however, the accumulation of C60 was higher when the nanoparticles were alone (BAF = 254.88 L/kg d.w.) than when it was in the binary mixture (BAF = 7.79 L/kg d.w). Overall, although TCS has been listed as an endocrine disrupter compound, no significant effects on reproduction were observed in the assayed conditions. Regarding C60, the limited effects on feeding activity and the low BAF obtained in this experiment indicate that fullerenes do not have ecological consequences of relevance at the studied environmental concentrations in freshwater snails.

Human pharmaceuticals in three major fish species from the Uruguay River (South America) with different feeding habits.

The accumulation of 17 human pharmaceuticals (HPs) was investigated in the muscle of three fish species characteristic of the "Rio de la Plata Basin" with different feeding habits and of relevance for human consumption: Megaleporinus obtusidens, Salminus brasiliensis, and Prochilodus lineatus. Fish were sampled in fall and spring from 8 localities distributed along 500 Km of the Uruguay River. Atenolol and carbamazepine were the most frequently detected HPs (>50%), but at concentrations always below 1 µg/kg wet weight (w/w). Hydrochlorothiazide, metoprolol, venlafaxine, propranolol, codeine, and the carbamazepine metabolite, 2-hydroxycarbamazepine, were accumulated at higher levels showing maximum concentrations between 1 and 10 µg/kg (w/w), but infrequently (<50%). The other HPs were always below 1 µg/kg (w/w) and at frequencies lower than 50%. Distinctive accumulation patterns were observed among species at different trophic levels. However, biomagnification trends were not identified for any compound. The highest number and concentration of HPs were found in M. obtusidens (omnivorous), followed by P. lineatus (detritivorous), and lastly S. brasiliensis (piscivorous). The most recurrent HPs (i.e. carbamazepine and atenolol) were present in all species, but others exclusively in one. Geographical variations were only found for carbamazepine and atenolol in M. obtusidens and P. lineatus, showing higher concentrations in localities closer to the Rio de la Plata estuary. Differences in the HPs concentrations among seasons were not identified. Acceptable daily intake and predicted no effect concentrations would indicate that measured muscle concentrations in fish from the Uruguay River do not pose a serious risk for human consumption nowadays. Further studies will be necessary for assessing the potential adverse effects on studied fish species.

Contaminants of emerging concern in freshwater fish from four Spanish Rivers.

This study investigated the occurrence of 135 contaminants of emerging concern (CECs) - pharmaceuticals, pesticides, a set of endocrine disrupting compounds (EDCs) (parabens, bisphenols, hormones, triazoles, organophosphorus flame retardants and triclosan), UV-filters, perfluoroalkyl substances (PFASs) and halogenated flame retardants (HFRs) - in 59 fish samples, collected in 2010 in 4 Spanish Rivers (Guadalquivir, Júcar, Ebro and Llobregat). Of the 135 CECs, 76 including 8 pharmaceuticals, 25 pesticides, 10 EDCs, 5 UV-filters, 15 PFASs and 13 HFRs were detected. Pharmaceuticals were the less frequently found and at lower concentrations. Pesticides, EDCs, UV-filters, PFASs and HFRs were detected more frequently (>50% of the samples). The maximum concentrations were 15 ng/g dry weight (dw) for pharmaceuticals (diclofenac), 840 ng/g dw for pesticides (chlorpyrifos), 224 ng/g dw for EDCs (bisphenol A), 242 ng/g dw for UV-filters (EHMC), 1738 ng/g dw for PFASs (PFHxA) and 64 ng/g dw for HFRs (Dec 602). The contaminants detected in fish are commonly detected also in sediments. In light of current knowledge, the risk assessment revealed that there was no risk for humans related to the exposure to CECs via freshwater fish consumption. However, results provide detailed information on the mixtures of CECs accumulated that would be very useful to identify their effects on aquatic biota.

The role of sorption processes in the removal of pharmaceuticals by fungal treatment of wastewater.

The contribution of the sorption processes in the elimination of pharmaceuticals (PhACs) during the fungal treatment of wastewater has been evaluated in this work. The sorption of four PhACs (carbamazepine, diclofenac, iopromide and venlafaxine) by 6 different fungi was first evaluated in batch experiments. Concentrations of PhACs in both liquid and solid (biomass) matrices from the fungal treatment were measured. Contribution of the sorption to the total removal of pollutants ranged between 3% and 13% in relation to the initial amount. The sorption of 47 PhACs in fungi was also evaluated in a fungal treatment performed in 26days in a continuous bioreactor treating wastewater from a veterinary hospital. PhACs levels measured in the fungal biomass were similar to those detected in conventional wastewater treatment (WWTP) sludge. This may suggest the necessity of manage fungal biomass as waste in the same manner that the WWTP sludge is managed.

Pharmaceuticals removal and microbial community assessment in a continuous fungal treatment of non-sterile real hospital wastewater after a coagulation-flocculation pretreatment.

Hospital wastewaters are a main source of pharmaceutical active compounds, which are usually highly recalcitrant and can accumulate in surface and groundwater bodies. Fungal treatments can remove these contaminants prior to discharge, but real wastewater poses a problem to fungal survival due to bacterial competition. This study successfully treated real non-spiked, non-sterile wastewater in a continuous fungal fluidized bed bioreactor coupled to a coagulation-flocculation pretreatment for 56 days. A control bioreactor without the fungus was also operated and the results were compared. A denaturing gradient gel electrophoresis (DGGE) and sequencing approach was used to study the microbial community arisen in both reactors and as a result some bacterial degraders are proposed. The fungal operation successfully removed analgesics and anti-inflammatories, and even the most recalcitrant pharmaceutical families such as antibiotics and psychiatric drugs.

Removal of pharmaceuticals from wastewater by fungal treatment and reduction of hazard quotients.

The elimination of 81 pharmaceuticals (PhACs) by means of a biological treatment based on the fungus Trametes versicolor was evaluated in this work. PhAC removal studied in different types of wastewaters (urban, reverse osmosis concentrate, hospital, and veterinary hospital wastewaters) were reviewed and compared with conventional activated sludge (CAS) treatment. In addition, hazard indexes were calculated based on the exposure levels and ecotoxicity for each compound and used for the evaluation of the contaminants removal. PhAC elimination achieved with the fungal treatment (mean value 76%) was similar or slightly worse than the elimination achieved in the CAS treatment (85%). However, the fungal reactor was superior in removing more hazardous compounds (antibiotics and psychiatric drugs) than the conventional activated sludge in terms of environmental risk reduction (93% and 53% of reduction respectively). Fungal treatment can thus be considered as a good alternative to conventional treatment technologies for the elimination of PhACs from wastewaters.

Generation of synthetic influent data to perform (micro)pollutant wastewater treatment modelling studies.

The use of process models to simulate the fate of micropollutants in wastewater treatment plants is constantly growing. However, due to the high workload and cost of measuring campaigns, many simulation studies lack sufficiently long time series representing realistic wastewater influent dynamics. In this paper, the feasibility of the Benchmark Simulation Model No. 2 (BSM2) influent generator is tested to create realistic dynamic influent (micro)pollutant disturbance scenarios. The presented set of models is adjusted to describe the occurrence of three pharmaceutical compounds and one of each of its metabolites with samples taken every 2-4h: the anti-inflammatory drug ibuprofen (IBU), the antibiotic sulfamethoxazole (SMX) and the psychoactive carbamazepine (CMZ). Information about type of excretion and total consumption rates forms the basis for creating the data-defined profiles used to generate the dynamic time series. In addition, the traditional influent characteristics such as flow rate, ammonium, particulate chemical oxygen demand and temperature are also modelled using the same framework with high frequency data. The calibration is performed semi-automatically with two different methods depending on data availability. The 'traditional' variables are calibrated with the Bootstrap method while the pharmaceutical loads are estimated with a least squares approach. The simulation results demonstrate that the BSM2 influent generator can describe the dynamics of both traditional variables and pharmaceuticals. Lastly, the study is complemented with: 1) the generation of longer time series for IBU following the same catchment principles; 2) the study of the impact of in-sewer SMX biotransformation when estimating the average daily load; and, 3) a critical discussion of the results, and the future opportunities of the presented approach balancing model structure/calibration procedure complexity versus predictive capabilities.

Attenuation of pharmaceuticals and their transformation products in a wastewater treatment plant and its receiving river ecosystem.

Pharmaceuticals are designed to improve human and animal health, but may also be a threat to freshwater ecosystems, particularly after receiving urban or wastewater treatment plant (WWTP) effluents. Knowledge on the fate and attenuation of pharmaceuticals in engineered and natural ecosystems is rather fragmented, and comparable methods are needed to facilitate the comprehension of those processes amongst systems. In this study the dynamics of 8 pharmaceuticals (acetaminophen, sulfapyridine, sulfamethoxazole, carbamazepine, venlafaxine, ibuprofen, diclofenac, diazepam) and 11 of their transformation products were investigated in a WWTP and the associated receiving river ecosystem. During 3 days, concentrations of these compounds were quantified at the influents, effluents, and wastage of the WWTP, and at different distances downstream the effluent at the river. Attenuation (net balance between removal and release from and to the water column) was estimated in both engineered and natural systems using a comparable model-based approach by considering different uncertainty sources (e.g. chemical analysis, sampling, and flow measurements). Results showed that pharmaceuticals load reduction was higher in the WWTP, but attenuation efficiencies (as half-life times) were higher in the river. In particular, the load of only 5 out of the 19 pharmaceuticals was reduced by more than 90% at the WWTP, while the rest were only partially or non-attenuated (or released) and discharged into the receiving river. At the river, only the load of ibuprofen was reduced by more than 50% (out of the 6 parent compounds present in the river), while partial and non-attenuation (or release) was observed for some of their transformation products. Linkages in the routing of some pharmaceuticals (venlafaxine, carbamazepine, ibuprofen and diclofenac) and their corresponding transformation products were also identified at both WWTP and river. Finally, the followed procedure showed that dynamic attenuation in the coupled WWTP-river system could be successfully predicted with simple first order attenuation kinetics for most modeled compounds.