Determination of pharmaceutical residues in wastewater using high performance liquid chromatography coupled to quadrupole-Orbitrap mass spectrometry

Monitoring Pharmaceuticals and Personal Care Products in Healthcare Effluent Wastewater Samples and the Effectiveness of Drug Removal in Wastewater Treatment Plants Using the UHPLC-MS/MS Method

A multi-residue UHPLC-MS/MS analytical method, previously developed for monitoring 52 pharmaceuticals in drinking water, was used to analyse these pharmaceuticals in wastewater originating from healthcare facilities in the Czech Republic. Furthermore, the methodology was expanded to include the evaluation of the effectiveness of drug removal in Czech wastewater treatment plants (WWTPs). Of the 18 wastewater samples analysed by the validated UHPLC-MS/MS, each sample contained at least one quantifiable analyte. This study reveals the prevalence of several different drugs; mean concentrations of 702 μg L-1 of iomeprol, 48.8 μg L-1 of iopromide, 29.9 μg L-1 of gabapentin, 42.0 μg L-1 of caffeine and 82.5 μg L-1 of paracetamol were present. An analysis of 20 samples from ten WWTPs revealed different removal efficiencies for different analytes. Paracetamol was present in the inflow samples of all ten WWTPs and its removal efficiency was 100%. Analytes such as caffeine, ketoprofen, naproxen or atenolol showed high removal efficiencies exceeding 80%. On the other hand, pharmaceuticals like furosemide, metoprolol, iomeprol, zolpidem and tramadol showed lower removal efficiencies. Four pharmaceuticals exhibited higher concentrations in WWTP effluents than in the influents, resulting in negative removal efficiencies: warfarin at -9.5%, indomethacin at -53%, trimethoprim at -54% and metronidazole at -110%. These comprehensive findings contribute valuable insights to the pharmaceutical landscape of wastewater from healthcare facilities and the varied removal efficiencies of Czech WWTPs, which together with the already published literature, gives a more complete picture of the burden on the aquatic environment.

Non-steroidal anti-inflammatory drugs (NSAIDs) in the environment: Updates on pretreatment and determination methods

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used in human and animal health care to reduce persistent inflammation, pain and fever because of their anti-inflammatory, analgesic and antipyretic effects. However, the improper discharge and disposal make it becomes a major contaminant in the environment, which poses a big threat to the ecosystem. For this reason, accurate, sensitive, effective, green, and economic techniques are urgently required and have been rapidly developed in recent years. This review summarizes the advancement of sample preparation technologies for NSAIDs involving solid-phase extraction, solid-phase microextraction, liquid-phase microextraction, QuEChERS, and matrix solid-phase dispersion. Meanwhile, we overview and compare analytical technologies for NSAIDs, including liquid chromatography-based methods, gas chromatography-based methods, capillary electrophoresis, and sensors, particularly the development of liquid chromatography-based methods. Furthermore, we focus on their progress and conduct a comparison between their advantages and disadvantages.

Efficient Validation Strategies in Environmental Analytical Chemistry: A Focus on Organic Micropollutants in Water Samples

This article critically reviews analytical method validation and quality control applied to the environmental chemistry field. The review focuses on the determination of organic micropollutants (OMPs), specifically emerging contaminants and pesticides, in the aquatic environment. The analytical technique considered is (gas and liquid) chromatography coupled to mass spectrometry (MS), including high-resolution MS for wide-scope screening purposes. An analysis of current research practices outlined in the literature has been performed, and key issues and analytical challenges are identified and critically discussed. It is worth emphasizing the lack of specific guidelines applied to environmental analytical chemistry and the minimal regulation of OMPs in waters, which greatly affect method development and performance, requirements for method validation, and the subsequent application to samples. Finally, a proposal is made for method validation and data reporting, which can be understood as starting points for further discussion with specialists in environmental analytical chemistry.

Wastewater surveillance of 105 pharmaceutical drugs and metabolites by means of ultra-high-performance liquid-chromatography-tandem high resolution mass spectrometry

Water pollution from pharmaceutical drugs is becoming an environmental issue of increasing concern, making water quality monitoring a crucial priority to safeguard public health. In particular, the presence of antidepressants, benzodiazepines, antiepileptics, and antipsychotics require specific attention as they are known to be harmful to aquatic biota. In this study, a multi-class comprehensive method for the detection of 105 pharmaceutical residues in small (30 mL) water samples was developed according to fit-for-purpose criteria and then applied to provide wide screening of samples obtained from four Wastewater Treatment Plants (WWTPs) in northern Italy. The filtered samples (0.22 µm filters) were extracted by SPE, and then eluted. 5 µL of the concentrated samples were analyzed by a UHPLC-QTOF-HRMS method validated for screening purposes. Adequate sensitivity was recorded for all target analytes, with limits of detection below 5 ng/L for 76 out of 105 analytes. A total of 23 out of the 105 targeted pharmaceutical drugs was detected in all samples. Several further compounds were detected over wide concentration intervals, ranging from ng/L to µg/L. In addition, the retrospective analysis of full-scan QTOF-HRMS data was exploited to carry out an untargeted screening of some drugs' metabolites. As a proof of concept, it was investigated the presence of the carbamazepine metabolites, which is among the most frequently detected contaminants of emerging concern in wastewater. Thanks to this approach, 10,11-dihydro-10-hydroxycarbamazepine, 10,11-dihydro-10,11-dihydroxycarbamazepine and carbamazepine-10,11-epoxide were identified, the latter requiring particular attention, since it exhibits antiepileptic properties similar to carbamazepine and potential neurotoxic effects in living organism.

Preparation of a single and reusable biopolymer-based film for the extraction and preconcentration of anti-inflammatory drugs from environmental water samples

One of the main goals of green chemistry is to reduce the use of toxic materials and the generation of hazardous waste, both during method development and in the synthesis of the materials used. Thus, a biodegradable, single and reusable material composed of agarose and multi-walled carbon nanotubes was proposed. The film preparation was carefully optimized in order to obtain a one-piece sorbent, with high extraction efficiency and the possibility of reuse. The film was tested in the simultaneous extraction and preconcentration of three non-steroidal anti-inflammatory drugs (ketorolac, ketoprofen and piroxicam) from environmental water samples. The optimal extraction parameters were as follows: isopropyl alcohol as the activation solvent, a sample pH value of 3.0, extraction time of 30 min, 2.00 mL of acetonitrile as the eluent, an elution time of 5 minutes, and a sample volume of 250.00 mL. Under these conditions, the film was reusable 50 times without losing its extraction capacity significantly. HPLC with a photodiode array detector was used for the separation and determination. The method presented a linear range between 0.10 and 1.2 μg L^-1, good sensitivity with limits of detection between 0.0075 and 0.0089 μg L^-1, and quantification between 0.025 and 0.030 μg L^-1. In addition, low RSD values (0.46-3.13%) were obtained demonstrating satisfactory precision. Stream water samples were analyzed, and recoveries between 82.0 and 109.0% were obtained.

Erythromycin Scavenging from Aqueous Solutions by Zeolitic Materials Derived from Fly Ash

Erythromycin (EA) is an antibiotic whose concentration in water and wastewater has been reported to be above the standard levels. Since the methods used so far to remove EA from aquatic environments have not been effective, the development of effective methods for EA removal is necessary. In the present study, fly ash (FA)-based zeolite materials, which have not been investigated as EA sorbents before, were used. The possibilities of managing waste FA and using its transformation products for EA sorption were presented. The efficiency of EA removal from experimental solutions and real wastewater was evaluated. In addition, the sorbents' mineral composition, chemical composition, and physicochemical properties and the effects of adsorbent mass, contact time, initial EA concentration, and pH on EA removal were analyzed. The EA was removed within the first 2 min of the reaction with an efficiency of 99% from experimental solutions and 94% from real wastewater. The maximum adsorption capacities were 314.7 mg g^-1 for the fly ash-based synthetic zeolite (NaP1_FA) and 363.0 mg g^-1 for the carbon-zeolite composite (NaP1_C). A fivefold regeneration of the NaP1_FA and NaP1_C showed no significant loss of adsorption efficiency. These findings indicate that zeolitic materials effectively remove EA and can be further investigated for removing other pharmaceuticals from water and wastewater.

The use of non-target high-resolution mass spectrometry screening to detect the presence of antibiotic residues in urban streams of Greensboro North Carolina

Antibiotic pollution in aquatic systems is a concern for human and environmental health. The concern is largely due to the global occurrence of antibiotic-resistant bacteria. From 2017 to 2018 in the NC Piedmont, 15 ion masses associated with antibiotics were detected in rural streams and groundwater. Four of these masses were confirmed to be antibiotics through target analysis (sulfamethoxazole, sulfamerazine, erythromycin, danofloxacin). Concentrations of antibiotics were as high as 1.8 μg/L. As a follow-up, antibiotic residues in urban streams sites in Greensboro, NC, USA, were investigated. Urban streams are heavily influenced by the dense populations surrounding them. In the fall, winter, and spring seasons, surface water was collected from eight sites along two urban streams. Sampling was conducted at streams sites above and below municipal hospitals and wastewater treatment facilities in the study area. At the conclusion of the survey, nine ion masses associated with antibiotics used in both human and veterinary medicine were detected from surface water collected. Three of the four antibiotics targeted in rural stream samples were detected and confirmed in urban stream samples (sulfamerazine, danofloxacin, and erythromycin). Detection frequencies of the three antibiotics ranged from 0 to 46%. Concentrations of each target antibiotic was as followed: SMX (0 to <10 ng/L), SMR (0 to <11 ng/L), DAN (0 to <20 ng/L), and ETM (0 to <15 ng/L). Each target antibiotic concentration was below our methods quantification limits. Our risk assessment analysis showed that the target antibiotics posed no risk to fish, daphnia, and green algae within this region of NC (RQ < 0.1). Compared to rural streams in this region of NC, antibiotic pollution is less prevalent in urban streams. The differences between urban and rural streams may be driven by the varying land use and suggest more research should be dedicated to monitoring these contaminants in rural areas of the United States.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s40201-021-00688-9.

Removal of cephalexin and erythromycin antibiotics, and their resistance genes, by microalgae-bacteria consortium from wastewater treatment plant secondary effluents

Antibiotics have become a concern in the aquatic environments owing to the potential development of bacterial resistances. Thus, this study evaluated the removal of cephalexin (CEP) and erythromycin (ERY) from a local wastewater treatment plant (WWTP) effluent, mediated by microalgae-bacteria consortium. Likewise, the removal of correlated antibiotics resistance genes bla_TEM and ermB was also assessed. The incubation results showed that the added concentrations of selected antibiotics did not restrain the consortium growth. Moreover, CEP and ERY were almost completely removed after the cultivation period, reaching total removals of 96.54% and 92.38%, respectively. The symbiotic interaction between microalgae and bacteria plays a role in the kinetics removal of CEP and ERY. The abundance of bla_TEM and ermB was reduced by 0.56 and 1.75 logs, respectively. Lastly, our results suggest that technology based on natural microalgae-bacteria consortium could be a potential alternative to improve the quality of WWTP effluents.

Vortex-Assisted Dispersive Molecularly Imprinted Polymer-Based Solid Phase Extraction of Acetaminophen from Water Samples Prior to HPLC-DAD Determination

In the present study, acetaminophen (ACT) molecularly imprinted polymer (ACT-MIP) were successfully synthesized via surface imprinting polymerization. The structural and morphological properties of ACT-MIP were characterized using various analytical techniques. ACT-MIP were used as an adsorbent in a vortex-assisted dispersive molecularly imprinted solid-phase micro-extraction (VA-d-μ-MISPE), coupled with a high-performance liquid chromatography–diode array detector (HPLC-DAD) method for the determination of ACT in water samples. Influential parameters such as the mass of adsorbent, vortex speed, extraction time, desorption volume, and desorption time were optimized using a multivariate approach. Under optimum conditions, the maximum binding capacities of ACT-MIP and NIP (non-imprinted polymers) were 191 mg/g and 71.5 mg/g, respectively. The linearity was attained across concentrations ranging from 0.630 to 500 µg/L, with a coefficient of determination of 0.9959. For ACT-MIP, the limit of detection (LOD) and limit of quantification (LOQ), enhancement factor, and precision of the method were 0.19 ng/L, 0.63 ng/L, 79, and <5%, respectively. The method was applied in the analysis of spiked water samples, and satisfactory percentage recoveries in the range of 95.3–99.8% were obtained.

Two-dimensional liquid chromatography - mass spectrometry as an effective tool for assessing a wide range of pharmaceuticals and biomarkers in wastewater-based epidemiology studies

The biomarkers used in wastewater-based epidemiology studies have a wide range of physicochemical properties, making simultaneous analysis extremely challenging or even impossible. So far, the majority of analytical procedures employed in this field have focused on specific classes or a limited number of analytes. The heart-cutting two-dimensional liquid chromatography tandem mass spectrometry technique (2D-LC-MS/MS) has enabled the incorporation of compounds with significantly different polarities in a single analytical method. In this study, a 2D-LC-MS/MS method has been developed and optimized for the simultaneous analysis of various biomarkers in wastewater, providing relevant information about lifestyle habits (the usage of alcohol, tobacco, and caffeine), health and well-being (pharmaceuticals), and a population size biomarker (5-HIAA) that is useful for correct calculation of human population during wastewater-based epidemiology studies. A single-laboratory validation procedure showed satisfactory analytical performance, with the mean trueness for most compounds falling in the range of 80÷110 % and the mean repeatability being less than 20 %. The applicability of the method was evaluated by testing 28 wastewater samples collected at different wastewater treatment plants in Latvia. The obtained results revealed the occurrence of 44 out of 62 selected biomarkers, with the lowest quantified concentration at 1.1 ng L^-1 in the case of xylometazoline and up to 148 μg L^-1 in the case of metformin and 156 μg L^-1 for caffeine.

Development of a multiclass method to quantify phthalates, pharmaceuticals, and personal care products in river water using ultra-high performance liquid chromatography coupled with quadrupole hybrid Orbitrap mass spectrometry

RATIONALE

The organic micropollutants such as phthalates, pharmaceuticals, and personal care products (PPPCPs) enter the surface water through various routes. The aim of this study is to develop a sensitive and efficient method to identify and quantify 26 PPPCPs found in river water with acceptable accuracy and precision using a liquid chromatograph hyphenated with quadrupole hybrid Orbitrap mass spectrometry (Q-Orbitrap-MS) in a single chromatographic run.

METHOD

The organic micropollutants were extracted from river water by solid-phase extraction (SPE) using hydrophilic-lipophilic balance sorbent and analyzed using an ultra-high performance liquid chromatograph (UHPLC) equipped with C18 stationary phase for chromatographic separation. The targeted mass experiments were conducted in a Q-Orbitrap-MS system in positive and negative electrospray ionization mode.

RESULTS

The method was found to be linear in the concentration range of 1-125 ng/L with coefficient of determination lying in the range of 0.995-0.999. The method achieved limit of quantification in the range of 0.41-1.72 ng/L, and method recovery measured at three different concentrations was found to be in the range of 75-115%. Intra- and interday precision expressed as percent relative standard deviation was found to be <15%. Matrix effect was found to be in the range of 83.5-109.79%. The matrix match calibration was used for quantification of PPPCPs in river water sample. The method performance was evaluated by analyzing real samples collected from Ganga River, and the concentrations of 21 analytes were found to be in the range of 0.76-9.49 ng/L for pharmaceuticals, 1.49-8.67 ng/L for phthalates, and 0.9-7.58 ng/L for personal care products.

CONCLUSIONS

The present method was found to be precise, sensitive, and rapid to determine 26 PPPCPs including phthalates in river water samples using SPE-UHPLC-Q-Orbitrap-MS.

Dangerous connections: biochemical and behavioral traits in Daphnia magna and Daphnia longispina exposed to ecologically relevant amounts of paracetamol

Exposure of nontarget organisms to therapeutic agents can cause distinct toxic effects, even at low concentrations. Paracetamol is a painkiller drug, widely used in human and veterinary therapies, being frequently found in the aquatic compartment in considerable amounts. Its toxicity has already been established for some species, but its full ecotoxicological potential is still not sufficiently described. To characterize the ecotoxicity of paracetamol, the present study evaluated several parameters, such as acute immobilization (EC₅₀ calculation), biochemical alterations, and behavioral effects, in two species of freshwater microcrustaceans of the genus Daphnia (D. magna and D. longispina). To increase the relevance of the data obtained, animals were exposed to levels of paracetamol similar to those already reported to occur in the wild. Data showed antioxidant responses in both species, namely an increase of catalase and GSTs activities in D. magna. On the contrary, effects of paracetamol on D. longispina included only an impairment of GSTs activity. Despite the absence of anticholinesterasic effects, behavioral modifications were also observed. This set of data indicates that realistic levels of paracetamol may trigger the activation of the antioxidant defense system of freshwater crustaceans, causing changes in behavioral traits (increase in swimming time, but with a reduction in swimming distance) of unknown etiology that are likely to affect normal life traits of wild populations.

High-throughput quantification of eighteen heterocyclic aromatic amines in roasted and pan-fried meat on the basis of high performance liquid chromatography-quadrupole-orbitrap high resolution mass spectrometry

Triple quadrupole mass spectrometry has been the main technique for HAAs analysis in recent decade, while it requires extensive optimization of compound-dependent parameters. A novel method based on HPLC-Q-Orbitrap-HRMS was developed firstly for simultaneous determination of eighteen HAAs. Extraction and purification conditions were optimized and the developed method was validated in terms of linearity, accuracy and precision. Results indicated eighteen HAAs and two internal standards could be separated in 12 min using a gradient elution program. The full MS/dd-MS² scan was adopted for analysis, which indicated favorable recoveries (71.3-114.8%) along with LODs and LOQs in the ranges of 0.02-0.6 and 0.05-2.0 μg/kg, respectively. Internal standards used for calibration could effectively reduce quantification errors produced by matrix effects. The validated method was successfully applied for HAAs analysis in roasted and pan-fried meat and was confirmed to be an alternative method when triple quadrupole mass spectrometry is absent in lab.

Development of a maleic acid-based material to selectively solid-phase extract basic compounds from environmental samples

This study presents a novel mixed-mode weak cation-exchange (WCX) material. This material was prepared by means of the functionalization of a mesoporous divinylbenzene (DVB) resin with maleic acid (maleic acid-DVB), which yielded a high carboxylic moiety content resulting in WCX interactions as well as suitable specific surface area for reversed-phase interactions. After the optimization of the solid-phase extraction (SPE) protocol to enhance the selectivity of the sorbent, this material was evaluated as a novel WCX sorbent in the SPE of a group of drugs from environmental water samples. The method is based on SPE followed by liquid chromatography (LC) coupled to high resolution mass spectrometry (HRMS) with an Orbitrap analyzer, and was validated and applied for the determination of basic drugs in river, effluent and influent wastewater samples. Maleic acid-DVB sorbent yielded suitable recovery rates (57% to 89%) and an acceptable matrix effect (<32%) thanks to the effective washing step included when these environmental waters were loaded through the novel resin. The method was applied to different environmental water samples and some basic drugs were suitably quantified in these environmental samples.

Magnetic Mesoporous Carbon/β-Cyclodextrin-Chitosan Nanocomposite for Extraction and Preconcentration of Multi-Class Emerging Contaminant Residues in Environmental Samples

This study reports the development of magnetic solid-phase extraction combined with high-performance liquid chromatography for the determination of ten trace amounts of emerging contaminants (fluoroquinolone antibiotics, parabens, anticonvulsants and β-blockers) in water systems. Magnetic mesoporous carbon/β-cyclodextrin-chitosan (MMPC/Cyc-Chit) was used as an adsorbent in dispersive magnetic solid-phase extraction (DMSPE). The magnetic solid-phase extraction method was optimized using central composite design. Under the optimum conditions, the limits of detection (LODs) ranged from 0.1 to 0.7 ng L-1, 0.5 to 1.1 ng L-1 and 0.2 to 0.8 ng L-1 for anticonvulsants and β-blockers, fluoroquinolone and parabens, respectively. Relatively good dynamic linear ranges were obtained for all the investigated analytes. The repeatability (n = 7) and reproducibility (n = 5) were less than 5%, while the enrichment factors ranged between 90 and 150. The feasibility of the method in real samples was assessed by analysis of river water, tap water and wastewater samples. The recoveries for the investigated analytes in the real samples ranged from 93.5 to 98.8%, with %RSDs under 4%.

Exploring the phototransformation and assessing the in vitro and in silico toxicity of a mixture of pharmaceuticals susceptible to photolysis

The present study comprehensively investigates the phototransformation and ecotoxicity of a mixture of twelve pharmaceutically active compounds (PhACs) susceptible to photolysis. Namely, three antibiotics (ciprofloxacin, levofloxacin, moxifloxacin), three antidepressants (bupropion, duloxetine, olanzapine), three anti-inflammatory drugs (diclofenac, ketoprofen, nimesulide), two beta-blockers (propranolol, timolol) and the antihistamine ranitidine were treated under simulated solar irradiation in ultra-pure and river water. A total of 166 different transformation products (TPs) were identified by ultra-high performance liquid chromatography coupled with Orbitrap high resolution mass spectrometry (UHPLC-Orbitrap HRMS), revealing the formation of twelve novel TPs and forty-nine not previously described in photolytic studies. The kinetic profiles of the major TPs resulting from a series of chemical reactions involving hydroxylation, cleavage and oxidation, dehalogenation, decarboxylation, dealkylation and photo substitution have been investigated and the transformation pathways have been suggested. Additionally, an in vitro approach to the toxicity assessment of daphnids was contrasted with ecotoxicity data based on the Ecological Structure Activity Relationships (ECOSAR) software comprising the in silico tool to determine the adverse effects of the whole mixture of photolabile parent compounds and TPs. The results demonstrated that photolysis of the target mixture leads to a decrease of the observed toxicity.

Rapid determination of pharmaceuticals in wastewater by direct infusion HRMS using target and suspect screening analysis

A wide-scope screening of active pharmaceutical ingredients (APIs) and their transformation products (TPs) in wastewater can yield valuable insights and pinpoint emerging contaminants that have not been previously reported. Such information is relevant to investigate their occurrence and fate in various environmental compartments. In this study, we explored the applicability of direct infusion high resolution mass spectrometry (DI-HRMS) for comprehensive and rapid detection of APIs and their TPs in wastewater samples. The method was developed using a Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) system and incorporated both wide-scope suspect screening and semi-quantitative determination of selected analytes. The identification strategy was based on the following criteria: narrow accurate mass window (±1.25 ppm) for two most abundant full-MS signals, isotopic pattern fit and additional confirmation on the basis of MS² spectra at three fragmentation levels. The tentative identification of suspects and target compounds relied on an in-house database containing more than 500 different APIs and TPs. The measured fragment spectra were matched against experimental MS² patterns obtained from a publicly available spectral library (MassBank of North America) and in-silico generated fragmentation features (from the CFM-ID algorithm). In total, 79 suspects were identified and 24 target compounds were semi-quantified in 72 wastewater samples. The highest detection frequencies in treated wastewater effluents were observed for diclofenac, metoprolol and telmisartan, while hydroxydiclofenac, dextrorphan, and carbamazepine metabolites were the most frequently detected TPs. The obtained API profiles were in accordance with the national consumption statistics and the origin of wastewater samples. The developed method is suitable for rapid screening of APIs in wastewater and can be used as a complementary tool to characterize API emissions from wastewater treatment facilities and to identify problematic compounds that require more rigorous monitoring.

Eco-friendly multivariate curve resolution-alternating least squares and chromatographic quantifications of some veterinary drug residues in pharmaceutical industrial wastewater

Three eco-friendly and cost-effective analytical methods were developed and optimized for quantitative analysis of some veterinary drug residues in production wastewater samples. The studied drugs were ivermectin, rafoxanide and sulfadimidine. A solid-phase extraction procedure was employed using Bond Elut C18 cartridges, prior to analysis. The first method was a chemometric approach called multivariate curve resolution - alternating least squares (MCR-ALS). A calibration model was developed and several figures of merit (RMSEP, SEP, bias, RE%) were calculated. The second method was a thin layer chromatography followed by densitometric measurements at 245 nm. The separation was performed using silica gel 60 F254 plates and ethyl acetate : acetonitrile : toluene : ammonia (20 : 3 : 2 : 1, by volume) as a developing system. The third method was a high performance liquid chromatographic separation on HiQsil C18 HS column with UV detection at 245 nm. The mobile phase consisted of acetonitrile : methanol : water (60 : 25 : 15, by volume), with a flow rate of 1.5 mL min-1. The proposed methods were validated according to ICH guidelines. The described procedures were applied to quantify the studied drug residues in synthetic and real industrial wastewater samples. The proposed methods were statistically compared with the official and the reported methods, showing no significant difference with respect to accuracy and precision at P = 0.05.

Paracetamol Sensing with a Pencil Lead Electrode Modified with Carbon Nanotubes and Polyvinylpyrrolidone

The determination of paracetamol is a common need in pharmaceutical and environmental samples for which a low-cost, rapid, and accurate sensor would be highly desirable. We develop a novel pencil graphite lead electrode (PGE) modified with single-wall carbon nanotubes (SWCNTs) and polyvinylpyrrolidone (PVP) polymer (PVP/SWCNT/PGE) for the voltammetric quantification of paracetamol. The sensor shows remarkable analytical performance in the determination of paracetamol at neutral pH, with a limit of detection of 0.38 μM and a linear response from 1 to 500 μM using square-wave voltammetry (SWV), which are well suited to the analysis of pharmaceutical preparations. The introduction of the polymer PVP can cause dramatic changes in the sensing performance of the electrode, depending on its specific architecture. These effects were investigated using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM). The results indicate that the co-localization and dispersion of PVP throughout the carbon nanotubes on the electrode are key to its superior electrochemical performance, facilitating the electrical contact between the nanotubes and with the electrode surface. The application of this sensor to commercial syrup and tablet preparations is demonstrated with excellent results.

Standard and biochemical toxicological effects of zinc pyrithione in Daphnia magna and Daphnia longispina

Chemical toxicity in the environment may be the consequence of exposure of living organisms to multiple substances, with distinct putative effects. Among this mulytiplicity of chemicals that occur in the wild, pharmaceutical drugs and antifoulers are prone to exert toxic effects on non-target organisms. To characterize the toxicity elicited by a compound of this specific class, the present study used standard and biochemical-based tools to quantify the toxic response of the antifouler and antidandruff zinc pyrithione in Daphnia magna and Daphnia longispina. The analised parameters were immobility, reproduction, behavioral alteration (swimming patterns), anti-oxidant defense (catalase activity), metabolism (GSTs activities), and neurotoxicity (ChE activity) after exposure to sublethal concentrations of this drug. Exposure to zinc pyrithione has been shown to have neurotoxic and oxidative effects, with changes in swimming behavior. There were no changes in reproductive traits of exposed individuals, from both species. The obtained data demonstrate that ecologically relevant levels of zinc pyrithione can deleteriously alter critical parameters in two distinct freshwater microcrustacean species, although with distinct toxicity patterns and outcomes.

Exploring the Efficiency of UHPLC-Orbitrap MS for the Determination of 20 Pharmaceuticals and Acesulfame K in Hospital and Urban Wastewaters with the Aid of FPSE

Aside from the classical residues of persistent organic pollutants (POPs), the occurrence of emerging contaminants (ECs) in the environment has become a subject of increasing concern due to their harmful impact on the aquatic environment. Wastewater treatment plant (WWTP) effluents are major sources of environmental pollution. Therefore, data concerning their existence is required. In this study, twenty compounds representative of different drug groups considered ECs and belonging to antibiotics, antipsychotics, anti-inflammatory drugs plus acesulfame K were selected to be accurately detected and quantified with UHPLC–LTQ-Orbitrap MS in hospital and urban WWTP effluents. Chromatographic parameters (column efficiency, mobile phase, etc.), as well as mass spectrometry conditions concerning ionization mode and Orbitrap analysis (ESI options, mass resolving power, AGC target, tube lens, injection time), were evaluated. Moreover, a novel fabric phase sorptive extraction (FPSE) method based on fiber glass coated with PEG300 was employed as sample preparation process. Experimental parameters affecting extraction and desorption steps such as sample pH, extraction time, ionic strength, elution time and solvent have been optimized. The optimized methodology was validated providing excellent linearity (R2 > 0.99), and low detection and quantification limits up to 3.1 and 9.3 ng/L, for carbamazepine, respectively. Relative recoveries ranged from 81.1% to 114.0%, while a medium matrix effect for most of the target compounds occurred. Applying the above analytical method in effluents of WWTPs from NW Greece, nine compounds were quantified with concentrations that varied from 55.4 to 728.4 ng/L.

Simultaneous Analysis of Paracetamol and Diclofenac Using MWCNTs-COOH Modified Screen-Printed Carbon Electrode and Pulsed Potential Accumulation

A differential-pulse adsorptive stripping voltammetric (DPAdSV) procedure with the use of pulsed potential accumulation and carboxyl functionalized multiwalled carbon nanotubes modified screen-printed carbon electrode (SPCE/MWCNTs-COOH) was delineated for simultaneous analysis of paracetamol (PA) and diclofenac (DF). The use of carboxyl functionalized MWCNTs and pulsed potential accumulation improves the analytical signals of PA and DF, and minimizes interferences from surfactants. After optimization of analytical conditions for this sensor, the peak currents of the two compounds were found to increase linearly with the increase in their concentration (5.0 × 10^-9-5.0 × 10^-6 mol L^-1 with a detection limit of 1.4 × 10^-9 mol L^-1 for PA, and 1.0 × 10^-10-2.0 × 10^-8 mol L^-1 with a detection limit of 3.0 × 10^-11 mol L^-1 for DF). For the first time, the electrochemical sensor allows simultaneous determination of PA and DF at concentrations of 24.3 ± 0.5 nmol L^-1 and 3.7 ± 0.7 nmol L^-1, respectively, in wastewater samples purified in a sewage treatment plant.

Sulfamethoxazole/Trimethoprim ratio as a new marker in raw wastewaters: A critical review

Global Trimethoprim (TMP) and Sulfamethoxazole (SMX) occurrences in raw wastewaters were systematically collected from the literature (n = 140 articles) in order to assess the relevance of using the SMX/TMP ratio as a marker of the main origin of wastewaters. These two antibiotics were selected due to their frequent use in association (i.e. co-trimoxazole) in a 5:1 ratio (SMX:TMP) for medication purposes, generating a unique opportunity to globally evaluate the validity of this ratio based on concentration values. Several parameters (e.g. sorption, biodegradation) may affect the theoretical SMX/TMP ratio. However, the collected data highlighted the good agreement between the theoretical ratio and the experimental one, especially in wastewater treatment plant influents and hospital effluents. Only livestock effluents displayed a very high SMX/TMP ratio, indicative of the very significant use of sulfonamide alone in this industry. Conversely, several countries displayed low SMX/TMP ratio values, highlighting local features in the human pharmacopoeia. This review provides new insights in order to develop an easy to handle and sound marker of wastewater origins (i.e. human/livestock), beyond atypical local customs.

The seasonal distribution and concentration of antibiotics in rural streams and drinking wells in the piedmont of North Carolina

The present study investigated 16 residential, rural well sites and respective nearby streams in the Piedmont of North Carolina over three different seasons to determine antibiotic presence and concentration. Fifteen antibiotics were detected in stream surface water, groundwater, and stream sediment compartments. Antibiotics detected representing penicillin, sulfonamide, macrolide, aminoglycoside, lincosamide, and quinolone groups. Sulfamethoxazole (SMX), sulfamerazine (SMR), danofloxacin (DAN), and erythromycin (ETM) were the most commonly detected among samples throughout the sampling period. Concentrations reported in the study ranged from 0 to 1740 ng/L in surface water and groundwater, and 0t378 μg/kg in stream sediment. There was a seasonal influence on antibiotic concentrations in each environmental compartment. Fall had the highest antibiotic concentrations for surface water and stream sediments overall, and groundwater concentrations were highest in the winter. Principal component analysis (PCA) was used to assess the correlation between environmental variables. Antibiotic concentrations correlated with groundwater pH, surface water pH, and surface water temperature. Non-metric multidimensional scaling (NMDS), used to display seasonal and environmental compartment data, demonstrated no discernible trend in the distribution of antibiotics over time. Human health risk assessments based on risk quotients (RQs). RQs from groundwater assessment shown no risk to children 6-11 years old, or adults 18 years old or older. Results from this study illustrate that the occurrence of antibiotics in streams and groundwater in the Piedmont of North Carolina is widespread and provide a basis for future studies investigating the occurrence of antibiotics in rural areas, especially where animal density is high. This work is important because it contributes to the paucity of information on antibiotic pollution in rural areas, and because it illustrates the importance of using a combined targeted and non-targeted approach to antibiotic pollution in streams and groundwater.

Monitoring pharmaceuticals in the aquatic environment using enzyme-linked immunosorbent assay (ELISA)-a practical overview

The presence of pharmaceuticals, which are considered as contaminants of emerging concern, in natural waters is currently recognized as a widespread problem. Monitoring these contaminants in the environment has been an important field of research since their presence can affect the ecosystems even at very low levels. Several analytical techniques have been developed to detect and quantify trace concentrations of these contaminants in the aquatic environment, namely high-performance liquid chromatography, gas chromatography, and capillary electrophoresis, usually coupled to different types of detectors, which need to be complemented with time-consuming and costly sample cleaning and pre-concentration procedures. Generally, the enzyme-linked immunosorbent assay (ELISA), as other immunoassay methodologies, is mostly used in biological samples (most frequently urine and blood). However, during the last years, the number of studies referring the use of ELISA for the analysis of pharmaceuticals in complex environmental samples has been growing. Therefore, this work aims to present an overview of the application of ELISA for screening and quantification of pharmaceuticals in the aquatic environment, namely in water samples and biological tissues. The experimental procedures together with the main advantages and limitations of the assay are addressed, as well as new incomes related with the application of molecular imprinted polymers to mimic antibodies in similar, but alternative, approaches. Graphical Abstract.

Comprehensive investigation of a wide range of pharmaceuticals and personal care products in urban and hospital wastewaters in Greece

Detection and quantification of Pharmaceutical and Personal care products (PPCPs) in wastewaters and aqueous samples is crucial in terms of environmental monitoring and risk assessment for these emerging contaminants in the environment. The majority of the studies on PPCPs in wastewaters involve analysis only of representative compounds for each class, while few studies reported for the analysis of several compounds from multiple classes of PPCPs in samples. In this light, the aim of this work was to develop a multiresidue analytical protocol based on solid phase extraction (SPE) coupled to liquid chromatography combined with tandem mass spectrometer-(LC-MS/MS) for simultaneous determination of 138 substances including 37 different classes of PPCPs that can be used for monitoring in wastewater. Hence, an extensive monitoring survey of PPCPs in four wastewater treatment plants (WWTPs) in three cities of North (Thessaloniki) and Central (Larisa, Volos) Greece region has been conducted. In addition, the occurrence of the target compounds in raw waters of effluents from two medium-size hospitals located in the Larisa Region was investigated. Analgesics-anti-inflammatories (paracetamol, diclofenac, ibuprofen, salicylic acid), diuretic (furosemide), antibiotics (amoxicillin, ampicillin, clarithromycin, azithromycin), anti-hypertensives (valsartan, irbesartan, telmisartan), psychiatric drugs (carbamazepine, venlafaxine, citalopram), stimulant (caffeine) and beta blockers (atenolol, metoprolol, pindolol) were among the most frequently detected compounds. The removal rates varied between the different therapeutic groups, as well within each therapeutic group, important variations in removal were observed, going from not eliminated to 100%. Mass loading distribution in the different WWTPs was also evaluated. Finally, the risk quotient approach (RQ) for single substances and the cumulative RQ for the classes of the target PPCPs was used in order to identify the potential ecotoxicological risk posed in the tree trophic levels of aquatic organisms.

Rapid and Sensitive Determination of Methylxanthines in Commercial Brands of Tea Using Ultra-High-Performance Liquid Chromatography-Mass Spectrometry

Recently, chromatographic techniques have the potential to be greener in order to reduce the environmental impact. In this work, a new simple, sensitive, efficient, and green analytical method based on UHPLC-MS has been developed for a quick determination of methylxanthines including caffeine, theobromine, and theophylline in tea. Under the optimum conditions, a baseline separation has been achieved within 30 seconds, using isocratic elution consisting of 90% water and only 10% acetonitrile at 0.5 mL/min flow rate (3 mL acetonitrile per hour). The mass spectrometer was operated with the SIR mode in ESI⁺. The developed method was found to be linear in the range of 0.03–5 μg/mL, with correlation coefficients greater than 0.9995 for the three compounds. The respective values of LOD were found to be 0.025, 0.015, and 0.01 μg/mL for caffeine, theobromine, and theophylline, respectively. The proposed assay was applied to 30 commercial tea samples of different brands. Both caffeine and theobromine were found in all tea samples with maximum concentration in sample no. 15, corresponding to 32.6 and 2.72 mg/g of caffeine and theobromine, respectively. On the contrary, theophylline was not detected at all in most samples. When compared with all previous studies that dealt with the same compounds in different matrices, the developed method was found to be the fastest, allowing high-throughput analyses with more than 100 samples/h. The results prove that the method is suitable for routine analysis of methylxanthines and to distinguish the quality of tea samples of various brands.

Recent Trends in Fast Liquid Chromatography for Pharmaceutical Analysis

Background:

Liquid chromatography is the workhorse of analytical laboratories of pharmaceutical companies for analysis of bulk drug materials, intermediates, drug products, impurities and degradation products. This efficient technique is impeded by its long and tedious analysis procedures. Continuous efforts of scientists to reduce the analysis time resulted in the development of three different approaches namely, HTLC, chromatography using monolithic columns and UHPLC.

Methods:

Modern column technology and advances in chromatographic stationary phase including silica-based monolithic columns and reduction in particle and column size (UHPLC) have not only revolutionized the separation power of chromatographic analysis but also have remarkably reduced the analysis time. Automated ultra high-performance chromatographic systems equipped with state-ofthe- art software and detection systems have now spawned a new field of analysis, termed as Fast Liquid Chromatography (FLC). The chromatographic approaches that can be included in FLC are hightemperature liquid chromatography, chromatography using monolithic column, and ultrahigh performance liquid chromatography.

Results:

This review summarizes the progress of FLC in pharmaceutical analysis during the period from year 2008 to 2017 focusing on detecting pharmaceutical drugs in various matrices, characterizing active compounds of natural products, and drug metabolites. High temperature, change in the mobile phase, use of monolithic columns, new non-porous, semi-porous and fully porous reduced particle size of/less than 3μm packed columns technology with high-pressure pumps have been extensively studied and successively applied to real samples. These factors revolutionized the fast high-performance separations.

Conclusion:

Taking into account the recent development in fast liquid chromatography approaches, future trends can be clearly predicated. UHPLC must be the most popular approach followed by the use of monolithic columns. Use of high temperatures during analysis is not a feasible approach especially for pharmaceutical analysis due to thermosensitive nature of analytes.

Semi-quantitative non-target analysis of water with liquid chromatography/high-resolution mass spectrometry: How far are we?

Combining high-resolution mass spectrometry (HRMS) with liquid chromatography (LC) has considerably increased the capability of analytical chemistry. Among others, it has stimulated the growth of the non-target analysis, which aims at identifying compounds without their preceding selection. This approach is already widely applied in various fields, such as metabolomics, proteomics, etc. The applicability of LC/HRMS-based non-target analysis in environmental analyses, such as water studies, would be beneficial for understanding the environmental fate of polar pollutants and evaluating the health risks exposed by the new emerging contaminants. During the last five to seven years the use of LC/HRMS-based non-target analysis has grown rapidly. However, routine non-target analysis is still uncommon for most environmental monitoring agencies and environmental scientists. The main reasons are the complicated data processing and the inability to provide quantitative information about identified compounds. The latter shortcoming follows from the lack of standard substances, considered so far as the soul of each quantitative analysis for the newly discovered pollutants. To overcome this, non-target analyses could be combined with semi-quantitation. This Perspective aims at describing the current methods for non-target analysis, the possibilities and challenges of standard substance-free semi-quantitative analysis, and proposes tools to join these two fields together.

Psychiatrics and selected metabolites in hospital and urban wastewaters: Occurrence, removal, mass loading, seasonal influence and risk assessment

The occurrence, removal, mass loading, seasonal influence and environmental risk assessment of nine psychiatric pharmaceuticals and four of their selected metabolites, were studied in one hospital and one urban wastewater treatment plant (WWTP) in Ioannina city, in northwestern Greece, providing information about the efficiency of the plants and their contribution into the final receiver's flow. Samples were collected from the influents and the effluents of the plants in different sampling campaigns, from July to December 2016. Analytical methodology was based on ultra-high performance liquid chromatography-Orbitrap high-resolution mass spectrometry, after solid-phase extraction through Oasis HLB cartridges. Concentrations in both WWTPs ranged between <LOQ and 1126.3 ng/L in the influents and between <LOQ and 1127.4 ng/L, in the effluents. Results indicated that venlafaxine and its metabolite O-desmethyl venlafaxine were the most frequently detected compounds in the influents and the effluents of both WWTPs. Metabolite to parent compound ratio ranged in the influents between 0.01 and 87.2 while in the effluents between 0.01 and 47.7. Based on mass loads in the influents, venlafaxine is consumed in high amounts (up to 67.1 mg/day/1000 inhab.), and consequently its metabolite O-desmethyl venlafaxine (up to 139.1 mg/day/1000 inhab.). Similarly to the influents, environmental emissions, were also higher for venlafaxine and O-desmethyl venlafaxine (10.1 and 13.3 mg/d/1000 inhab., respectively). Removal efficiencies in the hospital WWTP ranged from -100% to 98.9%, while in the city WWTP from -49.9% to 99.8%. Furthermore, an important outcome was the evaluation of the potential ecotoxicological risk, by means of risk quotients (RQs), where none of the target psychiatrics or their metabolites showed RQ above 1.

Occurrence of polybrominated diphenyl ethers, perfluorinated compounds, and nonsteroidal anti-inflammatory drugs in freshwater mussels from Latvia

The occurrence of polybrominated diphenyl ethers (PBDE), perfluorinated compounds (PFC), and nonsteroidal anti-inflammatory drugs (NSAID) in Latvian freshwater ecosystems was evaluated by using filter-feeding mussels as bioindicators. Twenty four samples of mussels were collected from freshwater bodies throughout the territory of Latvia during the summer of 2017. PBDE contamination was ubiquitous, reaching the highest total concentration of 193.2 pg g^-1 w.w. BDE-209 was the most abundant compound, followed by penta-BDE components BDE-49, -100, -99, -153, -154, and -47 in decreasing order. The levels of PFCs in Latvian mussels were generally lower than those reported from other regions. Perfluorooctanoic acid (PFOA) was more common in mussels than perfluorooctane sulfonate (PFOS). Ibuprofen was the only NSAID detected in mussels during this study (detection frequency 50%). The observed concentrations of this compound varied between 0.52 and 109 ng g^-1 w.w., being noticeably higher than reported by other authors. Overall, the results indicate that among the three analysed groups of contaminants, ibuprofen is present in Latvian freshwater environment at relatively high levels and further monitoring should be carried out.

The use of RP-HPLC-Q-TOF-MS as a powerful tool for wastewater composition profiling and selection of water pollution marker specific to wastewater contamination

Abstract

Limited drinking water resources and water pollution are one of the main worldwide problems. To reduce the consumption of fresh water resources, the use of treated wastewater has been proposed. The farmlands have been irrigated with wastewater for centuries, but the composition of used sewage has changed over the years. Recent research has revealed the presence of hundreds of new organic contaminants in many environmental waters, including wastewaters and their receivers. For this reason, wastewater profiling and monitoring are of high importance and urgent need. In this study, the HPLC–Q-TOF–MS has been used for the profiling of wastewater composition and evaluation of the water pollution markers belonging to emerging contaminants. Three different solid-phase extraction approaches were applied to obtain the best results. Compounds such as acesulfame-K, caffeine, carbamazepine, cyclamate, ibuprofen, methyl paraben, paracetamol, or saccharin were detected in raw wastewater samples, whereas only acesulfame-K, carbamazepine, and sucralose were found in effluent samples. It seems that these particular compounds might be chosen as water pollution marker specific to Polish communal sewages.

Graphical abstract

Application of liquid-liquid microextraction for the effective separation and simultaneous determination of 11 pharmaceuticals in wastewater samples using high-performance liquid chromatography with tandem mass spectrometry

A dispersive liquid-liquid microextraction method for the simultaneous determination of 11 pharmaceuticals has been developed. The method is based on a microextraction procedure applied to wastewater samples from different regions of Hungary followed by high-performance liquid chromatography with mass spectrometry. The effect of the nature of the extractant, dispersive solvent, different additives, and extraction time were examined on the extraction efficiently of the dispersive liquid-liquid microextraction method. Under optimal conditions, the linearity for determining the pharmaceuticals was in the range of 1-500 ng/mL, with the correlation coefficients ranging from 0.9922 to 0.9995. The limits of detection and limits of quantification were in the range of 0.31-6.65 and 0.93-22.18 ng/mL, respectively.