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Transformation products (TPs) may be formed during various processes, however, it was proved that one of the main mechanisms responsible for degradation of pharmaceuticals in natural waters is photolysis. Three compounds were selected, tetracycline (TC), 17-α-ethinylestradiol (EE2) and naproxen (NAP), for degradation experiments which were performed using a xenon lamp emitting light with a spectrum closely approximating that of natural sunlight. Identification of photodegradation products was achieved via liquid chromatography coupled with high resolution quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) providing accurate mass measurements and MS/MS experiments for structural elucidation. Results indicate that degradation of compounds under the study follows pseudo-first-order kinetics. Photolysis rate constants (k) were determined and half-lifes (t1/2) calculated to be 11, 120, and 13 min for TC, EE2 and NAP, respectively. Xenon lamp irradiation led to the formation of several photoproducts. Many of them have been identified for the first time. LC-QTOF-MS analysis allowed for the identification of seven, four, and eight TPs of TC, EE2 and NAP, respectively. Finally, the presence of parent compounds and identified TPs was investigated in various real-world water samples. Only three degradation products of 17-α-ethinylestradiol and naproxen were detected in wastewater effluent and treated water samples. Quantitative structure-activity relationship (QSAR) approach was applied in order to estimate physical-chemical properties of selected pharmaceuticals and their TPs. This allowed predicting the fate of all analytes in the aqueous environment.

Aquatic organisms from freshwater ecosystems impacted by waste water treatment plant (WWTP) effluents are constantly exposed to constant concentrations of pharmaceuticals, endocrine disruptors and related compounds, among other anthropogenic contaminants. Macroinvertebrates inhabiting freshwater ecosystems might be useful bioindicators of exposure to contaminants, since their lives are long enough to bioaccumulate, but at the same time may integrate short-term changes in the environment. However, studies about potential bioaccumulation of emerging contaminants in these organisms are very scarce. The objectives of this study were to develop an analytical methodology for the analysis of 41 pharmaceuticals and 21 endocrine disruptors in freshwater invertebrates. In addition, bioaccumulation of these contaminants in three macroinvertebrate taxa inhabiting a waste water treatment plant -impacted river was evaluated. The method for the simultaneous extraction of both families of compounds is based on sonication, purification via removal of phospholipids, and analysis by ultra performance liquid chromatography coupled to a mass spectrometer (UPLC-MS/MS) in tandem. Recoveries for pharmaceuticals were 34-125%, and for endocrine disruptors were 48-117%. Method detection limits (MDLs) for EDCs were in the range of 0.080-2.4 ng g-1, and for pharmaceuticals, 0.060-4.3 ng g-1. These pollutants were detected in water samples taken downstream the waste water treatment plant effluent at concentrations up to 572 ng L-1. Two non-esteroidal anti-inflammatory drugs, diclofenac and ibuprofen, and four endocrine disruptors - estrone, bisphenol A, TBEP, and nonylphenol - were detected in at least one macroinvertebrate taxa in concentrations up to 183 ng g-1 (dry weight). An isobaric interference was identified during the analysis of diclofenac in Hydropsyche samples, which was successfully discriminated via accurate mass determination by TFC-LTQ Orbitrap This study has been financed by Spanish Ministry o fEconomy and Competitiveness through the project SCARCE (Consolider-Ingenio 2010CSD200900065). This work was partly supported by the Generalitat de Catalunya (Consolidated Research Group: Catalan Institute for water Research 2014 SGR 291)

Several thousand tons of pharmaceuticals and their transformation products (metabolites and degradation products) are introduced into the environment each year. They affect both human health and the environment, therefore, analytical procedures enabling the determination of a wide range of pharmaceuticals at trace levels with minimal effort, time, and energy are required. Nowadays, hyphenated techniques are commonly applied in pharmaceutical analysis. This article provides a brief overview of the state-of-the-art and future trends in the determination of pharmaceutical residues and their transformation products with a focus on the most popular techniques in the field, such as ultra or high-performance liquid chromatography (UHPLC or HPLC) coupled with tandem mass spectrometry (MS/MS), quadrupole time-of-flight (QTOF), and a hybrid quadrupole/linear ion trap (QqLIT) in different environmental matrices (water, soil/sediment). Attention is paid to different aspects, benefits, and limitations of the application of UPLC and mass spectrometry-based techniques.

The identification and determination of transformation products (TPs) of pharmaceuticals is essential nowadays, in order to track their fate in the aqueous environment and, thus, to estimate the actual pollution. However, this is a challenging task due to the necessity to apply high-resolution instruments enable to detect known and unknown compounds. This work presents the use of liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) as a powerful tool for the identification of three selected pharmaceuticals, furosemide (FUR), ibuprofen (IBP), and ketoprofen (KET), and their TPs in various water samples. Laboratory degradation experiments were performed using xenon lamp as a source of the irradiation in order to simulate phototransformation processes which may occur in the environment. Furthermore, the photodegradation kinetics of three selected compounds were assessed in a reactor equipped with xenon lamp in river water samples. Five TPs of IBP, seven of KET, and five of FUR were identified; some of them are presented here for the first time. Accurate mass measurements and fragmentation pattern obtained during an LC-QTOF-MS analysis allowed for structure elucidation of TPs followed by the creation of transformation pathway of selected pharmaceuticals. Finally, different water samples (wastewater influent and effluent, river water, untreated and treated water) were analyzed in order to estimate the presence of parent and transformed compounds. Only KET was detected in untransformed form in considered samples. Most of the TPs of selected drugs were found at least once in all water samples. Although IBP and FUR were not present in water samples as parent compounds, their different TPs occur. A great potential of LC-QTOF-MS in the identification and structural elucidation of TPs in the environment, allowing the recognition of the fate of pharmaceuticals in the environment through the determination of transformation pathway, has been presented. Phototransformation of three selected pharmaceuticals Electronic supplementary material The online version of this article (doi:10.1007/s00216-014-7614-1) contains supplementary material, which is available to authorized users.

A new sensitive method based on pressurized liquid extraction (PLE) and purification by gel permeation chromatography (GPC) prior to ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) was developed for the determination in fish homogenate, liver and muscle of twenty pharmaceuticals compounds and metabolites from seven commonly used therapeutic families. An extensive matrix effect evaluation was performed in order to select the best approach when analyzing such complex matrices. Limits of detection (MDLs) for the target compounds were in the range of 0.03-0.50ng/g for fish homogenate, 0.01-0.42ng/g for fish muscle, and 0.08-0.98ng/g for fish liver. The method was applied to fish tissues of eleven fish species from four heavily impacted Mediterranean rivers. Nine compounds from five therapeutic families were measured at concentrations higher than MDLs. Highest levels were found in trout liver, with a maximum concentration of 18ng/g for carbamazepine, whereas the most ubiquitous compound was diclofenac.

Thousands of tons of pharmaceuticals are introduced into the aqueous environment due to their incomplete elimination during treatment process in wastewater treatment plants (WWTPs) and water treatment plants (WTPs). The presence of pharmacologically active compounds in the environment is of a great interest because of their potential to cause negative effects. Furthermore, drugs can undergo different processes leading to the formation of new transformation products, which may be more toxic than the parent compound. In light of these concerns, within the research a new, rapid and sensitive analytical procedure for the determination of a wide range of pharmaceuticals from different classes using solid phase extraction (SPE) and high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) technique in different water samples was developed. This methodology was applied to investigate the occurrence, removal efficiency of 25 pharmaceuticals during wastewater and drinking water treatment, and seasonal variability in the amount of selected pharmaceuticals in WWTP and WTP over a year. The most often detected analytes in water samples were carbamazepine (100 % of samples) and ibuprofen (98 % of samples), concluding that they may be considered as pollution indicators of the aqueous environment in tested area. Highly polar compound, metformin, was determined at very high concentration level of up to 8100 ng/L in analyzed water samples. Drugs concentrations were much higher in winter season, especially for non-steroidal inflammatory drugs (NSAIDs) and caffeine, probably due to the inhibited degradation related to lower temperatures and limited sunlight. Carbamazepine was found to be the most resistant drug to environmental degradation and its concentrations were at similar levels during four seasons.

Distillation Cleanup Preceded GC Determination of Short-Chain Monocarboxylic Acids in Aqueous and Solid Samples of Wastewater OriginShort-chain monocarboxylic acids (SCMAs) (C2-C5) formed in the process of aerobic biodegradation of larger organic molecules should often be monitored to optimize wastewater biological treatment and study the processes of converting organic waste matter into methane, etc. Gas chromatography (GC) seems a method of choice for such a task. Majority of samples require clean up before they can be injected into GC system. In this work a special refluxing apparatus is applied to concentrate and clean up the troublesome environment samples before injection into GC. To optimize separation of SCMAs in aqueous sample a special arrangement of two capillary columns, of very different polarity was used. The operational parameters of sample preparation were optimized and enrichment factors determined. The procedure developed was applied to determine SCMAs in troublesome aqueous and solid samples of wastewater treatment origin.

Experimental studies were conducted to investigate the photodegradation of diazepam and sertraline, two of the most frequently used psychiatric drugs, induced by xenon lamp irradiation, which overlap the sunlight spectra, and natural sunlight. Degradation kinetics was established indicating the occurrence of autocatalytic reactions. The application of liquid chromatography coupled to quadrupole time-of-flight mass spectrometry allowed for accurate mass measurements and proper fragmentation of target compounds enabling structure elucidation of various photoproducts of diazepam and sertraline formed during the forced photolysis. As a result, phototransformation pathways were proposed including the compounds and routes of degradation described here for the first time. In the final step, the presence of parent and identified compounds was examined in various environmental water samples. Although, the analytes were non-detected it was assumed that they may undergo different process in the environment such as adsorption, dilution, advection or rapid photodegradation of all compounds.

A new, sensitive and rapid method based on QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) approach followed by ultra high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) was developed for the determination of nineteen endocrine disruptors (EDCs) and related compounds belonging to different classes in various fish species. Matrix effect on the analytical performance was evaluated, and thus, internal sample calibration was chosen as the most appropriate approach when analyzing such complex matrices as biota. The procedure provided adequate recoveries in the range from 40% to 103% for most of the compounds, low method detection limits (MDLs) in the range from 0.002 to 3.09ng/g for fish homogenates and high accuracy

In the present study, an analytical procedure was developed for the determination of short-chain fatty acids (SCFAs) in landfill leachate and municipal wastewater employing injection of aqueous samples to gas chromatograph with flame ionization detector (GC-FID). Chromatographic conditions such as a separation system, injection volume, oven temperature program were investigated and selected. With two columns, one with a polar (polyethylene glycol) and one with a non-polar (dimethylpolisiloxane) stationary phase, good separation of SCFAs, containing from 2 to 8 carbon atoms, was achieved. The sample volume was 2 μL and the temperature program 80 °C (30 s) then 7 °C min −1 to 220 °C (2 min). LOQs values were below 0.25 mg L −1 . The concentrations of the acids in the landfill leachate studied ranged from 0.45 ± 0,059 (average ± extended uncertainty) mg L −1 for pentanoic acid to 15.2 ± 0.73 mg L −1 for ethanoic acid. Concentrations of SCFAs in the municipal wastewater were lower than LOQs.

Nowadays, monitoring focuses on the primary compounds and does not include degradation products formed during various biological and chemical processes. Transformation products may have the same effects to human health and the environment or sometimes they can be more toxic than the parent compound. Unfortunately, knowledge about the formation of degradation products is still limited, however, can be very important for the environmental risk assessment. Firstly, the photodegradation kinetic of amlodipine was investigated in two experimental conditions: during the exposure to solar radiation and during the exposure to the light emitted by the xenon lamp. In all cases degradation of amlodipine followed a pseudo-first-order kinetics. In the next step, identification of transformation products of amlodipine formed during the exposure to xenon lamp irradiation was performed using ultra high performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS). As a result sixteen photoproducts were identified, their structures were elucidated and ultimately the transformation pathway was proposed. Fifteen compounds (out of 16 photoproducts) were newly identified and reported here for the first time; some of those compounds were formed from the first photoproduct, amlodipine pyridine derivative. Several analytes were formed only in acidic or basic conditions. Furthermore, the occurrence of amlodipine and its identified degradation products was investigated in environmental waters. Only one out of 16 compounds was found in wastewater effluent. The possibility of the sorption of examined analytes to sewage sludge particles was discussed based on QSAR.