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Background Imidacloprid is among the most widely used insecticides and today is found in surface and ground water worldwide. It has been registered in the EU watchlist for monitoring. To prevent imidacloprid from entering water bodies, advanced oxidation processes (AOP) have been intensely researched. Photo-irradiation proved one of the most efficient methods to degrade and eliminate anthropogenic micropollutants from waters. The ecotoxicity assessment of photoinduced degradation and transformation products especially in the absence of reference standards is still heavily explored. Results In this study, UVA and UVC irradiation in combination with titanium dioxide P25 as photocatalyst were investigated for their degrading and eliminating effects and effectiveness on imidacloprid. Humic acid was used as natural organic matter additive. High-performance liquid chromatography coupled with high-resolution mass spectrometry allowed to identify and monitor imidacloprid and its degradation intermediates yielding seven new structures and concentration–time (c–t) profiles. The correlation of structures and the application of radical scavengers and photocatalyst helped distinguish between direct photoinduced and indirect hydroxyl radical-induced degradation mechanisms. The identification of hydroxylated products and intermediates indicated the indirect degradation pathway, which could be suppressed by addition of a radical scavenger. The absence of hydroxylated intermediates and fragments pointed towards the direct absorption-induced degradation. Two degradations products were traced back to the direct mechanism, whereas all other products followed the indirect mechanism. The ecotoxicity of the identified compounds was assessed by quantitative structure–activity relationship (QSAR) analysis. Most products were predicted as less ecotoxic. Ecotoxicity equivalents (ETEs) were introduced allowing a classified ranking of the products and an assessment of the overall hazardous potential of the irradiated solution at a given moment. Generally, the number of hydroxyl substituents was inversely correlated to ecotoxicity. From the c-t curves, time-dependent ETE profiles were established. Conclusions Structure elucidation and c-t profiles from liquid chromatography–high-resolution mass spectrometry allowed to distinguish between direct and indirect degradation mechanisms. Structure specific ecotoxicity assessment could be achieved through QSAR analysis. Ecotoxicity hazard was ranked based on ETEs. The time-dependent ETE profile proved suitable to reflect the effect of irradiation duration and allow to estimate the irradiation time required to eliminate ecotoxicity, which may be relevant for potential applications in wastewater treatment plants.

https://www.aimspress.com/fileOther/PIC/environmental/Environ-07-01-005.jpg The ubiquitous presence of pharmaceuticals in the aquatic environment is a worldwide problem of today. Current analytical methods reveal ever more pharmaceuticals in different water bodies. The concentrations in waters that are detectable reach nano-and picogram ranges, i.e., ppb and ppt levels. Observed concentrations amount to as high as few micrograms. Among the major entry paths are wastewater treatment plants, which are often unable to eliminate the pharmaceuticals sufficiently relying on their three conventional purification stages. Hence, pharmaceuticals enter the aquatic environment without desirable deconstruction. Thus, advanced wastewater treatment processes are under development to retain or eliminate these trace contaminants. According to Decision 2018/840, a watchlist of 15 contaminants of significant interest has been established for the monitoring of surface waters in the European Union. The contaminants include biocides and pharmaceuticals, among them three estrogens, estrone (E1), 17-β-estradiol (E2) and 17-α-ethinylestradiol, (EE2), the antibiotics azithromycin, clarithromycin and erythromycin of macrolide type, ciprofloxacin and amoxicillin of fluoroquinolone and betalactame type. This review will provide an overview of the currently explored and researched methods for the realization of a fourth purification stage in wastewater treatment plants. To this purpose, biological, chemical and physical purification processes are reviewed and their characteristics and potential discussed. The degradation efficacy of the pharmaceuticals on the EU-Watch list will be compared and evaluated with respect to the most promising processes, which might be realized on large scale. Last but not least, recent and novel pilot plants will be presented and discussed.

The Research Octane Number (RON) still is the major physical quantity for the characterization of fuels. Spectroscopy and multivariate data analyses have proven themselves alternatives to the traditional CFR motor. Yet, the utilization of handheld or fieldable instruments has been rarely reported rendering the feasibility of fast and simple near-pump RON determination debatable. In this study, the applicability of a handheld Raman and a portable 1H NMR spectrometer in combination with chemometrics is demonstrated on a laboratory sample training set and compared to NIR spectroscopy. Qualitative classification of a fuel sample is achieved through Principal Component Analysis. The performance of the fieldable spectrometers using Support Vector Regression for RON prediction is found at least equivalent to earlier studies with more sophisticated and expensive instruments. The analytical method and the validated qualitative and quantitative models are then applied to samples from gas stations. The goodness of the method is expressed both in terms of computational residual mean squared errors and the common experimental reproducibility and repeatability limits. Depending on the method 40–50% of the samples are predicted within 0.2 and 80–90% with 0.7 RON.

A handheld Raman spectrometer was used to determine the ripeness of peppers. Raman spectra were recorded non-invasively on the fruit surface. The spectroscopic data were transformed into a classification scheme referred to as the maturity index which allowed for attribution of the fruit stadium to four levels from immature to fully mature. Hot pepper and tomato ripening includes pectic polysaccharide depolymerization, chlorophyll degradation and carotenoid formation, among others. The latter were followed non-invasively by Raman spectroscopy. Two portable systems and one benchtop system were compared for their applicability and robustness to establish a suitable maturity index. Spectral acquisition, data treatment and multivariate data analysis were automated using a Matlab script on a laptop computer. The automated workflow provided a graphic visualization of the relevant parameters and results on-site in real time. In terms of reliability and applicability, the chemometric model to determine the maturity of fruits was compared to a univariate procedure based on the average intensity and ratio of three characteristic signals. Portable Raman spectrometers in combination with the maturity index or a chemometric model should be suitable to assess the stage of maturing for carotenoid-containing fruits and thus to determine ripeness on-site or during a sorting process in an automated manner.

Pharmaceuticals in waters represent a worldwide problem of today. Advanced oxidation processes (AOPs) are being researched for elimination of the ecological hazard. Among the substances, the fluoroquinolone antibiotic lomefloxacin was selected for investigation in this study. Lomefloxacin (LOM) was found in the German river Erft. Near and far ultraviolet (UVA, UVC) radiation were used as AOPs and compared for efficiency depending on pH, water matrix, and catalysts. Chemical kinetics description revealed that UVC at pH 8&ndash, 9 led to the fastest degradation of LOM. The catalysts hydrogen peroxide and titanium dioxide had only limited influence on the degradation rate. Seven novel transformation products were structurally identified by high-resolution higher-order mass spectrometry. Ecotoxicity of the novel and known compounds was assessed by quantitative structure-activity relationship (QSAR) analysis. In addition, irradiation time dependent minimal, and half-maximal inhibitory concentrations (MIC, IC50) of LOM solutions were determined and suggested as ecotoxicological hazard indicators. From MIC and kinetic rate constants, the irradiation time required for compound and activity removal could be predicted.

Commercial fuels are characterized by parameters, such as research octane number and contents of additives, such as ethanol, ethyl-t-butyl ether, ethyl-tert-methyl ether, olefins, etc. For fast and...

In this study, the photo-induced degradation of azithromycin (Azi), erythromycin (Ery) and tylosin (Tyl) was investigated. The three macrolides are regularly found in different kinds of water, and are thus considered a potential environmental risk. In search of efficient ways for elimination, the compounds were systematically irradiated with a polychromatic UVC light source emitting 185, 254 and discretely further up to 580 nm. Due to their specific structural features, the macrolides possess different optical absorption characteristics leading to photodegradation pathways with dissimilar kinetic properties. Hence, the photodegradation products and their kinetics were analyzed using high-performance liquid chromatography (HPLC) coupled to high-resolution time-of-flight mass spectrometry. Among the degradants, i.e. the products formed during UV irradiation, both sugar moieties and lactone macrocycles were observed. Applying a first order kinetic model, the half-life of Azi was determined as 1.0−3.7 min, that of Ery as 1.0−14.2 min depending on the reaction conditions. The two compounds possess much lower absorption cross-sections than Tyl, in particular at 254 nm. Their half-lives appeared at least three times higher than that of Tyl that has t1/2 of 0.2−1.0 min. Based on quantum efficiency considerations, it was assumed that the degradation of Ery and Azi was mainly due to hydroxyl radical formation, which originated from water irradiation below 200 nm, whereas Tyl experienced predominantly photo induced degradation. The photodegradants of Azi exhibited half-lives of over 200 min, whereas most of the photo-products of Ery and Tyl showed half-lives of less than 10 min. Photodegradation processes were investigated at pH 3, pH 7 and pH 9 and in the presence of hydrogen peroxide. Both the educts and the photo-products were degraded more rapidly under neutral and acid conditions.

Zusammenfassung Die Einheit von Musik, Sprache, Bewegung und Tanz ist ein zentraler Faktor in der entwicklungsorientierten Musiktherapie nach Gertrud Orff. Lieder, Reime und Verse haben vom Anfang an eine wichtige Rolle in diesem musiktherapeutischen Ansatz gespielt. Uber die Jahre wurden die Lieder und Verse den Veranderungen in der Patientenstruktur und in den Settings angepasst. Dieser Artikel beschreibt kurz die Grundlagen fur die Anwendung von Liedern und Sprache in der Musiktherapie und zeigt auf, wie diese mit sehr jungen Kindern und ihren Eltern, fur Gruppenarbeit mit Vorschulkindern und fur Gruppenarbeit mit Schulkindern angewendet werden. Zwei wichtige Entwicklungen sind der Einsatz von Songwriting und musikalischen Projekten. Diese werden anhand klinischer Beispiele veranschaulicht.

Numerous studies have been reported on today’s ubiquitous presence of antibiotics in surface waters causing the emergence of multidrug-resistant bacteria. Advanced water treatment procedures aim at the complete prevention and elimination of antibiotics from entering natural water bodies. In this study, photoinduced degradation processes using UVC-irradiation were applied toward selected fluoroquinolone, tetracycline, macrolide, and sulfonamide antibiotics. Photodegradation products were elucidated using high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS). Rate constants and quantum efficiencies were determined for the active substances and their photo-transformation products. As a measure of ecotoxicity, minimum inhibitory and half-maximal inhibitory concentrations were determined against the Gram-negative bacterium Pseudomonas fluorescens and the Gram-positive Bacillus subtilis in a standard assay format. These values were further recorded as a function of UV exposure time. The irradiation time-dependent increase of minimum inhibitory concentration (MIC) values agreed well with the kinetic models. After 10 min of irradiation, the compound solutions ceased to inhibit bacterial cell growth, indicating removal of the pharmaceutical activity. These findings were found in agreement with quantitative structure–activity relationship analysis. The combination of microbiological activity testing, molecular structure analysis, chemical kinetic investigation, and quantitative structure–activity relationship models proved to be able to predict irradiation times and evaluate potential ecotoxicological hazard of the irradiated drugs.

Current research is increasingly focusing on the ecotoxicity of anthropogenic micro-pollutants and their degradation and transformation products resulting from biological and chemical treatment processes. These products enter the aquatic environment through various routes and may endanger aquatic organisms and plants. In this study, five neonicotinoids from the EU watchlist and their degradation products induced by UVC irradiation were examined. All identified photoinduced degradation or transformation products were subsequently submitted to Quantitative Structure Activity (QSAR) analysis. Among the investigated structures, 15 substances already identified in previous studies and eleven new transformation products were analyzed. By using QSAR analysis, it became possible to predict ecotoxicity of individual substances with mere computational effort. Starting from the chemical structure, lower toxicity against green algae and invertebrates was predicted for the transformation products in general. For other aquatic target organisms, such as branchiopoda, actinopterygii and fathead minnow, the residual hazardous effect as compared to the initial compound depends on the presence of specific structural elements. For the neonicotinoids investigated, the cleavage or elimination of the nitrile or nitro group through the degradation process, was predicted to increase toxicity.

Monitoring pharmaceuticals throughout the water cycle is becoming increasingly important for the aquatic environment and eventually for human health. Targeted and non-targeted analysis are today's means of choice. Although targeted analysis usually conducted with the help of a triple quadrupole mass spectrometer may be more sensitive, only compounds previously selected can be identified. The most powerful non-targeted analysis is performed through time of flight mass spectrometers (TOF-MS) extended by a quadrupole mass analyzer (Q), as used in this study. Preceded by solid phase extraction and high-performance liquid chromatography (HPLC), the non-targeted approach allows to detect all ionizable substances with high sensitivity and selectivity. Taking full advantage of the Q-TOF-MS instrument, tandem mass spectrometry (MS/MS) experiments accelerate and facilitate the identification while a targeted MS method enhances the sensitivity but relies on reference standards for identification purposes. The identification of four pharmaceuticals from Rhine river water is demonstrated. The Rhine river originates in Tomasee, Graubünden, Switzerland and flows into the North Sea, near Southern Bight, The Netherlands. Its length amounts to 1232.7 km. Since it is of prime interest to effectively eliminate pharmaceuticals from the water cycle, the effect UV-C irradiation is demonstrated on a laboratory scale. This method allows fast degradation of pharmaceuticals, which is exemplarily shown for the macrolide antibiotic erythromycin. Using the above HPLC-Q-TOF-MS method, concentration-time diagrams are obtained for the parent drug and their photodegradation products. After establishing the equations for first-order sequential reactions, computational fitting allows the determination of kinetic parameters, which might help to predict irradiation times and conditions when potentially considered as fourth stage within wastewater treatment.

This study focuses on the degradation of the sulfonamide antibiotics, sulfadiazine, sulfamethazine, sulfamethoxazole, and sulfathiazole, using ultraviolet irradiation in various conditions. Different pHs were investigated in combination with the addition of hydrogen peroxide and further oxygen removal. High-performance liquid chromatography electrospray ionization ion-trap mass spectrometry was used to identify and elucidate degradation products and to establish concentration–time curves. Previously unknown degradation products could be characterized. Reaction rate constants of all compounds and transformation products were determined. The parent sulfonamides decayed according to first-order kinetics, while the concentrations of the transformation products varied with time according to a subsequent reaction of an intermediate product. Quantum efficiencies were analyzed for mechanistic purposes. As example, sulfamethoxazole was added to effluents from a wastewater treatment plant and irradiated. Phototoxicity and environmental hazard were assessed through quantitative structure-activity relationship computations. In addition, the minimal inhibition concentrations were determined for Pseudomonas fluorescens and Bacillus subtilis. Conclusions for UV-C irradiation as a fourth purification wastewater treatment stage were derived.