Quantification Approaches in Non-Target LC/ESI/HRMS Analysis: An Interlaboratory Comparison.

Nontargeted screening (NTS) utilizing liquid chromatography electrospray ionization high-resolution mass spectrometry (LC/ESI/HRMS) is increasingly used to identify environmental contaminants. Major differences in the ionization efficiency of compounds in ESI/HRMS result in widely varying responses and complicate quantitative analysis. Despite an increasing number of methods for quantification without authentic standards in NTS, the approaches are evaluated on limited and diverse data sets with varying chemical coverage collected on different instruments, complicating an unbiased comparison.

Metabolites are overlooked in environmental risk assessments and monitoring of pharmaceuticals: The case study of pantoprazole.

The proton-pump inhibitor pantoprazole (PPZ) is one of the most consumed pharmaceuticals worldwide. Despite its high usage, reported PPZ concentrations in environmental water samples are comparatively low, which can be explained by the extensive metabolism of PPZ in the human body. Since most previous studies did not consider human PPZ metabolites it can be assumed that the current environmental exposure associated with the application of PPZ is substantially underestimated.

Summary recommendations on "Analytical methods for substances in the Watch List under the Water Framework Directive".

The Watch List (WL) is a monitoring program under the European Water Framework Directive (WFD) to obtain high-quality Union-wide monitoring data on potential water pollutants for which scarce monitoring data or data of insufficient quality are available. The main purpose of the WL data collection is to determine if the substances pose a risk to the aquatic environment at EU level and subsequently to decide whether a threshold, the Environmental Quality Standards (EQS) should be set for them and, potentially to be listed as priority substance in the WFD. The first WL was established in 2015 and contained 10 individual or groups of substances while the 4th WL was launched in 2022.

Wide-scope target screening characterization of legacy and emerging contaminants in the Danube River Basin by liquid and gas chromatography coupled with high-resolution mass spectrometry.

A state-of-the-art wide-scope target screening of 2,362 chemicals and their transformation products (TPs) was performed in samples collected within the Joint Danube Survey 4 (JDS4) performed in 2019. The analysed contaminants of emerging concern (CECs) included three major categories: plant protection products (PPPs), industrial chemicals and pharmaceuticals and personal care products (PPCPs). In total, 586 CECs were detected in the samples including 158 PPPs, 71 industrial chemicals, 348 PPCPs, and 9 other chemicals.

Post-aerobic treatment to enhance the removal of conventional and emerging micropollutants in the digestion of waste sludge.

Low content of micropollutants in sewage sludge, essential to allow its safe re-use in agriculture, requires effective removals during the digestion phase. To this purpose, we investigated the performance of the anaerobic-aerobic sequential digestion process applied to real waste sludge in the removal of several classes of standard pollutants, i.e.

Comparing mass, retention time and tandem mass spectra as criteria for the automated screening of small molecules in aqueous environmental samples analyzed by liquid chromatography/quadrupole time-of-flight tandem mass spectrometry.

Rationale: The adoption of database screening using high-resolution liquid chromatography/mass spectrometry data is promising as a river water monitoring and surveillance tool but depends on the ability to perform reliable data processing on a large number of samples in a unified workflow. Strategies to minimize errors have been proposed but automated procedures are rare.

Methods: High-resolution LC/ESI-QTOFMS/MS in data-dependent MS acquisition mode was performed for the analysis of surface water samples by direct injection.

Nontarget analysis: A new tool for the evaluation of wastewater processes.

Strategies to determine the removal efficiency of micropollutants in wastewater treatment plants (WWTPs) are widely discussed. Especially the evaluation of the potential benefit of further advanced treatment steps such as an additional tertiary treatment based on ozonation or activated carbon have come into focus. Such evaluation strategies are often based on the removal behavior of known micropollutants via target or suspected analysis.

Biotransformation of gabapentin in surface water matrices under different redox conditions and the occurrence of one major TP in the aquatic environment.

Laboratory-scale incubation experiments in water/sediment systems were conducted to test the transformation behavior of the anticonvulsant gabapentin (GBP) under different environmental conditions (aerobic, anaerobic, with abiotic controls). GBP was transformed by biological processes as it was eliminated quickly under aerobic conditions (dissipation time 50% of initial concentration (DT): 2-7 days) whereas no decrease was observed under anaerobic conditions. Measurements via high resolution mass spectrometry (LC-Orbitrap-MS) revealed eight biological transformation products (TPs).

Quaternary (triphenyl-) phosphonium compounds: Environmental behavior and toxicity.

An analytical method based on high resolution mass spectrometry coupled with liquid chromatography (LC-HRMS) for 25 quaternary phosphonium compounds (QPCs) and derived phosphine oxides (POs) was developed and validated. To investigate the occurrence and fate of QPCs in the aquatic environment, water, suspended solids and sediments from the rivers Rhine and Elbe (upper and middle Elbe as well as tidal Elbe) were analyzed, as well as samples from tributaries bearing significant loads of QPCs. For the first time, the quaternary phosphonium compound tetrabutylphosphonium (BuP) was detected.

Nontarget Analysis via LC-QTOF-MS to Assess the Release of Organic Substances from Polyurethane Coating.

A novel approach was investigated for the assessment of leaching from a one-component polyurethane (1C-PU) coating used for hydraulic structures using nontarget analysis via LC-QTOF-MS. Leaching behavior of the 1C-PU coating was studied using experiments in which the coating was exposed to water for defined periods (6 h, 24 h, 3 d, 14 d). Three hardening durations for the 1C-PU coating were tested (0 h, 24 h, 14 d) as well as two water matrices (ultrapure water and river water), including a successive water renewal.

Benzotriazole UV stabilizers in sediments, suspended particulate matter and fish of German rivers: New insights into occurrence, time trends and persistency.

Benzotriazole UV stabilizers (BUVSs) are widely applied in plastics to prevent discoloration and to enhance product stability. This study describes for the first time the occurrence of nine different lipophilic BUVSs (UV-326, UV-320, UV-329, UV-350, UV-328, UV-327, UV-928, UV-234 and UV-360) in sediment, suspended particulate matter (SPM) and bream liver samples of German rivers. All investigated BUVSs were detected in sediments and SPM at concentrations in the low ng/g dry weight (dw) range.

Development and validation of a generic nontarget method based on liquid chromatography - high resolution mass spectrometry analysis for the evaluation of different wastewater treatment options.

A comprehensive workflow for using nontarget approaches as process evaluation tools was implemented, including data acquisition based on a LC-HRMS (QTOF) system using direct injection and data post-processing for the peak recognition in "full scan" data. Both parts of the approach were not only developed and validated in a conventional way using the suspected analysis of a set of spiked known micropollutants but also the nontarget analysis of a wastewater treatment plant (WWTP) effluent itself was utilized to consider a more environmental relevant range of analytes. Hereby, special focus was laid on the minimization of false positive results (FPs) during the peak recognition.

Quaternary Triphenylphosphonium Compounds: A New Class of Environmental Pollutants.

A nontarget screening using high-resolution mass spectrometry (HRMS) was established to identify industrial emerging contaminants in the Rhine River. With this approach, quaternary triphenylphosphonium compounds (R-Ph3P(+)) were identified as new emerging contaminants in the aquatic environment. The suggested chemical structures were elucidated by MS fragmentation and chemical databank searches and eventually confirmed via authentic standards.

Phytotoxicity of wastewater-born micropollutants--Characterisation of three antimycotics and a cationic surfactant.

Sewage sludge applied to soil may be a valuable fertiliser but can also introduce poorly degradable and highly adsorptive wastewater-born residues of pharmaceuticals and personal care products (PPCPs) to the soil, posing a potential risk to the receiving environment. Three azole antimycotics (climbazole, ketoconazole and fluconazole), and one quaternary ammonium compound (benzyldimethyldodecylammonium chloride, BDDA) that are frequently detected in municipal sewage sludge and/or treated wastewater were therefore characterised in their toxicity toward terrestrial (Brassica napus) and aquatic (Lemna minor) plants. Fluconazole and climbazole showed the greatest toxicity to B.

Non-target screening with high-resolution mass spectrometry: critical review using a collaborative trial on water analysis.

In this article, a dataset from a collaborative non-target screening trial organised by the NORMAN Association is used to review the state-of-the-art and discuss future perspectives of non-target screening using high-resolution mass spectrometry in water analysis. A total of 18 institutes from 12 European countries analysed an extract of the same water sample collected from the River Danube with either one or both of liquid and gas chromatography coupled with mass spectrometry detection. This article focuses mainly on the use of high resolution screening techniques with target, suspect, and non-target workflows to identify substances in environmental samples.

Evaluating the fate of six common pharmaceuticals using a reactive transport model: insights from a stream tracer test.

Quantitative information regarding the capacity of rivers to self-purify pharmaceutical residues is limited. To bridge this knowledge gap, we present a methodology for quantifying the governing processes affecting the fate of pharmaceuticals in streaming waters and, especially, to evaluate their relative significance for tracer observations. A tracer test in Säva Brook, Sweden was evaluated using a coupled physical-biogeochemical model framework containing surface water transport together with a representation of transient storage in slow/immobile zones of the stream, which are presumably important for the retention and attenuation of pharmaceuticals.

Fate of pharmaceuticals in rivers: Deriving a benchmark dataset at favorable attenuation conditions.

Pharmaceutical residues are commonly detected organic micropollutants in the aquatic environment. Their actual fate in rivers is still incompletely understood as their elimination is highly substance specific and studies often report contradictory results. To elucidate the ceiling of attenuation rates of pharmaceuticals in rivers we carried out a study at a river with favorable conditions for the elimination of organic micropollutants.

Reactive tracer test to evaluate the fate of pharmaceuticals in rivers.

The fate of pharmaceutically active substances in rivers is still only incompletely understood, especially as the knowledge transfer from laboratory experiments to the real world is complicated by factors like turbidity, hydrodynamics, or heterogeneity. Therefore, we performed a tracer test with pharmaceutically active substances to study their fate and the importance of individual attenuation mechanisms in situ. The experiment was carried out at a small stream in central Sweden.

Dynamics and attenuation of acidic pharmaceuticals along a river stretch.

While substantial knowledge on the occurrence of pharmaceuticals in the environment is available, their behavior and fate in surface waters is still poorly understood. Therefore, the aims of this study were to analyze the short-term dynamics of selected pharmaceuticals along a 13.6 km long river stretch downstream of a wastewater treatment plant (WWTP), and to quantify their attenuation by a mass balance approach.

Biodegradation of acidic pharmaceuticals in bed sediments: insight from a laboratory experiment.

Pharmaceutical residues are commonly detected micropollutants in the aquatic environment. Biodegradation in sediments is a potentially significant removal process for these compounds in rivers which is constrained by the transfer of water and solutes into the sediment. The aim of this study was to determine the combined effect of flow velocity and sediment dynamics and thus of water-sediment interactions on the attenuation of 6 acidic pharmaceuticals.