Zusammenfassung Die Geschichte der Trinkwasseraufbereitung ist nicht nur eine Abfolge technischer Innovationen, sondern ein Spiegel wissenschaftlicher Debatten, gesellschaftlicher Lernprozesse und nicht zuletzt persönlicher Überzeugungsarbeit engagierter Menschen. Die Wasserchemische Gesellschaft hat den Entwicklungsweg seit nunmehr hundert Jahren begleitet und wissenschaftlich geprägt. Der vorliegende Beitrag möchte den Weg nachzeichnen – sachlich fundiert, aber auch mit Blick auf Menschen und Kontroversen, die den Fortschritt erst möglich machten.
Highly polar contaminants are analytically challenging due to the substantial differences in their chromatographic retention and ionisation behaviour between compound groups. This communication evaluates a developed and validated ZICcHILIC-HRMS workflow as a complementary approach to an established anion IC-HRMS method for analysing selected highly polar contaminants in water. The study focuses on implementing polarity switching, comparing method-specific analyte coverage and deriving practical method-selection criteria. Polarity switching enabled the acquisition of both positively and negatively ionising compounds within a single ZICcHILIC-HRMS run, thereby improving the practical efficiency of the comparatively lengthy chromatographic workflow. A comparison with IC-HRMS revealed partially overlapping, yet distinct, analytical coverage. IC-HRMS remained advantageous for small, strongly polar anionic compounds due to direct injection, lower quantification limits, shorter runtime and higher routine robustness. In contrast, ZICcHILIC-HRMS extends the accessible analyte spectrum to compounds outside the scope of the applied anion IC-HRMS and to analytes that can be detected in positive electrospray ionisation mode. These findings support the use of ZICcHILIC-HRMS as a complementary, LC-HRMS-compatible tool for the exploratory monitoring of highly polar contaminants in water, particularly when both ionisation modes and conventional HPLC-HRMS instrumentation are to be employed.
Highly polar and mobile organic substances challenge water analysis due to their persistence, high solubility, and incomplete removal during conventional drinking-water treatment. Their ionic or ionisable nature makes them suitable for ion chromatography coupled to high-resolution mass spectrometry (IC-HRMS), enabling direct injection of aqueous samples and retention of small anions. In this study, an IC-HRMS method was developed and validated for 23 highly polar contaminants, including haloacetic acids, pesticide transformation products, and other mobile and persistent compounds. Limits of quantification ranged from 0.03 to 0.37 µg/L in a linear range of 0.01–100 µg/L. Autosampler-based co-injection of stable isotope–labelled internal standards enabled continuous quality control of retention time, signal intensity, and mass accuracy. Retention time deviations over 4 months of measuring remained below 12 s and mass deviations below 2 ppm, demonstrating robust performance. Application to samples along the drinking-water treatment train confirmed the presence of persistent and mobile substances in the low µg/L range, including trifluoroacetic acid, sulfamic acid, cyanuric acid, and chlorothalonil transformation products. These results demonstrate that IC-HRMS with automated co-injection is a reliable tool for routine monitoring of highly polar anionic contaminants in water.
RATIONALE:The quality of analytical measurements is typically evaluated after completion of the entire, or possibly multiple, measurement batch(es). Automated, near real-time quality control (QC) during LC-HRMS acquisition can prevent reruns and sample loss by flagging issues as they occur. Functionality was evaluated by retrospective application to 5 years of river-water surveillance. METHODS:We present a modular MATLAB workflow that tracks isotopically labelled internal standards for peak height, retention time and mass error against rolling, method-specific expectations; applies multivariate statistical process control (MSPC; PCA with Hotelling's T2 and SPE on intensity/retention time ratios and mass error); issues immediate email alerts; and logs outcomes to a PostgreSQL database/Grafana dashboard for trend analysis. Also, qualitative target screening via cosine-similarity MS2 checks against a local library, retention time correction, robust peak-height/noise estimation, configurable limits and automated vendor-to-open format conversion. RESULTS:In a high-voltage power-supply failure, 25/25 injections were flagged due to abnormal intensity patterns; during an organic-pump malfunction, 17/25 were flagged for retention drift up to and beyond the extraction window; and during an air-conditioning (AC) outage, MSPC detected mass error anomalies even when the ±10 ppm univariate limit was not breached. MSPC closely agreed with univariate thresholds: 95.7% of samples flagged by univariate rules were also flagged by MSPC (≈4.3% Type II), while 92.5% of MSPC-flagged samples violated at least one univariate rule (≈7.5% Type I). CONCLUSION:These capabilities enable immediate detection, triage and documentation of performance excursions, support proactive maintenance (e.g., column aging or pump delivery issues), minimise downtime and safeguard precious samples. Although showcased on a specific LC-HRMS setup and matrix, the workflow is instrument-agnostic and broadly applicable to internal-standardised LC-HRMS methods.
The herbicide glyphosate and aminomethyl phosphonic acid (AMPA), a transformation product of glyphosate and other aminopolyphosphonates are widespread pollutants in European rivers. We recently showed that besides rain-driven input after agricultural or urban herbicide application, municipal wastewater significantly contributes to glyphosate contamination in European rivers. The rather constant mass fluxes over the year, made an explanation by herbicide applications difficult. In our search for a new source of glyphosate and AMPA, we here provide experimental evidence that a certain aminopolyphosphonate, used as antiscalant and bleach stabilizer in household detergents and numerous industrial processes, is a precursor of both glyphosate and AMPA. During incubation experiments with diethylenetriamine penta(methylene phosphonic acid) (DTPMP) in fresh activated sludge, we observed the formation of glyphosate with yields ranging from 0.017 to 0.040 mol% and formation of AMPA in the range of 0.402 to 1.72 mol% after 72 h. Both compounds are formed from DTPMP and possible intermediates, but they are also further transformed themselves in consecutive reactions. Glyphosate formation from DTPMP was further proven by incubating 13C-labeled DTPMP, which transformed into 13C-glyphosate and 13C-AMPA. The addition of DTPMP to azide-treated activated sludge yielded similar or even higher glyphosate and AMPA concentrations indicating that abiotic processes dominate the transformation process. In order to judge the relevance of this in-situ formation of glyphosate and AMPA from the laundry additive DTPMP, we estimated the average concentrations in wastewater.
