Screening of organic pollutants in urban wastewater treatment plants and corresponding receiving waters.

There is a lack of knowledge in environmental pollution of the anthropogenic contaminants in wastewater and surface water. Several organic compounds merit special attention, because of their potential risk to the aquatic environment. Therefore, gas chromatography-mass spectrometry-based screening analyses were performed in order to identify anthropogenic organic contaminants and to reveal information on the structural diversity of individual compounds and to characterize their environmental behavior. Wastewater samples from wastewater treatment plants in Germany, representing various capacities, and surface water samples from corresponding receiving waters were analyzed. Numerous substances were identified in the samples. Several compounds were treated inadequately during wastewater treatment, and their identification in surface waters highlights their potential impact on the aquatic environment. Contaminants were selected according to available information about their environmental relevance (e.g. persistence, bioaccumulation potential), their possible application or usage and their occurrence within the environment. Based on the results of this study, it is recommended that non-target screening analyses be undertaken to identify the structural diversity of anthropogenic organic contaminants and that further investigations of specific anthropogenic compounds be undertaken as a high priority.

Analytical method development for the determination of eight biocides in various environmental compartments and application for monitoring purposes.

The main objective of this study was the development of simple multi-parameter methods for the analyses of biocides in various environmental matrices (wastewater, surface water, and sewage sludge) for measurement and monitoring activities. Eight target substances (triclosan, methyltriclosan (transformation product of triclosan), cybutryne (Irgarol), and the azole fungicides propiconazole, tebuconazole, imazalil, thiabendazole, and cyproconazole) were chosen for determination in selected sample sets. For surface water and wastewater samples a solid-phase extraction (SPE) method and for sewage sludge samples an accelerated solvent extraction (ASE) were developed. The extracts were analyzed by gas chromatographic-mass spectrometric methods (GC/MS), and the analytical methods were checked to ensure sufficient sensitivity by comparing the limits of quantification (LOQs) to the predicted no effect concentrations (PNECs) of the selected biocides. For quality control, recovery rates were determined. Finally, developed methods were checked and validated by application on sample material from various matrices. Sampling took place in seven urban wastewater treatment plants and their corresponding receiving waters. The results revealed that the developed extraction methods are effective and simple and allow the determination of a broad range of biocides in various environmental compartments.