Publications by authors named "Heidemarie Schaar"

The present work aimed to study the effect of ozonation on the organic sum parameters linked to enhanced biodegradability. Laboratory experiments were conducted with the effluent of four Austrian urban wastewater treatment plants with low food to microorganism ratios and different matrix characteristics. Biochemical oxygen demand over 5 days (BOD) was measured before ozonation and after application of different specific ozone doses (D) (0.

View Article and Find Full Text PDF

Several thousands of highly persistent per- and polyfluoroalkyl substances (PFAS) exist and it is therefore challenging to analytically determine a larger spectrum of these compounds simultaneously in one sample. It is even more difficult to efficiently remove mobile PFAS in wastewater treatment plants (WWTPs) to protect the receiving waters. The total oxidizable precursor (TOP) assay is an approach that enables the detection of the total PFAS content in a sample via oxidation of precursors, followed by subsequent analysis of the perfluoroalkyl acid (PFAA) concentration before and after oxidative processes.

View Article and Find Full Text PDF

Aim of this study was to investigate the impact of advanced wastewater treatment techniques (combining ozonation with activated carbon filtration) on acute and genotoxic activities of tertiary treated wastewater. Concentrated samples were tested in Salmonella/microsome assays. Furthermore, induction of DNA damage was measured in liver-derived cells (human hepatoma and primary rat hepatocytes) in single cell gel electrophoresis experiments, which are based on the measurement of DNA migration in an electric field.

View Article and Find Full Text PDF

Conventional urban wastewater treatment plants (UWTPs) are poorly effective in the removal of most contaminants of emerging concern (CECs), including antibiotics, antibiotic resistant bacteria and antibiotic resistance genes (ARB&ARGs). These contaminants result in some concern for the environment and human health, in particular if UWTPs effluents are reused for crop irrigation. Recently, stakeholders' interest further increased in Europe, because the European Commission is currently developing a regulation on water reuse.

View Article and Find Full Text PDF

Urban wastewater treatment plants (WWTPs) are among the main anthropogenic sources for the release of contaminants of emerging concern (CECs) into the environment, which can result in toxic and adverse effects on aquatic organisms and consequently on humans. Unfortunately, WWTPs are not designed to remove CECs and secondary (e.g.

View Article and Find Full Text PDF

The study aims to simultaneously control micropollutants and bromate formations by using ozonation and peroxone process. The batch experiments were run with variations in specific ozone dose (SOD) and hydrogen peroxide-to-ozone (HO/O) ratio. Based on the removal by ozonation and peroxone, micropollutants were categorized into three groups: non-reactive compounds (i.

View Article and Find Full Text PDF

Tertiary wastewater treatment plant effluent before and after ozonation (0.6-1.1g O₃/g DOC) was tested for aquatic ecotoxicity in a battery of standardised microbioassays with green algae, daphnids, and zebrafish eggs.

View Article and Find Full Text PDF

The design criteria for wastewater treatment plants (WWTP) and the sludge retention time, respectively, have a significant impact on micropollutant removal. The upgrade of an Austrian municipal WWTP to nitrogen removal (best available technology, BAT) resulted in increased elimination of most of the analyzed micropollutants. Substances, such as bisphenol-A, 17alpha-ethinylestradiol and the antibiotics erythromycin and roxithromycin were only removed after the upgrade of the WWTP.

View Article and Find Full Text PDF