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routineda - identifying pollutants in effluent

The antibiotics assay that was developed within the RoutinEDA project is currently being used to identify antimicrobial substances in effluent. We want to know the identity of these compounds, as they may be of concern to environmental and human health. Effluent samples (water discharged by sewage treatment plants (WWTPs)) from the E-PRTR sampling campaign are used in the current study. E-PRTR is an abbreviation for 'European Pollutant Transfer Register', a European regulation stating that sewage treatment plants should report on emissions.

We are screening the effluent of six WWTPs, sampled at two different time points. Using a technique called effect-directed analysis (EDA), which combines chemical and biological measurements, we aim to identify antimicrobials with a response in the bioassay. In addition to antimicrobial activity, we are applying the GR-CALUX bioassay for the identification of glucocorticoids. This is done in collaboration with Het Waterlaboratorium, a member of the RoutinEDA user committee.

Enriched water samples are fractionated with liquid chromatography and a fraction collecting apparatus (the FractioMateTM device). The resulting fractions are collected in well plates, on which the bioassays are applied. Samples are also measured on a high-resolution mass spectrometer. The fractions with bioactivity are used to guide identification efforts in the mass spectrometry data by applying suspect- and nontarget screening techniques.


Figure 1. The antibiotics bioassay response, where bacterial growth is plotted against (fractionation) time. Some fractions show antimicrobial activity. 


Figure 2. The FractioMateTM device (left) is used to fractionate the samples eluting from the LC-column (right). A QTOF (middle), a high-resolution mass spectrometer, is used to detect the thousands of accurate masses.


CER-CEC: From toilet to river

Efforts of three NWO-TTW projects on chemicals of emerging concern were combined and led to the publication of an H2O article. Lara Schuijt (WUR), Caterina Zillien and Tamara van Bergen (RU) present a framework for micropollutants (“from toilet to river”) and elaborate on this with a case study of fluoxetine in Nijmegen.

The article describes which insights and results the combined projects are expected to deliver. From the preliminary case study, they conclude that the quality of input data is of crucial importance in order to make valuable emission estimates and to do an acceptable risk assessment. As researchers, we are always looking for more data! So if you can help us with relevant datasets, please contact us (This email address is being protected from spambots. You need JavaScript enabled to view it.).

The article is in Dutch and you can find it here:


Bergen Figuur2

SUSPECt: Start Sampling Campaign urban case

On Thursday 19 September, the fieldwork for the urban case of the SUSPECt project started. At four locations throughout Nijmegen we placed small sponges (passive samplers) in the sewer to assess the CEC composition of different wastewater types (domestic, industrial, surface run-off). These sponges remain in the underworld for one to 6 weeks until we retrieve them again and take them to the laboratory for further analysis. We expect to obtain the first results in November.

The start of the sampling campaign was covered by the media including OmroepGelderland and Radboud University’s magazine VOX.

Preparing the sponges before placement. Photo: Dick van Aalst.


Media attention during fieldwork. Photo: Dick van Aalst.


routineda: Development of an antibiotics screening assay – the sampling of hospital water

As part of the RoutinEDA project and as an expansion of the current Effect-directed Analysis platform, we are developing a bioassay that detects the presence of antibiotics in environmental matrices such as water and soil. Bacteria that have been made increasingly susceptible to antibiotics are exposed to concentrated environmental extracts. The inhibition of bacterial growth may indicate the presence of antibiotic-like compounds in the samples.   

In the first week of February 2019, we collected effluent water directly from a hospital in Arnhem. We will screen for antibiotics in the extracts that will be prepared from the samples, using the developed bioassay.

We thank Arnhem municipality for providing the opportunity to sample.


Project update: cost effective removal of Cecs

Our project 'Cost-Effective Removal of Contaminants of Emerging Concern' started in January, last year, when Ana Belén Ríos Miguel began her PhD at the department of Microbiology at the Radboud University (RU). A few months later, Tamara van Bergen started her PhD at the department of Environmental Science (RU). Together with all project supervisors, Rosalie van Zelm, Ad Ragas, Cornelia Welte, Mike Jetten and project leader Jan Hendriks, we really enjoy the synergistic cooperation of our departments in the CER-CEC project!


On the left picture Tamara van Bergen is measuring samples of a pilot experiment at the GC-MS, and on the right, Ana Rios is preparing nitrifying bioreactors. In the near future, we will grow our own CER-CEC microbial communities!

In October, we presented our first results to the stakeholders of our project. Several waterboards, drinking water companies, water technology companies, and governmental agencies are involved in our project. They were very enthusiastic in the first kick-off meeting and together we discussed the list of chemicals to be investigated in the project, and the selected of suitable wastewater treatment plants to be sampled. We presented our first objectives towards our shared goal: on the one hand assessing and prediction biodegradation of CECs (Environmental Science) and on the other hand optimizing CEC removal and working towards an application (Microbiology). The first results of a shared pilot experiment were presented, which will lead to an assessment of biodegradation rates of several chemicals of emerging concern. At the moment, the biodegradation assays still need optimization and a method for measuring our chemicals in wastewater samples needs to be developed. We will work on those topics the coming period and in addition, Ana Rios will also focus on starting up bioreactors and enrichment experiments. In the meantime, Tamara van Bergen will gain more knowledge on how biological mechanisms affect biodegradation of chemicals and will explore ways to include microbial community changes into biodegradation models. This is expected to lead to an increased understanding and prediction of biodegradation in wastewater treatment plants.

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