A risk-based human health exposure assessment (HHEA) model was developed to evaluate the exposure for humans in 4 circular economy (CE) routes investigated in 6 of the 7 case studies in the project PROMISCES. The HHEA is a probabilistic tool evaluating the risk posed to human health. The HHEA was applied to the following routes: 1) semi-closed drinking water cycle; 2) groundwater remediation; 3) water reuse for agricultural irrigation; and 4) nutrient recovery. Each of these exposure routes results in a product – drinking water or lettuce – which can be consumed by humans. For some routes, the exposure is purely theoretical, while for others, the entire process chain is investigated in the PROMISCES case study.

The HHEA is built on Bayesian principles and includes Bayesian updating, which enables assessment of risk under conditions of low data availability and high uncertainty. This is particularly useful for evaluation of substances such as PFAS and other industrial persistent, mobile and potentially toxic (iPMT) substances, the removal of which in treatment processes is not yet well studied in literature. The deliverable explains the different treatments, environmental matrices, and substances which were the focus of the initial assessment. It describes the construction of the HHEA model, with explanations of how different data types – literature data, site specific data, and modelled data – are used to update the prior probability of the removal factor for substances in a process. It also describes how non-technical processes, such as mixing or evaporation, have been included into the treatment trains evaluated. Finally, individual reference quotients for the substances are established, which are used to assess the relative risk of the final concentrations in the products which could be consumed by humans.

The Horizon 2020 project PROMISCES aims to increase the circularity of resources by overcoming barriers associated with the presence of PM(T)s in the soil-sediment-water system.

This deliverable provides guidance on how to co-create a solution strategy for dealing with PM(T)(s) in a circular economy. For this, we have used the experience and lessons learnt in the co-creation workshops organized within the PROMISCES project.

Currently, there is uncertainty about emissions of pharmaceuticals into larger closed ecosystems that are at risk such as the Baltic Sea. There is an increasing need for selecting the right strategies on advanced wastewater treatment. This study analysed 35 pharmaceuticals and iodinated X-ray contrast media in effluents from 82 Wastewater Treatment Plants (WWTPs) across Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland and Sweden. Measured concentrations from Finland and Denmark were compared to predicted effluent concentrations using different levels of refinement. The concentrations predicted by the Total Residue Approach, as proposed by the European Medicines Agency, correlated with R(2) of 0.18 and 0.031 to measured ones for Denmark and Finland, respectively and the predicted data were significantly higher than the measured ones. These correlations improved substantially to R(2) of 0.72 and 0.74 after adjusting for estimated human excretion rates and further to R(2) = 0.91 and 0.78 with the inclusion of removal rates in WWTPs. Temporal analysis of compound variations in a closely monitored WWTP showed minimal fluctuation over days and weeks for most compounds but revealed weekly shifts in iodinated X-ray contrast media due to emergency-only operations at X-ray clinics during weekends and an abrupt seasonal change for gabapentin. The findings underscore the limitations of current predictive models and findings (...) demonstrate how these methodologies can be refined by incorporating human pharmaceutical excretion/metabolization as well as removal in wastewater treatment plants to more accurately forecast pharmaceutical levels in aquatic environments.

Pathogen removal in managed aquifer recharge (MAR) systems is dependent upon numerous operational, physicochemical water quality, and biological parameters. Due to the site-specific conditions affecting these parameters, guidelines for specifying pathogen removal have historically taken rather precautionary and conservative approaches in order to protect groundwater quality and public health. A literature review of regulated pathogens in MAR applications was conducted and compared to up-and-coming indicators and surrogates for pathogen assessment, all of which can be gathered into a toolbox from which regulators and operators alike can select appropriate pathogens for monitoring and optimization of MAR practices. Combined with improved knowledge of pathogen fate and transport obtained through lab- and pilot-scale studies and supported by modeling, this foundation can be used to select appropriate, site-specific pathogens for regarding a more efficient pathogen retention, ultimately protecting public health and reducing costs. This paper outlines a new 10 step-wise workflow for moving towards determining robust removal credits for pathogens based on risk management principles. This approach is tailored to local conditions while reducing overly conservative regulatory restrictions or insufficient safety contingencies. The workflow is intended to help enable the full potential of MAR as more planned water reuse systems are implemented in the coming years.

https://www.ncbi.nlm.nih.gov/pubmed/36931188

Die Simulationsergebnisse mit SIMBA# zeigten, dass mit den neu entwickelten ammoniumbasierten Regelungen und dem Air-Cycling-Konzept für MBR die Belüftung bzw. den Energieverbrauch deutlich reduziert werden konnte.An der Pilotanlage wurde demonstriert, dass mit den optimierten MSR-Konzepten stabile Ablaufwerte von CSB und Stickstoff erzielt werden können, welche mit großen Energieeinsparungen verbunden sind. Getestet wurden die ammoniumbasierten Regelungen und das Air-Cycling. Aber auch angepasste alternative MSR-Konzepte zur Optimierung der Schlammrezirkulation auf Basis der Nitratkonzentration im Ablauf und der Redoxpotential-basierten Regelung für die Belüftung der Nitrifikation wurden optimiert und getestet. Auch hier konnten sehr gute Ablaufergebnisse erzielt werden in Verbindung mit Energieeinsparungen. Allerdings wurde auch festgestellt, dass die verwendete ionenselektive Elektrode für die kontinuierliche Messung von Ammonium im Ablauf im niedrigen Messbereich (1-2 mg/L NH4-N) keine zuverlässigen Daten für eine Steuerung liefern kann.Im Rahmen des Projektes wurde auch ein neues Vorhersagemodell für Membranfouling entwickelt, um das Fouling 7 bis 14 Tage im Voraus zuverlässig vorherzusagen. Das Modell wurde dabei sowohl mit den historischen Betriebsdaten validiert und auch in der Praxis an der Pilotanlage getestet und bestätigt. Zusätzlich wurde ein Entscheidungsunterstützungs-system erarbeitet, welche die Fehlersuche und Wartung deutlich erleichtert.