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.

Emission model to calculate the monthly load of pollutants entering various water bodies and watercourses via stormwater and wastewater via the separate sewer system, combined sewer overflows (CSOs) and wastewater treatment plant (WWTP) effluent.

This bachelor thesis examines the influence of precipitation events and urban stormwater runoff on the concentrations of persistent and mobile substances (PM) in Berlin's surface waters. The analysis includes concentrations of 69 substances from four substance groups (VOCs, PAHs, PFAS, pesticides) that were recorded at 24 surface water sampling sites. Using precipitation data from 32 locations in Berlin, the concentrations were categorized according to dry weather, rain, and heavy rain influence. Statistical analyses for comparing these categories were performed using the Kruskal-Wallis and Dunn tests. Additionally, the concentrations in the surface waters were compared to those in Berlin's stormwater runoff using box-whisker plots.

13 of the investigated substances show significantly higher concentrations during rainfall or heavy rain events. This can be attributed to the input of these substances into surface waters through rainwater runoff. Particularly PAHs show notable concentration increases in Berlin's surface waters during precipitation events. PFOA and PFOS, two representatives of the PFAS group, exhibit a more complex behavior pattern depending on precipitation events. During light rainfall, their concentrations in surface waters decrease, while heavy rain events lead to increased concentrations. For pesticides and VOCs, the results are less conclusive, partly due to limited data availability.

This analysis provides valuable insights into the transport of various substance groups within the urban water cycle. The findings expand the scientific basis for developing targeted protection measures for urban waters.