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.

This Layman's report is part of Deliverable D6.6 showcasing H2020 PROMISCES project outcomes and results.

The PROMISCES project aims to develop innovative, systemic solutions to protect health, environment, and natural resources from persistent, mobile and potentially toxic (PM(T)) substances by addressing regulatory gaps and promoting circular economy principles. This deliverable, in particular seeks to:

· Identify inconsistencies, gaps, and challenges within the existing EU legal and policy framework related to PM(T) substances.

· Promote harmonized regulatory approaches across environmental compartments.

· Provide EU and national policymakers with actionable, evidence-based policy recommendations to improve the management of PMT(s) in the soil-sediment-water system (and beyond).

· Emphasize that updated policy approaches address disparities and technical, financial and social challenges across Member States (MS).

The "Toolbox Fate & Transport Modelling of PMTs in the Environment" is a key deliverable from the H2020 PROMISCES project. This toolbox is a demonstrator that includes a collection of models developed in the PROMISCES project which are designed to assess the fate and transport of persistent, mobile, and toxic substances (PMTs) across various scales (local, regional) and conditions (e.g., urban run-off, bank filtration, unsaturated zone, groundwater).
This toolbox presents the basic information with links to the software and model input files with which the models can be run. This deliverable is intended for qualified modellers. It is complementary with the Guidance document, deliverable D2.4 (Zessner et al., 2025) which describes how to apply modelling tools in a tiered way as part of predictive risk assessment.

The scope of this document, produced as part of the H2020 PROMISCES project, is to provide guidance for applications of models with a specific focus on model trains for the assessment of exposure to PMTs as part of the predictive risk assessment related to surface and groundwater. This document explains the basic concepts of specific models and how best to use them in model
trains in the framework of a tiered approach. The intention is to inform users and interested stakeholders about what needs to be considered when using different methods, what is the best use of specific models, what are the best combinations in model trains and what are their current limitations.

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.

This model is part of the toolbox built within the framework of the PROMISCES project (Deliverable D2.3).

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.

Release for PROMISCES D 2.3 Toolbox fate & transport modelling

Highlights

• PFAS and other persistent substances found in industrial urban stormwater runoff

• PFOA-equivalent concentrations for PFAS-24 exceeded EU proposal for surface- and groundwater

• Urban stormwater runoff from industrial sites is one source of PFAS in surface waters

Poster presented at the IWA Leading Edge Technologies Conference in Essen, Germany in June 2024