Streamlining models and tools for release, fate and exposure assessment of NFs/NEPs for Safe by Design (SbD) purposes

Poster Background, Motivation and Objective: There is a need to improve the usability of models and tools for the release, fate and exposure assessment of nanoforms (NF) and nano-enabled products (NEPs) throughout the life cycle and for these considerations to be taken into account at an early stage of the innovation process for SbD. Within the EU Horizon 2020 SAbyNA project, we have distilled elements from identified exposure tools and models for occupational, consumer and environmental exposure and identified potential improvements for these tools and models to serve for SbD purposes. Work is ongoing on improving exposure tools and models for SbD with a focus on the GUIDEnano tool tailoring to the needs of stakeholders, particularly SMEs. Statement of Contribution/Methods: This assessment has been split into two parts: 1) Environmental release and fate tools and models and 2) Human exposure models and tools. The tools and models to be assessed were first selected using defined criteria (such as inhalation exposure in occupational settings and consumers, dermal exposure, qualitative/quantitative models for human exposure and “ready to use” and nano-specific for environmental exposure). For those tools and models, which met the criteria (17 for environmental release and fate and eleven for human exposure), key elements of these were distilled (i.e. such as expertise required, assumptions, input parameters, inter-user variability, algorithms and uncertainty analysis). Following this distillation process, a shortlist of tools and models for further consideration for SbD has been compiled. Results/Discussion: Seven environmental exposure models and three release and grouping models were shortlisted after distillation. It was concluded that none of the shortlisted models were ideally suited for SbD purposes, with GUIDEnano the most promising. A number of aspects have been highlighted for environmental exposure models including improving model accessibility, creating theoretical scenarios for geographical considerations for SbD, improving run times of models, the scope for including default parameters and uncertainty and sensitivity analysis which is generally lacking. The provision of release rates to environmental exposure models is a key driver of uncertainty, which, in the absence of more detailed release data, can be helped by the use of Specific Environmental Release Categories (SPERCs). For human exposure, nine models and tools were shortlisted after distillation. As for the case for environmental exposure, GUIDEnano is the most promising tool for SbD. Aspects highlighted from the analysis for the tools and models include potential improvements in model assumptions, input parameters (such as identifying minimum parameters required), inter-user variability (which was observed) and improvements to uncertainty analysis. For uncertainty evaluation, further work has been undertaken on the Precautionary Matrix with a flowchart and a Standard Operating Procedure produced for uncertainty analysis in human exposure models. The current focus of our work is on improving the aspects identified (i.e. assumptions, input parameters, algorithms and uncertainty) of the environmental fate and human exposure modules of GUIDEnano, to be used for SbD purposes. An update of this work will be presented, including the development of user-friendly pre-defined activities that can be used independently or as a cascade of activity for paints and 3D printing. Funding information SAbyNA has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 862419