Search

New Approach Methodologies (NAMs), broadly understood to include in silico, in chemico, in vitro and ex vivo methods, show great potential in advancing risk assessment albeit their regulatory implementation is lagging. The EFSA Guidance on risk assessment of nanomaterials (EFSA Guidance on Nano‐RA) suggests nano‐specific risk assessment is best achieved through Integrated Approaches to Testing and Assessment (IATAs) with NAMs as the first choice to generate new information. Integrating NAMs in risk assessment promises several advantages such as a better human focus, more detailed insights into molecular mechanisms and a higher efficacy. However, applying NAMs to NMs also poses considerable challenges such as issues related to dispersion stability, dosimetry, agglomeration, dissolution, transformations or assay interferences. Significant efforts are being undertaken by standardisation organisations and research projects to establish various NAMs for NMs. Here a thorough review is provided covering NAMs that will be potentially useful for risk assessment of NMs in the food and feed sector. It follows the structure of the EFSA Guidance on Nano‐RA and expands it, where needed, to support decision‐making in selection of NAMs for NM risk assessment. The review begins with an overview on nano‐specific NAM‐frameworks, followed by a description of individual NAMs including those relevant to NM physicochemical characterisation, exposure and hazard assessment covering toxicodynamics and toxicokinetics. The focus is on NAMs concerning NM degradation/dissolution, genotoxicity, cytotoxicity, oxidative stress, (pro‐)inflammation, and barrier integrity as those are important endpoints for initial screening according to the EFSA framework. As a result, in total 267 individual nano‐relevant NAMs, mostly "not validated" (with a few notable exceptions), were included in this review. Validation notwithstanding, NAMs could already prove relevant and reliable for risk assessment of NMs, especially in integrated approaches. [ABSTRACT FROM AUTHOR]

Plenty of new approach methodologies (NAMs) for risk assessment have been developed but only some are included in OECD Test Guidelines (TGs) for regulatory implementation. Nevertheless, NAMs are increasingly applied, e.g. for nanomaterial (NM) risk assessments. The EFSA Guidance on NM risk assessment suggests that NAM‐derived data concerning degradation/dissolution (in relevant biofluids), intestinal uptake/crossing, genotoxicity, cytotoxicity, oxidative stress, (pro‐)inflammatory potential and barrier integrity, for many of which no OECD TGs exist, have to be evaluated first. Consequently, NM risk assessments involve data from non‐guideline studies, requiring time‐consuming and challenging case‐by‐case evaluations. Establishing an OECD TG is a formal process aiming for international use according to the Mutual Acceptance of Data (MAD). However, not every promising NAM can be prioritised for OECD TGs. A qualification, based on an expert opinion, may enable an efficient use of adequate NAMs for a specific context‐of‐use. Furthermore, it supports the optimisation of promising NAMs for regulatory applications. Existing qualification systems operate in the context of e.g., drug development tools (FDA) and research and development into pharmaceuticals (EMA). The NAMS4NANO consortium was tasked to propose a generic framework for a qualification system for chemical risk assessment in the food and feed sector to speed up the regulatory use of NAMs. Here we describe our proposal including the process and evaluation criteria. A detailed test method description, preferably as standard operating procedures (SOPs), describing the set‐up of the NAM including its application and evaluation phase is crucial. Furthermore, the scientific validity, i.e. its reliability and relevance for the context‐of‐use, needs to be demonstrated, for which we suggest a less rigorous process compared to OECD TGs. We propose to initially establish a qualification system for NM risk assessment, aligned with the EFSA framework. This document is an interim version to stipulate a broader discussion among experts and stakeholders. [ABSTRACT FROM AUTHOR]