Workshop on read-across: role and guidance in chemical risk assessment

27 March 2025, 13.30 - 17.30 (CET)

28 March 2025, 09.00 - 13.00 (CET)

Brussels, Belgium

Registration available soon

Background

Read-across is an approach used in chemical risk assessment for screening, classification, prioritisation and hazard assessment of substances, based on toxicological data of similar chemicals. It is meant to complement and inform the risk assessment, e.g. to provide supporting evidence that must be seen as part of the overall weight of evidence (WoE). The process includes the use of known information from one or more (data-rich) source substances to predict the same property for a (data-poor) target substance, and it is one of the most common alternatives to animal testing for filling data gaps.

The practical steps for developing a category and analogue approach have been previously established. The read-across approach outlined in the OECD guidance documents (OECD 2007, with revisions in 2014 and 2024), as well as ECHA’s Guidance (2008) and Framework (2017) developed in the context of information requirements under REACH regulation, have been applied and modified for use in various other domains. In addition, ECHA is currently working on a practical guide for the application of grouping and read-across under Classification, Labelling and Packaging (CLP).

In this context, EFSA’s Scientific Committee identified a similar need within its remit and is developing guidance on the use of read-across in food and feed risk assessment. The draft guidance is available for public consultation from 10 March to 21 April 2025

Objectives of the workshop

The first objective of the workshop is to examine regulatory approaches on read-across that have been developed and implemented by different organisations, supporting further the alignment of methodologies applied in chemical risk assessment.

The second objective is to discuss and clarify technical aspects of read-across, and to receive feedback on the related draft guidance developed by EFSA.
Overall, the workshop aims to contribute to strengthening a robust, scientifically sound and transparent application of read-across in chemical risk assessment across organisations.

Description of the workshop sessions

Session 1 – Existing guidance and frameworks, and the role of read-across in chemical risk assessment

This session will initially be dedicated to a general introduction to the read-across approach, followed by presentations on guidance documents in this area from OECD, ECHA and EFSA. These will be followed by a discussion and an exchange of views on the role of read-across in the risk assessment process and as part of the WoE approach. The discussion aims to further support the implementation of the approach, but also to identify challenges, similarities and possible divergences between approaches, e.g. due to different contexts of use or the framework under which they are applied.
The session will also allow participants to further clarify aspects related to the context of use and degree of obligation for the guidance documents of different organisations.

Session 2 – Technical aspects of the read-across approach

This session will address technical aspects and clarifications regarding the steps of the read-across approach. It will specifically address EFSA's draft guidance and provide potential users with a better understanding of some of the technical and scientific aspects.
During the session, EFSA’s Working Group on read-across will explain details of the read-across steps, along with representative examples, and respond to questions from participants.

Who should attend?

The event is intended for all interested stakeholders, especially risk assessors and applicants (e.g. members of EFSA and ECHA panels, working groups and staff, representatives of EU, national and international agencies, industry, academia and research organisations). Participation is limited to a maximum of 60 attendees, including speakers and other experts. Pre-selection will ensure an appropriate representation of the various fields of expertise, as well as representation of stakeholder groups and geographical balance.