Genotoxicity assessment of chemical mixtures

genotoxicity assessment, chemical mixtures, uncertainty analysis
First published in the EFSA Journal
16. Januar 2019
Adopted
22. November 2018
Type
Statement

Abstract

The EFSA Scientific Committee addressed in this document the peculiarities related to the genotoxicity assessment of chemical mixtures. The EFSA Scientific Committee suggests that first a mixture should be chemically characterised as far as possible. Although the characterisation of mixtures is relevant also for other toxicity aspects, it is particularly significant for the assessment of genotoxicity. If a mixture contains one or more chemical substances that are individually assessed to be genotoxic in vivo via a relevant route of administration, the mixture raises concern for genotoxicity. If a fully chemically defined mixture does not contain genotoxic chemical substances, the mixture is of no concern with respect to genotoxicity. If a mixture contains a fraction of chemical substances that have not been chemically identified, experimental testing of the unidentified fraction should be considered as the first option or, if this is not feasible, testing of the whole mixture should be undertaken. If testing of these fraction(s) or of the whole mixture in an adequately performed set of in vitro assays provides clearly negative results, the mixture does not raise concern for genotoxicity. If in vitro testing provides one or more positive results, an in vivo follow‐up study should be considered. For negative results in the in vivofollow‐up test(s), the possible limitations of in vivo testing should be weighed in an uncertainty analysis before reaching a conclusion of no concern with respect to genotoxicity. For positive results in the in vivo follow‐up test(s), it can be concluded that the mixture does raise a concern about genotoxicity.

Panel members at the time of adoption

Simon More, Vasileios Bampidis, Jos Boesten, Diane Benford, Claude Bragard, Thorhallur Halldorsson, Antonio Hernandez‐Jerez, Susanne Hougaard‐Bennekou, Kostas Koutsoumanis, Søren Saxmose Nielsen, Hanspeter Naegeli, Josef Schlatter, Dieter Schrenk, Vittorio Silano, Dominique Turck, Maged Younes.
Contact
sc.secretrariat [at] efsa.europa.eu
doi
10.2903/j.efsa.2019.5519
EFSA Journal 2019;17(1):5519
Question Number
On request from
Scientific Committee