Glyphosate is an active substance used in many herbicides. In December 2017, the European Union re-approved its use for a further five years. As part of the national glyphosate withdrawal plan designed to phase out its main uses by the end of 2020, ANSES is carrying out a series of studies on this active substance and the products containing it.
Following the controversy on the carcinogenic classification of glyphosate, ANSES was asked to draw up specifications for one or more toxicology studies in order to improve knowledge of the substance’s carcinogenic potential.
Studies based on an integrated approach
ANSES set up an expert group of toxicologists specialising in genotoxicity and carcinogenesis to define research specifications on the basis of available assessments and the data recorded in the literature. Following this expert appraisal, the Agency proposes an integrated approach to better understand the possible carcinogenic (genotoxic or epigenetic) mechanisms of action of glyphosate and to assess their relevance for humans.
ANSES thus recommends the following studies:
- in vitro tests to study the effects on human and animal cells that could be related to cellular stress following exposure to glyphosate. These tests could identify the molecular pathways involved in the cellular response. The results will help interpret the other recommended tests and explain the conflicting results observed in the literature.
- an in vivo comet assay in rats and mice (stomach, intestine, liver, kidney and pancreas), coupled with a micronucleus assay. These tests, which measure DNA damage, should clarify the genotoxic potential of glyphosate. The results will complement studies already available, including those conducted by the US National Toxicology Program.
- acell transformation assay coupled with the "Transformics" method using transcriptomics (study and analysis of genome transcription). These tests could identify in vitro glyphosate’s possible carcinogenic modes and mechanisms of action.
These studies should be conducted by independent research teams under strict conditions of experimentation and traceability. The results must be available by the end of 2021 at the latest for submission as part of glyphosate’s re-approval process.
A public call for applications will be posted on the ANSES website in July 2019. A transparent selection procedure will be implemented by the Agency, particular attention being paid to compliance with ethical rules.