The European Food Safety Authority (EFSA) was asked by the European Commission, in accordance with Article 31 of Regulation (EC) No 178/2002, to assess a recent publication on the possible effect of diacetyl [FL-No 07.052] in enhancing β-amyloid-induced neurotoxicity, and to verify whether these additional data are of concern for the safe use of diacetyl as a flavouring substance in food. In the scientific paper the authors conclude that industry workers exposed chronically via inhalation to diacetyl could possibly develop neurological symptoms related to diacetyl exposure. EFSA has evaluated the paper in relation to the potential risk of the use of diacetyl [FL-No 07.052] as flavouring agent in food. EFSA's evaluation concluded that the cytotoxicity assay and the cellular system used by the authors have shortcomings that did not allow the extrapolation of the data to be used in the safe assessment of diacetyl as a flavouring agent in food. Additionally, the authors have not provided any correlation between occupational exposure and systemic exposure. Based on these considerations, EFSA concluded that the information in scientific paper does not bring any new scientific elements for the safe use of diacetyl in food.