The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to consider evaluations of flavouring substances assessed since 2000 by the Joint FAO/WHO Expert Committee on Food Additives (the JECFA), and to decide whether further evaluation is necessary, as laid down in Commission Regulation (EC) No 1565/2000. The present consideration concerns a group of five sulphur-containing heterocyclic compounds [FL-no: 15.010, 15.126, 15.128, 15.130 and 15.131] evaluated by the JECFA at its 68th meeting in 2007. This revision is required owing to additional available genotoxicity data on 2-acetyl-2-thiazoline [FL-no: 15.010]. Since the publication of FGE.93, the substance [FL-no: FL-no: 15.127] is no longer supported by Industry for use as a flavouring substance in Europe and will therefore not be considered any further. The substances were evaluated through a stepwise approach that integrates information on structure-activity relationships, intake from current uses, toxicological threshold of concern, and available data on metabolism and toxicity. The two substances 5-ethyl-4-methyl-2-(2-methylpropyl)-thiazoline [FL-no: 15.130] and 5-ethyl-4-methyl-2-(2-butyl)-thiazoline [FL-no: 15.131], which are 3-thiazolines, are structural similar to two other 3-thiazolines in FGE.21Rev1 for which the Panel has expressed a genotoxicity concern, and accordingly the Procedure should not be applied to these two substances until adequate genotoxicity data become available. The Panel agrees with the application of the Procedure as performed by the JECFA for the remaining three substances, 2-acetyl-2-thiazoline [FL-no: 15.010], 3-(methylthio)-methylthiophene [FL-no: 15.126] and 2-propionyl-2-thiazoline [FL-no: 15.128], of the five substances considered in this FGE and agrees with the JECFA conclusion, “No safety concern at estimated levels of intake as flavouring substances” based on the MSDI approach. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been considered and for all five substances, the information is adequate.