Following the mandate given by the European Commission to the SCCS in March 2022, the Scientific Committee has published its final Opinion on the safety of Sodium Bromothymol Blue (C186), a hair dye ingredient. It was adopted at the plenary meeting of 21-22 March 2023, with some modifications compared to the preliminary version.
Background
The ingredient with the INCI name “Sodium Bromothymol Blue” CAS No.34722-90-2, EC No.252-169-7) is a weak acid in solution and thus exists in ionized and non-ionized forms that result in the appearance of different colours. Sodium Bromothymol Blue is intended to be used as a hair dye in non-oxidative hair colouring products with a final on-head concentration up to 0.5%.
The SCCS published its Preliminary Opinion in October 2022, concluding that the safety of Sodium Bromothymol Blue could not be assessed, as the TTC approach used by the applicant did not meet the information requirements for the key toxicological endpoints.
For an exhaustive background information, see the article
• Sodium Bromothymol Blue: request for Opinion to the SCCS, CosmeticOBS, 21 March 2022
• Sodium Bromothymol Blue: preliminary Opinion of the SCCS, CosmeticOBS, 7 November 2022
The SCCS preliminary Opinion has been subject to a commenting period of eight weeks after its initial publication (from 28 October to 23 December 2022). Comments received during this period were considered by the SCCS. For this Opinion, main changes occurred in the following sections: 3.1.5 (SCCS comment and impurity table), 3.1.9, 3.4.2 (NAM + last SCCS comment), respective discussion parts and …
