A “Memorandum on hair dye substances and their sensitising properties” adopted during the 10th Plenary of the SCCP on 19 December 2006, summarised the evaluation on the 48 hair dye substances that had been assessed by the SCCP at that time. 27 of the dyes were noted to fulfil the EU criteria for classification as skin sensitizers (R43). Additionally, 10 of the 27 classifiable hair dye substances were categorised as extreme sensitizers, 13 as strong and 4 as moderate sensitizers.

The SCCP stated that hair dye substances which fulfil the criteria for classification as R43 may not be safe for consumers and that this is particularly so for hair dye substances categorised as extreme and strong sensitizers.

It was necessary to write the Memorandum as the assessment of the safety of hair dyes has been in terms of general toxicology rather than sensitization potential. Hence, “hair dye chemical X is safe for use at Y% in hair dyes intended for the consumer apart from its potential to cause skin sensitization”.

The response to the above Memorandum by the European Commission (29 March 07) was:

1. The Commission services will now extend their assessment in order to minimise possible risks of allergic reactions caused by hair dyes.
2. Epidemiological studies are necessary to examine the extent of skin allergies to hair dyes in the EU’s population.
3. Threshold values for sensitisers of high concern need to be determined to take appropriate measure on a possible decrease of exposure.