In Europe, the Scientific Committee on Consumer Products (SCCP) has been busy reviewing the components of hair dyes. On Dec. 13, 2005, the committee issued its opinion on the exposure and reaction products of oxidative hair dye formulations. For chemists interested in the chemistry of oxidative hair dyes, this is an excellent review of the various chemical reactions that result in hair dyeing.
Table 1 lists the hair dye components that are being reviewed and the deadlines for submission of safety dossiers. Obviously, it is a major effort to review all of these components. It is taking the SCCP’s time and delaying the committee’s work in other areas. With luck this task will be concluded by the end of this year, which is the committee’s timetable.
The SCCP is reviewing the following chemicals: toluene, cyclotetrasiloxane (D4 cyclomethicone), zinc oxide and diethylamino hydroxybenzoyl hexyl benzoate.
Toluene and cyclotetrasiloxane are being reviewed because they are Category 3 CMRs, which are materials believed to be carcinogenic, mutagenic or toxic to reproduction. Before they can be used, they must be listed by the SCCP in Annex III. In addition, their percentages in any fi nished product must be disclosed to the consumer, as required by the Seventh Amendment to the Cosmetic Directive. This leads to a complex issue: if the product label lists the term cyclomethicone instead of the actual INCI names cyclotetrasiloxane, cyclopentasiloxane or cyclohexasiloxane, the manufacturer could be required to show the cyclotetrasiloxane content even though there is none. (See Annexes of the EU’s Cosmetic Directive.