Methylchloroisothiazolinone (MCIT) and Methylisothiazolinone (MIT) are preservatives often used in cosmetics, in any kind of product. Though allowed and restricted in concentration in formulae, they are regularly questioned, especially when used as mixture, about their potential sensitizing effect. The European Commission envisages restricting their use as mixture to rinse-off products only. A public consultation is open until 8 October 2013.
Text of the public consultation on Methylchloroisothiazolinone and Methylisothiazolinone in the frame of the Regulation (EC) nbr 1223/2009
Background
Methylchloroisothiazolinone and Methylisothiazolinone with magnesium chloride and magnesium nitrate (INCI) is currently regulated as a preservative in the Cosmetics Regulation in Annex V, entry 39 with the maximum authorized concentration 0.0015% (15 ppm) of a mixture in the ratio 3:1 of 5-chloro-2-methylisothiazolin-3(2H)-one and 2-methylisothiazolin-3(2H)-one. Methylisothiazolinone is also allowed on its own in entry 57.
Following the submission of a fully updated dossier by the industry in 2006, the SCCS adopted an opinion in 2009, in which it concluded the following:
"On the basis of the data submitted, the SCCS is of the opinion that the mixture of 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one in a ratio of 3:1 does not pose a risk to the health of the consumer when used as a preservative up to a maximum authorized concentration of 0.0015 % in rinse-off cosmetic products, apart from its sensitizing potential."
In light of the scientific opinion (SCCS/1238/09), the Commission proposes to restrict the use of this mixture to rinse-off products.
The issue of stabilizers for this mixture was addressed in opinion SCCNFP/0670/03, final. The Committee stated that "taking into account that the …