In response to the questions asked, the SCCP is of the opinion that for practical reasons, the following concentration limits of hydrogen peroxide, when used in oral hygiene and tooth whitening products, should be considered: up to 0.1%, up to 6% (Higher concentrations may be used provided that the total amount of hydrogen peroxide is equal or lower than in products using 6% hydrogen peroxide and 0.2 g gel load and that studies have demonstrated that the concentration of hydrogen peroxide in the saliva and on the gingiva is not higher than in products containing 6% hydrogen peroxide), and more than 6%. The limit of 0.1% is based on a level at which there is no risk to the consumer from the use of hydrogen peroxide in oral hygiene and tooth whitening products under normal or reasonable foreseeable conditions of use. In toothpastes and mouth rinses, the hydrogen peroxide concentration should not exceed 0.1% (SCCNFP/0158/99). The limit of 6% for tooth whitening products refers to the limit given in the Terms of Reference in relation to the Opinion SCCP/0844/04. It should also be noted that for hydrogen peroxide concentrations above 6%, the MOS will be below 100; therefore, products containing more than 6% hydrogen peroxide are not safe for use by the consumer.
The present opinion refers to the concentration of hydrogen peroxide in its free form or when released (some hydrogen peroxide releasing substances may not be specifically mentioned in this opinion). In the case of the substances discussed in Appendix (sodium percarbonate, sodium perborate, and potassium peroxymonosulphate), it refers to the concentrations of the substances that will result in the same amount of hydrogen peroxide or reactive oxygen species being available as the specified concentrations of hydrogen peroxide above.