Opinion on Hydroxyapatite (nano)- SCCS/1566/15 – 16 October 2015
Deadline for comments: 8 January 2016
« This opinion has been developed by the SCCS on the basis of a specific set of data submitted by an applicant in order to satisfy specific regulatory requirements. The opinion was approved at a recent plenary meeting and is now open for comments by applicants, national authorities and other interested parties for a period of eight weeks. The intent of the commenting period is to allow applicants and other interested parties to provide additional perspective and/or clarification, if any, about the evaluation, interpretation, and incorporation of the submitted set of data in the SCCS opinion.
Conclusion of the Opinion
1. « In view of above, and taken into account the scientific data provided, the SCCS is requested to give its opinion on the safety of the nanomaterial Hydroxyapatite when used in oral cosmetics products including toothpastes, tooth whiteners and mouth washes with a maximum concentration limit of 10 %, taking into account the reasonably foreseeable exposure conditions.
Only a limited amount of data was provided by the Applicants that corresponded to the SCCS Guidance on Safety Assessment of Nanomaterials in Cosmetics (SCCS 1484/12). The provided data were also not in line with the SCCS Memorandum on Relevance, Adequacy and Quality of Data in Safety Dossiers on Nanomaterials (SCCS/1524/13). To facilitate the assessment, the SCCS therefore also considered additional information gathered through a search of the published scientific literature. However, after detailed evaluation, the SCCS has concluded that the evidence, both that provided in the submission and that available in the scientific literature, is insufficient to allow drawing a conclusion on the safety of nano-hydroxyapatite when used in oral cosmetic products.
This is because:
– The test materials used in toxicological studies lacked information on characterisation, were poorly described, or were different from those under evaluation (Materials 1 and 2). It is not clear in most cases whether and to what extent the investigated materials correspond to the materials under evaluation.
– Almost all of the toxicological studies provided were not compliant with relevant test guidelines in terms of study design. In most cases, study reports included in the submission provided only a poor description of the studies. The quality of the information from scientific publications could not be assessed because detailed study reports were not available.
– No study, either from those provided by the Applicants or obtained from the scientific literature, could be identified that would allow the identification of a point of departure for use in risk assessment.
– Some studies published in the open literature for hydroxyapatite materials, which are different from the materials under evaluation, point to the possibility that nano-hydroxyapatite might be taken up locally (e.g. into buccal cells), and that it might exert systemic effects after oral exposure. Since no information on long-term exposure is available, it is not possible to draw any conclusion on whether repeated, long-term oral exposure to nano-hydroxyapatite would manifest in adverse effects as indicated in the scientific literature (e.g. expressed in Fox et al., 2012).
Based on the information available, SCCS considers that the safety of nano-hydroxyapatite materials included in the submission to the consumer, when used up to a concentration of 10 % in oral cosmetic products, cannot be decided on the basis of the data submitted by the applicants and that retrieved from literature search. Since the available data/ information could not be related to the hydroxyapatite materials under evaluation, the SCCS will need toxicological data specific for the materials included in the submission for safety assessment, unless a close similarity with the materials used in the available studies can be demonstrated to allow data read-across.
Guidance on the types of data important for safety evaluation of nanomaterials in cosmetic products is detailed in the SCCS Nano-Guidance (SCCS/1484/12). Further clarification on certain aspects relating to relevance, adequacy and quality of the data required for safety assessment of nanomaterials is provided in the SCCS Memorandum (SCCS/1524/13).
2. SCCS is requested to address any further scientific concerns with regard to the use of Hydroxyapatite in nano form in cosmetic products.
The available information indicates that nano-hydroxyapatite in needle form is of concern in relation to potential toxicity. Therefore, needle-shaped nano-hydroxyapatite should not be used in cosmetic products. It is of note that Material 2 of the submission is stated by the Applicant to include nano-hydroxyapatite of any shape, which in theory may include needle-like structures. »