Revision of the opinion on Titanium Dioxide (nano form)

WG on Nano-materials
SCCS members: U. Bernauer, Q. Chaudhry (chairman and rapporteur), M. Dusinska, W. Lilienblum, Th. Platzek, S. Ch. Rastogi, J. van Benthem
SCENIHR members: P. H. M. Hoet, K. Rydzynski
External experts: O. Bussolati, W. H. de Jong , S. H. Doak, Th. Jung, T. Sanner, N. von Götz
Contact:SANTE-C2-SCCSec [dot] europa [dot] eu (SANTE-C2-SCCS[at]ec[dot]europa[dot]eu)
On request from: European Commission
SCCS Number: SCCS/1516/13
Doi: 10.2772/70108
Adopted on: 22 April 2014

Conclusion of the opinion:

1. Does SCCS consider that use of titanium dioxide in its nanoform as an UV-filter in 23 cosmetic products in a concentration up to maximum 25.0 % is safe for the consumers 24 taken into account the scientific data provided?
On the basis of the available evidence, the SCCS has concluded that the use of TiO2 nanomaterials with the characteristics as indicated below, at a concentration up to 25% as a UV-filter in sunscreens, can be considered to not pose any risk of adverse effects in humans after application on healthy, intact or sunburnt skin. This, however, does not apply to applications that might lead to inhalation exposure to TiO2 nanoparticles (such as powders or sprayable products). Furthermore, this assessment applies to the TiO2 nanoparticles presented in the submission, but may also be applicable to other TiO2 nanomaterials that are similar to the parameters in Tables 1-3, i.e. TiO2 nanomaterials that: (i) have TiO2 purity of ≥99%, or in case of a lesser purity, the impurities must be demonstrated to be safe for use in cosmetic formulations; (ii) are composed of mainly the rutile form, or rutile with up to 5% anatase, with crystalline structure and physical appearance as described in the current submission, i.e. clusters of spherical, needle, or lanceolate shapes; (iii) have a median particle size based on number size distribution of 30 to 100 nm (measured by different methods) as submitted in the dossier, or larger. Thus whilst primary particle size may be smaller (around 10 nm), the median particle size of TiO2 nanomaterials in a cosmetic formulation must not be smaller than 30 nm in terms of number based size distribution; (iv) have an aspect ratio from 1.0 and up to 4.5, and volume specific surface area up to 460 m2/cm3; (v) are coated with one of the coating materials described in Table 1, and the coatings are stable in the final formulation and during use. Other cosmetic ingredients applied as stable coatings on TiO2 nanomaterials can also be used, provided that they can be demonstrated to the SCCS to be safe and the coatings do not affect the particle properties related to behaviour and/or effects, compared to the nanomaterials covered in this opinion. (vi) are photostable in the final formulation; (vii) do not have photocatalytic activity. However, the SCCS considers up to 10% photocatalytic activity compared to corresponding non-coated or non-doped reference as acceptable.
It is also worth highlighting again that this opinion is based on the currently available scientific evidence which shows an overall lack of dermal absorption of TiO2 nanoparticles. If any new evidence emerges in the future to show that the TiO2 nanoparticles used in a sunscreen formulation can penetrate skin (healthy, compromised, or damaged skin) to reach viable cells, then the SCCS may consider revising this assessment.
It should also be noted that the risk assessment of nanomaterials is currently evolving. In particular, the toxicokinetics aspects have not yet been fully explored in the context of nanoparticles (e.g. the size dependency). Also, long term stability of the coatings remains unclear. At the moment, testing of nanomaterials and the present assessment, are both based on the methodologies developed for substances in non-nano form, and the currently available knowledge on properties, behaviour and effects of nanomaterials. This assessment is, therefore, not intended to provide a blue-print for future assessments of other nanomaterials, where depending on the developments in methodological risk assessment approaches and nano-specific testing requirements, additional/different data may be required and/or requested on a case-by-case basis.
It is also important to note that the potential ecotoxicological impacts of nano TiO2 when released into the environment have not been considered in this opinion.
2. In order for the COM to differentiate in the regulation between materials in its nanoform and its non-nano form, can the SCCS give quantitative and qualitative guidance on how this differentiation should be given based on the particle size distribution or other parameters? A detailed SCCS guidance on risk assessment of nanomaterials in cosmetics has recently been published (SCCS/1484/12). The guidance provides a detailed account of the important nano-related parameters that should be considered in relation to physicochemical characterisation, hazard identification, exposure assessment and risk assessment of nanomaterials.

Keywords:

SCCS, scientific opinion, UV filter, titanium dioxide (nano form), SCCS/1516/13, directive 76/768/ECC, CAS number: 13463-67-7, EC: 236-675-5

Opinion to be cited as:

SCCS (Scientific Committee on Consumer Safety), Opinion on titanium dioxide (nano form), 22 July 2013, revision of 22 April 2014.