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Scientific Committee on Consumer Safety SCCS SCCS/1489/12 Revision of 11 December 2012 Scientific Committee on Consumer Safety SCCS OPINION ON Zinc oxide (nano form) COLIPA S 76 The SCCS adopted this opinion at its 16th plenary meeting of 18 September 2012 SCCS/1489/12 Opinion on zinc oxide (nano form) ___________________________________________________________________________________________ About the Scientific Committees Three independent non-food Scientific Committees provide the Commission with the scientific advice it needs when preparing policy and proposals relating to consumer safety, public health and the environment. The Committees also draw the Commission's attention to the new or emerging problems which may pose an actual or potential threat. They are: the Scientific Committee on Consumer Safety (SCCS), the Scientific Committee on Health and Environmental Risks (SCHER) and the Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) and are made up of external experts. In addition, the Commission relies upon the work of the European Food Safety Authority (EFSA), the European Medicines Agency (EMA), the European Centre for Disease prevention and Control (ECDC) and the European Chemicals Agency (ECHA). SCCS The Committee shall provide opinions on questions concerning all types of health and safety risks (notably chemical, biological, mechanical and other physical risks) of non-food consumer products (for example: cosmetic products and their ingredients, toys, textiles, clothing, personal care and household products such as detergents, etc.) and services (for example: tattooing, artificial sun tanning, etc.). Scientific Committee members Jürgen Angerer, Ulrike Bernauer, Claire Chambers, Qasim Chaudhry, Gisela Degen, Elsa Nielsen, Thomas Platzek, Suresh Chandra Rastogi, Vera Rogiers, Christophe Rousselle, Tore Sanner, Jan van Benthem, Jacqueline van Engelen, Maria Pilar Vinardell, Rosemary Waring, Ian R. White. Contact European Commission Health & Consumers Directorate D: Health Systems and Products Unit D3 - Risk Assessment Office: B232 B-1049 Brussels [email protected] © European Union, 2012 ISSN 1831-4767 ISBN 978-92-79-30777-5 Doi:10.2772/88660 ND-AQ-12-027-EN-N The opinions of the Scientific Committees present the views of the independent scientists who are members of the committees. They do not necessarily reflect the views of the European Commission. The opinions are published by the European Commission in their original language only. http://ec.europa.eu/health/scientific_committees/consumer_safety/index_en.htm 2 SCCS/1489/12 Opinion on zinc oxide (nano form) ___________________________________________________________________________________________ ACKNOWLEDGMENTS SCCS members Dr. Q. Chaudhry (chairman) Prof. T. Sanner Dr. J. van Engelen SCENIHR members Prof. K. Dawson Dr. W. de Jong (rapporteur) Prof. P. Hoet Dr. T. Jung External experts Dr. W. Kreyling, Helmholtz Zentrum München, Germany Dr. R. Schins, IUF - Leibniz Research Institut für umweltmedizinische Forschung, Germany Keywords: SCCS, scientific opinion, ZnO (nano form), directive 76/768/ECC, CAS 1314-13- 2, EC 215-222-5 Opinion to be cited as: SCCS (Scientific Committee on Consumer Safety), Opinion on ZnO (nano form), 18 September 2012 This opinion has been subject to a commenting period of four weeks after its initial publication. Comments received during this time have been considered by the SCCS and discussed in the subsequent plenary meeting. Where appropriate, the text of the relevant sections of the opinion has been modified or explanations have been added. In the cases where the SCCS after consideration and discussion of the comments, has decided to maintain its initial views, the opinion (or the section concerned) has remained unchanged. Revised opinions carry the date of revision. 3 SCCS/1489/12 Opinion on zinc oxide (nano form) ___________________________________________________________________________________________ TABLE OF CONTENTS 1. BACKGROUND ............................................................................................. 5 2. TERMS OF REFERENCE.................................................................................. 6 3. OPINION..................................................................................................... 7 3.1 Chemical and physical specifications ....................................................... 7 3.1.1 Chemical identity.................................................................... 7 3.1.2 Physical form ......................................................................... 8 3.1.3 Molecular weight .................................................................... 8 3.1.4 Purity, composition and substance codes.................................... 9 3.1.5 Impurities/accompanying contaminants ..................................... 9 3.1.6 Solubility ............................................................................... 9 3.1.7 Partition coefficient (Log Pow).................................................. 11 3.1.8 Additional physical and chemical specifications.......................... 11 3.1.9 Particle size ......................................................................... 12 3.1.10 Microscopy .......................................................................... 15 3.1.11 Crystal structures ................................................................. 17 3.1.12 UV absorption ...................................................................... 18 3.1.13 Zeta potential ...................................................................... 21 3.1.14 Droplet size in formulations.................................................... 22 3.1.15 Homogeneity and stability...................................................... 25 3.1.16 Summary on supplementary physicochemical characterization .... 26 3.2 Function and uses.............................................................................. 27 3.3 Toxicological evaluation ...................................................................... 27 3.3.1 Acute toxicity ....................................................................... 27 3.3.2 Irritation and corrosivity ........................................................ 32 3.3.3 Skin sensitization.................................................................. 37 3.3.4 Dermal/percutaneous absorption ............................................ 40 3.3.5 Repeated dose toxicity .......................................................... 55 3.3.6 Mutagenicity/genotoxicity ...................................................... 59 3.3.7 Carcinogenicity..................................................................... 68 3.3.8 Reproductive toxicity............................................................. 68 3.3.9 Toxicokinetics ...................................................................... 68 3.3.10 Photo-induced toxicity ........................................................... 69 3.3.11 Human data......................................................................... 79 3.3.12 Special investigations ............................................................ 82 3.3.13 Safety evaluation (including calculation of the MoS)................... 88 3.3.14 Discussion ........................................................................... 91 4. CONCLUSION ............................................................................................ 95 5. MINORITY OPINION.................................................................................... 98 6. REFERENCES............................................................................................. 98 4 SCCS/1489/12 Opinion on zinc oxide (nano form) ___________________________________________________________________________________________ 1. BACKGROUND Zinc oxide (CAS No. 1314-13-2; EC No. 215-222-5) has widespread use in cosmetic products with the following functions: bulking, skin protection and as a UV absorber, besides its authorized use in all cosmetics as a cosmetic colorant with the Colour Index No. CI 77947 in Annex IV. Two former submissions on zinc oxide in pigmentary form as well as in the form of a nanomaterial were submitted in order to have zinc oxide approved as a UV-filter in cosmetic sunscreen products at a maximum level of 25%. The first scientific opinion (SCCNFP/0649/03, final) on zinc oxide was adopted by the SCCNFP during its 24th plenary meeting of 24-25th June 2003 with the following conclusion: "A considerable part of the investigations and their results submitted have been performed 15 or more years ago and consequently cannot fulfil modern requirements. However, there 2+ is a broad basic knowledge on Zn and its compounds, e.g. ZnO. The physicochemical specifications of ZnO used in many of the studies are incomplete, the purity/impurities not specified. On the other hand, ZnO is practically insoluble in water. Thus, in general, ZnO may be considered as a non-toxic substance, including when used in cosmetic products. The main concern of the present evaluation is related to the risk assessment of micronized (approximately 0.2 μm) ZnO, which may be coated by other compounds, and which is used as an ingredient in sunscreen formulations. Micronized ZnO has been demonstrated to be photoclastogenic, possibly photo-aneugenic, and a photo-DNA damaging agent in mammalian cells cultured in vitro. The relevance of these findings needs to be clarified by appropriate investigations in vivo. There is a lack of reliable data on the percutaneous absorption
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