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Sunscreens with Titanium Dioxide As Nanoparticles Health Risks?

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Sunscreens with Titanium Dioxide As Nanoparticles Health Risks? Sunscreens with titanium dioxide as nanoparticles Health risks? The increasing use of cosmetic products may not show this nanoparticles do not remain photocatalysts of nanomaterials concentration on the package, but manufacturers but still retain their function as a UV filter. in a wide range of have to respect this limit according to European Nevertheless, sunscreen manufacturers consumer prod- legislation (annex III of the EU regulation on are recommended to avoid the use of ucts has prompt- cosmetic products; regulation EC 1223/2009). titanium dioxide nanoparticles that have ed a re-evalua- Inspectors from public authorities can perform a a substantial photocatalytic activity, or to tion of the safety check at any time. treat the surface of such nanoparticles of a number of The safety assessment is based on the current properly with a stable and safe coating substances, scientific knowledge, which shows that neither material. including tita- titanium dioxide in nano form nor in non-nano NEW CHALLENGES IN RISK nium dioxide form penetrates through the skin. This conclusion ASSESSMENT OF NANOMATERIALS (TiO ). Tita- will need to be revised if new scientific evidence 2 would arise, showing that nanoparticles behave nium dioxide, in This opinion refers to the titanium dioxide differently. the form of nanoparticles used materials revised by the SCCS and to to render creams and lotions transparent, is SAFE, BUT . materials with similar characteristics currently approved as a UV-filter in sunscreens. of size, purity, coating and solubility. As Are sunscreens with titanium dioxide nano- Breathing in nanoparticles can lead to lung the methodologies for evaluating the particles safe? Do these nanoparticles behave toxicity and inflammation. Some tests suggest properties of nanomaterials in general are differently than other particles of titanium di- that this could also lead to cancer. In view of still in development, additional data may oxide? How are the risks of nanoparticles eval- this, the SCCS advises not using titanium dioxide be required for a full assessment of the uated? This fact sheet tells you all about it. nanoparticles in applications that would lead health impact of titanium dioxide in nano to any significant inhalation exposure such as form. The development of new assessment WHAT ARE ‘NANOMATERIALS’? WHAT ARE powders or sprayable products. methods is an ongoing process. TITANIUM DIOXIDE NANOPARTICLES? There is also a very low risk for skin or eye irritation (painful reaction such as eczema with The SCCS published detailed guidance Titanium dioxide is used as a UV filter in sunscreen dry itchy skin) and skin sensitisation (response documents on the evaluation of risks of products to protect the skin from harmful of the immune system resulting in an allergic nanomaterials in cosmetics (SCCS/1484/12 UV rays when exposed to sunlight. Particles reaction) from exposure to these nanomaterials. and SCCS/1524/13). in nano form (also named ‘nanomaterials’, No relevant information on reproductive toxicity ‘nanoparticles’ or ‘micronized materials’) refer is yet available, but some scientific evidence For completeness, it should be noted to very small sized materials and components suggests that titanium dioxide nanomaterials, that the impact of titanium dioxide that have a particle size range of 1 to 100 if they penetrate the body, may cause damage nanoparticles released in the environment nanometre (one nanometre is one millionth of to genetic material of cells (e.g. damage to cells was not considered in this scientific opinion. a millimetre, e.g. human hair is about 80 000 in some organs may cause cancer and damage nanometres wide). Very small particles may, to spermatozoa cells may lead to infertility). however, also be harmful (see further). However, such effects are unlikely to occur with This fact sheet is based on the IS THE USE OF TITANIUM DIOXIDE dermal application. opinion of the independent Scientific NANOPARTICLES IN SUNSCREENS SAFE? Titanium dioxide nanoparticles can also act, in Committee on Consumer Safety certain cases, as a photocatalyst. This means (SCCS): ‘Opinion on titanium dioxide On the basis of the available scientific evidence, that they can react with UV light (e.g. sun) to (nano form) COLIPA n° S75’ (April 2014). the Scientific Committee on Consumer Safety accelerate a photoreaction causing oxidation (SCCS) confirmed that the evaluated titanium of some biological molecules and generating dioxide nanoparticles, used at a concentration free radicals. The latter could enhance the This opinion is available at: up to 25% as a UV filter in sunscreens, can be toxic effects mentioned above. Not all titanium http://ec.europa.eu/health/scientific_ considered safe for humans after application dioxide particles used in cosmetic products have committees/consumer_safety/ on a healthy, intact or sunburnt skin. Labelling this property. When appropriately coated, the opinions/index_en.htm Health and Consumers.
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