Nanotechnology is one of the most exciting areas of modern science, already bringing innovations across clean energy production, defence and security, bio-engineering to convert waste into usable materials, medical treatments, more efficient transport, personal care and much more. In cosmetics, nanomaterials are used in carefully formulated products that provide practical benefits for consumers, such as improved sunscreen performance and smoother, lighter product textures.
What is a nanomaterial?
A nanomaterial is a very small substance. It that has one or more dimensions between 1 and 100 nanometres. To put that into perspective, a typical bacteria cell is around 1,000 nanometres wide and a human hair is about 80,000 nanometres across. Nature itself is full of nanostructures: milk is a natural nanoemulsion, and proteins can exist as nanoparticles.
In cosmetics, nanomaterials can be found in both natural and synthetically manufactured forms. What matters most is the size, stability, and behaviour of the material. Commonly used nanomaterials in cosmetics include:
- Titanium dioxide (TiO2): Used in sunscreens to reflect UV light. In its nano form, it becomes transparent and easier to spread, while maintaining strong UV protection.
- Carbon black: A colourant that becomes more intense and consistent when used in nano form.
Other materials such as zinc oxide or iron oxides can also be used in nano form. All nanomaterials used in cosmetics must meet strict safety criteria.
Nanoemulsions and nanosomes (tiny structures used to deliver ingredients) are not classified as nanomaterials under UK and EU cosmetics law because they are soluble and disintegrate on contact with the skin.
Can nanoparticles penetrate the skin?
The skin is relatively impermeable to nanomaterials because the outer layer of skin acts as an effective barrier. Whether a substance can penetrate the skin depends on a number of factors such as its size, its structure and its chemical properties. Nano sunscreen ingredients, such as nano titanium dioxide, are designed to stay on the surface to protect from UV damage. If they penetrated the skin, they wouldn’t work effectively as sunscreens.
Are nanomaterials safe?
Yes. All cosmetic ingredients, including nanomaterials, must undergo a thorough safety assessment before being used in products sold in the UK. These assessments are carried out by qualified safety assessors under strict laws. The safety of nanomaterials is reviewed case by case and includes data on the specific form used, how it behaves, and how it might be absorbed.
Titanium dioxide, for example, is one of the most extensively studied ingredients in cosmetic science. Nanotechnology itself is continuously monitored by global regulatory authorities to ensure that products are safe for consumer use.
How can I tell if a product contains nanomaterials?
If a cosmetic ingredient is classed as a nanomaterial, it must be clearly labelled. You will see the word "nano" in brackets after the ingredient name in the list on the packaging. For example, "Titanium Dioxide (nano)". This transparency allows consumers to make informed choices. However, not all forms of ingredients like titanium dioxide are nano-sized. Non-nano versions used in products will not carry the (nano) label.
Responsible innovation and regulation
Nanomaterials offer benefits in formulation, feel, and performance of cosmetics, especially sunscreens. The cosmetics industry works closely with scientists and regulators to ensure that all nano-ingredients are thoroughly tested, regulated, and clearly labelled.
You can find out more from reputable sources such as the European Commission’s page on nanomaterials in cosmetics.
Nanotechnology in cosmetics is just one example of how science and regulation work together to deliver safe, effective, and innovative products.
