Nanotechnology is a multidisciplinary field that is getting wider as the days pass. ‘Nano’ has become a part of our everyday life that started from information technology and spreads fast to cosmetics. ‘Nano’ has come very close to us as we apply these nanoparticles on our skin. But the nanoparticles in our daily cosmetics are safe, right? It is not easy to say if nanoparticles in general are safe or not. There are just too many details for the average consumer to understand thoroughly. I tried to find out what is the difference between a safe and an unsafe nanoparticle. Or is there a difference at all?
Where does the cosmetic industry use nanoparticles?
Nanotechnology is used in three areas of the cosmetics production: formulation, packaging and manufacturing equipment. Well, it seems everything is alright with the packaging and equipment sections, while it is possible to develop antibacterial coatings or easy-to-clean surfaces. But when discussing nanoparticles in formulation everyone steps back a little.
Nanoparticles are used as the active ingredient, delivery vehicle or as a formulation aid. The particles can have very different morphologies and they can be organic, inorganic or both. As active ingredients nanoparticles can i.e. offer hair and dental care effects, as formulation aids they can function as thickening agents due to their unique rheological profile and as delivery vehicles they are employed to deliver fragile ingredients, such as vitamins, intact to the site of action.
Why they use nanoparticles?
Nanoparticles have different properties, like the high surface to volume ratio, from the same material in the bulk state. These changing properties can be for example solubility or optical properties. The best example is probably titania that is used in sunscreens because of it’s UVA/UVB reflective properties. Conventionally it is used as whitening agent but in the ‘nanoform’ it is transparent. This makes the sunscreen more pleasant to use while it won’t be like white paint on your skin. So, the goal of using nanoparticles is simply to improve the final product.
Why to worry?
The concerns are related to human and environmental safety. One of the most discussed issues for nanoparticles are their permeation through tissue barriers and whether the particles are degradable or not. Well, lots of good questions. Does the antimicrobial nano silver from my deodorant get into my systemic circulation? And is it for sure that the ceramides used in my shampoo degrade safely?
The most typical route of exposure considering cosmetic products is the dermal route. Our skin, however, serves a protective purpose and a healthy skin can prevent the nanoparticles entering viable tissues. Nevertheless it is also claimed that the smallest of the small (<30 nm particles) can be a potential health risk. There is just too much different combinations existing that it’s impossible to predict all of them.
The problem is the unawareness of the properties of these new materials, mostly due to lack of comparable methods that can be applied to the nanomaterials as well as to the bulks. The cosmetic industry among others is also lacking regulations and safety guidelines according to use of nanotechnology. That’s why I would recommend you to think: ‘Do I really need the properties in my cosmetics that are due to nanoparticles?’ So far, It’s up to you.
Wu, X. 2012. Nanotechnology in cosmetics: A Review. Cosmetics & Toiletries. Issue: April 2012.
Mihranyan, A.; Ferraz, N. & Strømme, M. 2012. Current status and future prospects of nanotechnology in cosmetics. Progress in Materials Science. Vol. 57, Issue 5, pages 875-910.