Nanotechnology in Cosmetics
The applications of nanotechnology and nanomaterials can be found in many cosmetic products including moisturisers, hair care products, make up and sunscreen. In cosmetics, nanoparticles are used for various purposes, including to enhance the delivery of active ingredients, improve the appearance and feel of products, and provide sun protection.
For example, nanoparticles can be used to create more effective sunscreens by allowing for higher levels of active ingredients to be delivered to the skin while still remaining transparent. They can also be used to improve the texture and appearance of cosmetics, such as makeup and skin care products, by providing a smoother, more even application.
However, there are also concerns about the safety and potential health risks of using nanoparticles in cosmetics, as they are so small that they can easily penetrate the skin and potentially cause harm. As a result, the use of nanotechnology in cosmetics is a topic of ongoing research and debate, and regulations regarding its use may vary from country to country.
Nanoparticles in cosmetics as UV filters
Nanoparticles are often used as ultraviolet (UV) filters in cosmetics because of their unique properties. When incorporated into cosmetic products, nanoparticles can provide an effective barrier to protect the skin from harmful UV rays.
One of the main advantages of using nanoparticles as UV filters is that they can provide high levels of protection while still remaining transparent. Traditional UV filters can sometimes leave a visible residue on the skin, but nanoparticles are so small that they can be incorporated into cosmetic products without affecting the appearance of the product.
Additionally, nanoparticles can provide a more even distribution of UV filters on the skin, helping to ensure that the skin is protected from UV exposure. By providing a consistent level of protection, nanoparticles can help to reduce the risk of skin damage and reduce the risk of skin cancer.
The main compounds used as UV filters in cosmetics that utilize nanotechnology are zinc oxide (ZnO) and titanium dioxide (TiO2). These materials are commonly used because they are highly effective at blocking UV rays, non-toxic, and safe for use on the skin.
Zinc oxide is a white powder that is often used in cosmetics as a physical UV filter. It works by scattering and reflecting UV rays, thereby preventing them from penetrating the skin. Zinc oxide is a very effective UV filter, providing protection against both UVA and UVB rays.
Titanium dioxide is another white powder that is commonly used as a UV filter in cosmetics. Like zinc oxide, titanium dioxide works by reflecting and scattering UV rays, providing protection against both UVA and UVB rays. It is also a safe and non-toxic material that is well-tolerated by the skin.
Nanoparticles in cosmetics drug delivery agents
The second use is nanotechnology for delivery. Liposomes and niosomes are used in the cosmetic industry as delivery vehicles. Newer structures such as solid lipid nanoparticles and nanostructured lipid carriers have been found to be better performers than liposomes.
In particular, nanostructured lipid carriers have been identified as a potential next generation cosmetic delivery agent that can provide enhanced skin hydration, bioavailability, stability of the agent and controlled occlusion. Encapsulation techniques have been proposed for carrying cosmetic actives. Nanocrystals and nanoemulsions are also being investigated for cosmetic applications. Patents have been filed for the application of dendrimers in the cosmetics industry.
A draft guidance documents from the FDA "Guidance for Industry: Safety of Nanomaterials in Cosmetic Products" discusses the FDA's current thinking on the safety assessment of nanomaterials when used in cosmetic products. Key points include:
The legal requirements for cosmetics manufactured using nanomaterials are the same as those for any other cosmetics. While cosmetics are not subject to premarket approval, companies and individuals who market cosmetics are legally responsible for the safety of their products and they must be properly labeled.
To conduct safety assessments for cosmetic products containing nanomaterials, standard safety tests may need to be modified or new methods developed.
Examples of new nanotechnology applications in personal care products include (from the IEHN report "Beneath the Skin: Hidden Liabilities, Market Risk and Drivers of Change in the Cosmetics and Personal Care Products Industry" (pdf):
Penetration enhancer - Encapsulating or suspending key ingredients in so-called nanospheres or nanoemulsions, increases their penetration into the skin:
L'Oreal (which ranks No. 6 in nanotechnology patent holders in the U.S.) has used polymer nanocapsules to deliver active ingredients, e.g. retinol or Vitamin A, into the deeper layers of skin. In 1998 the company unveiled Plentitude Revitalift, an anti-wrinkle cream using nanoparticles.
Freeze 24/7, a new anti-wrinkle skincare line is planning to incorporate nanotechnology in future products.
La Prairie??s product, the Dollars 500 Skin Caviar Intensive Ampoule Treatment, claims to minimize the look of uneven skin pigmentation, lines and wrinkles in six weeks using nanotechnology.
La Prairie's vice president of retail marketing and training, Holly Genovese, says the nanoemulsions in the product 'optimize the delivery of functional ingredients into the skin and allow these materials to get to the site of action quicker'.
Procter & Gamble's Olay brand was designed with nanoemulsion technology in 2005.
Other companies using nanotech in their skin products as of 2005 include: Mary Kay and Clinique from Lauder; Neutrogena, from Johnson & Johnson; Avon; and the Estee Lauder brand.
Hair products – using nanoemulsions to encapsulate active ingredients and carry them deeper into hair shafts.
PureOlogy began experimenting with nanoemulsions in 2000 when the company's founder set out to create a product line especially developed for color treated hair.
Sunscreens – the zinc and titanium in sunscreens are 'micronized', making them transparent, less greasy, less smelly and more absorbable into the skin.
DDF planned more nanotechnology-enhanced anti-aging products as of 2004.
Colorescience markets a product named Sunforgettable, a powder which contains titanium dioxide nanoparticles.
Paris-based Caudalie launched its Vinosun Anti-Aging Suncare, a sunscreen and anti-aging treatment that relies on 'nanomized' UV filters and antioxidants, in the US in 2003.
Safety issues
The use of nanomaterials in cosmetics is a topic of ongoing research and debate, and there are concerns about their potential impact on human health and the environment. Some of the key safety issues and concerns regarding the use of nanomaterials in cosmetics include:
Toxicity: There is concern that nanoparticles may be toxic when they come into contact with the skin, or when they are ingested or inhaled.
Penetration: Nanoparticles are so small that they can easily penetrate the skin, which raises concerns about their potential to cause harm to internal organs.
Environmental impact: There is also concern about the potential environmental impact of nanoparticles, as they can persist in the environment for a long time and may have harmful effects on wildlife and ecosystems.