"It seems that there is really very little publicly funded research looking into the effects of nanoparticles being taken into the body through the skin," said Sue Windebank, senior spokesperson for the Royal Society, the UK's leading scientific body. "The cosmetics companies may of course be doing their own research, but much of the information about what kind of safety assessments are being undertaken is not publicly listed."
A newspaper report in this week's Sunday Times focused on the use of nanoparticles in L'Oreal anti-wrinkle products, making specific reference to the brand Revitalift. L'Oreal claims that this product is absorbed quicker and deeper into the skin layers because of the microscopic particles which it refers to as nanosomes.
In July last year the Royal Society published a paper outlining the need for responsible development of nanotechnology. The report, which was commissioned by the UK government, stressed that the technology held the potential to be hugely beneficial, but that possible future uncertainties and risks must be fully explored.
In particular the report stressed that because nanoparticles often have their own chemical properties, they should be treated as new chemicals under both UK and European legislation, in an effort to initiate appropriate safety testing and labelling.
One year on and the Royal Society says it is still calling on cosmetic companies to make the results of their testing into nanoparticles public. That extensive research and development is going on in this field is not being disputed. L'Oreal in particular is said to be devoting a significant proportion of its €500 million budget into this area.
"Our concern is that manufacturers ensure that the toxicologal tests that they use recognize that nanoparticles of a given chemical will often have different properties to the same chemical in its larger form and may have greater toxicity," said Windebank. "It is certainly not a cloak and dagger situation with the cosmetics companies, but it would help if they were more transparent about the results of their safety tests."
At the time of publication L'Oreal had not yet responded to requests made by CosmeticsDesign.com, about the current status of its studies into the safety of nanoparticles in cosmetics formulations.
In the US, the FDA has taken a similar stand on the use of nanotechnology in cosmetics products. Citing the same concerns as the Royal Society, the FDA is currently considering whether a trialing and licensing system should be introduced in an effort to regulate the use of nanoparticles in cosmetics products.
For the time being the Royal Society recommends that ingredients taking the form of nanoparticles undergo a full safety assessment by the relevant advisory board before they are permitted for use in products. It also recommends that any products containing nanoparticles are labelled as such.
Estee Lauder is also incorporating nanotechnology into its anti-ageing formulations, but as well as this category, nanoparticles are also playing an important role in a number of advanced sunscreen formulations, proving particularly effective as ultra violet filters.
Nanotechnology involves the study and use of materials at an extremely small scale - at sizes of millionths of a millimetre - and exploits the fact that some materials have different properties at this ultra-small scale from those at a larger scale. One nanometer is the same as one millionth of a millimeter.
Industry experts see the use of nanotechnology and the incorporation of nanoparticles into skin care formulations as an area of immense potential for a category that continues to witness some of the largest annual sales growth.
In particular, sales in the global anti-aging category are growing at well into double figures. Retail sales of anti-aging skin care products are currently valued at nearly $2.5 billion (€1.9bn) in the US alone and the global market is estimated to be worth $6.9 billion in 2003, according to market research firm Kline & Company.