TNO ups sunscreen testing

TNO​ focuses on skin metabolism, testing for products from the cosmetics, pharmaceutical as well as food and beverage industries. But in recent years one of the company's key specialist areas has become the testing of sunscreen products. The evolution of its UV testing capabilities follows the growth of a category that is now one of the fastest growing in the cosmetics and personal care industry.

"Our testing focuses on skin metabolism, absorption and its effects on individuals,"​ said Wim Meuling, director of Human Volunteer Studies at TNO in a presentation given at In-Cosmetics in Berlin, this week.

"The procedure for all our testing is very strict. Firstly good clinical process and practice has to be agreed and then approved by the Medical Ethics Committee. Once permission has been granted we can then start the research, which is conducted under 24 hours surveillance."​

The TNO database contains over 6,000 volunteers, who are individually screened according to the requirements of the particular study. The company's facilities allow that, at anyone time, up to 12 volunteers can be simultaneously studied at any one time.

The company's activities have evolved into a variety of dermatology applications for cosmetic products, including creams, patches and ointments as well as pharmaceutical and cosmeceutical products. Testing itself is conducted in a number of ways, including strips or direct application to the skin.

The reaction can then be tested in samples of bodily waste and exhaled air. Studies assess the level of irritation to the skin as well as looking at the efficacy of the product. In the case of sunscreen products the test will estimate just how effective the product is in combating the affects of UV radiation.

"In line with the growing demand for increasingly comprehensive sun protection for both UVA and UVB rays, the company tests the efficacy of UV absorbers on the skin, assessing it in contrast with untreated areas,"​ Meuling said.

Typically testing of UV rays takes a tiered approach that uses mass balanced technique with a radio labelled compound. Taking a large skin area, usually on the back, the testing involves two applications of the absorber over a determined period of exposure to artificially created radiation levels.

After each application the area of treated and untreated skin is assessed taking in the exact impact of the UV absorber after exposure. On top of that the test also estimate the amount of the UV filter that has been absorbed by the body as well as the amount excreted. Meuling says that the results often determine whether or not a company needs to make adjustments to its formula.