In a two-year project funded by Innovate UK, the new in vitromildness test was validated against human volunteer trials, with the in vitrodata accurately predicting the rank order of human in vivoclinical scores in all studies, finally allowing brands to determine “how gentle is gentle.” Producing results in as little as six – eight weeks, the XtraMild Test will enable companies to use credible scientific data to support their mildness claims.
The new test uses an adaptation of a regulatory skin irritation test, where subtle differences between mild and ultra-mild formulations can be measured by their ET50 score. This in turn allows a series of products to be placed into rank order of irritation potential (and therefore mildness). It provides a quick and cost-effective pre-screen, prior to human volunteer studies, driving key decisions in formulation development and providing valuable comparisons with industry benchmark products, said XCellR8.
Results acquired from the research project demonstrated how soaps performed against facial cleansers, and revealed how one brand’s soap was much milder that its equivalent facial wash and how some mass market soaps are in fact milder than more expensive equivalents.
The test is commonly used to assess new baby formulations such as shampoos, foam baths and body washes, providing critical insights into the mildness of the product and comparisons with leading brands. It is highly relevant for a wide variety of other formulation types including facial soaps, cleansers and other skincare items. The ET50 test can also be applied to cosmetic ingredients, such as assessment of the mildness of novel “mild” surfactants against classic surfactants, replacing the traditional tests which often lack relevance and the required level of sensitivity.
“Our company ethos to provide world-leading science with world-leading ethics really shone through with this project. Existing tests for mildness aren’t accurate as they were designed for irritant chemicals rather than today’s gentle cosmetic ingredients, and were benchmarked against unreliable animal data. In developing a new more sensitive test, we have been able to prove that in vitrotest results are as predictive as human volunteer trials as part of the project design. We no longer need to be dependent on out of date animal data as new in vitrotechniques provide such a good model of real-life exposure,” said Dr Carol Treasure, CEO and founder of XCellR8.
The research project also allowed us to look at the differences in facial cleansers and soaps in the current market place – and highlighted the mildness of many soaps, ultimately allowing the consumer to choose a product that is as mild to their skin as a facial wash whilst being more sustainably packaged.
The beauty of XtraMild is that it can bring together R&D and marketing, as formulators can now help marketing teams provide solid evidence for their mildness claims.”