Cosmetic preservatives are vital to ensure a correct shelf life and safe consumer usage of the increasingly complex cosmetic formulations, combining the key features of efficacy, compatibility and regulatory acceptance together with good customer perception to make the preservative selection process increasingly difficult.
This process has become even more fraught due to the issue of parabens, a fungicide that has historically been one of the most popular preservative systems for cosmetics. Recent studies have shown that the preservative might have carcinongenic affects, which prompted the European Scientific Committee on Consumer Product to issue an opinion in January 2005 calling for more safety research and data on the issue.
The industry is also coming under further pressure on the issue of another fungicide, IBPC, which studies have shown could prove problematic to certain northern European populations with iodine deficiency. Both the issues relating to Parabens and IPBC are being investigated by the SCCP, which could in turn lead to the European Commission placing restrictions on the use of these substances as preservatives in cosmetics.
In answer to the growing pressure revolving around Parabens and IPBC, Lonza says it has devised the new Glydant XL Ultra formula in an effort to provide manufacturers with greater choice in preservatives.
Glydant XL Ultra is chemically described as a solid blend of Dimethylol Dimethyl (DMDM) Hydantoin, Sorbic Acid and Dehydroacetic acid. Lonza says that detailed development has produced a preservative that offers synergistical activity, enhanced stability, strong safety profile, formulation compatability, is solvent-free and complies with EU and US cosmetic regulations for leave-on and rinse-off.
Taking a closer look at the preservative's formulation, DMDM Hydantoin - a powerful bactericide and mild fungicide - has been used for over 20 years in Personal Care products and has a strong record of safety and efficacy. Likewise, Sorbic Acid and Dehydroacetic Acid - two organic acids - provide enhanced fungicidal action at low pH and are widely considered as some of the mildest and safest preservatives, being even allowed for food preservation in some parts of the world.
Lonza says that to comply with European regulations the ingredients in Glydant XL Ultra are listed on Annex VI to the Cosmetic Directive and the blend is allowed in all rinse-off and leave-on products up to a concentration of 1 per cent in the final product. The formula is also approved by the Cosmetic, Toiletry and Fragrance Association in the United States for both rinse-off and leave-on applications.
Lonza says that extensive testing of a 0.25 per cent Glydant XL Ultra formulas in cosmetic products achieves broad spectrum preservation of the formulation, leading to a 6 log decrease in microorganisms counts within 7 days after the initial inoculation, for both the bacterial and fungal groups of microorganisms.
According to the results, this means that the preservative should be used at typically 0.1 - 0.4 per cent of the final product in order to achieve broad spectrum preservation.
Lonza says that the ingredients for Glydant XL Ultra have been used for many years in cosmetic application and are proven to have excellent safety records. Given the proven efficacy of the formula, it prove to be a good alternative, particularly if regulations for other preservatives are tightened up in the future.