M. Leschke, W. Siegert | Personal Care Europe | 9-2008
ABSTRACT: The topic of preservation is always of importance to formulators and finished goods marketers. Formulators are aware of the necessity to adequately preserve their products in order to ensure product safety and be in compliance with legislation. This task is made much more difficult when marketing requirements are added to the factors influencing the preservative choice. Demands such as global approval, soft preservation, “free of…”, etc have limited the number of acceptable actives. Increasing marketing pressure has resulted in an interest in reducing the amount of traditional preservatives in cosmetic formulations or in finding novel ways to keep cosmetic products microbiologically stable. It is now more important than ever that preservation or microbiological stability is an integral part of new formulation concepts. At an early stage of product development, formulators must consider all possible methods of enhancing the efficacy of traditional reservative actives, e.g. using chelating agents or multifunctional materials. There are some ingredients known in the market which can boost the efficacy of preservative actives without having their own antimicrobial effect. Chelating agents are able to enhance the efficacy of most preservatives. This occurs as the chelator removes metal ions from cell walls of the microbes. The weakened walls then allow the biocide to penetrate and destroy the microorganisms. Although the boosting effect of chelating agents on preservatives is well known, the environmental fate of these materials has been debated. To avoid the environmental discussion about chelating agents, readily biodegradable alternatives have been introduced to the market.