Isobornyl acrylate: an impurity in alkyl glucosides

Abstract Context: Alkyl glucosides and alkyl poly-glucosides are widely used as wetting agents, surfactants and emulsifiers in several industrial and cosmetic products. They are known as well-tolerated and are usually added to the primary surfactants in order to reduce the irritating potential of the main foaming agents. Objective: Recently, some authors suggested that allergic contact dermatitis to alkyl glucosides might be more frequent than suspected. On the other hand, the chemical structures of glucosides do not show potentially allergenic chemical groups or strongly polarized structures. The aim of our study is to investigate alkyl glucosides carrying out a detailed chemical analysis on samples of raw materials to identify potentially allergenic impurities or by-products contained in commercial samples of alkyl glucosides. Materials and methods: We chemically analyzed samples of cocoyl glucoside, decyl glucoside and lauryl glucoside by three different analytical methods, in order to identify any undesired or polluting substances. Result: In each of the three samples, we detected the presence of isobornyl acrylate. Its approximate content in the tested samples is 500 ng/g of the product. Discussion: Isobornyl acrylate is not used in the synthesis of alkyl glucosides, but as a plasticizer in many plastic materials. It can be easily released to materials flowing over these surfaces when they have high extraction power, as glucosides. Conclusion: Isobornyl acrylate may play a role as hidden allergen, in the form of an impurity collected during the industrial process, explaining some cases of allergic reaction to alkyl glucosides.