Alternative Testing Methods For Estimating The Skin Sensitization Potential Of Natural Products

Determination of skin sensitization is a critical toxicological endpoint in the safety evaluation of chemicals including natural products in cosmetics and personal care products. With the regulatory agencies' push to ban animal testing for cosmetic ingredients, and many organizations proactively choosing to eliminate animal testing due to ethical considerations, non-animal alternative methods are increasingly being used for safety assessment. Skin sensitizers are usually small molecules containing reactive functional groups, called mechanistic domains, which can covalently bind to biological nucleophiles at a cellular level. Such reactivity features have been exploited to develop numerous in chemico, in vitro and in silico methods as non-animal alternatives to identify potential skin sensitizers.

A brief overview of the state-of-the-art methods for detecting the potential sensitizers; progress in alternative methods; the pro's and con's of regulatory agencies recommended methods; development of fluorescence based in chemico methods as well as application of fluorescence methods for analysis of natural products and mixtures with examples will be discussed.