Development of in-vivo test models for skin protective products as a tool to determine and rate their efficacy

Status:

completed 07/2012

Aims:

Topical skin protection products are used at workplaces with exposure to wet work and mild irritants to prevent cumulative irritant dermatitis. Different irritants relevant in the occupational setting had to be considered and categorized and protective reference standards had to be implemented in order to relate the protection potential of marked products to the reference standards.

Activities/Methods:

In the context of this research project, a cooperation between the Universities of Erlangen, Heidelberg, Jena and Osnabrück, a 5-day human in-vivo evaluation model for the efficacy assessment of skin protection products for several representative exposure situations was developed.

Results:

Defined model irritants and two defined generic reference standards (formulations) for protective products were implemented, and an efficacy index was generated. Within the project, three relevant categories of hydrophilic irritants were identified that are especially important as risk factors for the irritant contact dermatitis. These included irritants with alkaline and acid pH and detergents. As representatives for these categories, partly previously reported, partly new substances were evaluated in human test model experiments, and the most suitable substances were selected. The concentrations and exposure times were selected that lead to a sufficient and reproducible degree of irritation after repetitive exposure within four days. The thus developed evaluation model for the efficacy assessment of skin protection product was finally validated in a multicenter study thus showing the transferability of the model and the reproducibility of the results. The developed evaluation model may be used for future efficacy tests of occupational skin protections products in comparison to the developed generic reference standards. It allows for the simultaneous assessment of several skin protection products on the basis of an efficacy index. These results can be used by industry in product development and may lead to a better transparency of products on the market for users and preventive services. Thus the results of this research project are of relevance for the German Statutory Accidents Insurance in charge of the prevention of occupational skin diseases in Germany.

Last Update: