The influence of concentration, exposure duration, and patch occlusivity upon rabbit primary dermal irritation...

The Primary Rabbit Dermal Irritation Assay as described in the Federal Hazardous Substances Act (FHSA) is used by the Consumer Products Safety Commission (CPSC) to determine the labeling requirements of household products. One of the more obvious deficiencies of this assay is the descriptive imprecision for preparing the form in which solid materials are applied. Our experimental findings show that form and concentration of test material as well as the length of contact with the skin and the degree of patch occlusivity are prime factors influencing the degree of skin change. Four detergent granular products are evaluated. In the dry powder form with 4 hour exposure all the detergents were non-irritating. The paste at 24 hours under total occlusion was the most irritating.