ABSTRACT
Animal tests mandated by regulatory agencies are routinely used to screen materials for their capability to produce acute irritation and corrosion. Many consumer product companies and others interested in predictive testing have developed animal assays for ranking materials within selected product classes. Cumulative irritation is most often evaluated in humans. This chapter deals with factors affecting skin irritation potential that may be manipulated to develop more sensitive in vivo and in vitro skin irritation assays. Primary irritation and corrosion are usually evaluated by modifications of the method described by John Draize and his colleagues. Assays evaluating the capacity of chemicals to produce acute irritation and corrosion differ extensively from those used to predict cumulative irritation. The guinea pig immersion assay was developed to evaluate the irritancy of aqueous detergent solutions and other surfactant-based products. An open application procedure in guinea pigs uses microscopic examination of skin biopsies of sites treated with weak irritants to rank materials.
