Skin reactions to irritants assessed by polysulfide rubber replica.

Skin damage after application of experimental irritants was evaluated under blind conditions and by the use of polysulfide rubber replica. Closed patch tests with 7 different irritants, solvents and empty chambers were applied to 16 volunteers, and the skin damage was evaluated visually and by a replica technique after 24, 48 and 96 h. We found that 3 of the irritants (sodium lauryl sulphate, hydrochloric acid and croton oil) were capable of causing specific and significantly different patterns of skin damage. The patterns could be divided into papular (hydrochloric acid, croton oil) and non-papular (sodium lauryl sulphate, sapo kalinus, sodium hydroxide) types. Nonanoic acid caused a non-paular pattern, but propanol, used as a solvent, by itself also produced a non-papular pattern. The time between application of the irritant and appearance of the characteristic alteration in the skin surface differed, depending on the irritant applied.