DAMAGE TO THE SKIN BY REPETITIVE WASHING

Damage to the skin following the repeated use of 2 different wash solu tions was investigated. Stratum corneum capacitative resistance, strat um corneum lipids, transepidermal water loss, skin surface pH, laser D oppler flow and skin reddening were determined. All skin function para meters already showed a marked change after a single wash (e.g., the m edian of TEWL values increased by more than 0.5 g/m(2) h). Repetitive washing for 1 week led to a further deterioration of TEWL and corneome try values (e.g., TEWL increased for about 2.9 g/m(2) h after repetiti ve washing with sodium lauryl sulfate). The rate of skin function rege neration after repetitive washing was unaltered compared to regenerati on after a single wash. The surfactants used showed quantitatively dif fering effects on corneometry, TEWL and laser Doppler flow (e.g., afte r repetitive washing with Geliderm, the median of TEWL values increase d only up to 1.55 g/m(2) h). However, damage arising from repetitive w ashing could not be completely prevented by the selection of a mild su rfactant. Skin function regeneration showed no difference with the 2 s urfactants used.