EFFECTS OF WATER TEMPERATURE ON SURFACTANT-INDUCED SKIN IRRITATION

Surfactant-induced irritant reactions may be elicited by several endog enous and exogenous factors. Among these, surfactant concentration, an d duration and frequency of exposure play important roles. The study f ocuses on the influence of water temperature in determining damage of the skin barrier. 10 subjects of both sexes entered the study. 4 areas (4 x 4 cm(2)) were randomly selected on the volar forearm and were tr eated with a daily open application of 5% sodium lauryl sulphate for 4 days. The solutions were at 3 temperatures: 4 degrees, 20 degrees and 40 degrees C. One site served as untreated control. On the 5th day, s kin irritation was evaluated using transepidermal water loss (TEWL) me asurements, erythema (a value), skin reflectance (L* value), hydratio n (capacitance) and desquamation (stripping). The results show a signi ficant effect of the solution's temperature in determining skin irrita tion (P < 0.001). Skin damage was higher in sites treated with warmer temperatures and a highly significant correlation (P < 0.001) between irritation and temperature was found. In conclusion, the study shows t hat water temperature during washing has an important effect on the on set of irritant contact dermatitis.