Abstract: Objective To determine the susceptibility to an itritant in the skin of different races.Methods A total of 32 subjects were included in the study and divided into three race groups: 8 Blacks, 16Caucasians and 8 Orientals.All volunteers were given patch test with sodium lauryl sulphate(SLS) (0.25%~2%) to the skin of upper back for 24 hours.The skin response was evaluated after removing test chambers.Results It was shown that minimal irritant dose(MID) levels were significantly higher in Blacks than those in Caucasions (P<0.05) but not in Orientals (P>0.05).It was observed that values of the transepidermal water loss (TEWL) and laser doppler velocimetry(LDV) increased significantly along with the increase of dosage of SLS in each of three race groups.There was no difference in values of TEWL and LDV among Caucasion,Black and Oriental groups.Furthermore, it was found that TEWL values significantly correlated with the visual scores in the three groups(Blacks r=0.83,P<0.01, Caucasions r=0.92, P<0.01, Orientals r=0.89,P<0.01).Conclusion The resuts indicate that dark skin has the same sensitive response to SLS itritation as light skin.

Key words: Dermatitis,irritant, Sodium lauryl sulphate, Skin