Factors predisposing to cutaneous irritation.

In experimental skin toxicology, as well as in clinical practice, considerable interindividual variation in the susceptibility to irritant dermatitis is noted when irritant doses are low. Cutaneous sensitivity and hypersensitivity are not determined by a single known feature but are multifactorial. Previous atopic dermatitis may predispose to irritant dermatitis. Susceptibility to irritation seems to be influenced by age, race, and genetic background, whereas sex-related differences do not seem to exist. Of biophysical skin baseline features, skin-surface pH was correlated with the severity of experimentally induced irritant dermatitis, but baseline transepidermal water loss, water-holding capacity, stratum corneum turnover time, and sebum content were not.