Non-invasive diffuse reflectance measurements of cutaneous melanin content can predict human sensitivity to ultraviolet radiation.

The diversity of human skin phenotypes and the ubiquitous exposure to ultraviolet radiation (UVR) underscore the need for a non-invasive tool to predict an individual's UVR sensitivity. We analysed correlations between UVR sensitivity, melanin content, diffuse reflectance spectroscopy (DR) and UVR-induced DNA damage in the skin of subjects from three racial/ethnic groups: Asian, black or African American and White. UVR sensitivity was determined by evaluating each subject's response to one minimal erythemal dose (MED) of UVR one day after the exposure.

Short- and long-term effects of UV radiation on the pigmentation of human skin.

The incidence of skin cancer, including cutaneous melanoma, has risen substantially in recent years, and epidemiological and laboratory studies show that UV radiation is a major causative factor of this increase. UV damage also underlies photoaging of the skin, and these deleterious effects of UV can be, in part, prevented in skin with higher levels of constitutive pigmentation. We review the clinical studies we have made in recent years regarding the rapid and the long-term responses of the pigmentary system in human skin to UV exposure.

Dynamics of pigmentation induction by repeated ultraviolet exposures: dose, dose interval and ultraviolet spectrum dependence.

Background: The dynamics of ultraviolet (UV)-induced melanogenesis have been well characterized for single UV exposures. However, our knowledge of the effects of repeated UV exposures on the development of new pigmentation is limited.

Objectives: To characterize the dynamics and dose dependence of pigmentation induction by repeated UV exposures using two different UV sources.

In vivo measurement of skin erythema and pigmentation: new means of implementation of diffuse reflectance spectroscopy with a commercial instrument.

Background: Various physical, chemical and biological insults, including exposure to ultraviolet (UV) radiation, cause erythema and change in pigmentation in human skin. These reactions provide an important measure of the cutaneous response to the insult.

Objectives: To present a new implementation of a method for objective in vivo measurement of erythema and pigmentation.