SUMMARY.— Manganese levels in normal epidermis and dermis from 34 cadavers were estimated by neutron activation analysis. The mean concentration of manganese in the epidermis was 4 times higher than that in the dermis. An important biological role of manganese in skin is suggested by the remarkably narrow range of concentration of that trace metal in the analysed samples.

Copper and zinc levels were estimated in serum and skin of nineteen vitiligo patients as well as in pigmented moles, seborrhoeic warts and normal skin. In seborrhoeic warts, high zinc levels were associated with excessive melanization and an abundance of ATPase-t-ve dendritic cells. Zinc levels were also significantly increased in pigmented moles compared with those in normal surrounding skin.In vitiligo, there was a significant reduction in serum zinc while copper levels were increased in the hyperpigmented zone surrounding the lesion. The results of copper analysis in vitiligo neither support a deficiency role for copper nor justify its use in the treatment of that disease.