This article is only available in the PDF format. Download the PDF to view the article, as well as its associated figures and tables. To the Editor.— The onychopathy described here, first noted by Samman and Johnston in 1969,1 is not common but very characteristic. On Feb 15, 1972, a 65-year-old white man used a phytosanitary product (Winter Volck Yellow, Sopra) for the treatment of fruit trees. He neglected the recommendation on the label and instead of mixing 1 liter of the product with 50 liters of water, he handled the chemical in a pure state for three hours. After 15 days, he noticed some change in the color of his nails. Two months later, the nails appeared to be made up of two portions: the proximal third of the nail plate was yellow and the distal two thirds was pink. The cuticle was absent and there was a slight painless paronychia (Figure). Seven months later, edema of the proximal nail fold had not completely Appearance of nails after two months. disappeared. A