Changes of a Chemical Component of Human Fingernails with Age: Correlation between the Amount of Red Chromogen and Age

Abstract

Fingernail specimens were taken from 339 Japanese subjects assigned to one of six age groups. Red chromogen was obtained by the reaction of nail samples with a 66% aqueous solution of sulfuric acid in a boiling water bath. Although the structure of the red chromogen was unidentified, the content of chromogen was found to be correlated with the age of the subject. The values for the concentration were remarkably high in newborns, infants and children (group I), but decreased gradually by the age of 10(group II). There was no appreciable difference between values in adults.