The dissolved constituents of human sweat

Abstract

The paper contains analyses of the total dissolved constituents of human sweat, including variations in their proportions in different individuals and under different physiological conditions. In different individuals the proportions of Cl, Na, and K varied considerably. Lactic acid was present in pure sweat in much higher proportion than in the blood, but no evidence could be obtained that the sweat-glands take any active part in regulating the proportion of lactic acid or any other substance in the blood. The composition of sweat as actually obtained from the skin without very special precautions was found to be much influenced by substances given off from the general surface of the epidermis; and the ordinary acid reaction of such sweat, which may be as great as pH 4.4, was found to be due entirely to these substances, the reaction of sweat itself being slightly alkaline, like the reaction of blood.