192 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Role of Sweat and Lipids as 13•ell as the Subsurface Receptacle in Skin Conditions ]3resenting Excessive Greasiness or Oiliness That genius among dermatologists, Unna (P. G.), was to my knowledge the first to interpret seborrhea not merely as a flow of sebum but actually as "steathidrosis," i.e., "fatty sweat" (52). The basic importance of this interpretation regarding disturbed sweat/lipid ratios need scarcely be emphasized. It is fundamental to the understanding of the pathogenesis of that vast and important--even though somewhat ill-defined--category of skin diseases known as the "seborrheic dermatoses." And if I add that, in this category are included such apparently minor variants as "shiny noses," "large pores" (patulous follicular orifices), "greasy" and "thick" skin, "oily hair" and even the common forms of greasy and tallowy "dan- druff," as well as seborrheic loss of hair, this will surely suffice to demonstrate to this particular audience the necessity for taking cosmetologic•l notice of this kind of sweat disturbance. Regardless of whether their basis is primarily an excessive or otherwise faulty sebum formation, or an exces- sive sebum delivery secondary to and a consequence of excessive amounts and/or excessive emulsifying capacities of sweat, the fact is that seborrhea and seborrheic states are associated with abnormalities of sweat as well as those of sebum and both are often found together with abnormalities of the closely related process of horn production. The parallelism .of these three forms of aberrations is well illustrated in the common cosmetic prob- lems of ache vulgaris with its pimples, blackheads, "greasy" and "oily" skin, hair and scalp, etc. Some recent clinical investigations throw con- siderable new light upon the local pathologic processes involved in acne vulgaris and seborrheic states. For not only can one demonstrate an increase of keratinous material--as in the blackhead and whitehead and generally "thickened" skin surface, but also a disturbance in the surface lipid/sweat ratios. Both our own quantitative studies and those of others have demonstrated significantly augmented lipid values on the face and trunk (preferred ache and seborrheic areas) of patients with ache vulgaris (53, 54, 22). Moreover, in precisely the same regions, the delivery of thermal sweat was also increased (22). But perhaps more impressive still was the finding of an abnormally high ratio of the lipid to the aqueous components, i.e., there was also a relative excess in the quantity of lipids (22).* In "oily seborrhea," such as found not only in ache patients but also in * I have found it most interesting to speculate on the aptness of the term "kerose" coined by the French master-dermatologist Darier to describe a thickened skin surface with abnor- mally oily and fatty surface film. To me the word itself connotes the tri-fold nature of the disturbance--"KE" for "KEratin" "OS" for "hidrosis" and "SE" for "SEborrhea." Of course this is not a correct etymological, but simply a mnemotechnical interpretation of the syllables. Nevertheless "KEROSE" brings to light very clearly Darier's recognition of the role of keratin as an essential component of a seborrheic process.

CLINICAL DISTURBANCES IN SWEATING 193 persons without acne, the analytic data of different investigators strongly suggest that in this condition it is the "horn-wax" (epidermis-derived lipids) which is excessively emulsified in the surface film [Marchionini, Mant and Huss (55), Hodgson-Jones, MacKenna and Wheatley (56) and our own findings]. An extreme degree of oily seborrhea exists in so called hyperhidrosis oleosa which Darier includes among the "keroses" (57). This condition causes pillows, laundry, hats, etc., to be constantly soiled by the oily liquid coming from the skin and in this condition it has been demonstrated that control of hyperhidrosis constitutes the pri- mary objective of any helpful treatment. It must be stated here that in general the external treatment of exces- sively oily-greasy skin and hair leaves much to be desired. As already remarked in my previous comments, repeated application of the stronger grease solvents all too often leads only to a compensatory increase in the rate of formation and delivery of oil and grease. Noteworthy for our thesis that delivery of sweat and emulsification by sweat are important components of the process by which surface lipids are supplied and distributed is the fact that oily and other seborrheas are generally at their worst when the weather is such as to favor relatively large amounts of sweat remaining for relatively long times on the skin surface, i.e. in humid hot weather and at their best when the environ- ment does not favor the accumulation of surface sweat, i.e., in relatively dry weather. One of the few really effective ways of reducing oiliness and excess grease of the skin is by radiation therapy. As demonstrated independently by practically simultaneous studies of my own co-workers and of Jadas- sohn's school, x-rays administered to the skin produce a sharp reduction in the amount of surface grease (22, 41). In our studies we were able to demonstrate not only this fact, but also the regular parallelism between the x-ray induced reduction of surface lipids and the improvement of ache (22). In how far this reduction of greasiness may be associated with or dependent upon a reduction of sweating produced by the rays is still a matter for conjecture. However, this appealing hypothesis is somewhat weakened by our own findings that after the x-radiation of a skin area the local reduction in amounts of sweat delivered was not so great as the local reduction in amounts of lipids. Role of Sweat and Lipids as l/Fell as of Subsurface Receptacle in Skin Condi- tions Presenting Excessive "Dryness" or "Scaliness" Just as is the case in excessive oiliness, it is quite apparent that excessive dryness and scaliness of the skin surface and skin appendages is locally and mainly dependent upon the three interlocking factors--surface lipids, surface sweat and surface horny material.