258 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Although I have never observed other untoward cutaneous reactions, their occurrence is to be expected if inherent to the tested substance. Reference is made to the effect of monobenzyl ether of hydroquinone that causes loss of pigment, to lichen planus-like eruption caused, according to Buckley (5), by a hydrochloride salt of the substituted p-phenylenedi- amines. This eruption is an occupational dermatosis occurring in workers exposed to developing solutions of color films. Buckley has reproduced this reaction by patch test with the aforementioned chemicals. Photosensi- tizing action of the tested substance would doubtless be elicited if the study was conducted in summer and the subjects exposed to the sun. Figure 3.--Snowing grac•auons ot posture reacuons. Site • was I plus, B was 2 plus and C was 3 plus. The sites of other patches shown in the pho- tograph showed no reaction. The role of perspiration in facilitating untoward cutaneous reaction of thq tested substance is more likely to be operative in the repetitive method, especially if the study is conducted in warm weather. DISCUSSION OF RESULTS Results of study of different substances by the repetitive method are shown in Tables 1 to 6. The number of applications varied from 10 to 15 the subjects used were 50 to 100. The application of the tested sub- stance was applied to the same site. I favor this procedure since it is more likely to elicit the aforegoing untoward reactions than does applications at random sites.

INSULT PATCH TESTS IN STUDY OI CUTANEOUS REACTION 259 Figure 4.--A subject in Tabl 4. Area marked A shows solitary and con- fluent punctate redness that centered around a follicle--folliculitis. It evi- denced irritant action of the tested substance on the follicles. Area marked B shows confluent lesions of fo!liculitis in addition, dry wrinkled skin. These reactions are distinctive, not typical, of primary cutaneous irritant reaction, but such reaction later appeared and was expressed as diffuse redness (comparable to Figure 3). Table I: The topical hand cream was applied as is, the results were ideal there was no evidence of primary initant, fatiguing or allergenic action. Table 2: To avoid primary irritant action on initial application of the waterless hand cleanser, a pilot study suggested using a 25 per cent dilu- tion in water. As seen in the table, five subjects reacted to this dilution on second application for these subjects 15 per cent dilution was subsequently used. Nineteen of the 52 subjects showed mild fatiguing reactions appearing predominantly late in the course of 15 consecutive applications. The one