48 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS site where the cosmetic was applied. 5. The morphe of the dermatitis is that of a dermatitis vene- nata namely, erythema, ß edema and sometimes papules and vesicles. 6. Patch tests with the cosmetic on normal parts of the skin should be positive. It must be remembered that patch tests are only performed with cosmetics which are not in- tended to have a primary irri- tant action on the skin. In cases where patch tests may not simulate the manner in which the cosmetic when used remains on the skin, actual usage tests should be per- formed. In case photosensi- tivity is suspected as playing a role in the dermatitis, the site on which the cosmetic was tested should be exposed to the sun for an hour or longer. 7. When the use of the suspected cosmetic is discontinued, the dermatitis should show marked and rapid improve- ment and re-use of the cos• metic after the eruption dis- appears should result in a re- currence of the eruption. DERMATITIS FROM CREAMS Dermatitis from face creams is of rare occurrence. In the last 12 years there are only 5 reported cases in the American medical literature and 1 of these was lead poisoning in an actress from grease paint con- taining 40 per cent white lead. The other 4 cases were due to hyper- sensitivity to petrolatum, trietha- nolamine, methyl heptin carbonate and a case of slate gray pigmenta- tion of the face from the ammoni- ated mercury in a freckle cream. Dermatitis is more likely to occur from freckle creams, bleaching creams, vanishing creams, and cleansing creams than from the so- called nourishing creams. No cases of dermatitis have' been reported from hormone creams. In order to diagnose dermatitis from creams, the suspected cream should be used as a covered patch test on the patient and on a control. The patch can remain on for 24 hours and if no reaction occurs, the site of the patch should be inspected each day for 3 days to observe the appearance of late reactions. If none occur, then the patient should use the cream under supervision on the forearms for 3 or 4 days to ob- serve the effect on the skin. If there still is no effect, then the cream may be dismissed as a cause of dermatitis. If there is a positive patch test on the pati'ent and a nega- tive one on the control, or if the application on the arm causes a dermatitis, then the ingredients o! the cream should be ascertained and similar tests should be performed with each in order to find the actual irritant. Cosmetics other than the cream should be' suspected if no positive results occur from tests with the cream. If tests with the other cosmetics are also negative, then another source for the derma- titis should be sought.

DIAGNOSIS OF COSMETIC DERMATITIS 49 ANTI-PE RS PIRANTS AND DEODORANTS Dermatitis in the axilla is not un- common from the use of anti- perspirants. Solutions containing high concentrations of aluminum chloride have been more at fault than those containing aluminum sulfate. The anti-perspirants swell the epithelium at the mouth of the sweat ducts and thus tend to close the openings and dam back the per- spiration. This may result in cyst formation, and sometimes in secon- dary infection forming pustules. The diagnosis is made from the appearance, site of the lesions, and the history of using an anti-perspir- ant. Patch tests are unnecessary. 'Dermatitis has not been reported from deodorants powders. The dis- eases to be considered in differential diaghosis, are furunculosis, hydra- denitis suppuritiva Fox-Fordyce dis- ease and Acanthosis Nigricans. HAIR PREPARATIONS These have caused the majority of cases of dermatitis from cos- metics. The synthetic hair dyes, the chemical hair wavers, straighten- ers, depilatories, hair lacquers, and hair tonics, have been the worst offenders. HAIR DYES The vegetable hair dyes, henna, sage tea, walnut hull juice, indigo (used with henna to produce brown shades) have caused no trouble. The metallic salt of lead, silver, copper, cadmium, and tin have not caused dermatitis, but argyria has been reported from hair dyes con- taining silver. Lead poisoning has not been reported from salts of lead used for hair dyes. Since the parenting of para- phenylenediamine in 188a by Erd- man for dyeing hair and feathers, there have been thousands of cases of dermatitis from hair dyes con- taining it. Conjunctivitis and keratitis re- suiting in blindness in a few cases occurred from the use of para- phenylenediamine as an eye lash and eyebrow dye. So many cases of dermatitis re- sulted from the use of para- phenylenediamine that in some countries its use on humans is pro- hibited and in others tests are re- quired to be performed on the sub- ject before it can be applied as a hair dye. Paraphenylenediamine, para- to]uylenediamine, paramidophenol, and aniline black, and other re- lated oxidation dyes are the chief causes of dermatitis and asthma among furriers using them as fur dyes. The predyeing patch test with paraphenylenediamine is useless because sensitization is established at least 5 days after the hair is dyed, therefore unless the pa- tient was sensitized by the hair being dyed with it previously, or the pa- tient was sensitized by wearing fur, dyed with paraphenylenediamine, the patch test will be negative and still the dermatitis may occur 5 days after the hair is dyed. The actual irritant in dermatitis from paraphenylenediamine is one of the