334 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS Allantoin Several dermatologists have been reported by Mecca (14) to have shown that aluminum allantoinates enhance antiperspirant action of other aluminum salts while reducing their irritation potential consider- ably. Kahan and others (15, 16) have reported that 0.2% allantoin in creams or talcums help prevent diaper dermatitis (generally considered to be caused by ammonia liberated from the urine). The author observed (of. preceding pages) that addition of all antoin to lipsticks containing bromo acids made them tolerable to women who could not otherwise use them. In contrast, it was shown in the pre- ceding pages that addition of 0.25% aluminum chlorhydroxy allantoinate to an antiperspirant containing both aluminum chlorhydroxide and a quaternary antiseptic increased eye irritation, perhaps due to activation of the cationic agent. A nion- Cation Complexes Use of equimolar mixtures of anionic and cationic surfactants in certain shampoo compositions (which contain substantial amounts of amphoteric surfactant) is claimed by Goff (20) to result in preparations which foam well and leave the hair in good condition. The amounts of eationic recommended (up to 4.9%) would normally be extremely irritating to the eye. Eye irritation is not discussed in the patent, but it must be presumed that the anti-irritant activity of the amphoteric is greatly helped by neutralizing the cationic via "complexation" with the anionic surfactant. A ryloxypropionates A rather well documented paper by Northover and Subramanian (21) shows that formaldehyde-induced inflammation can be inhibited by a number of these substances, some of which will also inhibit reaction to intradermal injection of histamine. Cortisone acetate was inactive. This study did not involve cosmetic ingredients and was performed via intradermal techniques rather than topical application. Neverthe- less, it may have considerable application to cosmetics. Azulene Ruemele (22) used a large quantity (0.25%) of 1,4 dimethyl-7 isopropyl azulene in an unspecified alkaline depilatory formula which was routinely applied to the face as well as arms and legs. He claims distinct anti irritant action but offers no data to prove it. It was shown

USE OF ANTI-IRRITANTS IN COSMETIC FORMULATING 333 above (cf. preceding pages) that inclusion of 0.1% of the same ("guaia") azulene in an aerosol cologne greatly reduced eye irritation. Hertz (23) showed the value of 0.02-0.50% azulene in reducing eye irritation caused by deliberate instillation of mustard oil. Hertz also points out that its activity is lost if the azulene is solubilized with Tween 60. Carboxymethyl Cellulose Kuchinka (24) discusses the skin protective effect of CMC when used in combination with various surfactants. Cetyl Alcohol A number of cosmetic chemists feel that cetyl alcohol reduces eye irritation of shampoos, and eye and primary skin irritation of anti- perspirant emulsions. The cetyl alcohol urea complex was claimed (25) to have mild anti-irritant activity es. certain dishwashing detergent components. l)iethyl Phthalate The author has found that mixing perfume oil with equal parts of diethyl phthalate (before extending with alcohol) yields colognes exhibiting lower eye irritation scores than those resulting from simple dilution with alcohol alone. qualities of iodine. PVP in this case. in the patent. Eracol E607 This cationic surfactant (N-caproyl colaminoformyl methyl pyr- idinium chloride produced by Witco Chemical Co.) is the preferred example of a patent (6) covering germicidal iodine compositions which do not exhibit the characteristic skin irritation, sensitizing or toxic The E607 seems to act in a manner similar to Data substantiating these claims are not presented Ethanolamine This compound was found to be active (2( 9 in inhibiting the in- flammatory response normally produced in rats by implanting cultures of micrococcus pyogenes ear. aureus. Glycogen Opdyke (13), in a paper on the "accommodation phenomenon," discussed the appearance of glycogen-bearing cells in skin which has