JOURNAL OF COSMETIC SCIENCE 72 of henna with women may be advantageous where populations have suffered genocidal confl ict, women now dominate farming and entrepreneurial activity. As the market demand increases, as henna is bred for specifi c characteristics such as higher lawsone content, and as it is milled to higher quality standards, farmers who are smallholders in marginal areas with deteriorating conditions due to climate change will fi nd they can more easily stay on their land and provide for their families. MERGING HENNA, INDIGO, AND CASSIA INTO THE MODERN HAIR DYE INDUSTRY The users of home hair dye kits are the most vulnerable consumer group purchasers may be unaware that they are sensitized to oxidative hair dye, and the delayed hypersensitivity reaction to PPD may invalidate patch tests. Education of clients about the benefi ts of henna and ease of use is paramount. Henna is easily applied at home. If the safety, health, and naturalness of henna are marketed strongly, if educating clients about henna is made a priority, sensitized customers’ reluctance to change may be overcome. There is no reason for a salon to not use henna on individual clients or for a salon to become “henna only” to serve many sensitized clients by stylists who have become sensitized. PPD sensitization is no less than an epidemic than human immunodefi ciency virus (HIV) is, and they have many parallels. Recognition of the scope of the problem has been slow. A long latency period has exacerbated both, but the health effects are real, quantifi able, and inevitable in both. With HIV, there was great cultural resistance to acknowledging the epidemic, and great resistance to making the changes necessary to mitigate the risk. There is considerable resis- tance to henna in the cosmetology industry because of misinformation and inferior products. These problems can be corrected with education and improved product, and lives saved. If, in the 15 years between now and the time when the estimated crest of sensitized population begins to go gray, and henna, indigo, and cassia are improved through rigor- ous testing, plant breeding, and infrastructure improvement programs, client base loss for the oxidative hair dye industry can be avoided. Henna product lines can be developed which will benefi t not only the cosmetic industry: expanded henna, cassia, and indigo cultivation will stabilize farming in marginal regions and counteract desertifi cation through climate change. If the global henna supply must be increased to meet rising demand, alternate growing areas and improved plant breeding should be developed as quickly as possible. REFERENCES (1) G. T. Demirci, I. K. Altunay, G. Atis, and A. Kucukunal, Allergic contact dermatitis mimicking angio- edema due to paraphenylendiamine hypersensitivity: a case report, Cut. Ocul. Toxicol., 31, 250–252 (2012). (2) A. Broides, S. Sofer, and I. Lazar, Contact dermatitis with severe scalp swelling and upper airway com- promise due to black henna hair dye, Pediatr. Emerg. Care., 27 (8), 745–746 (2011). (3) P. J. Almeida, L. Borrego, E. Pulido-Melián, and O. González-Díaz, Quantifi cation of p-phenylenedi- amine and 2-hydroxy-1,4-naphthoquinone in henna tattoos, Contact Dermat., 66 (1), 33–37 (2012). (4) E. Özkaya, K. D. Yazganoglu, A. Arda, Z. Topkarci, and E. Erçag, The “henna stone” myth, Indian J. Dermatol. Venereol. Leprol., 79, 254–256 (2013). (5) K. A. Abdulla, and N. McD. Davidson, A woman who collapsed after painting her soles, Lancet, 348, 658 (1996).

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