PROPERTIES OF JOJOBA OIL 381 Table II Summary of HRIPT Results Test article Results Comments Jojoba oil (lot AJA-PN) Jojoba oil (lot AJA-SR) Hydrogenated jojoba oil (lot FEED25) 1.01% (one subject) exhibited mild reaction (grade 1). All others showed no visible reaction (grade 0). 2.04% (two subjects) exhibited mild reaction. All others showed no visible reaction. 2.04% (two subjects) exhibited mild reaction. All others showed no visible reaction. Dermal response of subject with mild reaction subsided to grade 0 at 96-hour assessment point. Dermal response of subject 1 with mild reaction subsided to grade 0 at 96-hour assessment point. Dermal response of subject 2 exhibited a grade 1 dermal response at 96-hour assessment point. Dermal response of both subjects with mild reaction subsided to grade 0 at 96-hour assessment point. conditions of this study, refined, pure, and hydrogenated jojoba oil did not exhibit significant identifiable phototoxic potential when compared with the negative control. Table III summarizes these results. COMEDOGENICITY STUDY RESULTS Twenty five healthy subjects, of age range 18-60 years, were enrolled in this study. Following four weeks of exaggerated topical application with jojoba oil (both refined and Table III Summary of Phototoxicity Results Comments after 24 Comments after 72 Test article Results hours hours Jojoba oil (lot 11.76% (2 test sites) 0% non-irradiated test Erythema of both sites AJA-PN) exhibited sites exhibited erythema resolved before 72-hour erythematous beyond 24-hour evaluation. reaction at 48-hour evaluation. evaluation. Jojoba oil (lot 5.88% (1 test site) 0% non-irradiated test Erythema of site AJA-SR) exhibited sites exhibited erythema resolved before 72-hour erythematous beyond 24-hour evaluation. reaction at 48-hour evaluation. evaluation. Hydrogenated jojoba 11.76% (2 test sites) 0% non-irradiated test Erythema of both sites oil (lot FEED25) exhibited sites exhibited erythema resolved before 72-hour erythematous beyond 24-hour evaluation. reaction at 48-hour evaluation. evaluation. Distilled water 5.88% (1 test site) 0% non-irradiated test 1 test site inadvertently (negative exhibited sites exhibited erythema overexposed. control) erythematous beyond 24-hour reaction at 48-hour evaluation. evaluation.

382 JOURNAL OF COSMETIC SCIENCE Table IV Summary of Comedogenicity Results Test article No. microcomedones p-Value vs positive p-Value vs negative 2 cm 2 (mean) control control Jojoba oil (lot AJA-PN) 2.40 Jojoba oil (lot AJA-SR) 1.84 Hydrogenated jojoba oil (lot FEED25) 2.08 Acetulan (positive control) 5.32 Patch only (negative control) 2.72 0.0O2 0.640 0.005 0.280 0.0001 0.300 0.007 0.007 -- pure) and hydrogenated jojoba oil, the average number of microcomedones per two- square-centimeter area was measured (Table IV). Results of the cyanoacrylate follicular biopsies revealed significantly less (p 0.05) microcomedone formation in jojoba oil and hydrogenated jojoba oil treated areas versus the positive control, Acetulan. Refined, pure, and hydrogenated jojoba oils did not differ significantly in their capacity to induce microcomedone formation compared to the negative control. DISCUSSION Three different jojoba oil preparations were tested in three different skin assays. None of these substances showed signs of inducing identifiable contact sensitization nor were they comedogenic. In the test for photoxicity, infrequent, slight erythema was elicited in the UV-treated test sites, but these reactions were transient, with resolution in virtually all cases by 72 hours. Furthermore, significant irritation was not elicited within test sites not receiving irradiation, further supporting the results of the HRIPT. Photosensitivity describes an abnormal or adverse cutaneous reaction to light energy (8). Photosensitizers can be administered either systemically or topically. Photosensitivity due to topical agents may be phototoxic, photoallergic, or a combination of the two. A combination of both types of reactions occurs frequently. Even though other methods have been reported for assessing the potential phototoxicity of given substances, the technique described by Kaidbey and Kligman was used here because of its sensitivity and specificity (9). Techniques for testing the potential comedogenicity of a given product include animal models such as the rabbit ear (10). However, Frank has pointed out that no evidence exists that the rabbit ear model is predictive of acnegenicity in humans (11). Histology of the affected skin area demonstrating the follicular canal and its epithelium can also be used to assess comedogenicity, but this procedure is considerably more invasive and time-consuming than the follicular biopsy used in this study. The results reported here suggest that the jojoba oils and hydrogenated jojoba oil tested in these studies may be useful in the preparation of future skin care products. REFERENCES (1) J. Wisniak, The Chemistry and Technology of Jojoba Oil (American Oil Chemists' Society, Champaign, IL, 1987), p. 43.