JOURNAL OF COSMETIC SCIENCE 412 The method developed here is for total Pb. Our studies showed that variable amounts of Pb can be extracted depending upon experimental conditions such as analytical portion, acids used, temperature, decomposition procedure, etc. Consistent results could usually be obtained only by including HF in the digestion procedure. To illustrate this, fi ve lipstick lots and the composite were analyzed by digestion with HNO3 alone or with HNO3 + HF. Substantially higher values were obtained for three of the lots and the composite using HNO3 + HF compared to HNO3 alone. Pb values for two different lots of the same lipstick were equivalent by digestion with HNO3 alone or with HNO3 + HF (see C-4, lots a and b). Results reported by the Campaign for Safe Cosmetics (CSC), in which several of the same brands and shades of lipsticks were analyzed (2), are also listed in Table V. The CSC method used a 0.5-g portion, extraction with sulfuric and nitric acids, and ICP–MS analysis. Lot numbers were not reported by the CSC. Differences among values obtained by the three digestion techniques can be explained by the presence of mineral content in some formulations, as well as by the fact that Pb is easily precipitated as a sulfate after sulfuric acid is used in the CSC extraction. Mica, a mineral permitted as a color additive, which frequently contains small amounts of Pb (13), would require HF for complete dissolution. The use of sulfuric acid in the CSC ex- Table V Lead Content in Lipsticks by Validated Method and by Two Other Techniques Product Shade Lot FDA: HF + HNO3 (μg Pb/g) FDA: HNO3 (μg Pb/g) CSC (μg Pb/g) (lot #s unknown) A 1 a 1.40 b 1.20, 1.22 0.12, 0.56 c 3.06 1.90 d 3.05 B 1 Composite 2.91 0.29 0.02 a 2.38 A 2 a 2.24 0.03, 0.03 C 1 a 1.79 0.02, 0.02, 0.06 A 3 a 1.76 0.28 C 2 a 1.53 b 0.62, 0.68 0.50, 0.65 c 1.47 1.20 B 2 a 1.37 0.91 0.02 b 0.83, 0.81 C 3 a 1.21 0.19 B 3 a 1.04 0.02, 0.03 C 4 a 0.67 0.60 0.58 b 0.79 0.74, 0.80 D 1 a 0.55 0.02 D 3 a 0.48 0.03 D 2 a 0.43 0.02 E 1 a 0.33 0.09 C 5 a 0.23 0.12 F 1 a 0.17 0.12 G 1 a 0.15 0.02, 0.04 H 1 a 0.12 0.21 I 1 a 0.10 0.02, 0.03 J 1 a 0.09 0.02

DETERMINATION OF TOTAL LEAD IN LIPSTICK 413 traction method may have reduced the soluble Pb available for ICP–MS analysis, thus resulting in the lower values reported by the CSC. The FDA has not set specifi cations for Pb in cosmetics, except that color additives per- mitted as ingredients are usually limited to 20 μg Pb/g (20 ppm) (5). The Pb levels found in these lipsticks, determined by the validated method, are within the range that might be expected from lipsticks formulated with permitted color additives and other ingredi- ents prepared under good manufacturing practice (GMP) conditions. CONCLUSIONS Typical microwave-assisted HNO3 digestion produced low-biased, inaccurate values for some lipstick samples and one of the RMs. All of the lipsticks analyzed in this work con- tained detectable amounts of Pb when digested with HNO3 and HF. Some of the Pb in certain lipstick samples appears to be incorporated in the refractory mineral pigments, which require HF for complete digestion. Pb levels found by the FDA are within the range that might be expected from lipsticks formulated with permitted color additives and other ingredients prepared under GMP conditions. ACKNOWLEDGMENTS The authors thank Richard Jacobs of the FDA’s San Francisco District Lab for analyzing several lipsticks after a HNO3 extraction treatment. Nancy Hepp would like to thank Stephen Capar in the FDA’s Offi ce of Regulatory Science and his group for allowing her to use his laboratories, equipment, and instrumentation to do the studies, and for providing helpful guidance. She would also like to thank Fred Hurley for advice and for sharing knowledge of cosmetics and lipsticks. Finally, we are very grateful to representa- tives from several cosmetic companies and the industry trade group, the Personal Care Product Council, for cooperation in providing samples and information about testing, and to Stanley Milstein in the FDA’s Offi ce of Cosmetics and Colors for coordinating all involved parties. REFERENCES (1) “Lead Poisoning,” March 15, 2007 accessed August 2008, http://www.mayoclinic.com/health/lead- poisoning/FL00068/ DSECTION=causes. (2) “Campaign for Safe Cosmetics, A Poison Kiss: The Problem of Lead in Lipstick,” October 2007, ac- cessed October 2007, http://www.safecosmetics.org/your_health/poisonkiss.cfm. (3) R. Paige, “Dangerous Levels of Lead in Lipstick, Lip Gloss?,” May 17, 2006, accessed July 2008, http:// cbs2.com/consumer/Lipstick.Lip.Gloss.2.516979.html. (4) B. Thompson, “Is Lead Inside Lipstick,” July 24, 2006, accessed September 26, 2008, http://www. wpxi.com/print/9566833/detail.html. (5) Code of Federal Regulations (2008) Title 21 (U.S. Government Printing Offi ce, Washington, DC), Sec- tions 73, 74, and 82. (6) Federal Food, Drug, and Cosmetic Act, Chapter XI, as amended January 2004. (7) M. Okamoto, M. Kanda, I. Matsumoto, and Y. Miya, Fast analysis of trace amounts of lead in cosmetics by atomic absorption spectrophotometry, J. Soc. Cosmet. Chem., 22, 589–598 (1971). (8) K. D. Besecker, C. B. Rhoades, B. T. Jones, and K. W. Barnes, A simple closed-vessel nitric acid diges- tion method for cosmetic samples, Atom. Spectros., 19, 48–54 (1998).