Handbook of cosmetic science and technology second edition

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edited by
Marc Paye
Colgate–Palmolive R & D
Milmort, Belgium
André O. Barel
Vrije Universiteit
Brussels, Belgium
Howard I. Maibach
University of California Hospital
San Francisco, California, U.S.A.
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Cover Illustration: Marianne Mahieu
Published in 2006 by
CRC Press
Taylor & Francis Group
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© 2006 by Taylor & Francis Group, LLC
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International Standard Book Number-10: 1-57444-824-2 (Hardcover)
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Preface
In 2001, we published the first edition of the Handbook of Cosmet ic Science and
Technology with 71 chapters written by leading experts in their field of cosmetology,
who have largely contributed to the international success of the Handbook.
Since publication, comments were collected from readers and reviewers to
detect improvements that could be added to this edition. Most feedback was highly
positive as illustrated by some of the foll owing: ‘‘ excellent overall coverag e of
most aspect of cosmetology ;’’ ‘‘ contains a lot of scientific information about
the physical properties of cosmetic ingredients ;’’ ‘‘ an excellent balance of
authors from major cosmetic houses and with many academic leaders coming from a

huge range of countries provides an international view of cosmetics ;’’ ‘‘ an exten-
sive and comprehensive index can be considered as a measure of the book’s value ’’
This feedback was highly appreciated a nd motivated us in continuing the adventure
and in initiating a second edition that, we hope, will receive the same success as the
first one.
Like in all first editions, a few improvements were suggested and were taken
into account; it was mainly to develop a more systematic chapter organization as
well as making some chapters more accessible and readable for nonexpert readers.
Furthermore, cosmetology is, today, a fast moving science with new ingredients,
new technologies, and changing regulations. Thus, it was necessary to publish a
second edition to remain an up-to-date and practical Handbook of Cosmetic Science
and Technology.
The objectives pursued with the second edition are multiple. Most chapters,
recognized as essential for the cosmetologist, were kept but simplified, reviewed
for overlapping wi th others, made more readable, and mainly updated with new
developments or new anticipated trends . Some chapters had to be largely revisited
such as in Part VI: Regulatory and Safety Considerations, that is probably the fastest
changing field. Many chapters were added to cover new ingredients and technologies
identified by the editors. That is mainly evident in Part III: Cosmetic Ingredients
where many new, active, and promising ingredients have emerged. Testing the pro-
ducts has also improved, in terms of physicochemistry as well as in cell culture mod-
els or in skin measuring techniques. Chapters were added or re-designed to reflect
such an evolution. Finally, some gaps in the first edition were filled with chapters
on additional product types, adding more emphasis on ethnic skin and its differences
in cosmetics requirement s.
iii
The editors are grateful to the authors, who contributed to the previous edition
and updated their chapters, and to the new authors who agreed to share their experi-
ences on emerging subjects, sometimes with unpublished information.
Finally, it is anticipated that future editions will benefit in the same way as this

edition, from readers’ suggested additions, deletions, and improvements.
Marc Paye
Andre
´
O. Barel
Howard I. Maibach
iv Preface
Contents
Preface . . . . . . . . iii
Contributors. . . . . xxiii
1. Introduction . . . . . . 1
Marc Paye, Andre
´
O. Barel, and Howard I. Maibach
PART I. TARGET ORGANS FOR COSMETIC PRODUCTS
2. The Microscopic Structure of the Epidermis and Its Derivatives . . . . 5
Joel J. Elias
References . . . . 13
3. Racial (Ethnic) Differences in Skin Properties . . . . . . 15
Naissan O. Wesley and Howard I. Maibach
Introduction . . . . 15
Transepidermal Water Loss . . . . 17
Water Content . . . . 22
Corneocyte Variability . . . . 26
Blood Vessel Reactivity . . . . 27
Elastic Recovery/Extensibility . . . . 31
pH Gradient . . . . 34
Lipid Content . . . . 34
Surface Microflora . . . . 38
Mast Cell Granules . . . . 39

Epidermal Innervation . . . . 39
Conclusion . . . . 40
References . . . . 42
4. The Human Periorbital Wrinkle . . 45
Ian Scott and Martin Green
Wrinkles as an Aspect of Aged Skin . . . . 45
Local Differences in the Wrinkle Compared
to Surrounding Skin . . . . 46
v
Computer Model of the Periorbital Wrinkle . . . . 48
Origin of the Aligned Collagen Layer . . . . 50
Implications for Treatment of Wrinkles . . . . 51
References . . . . 51
5. Filaggrin and Dry Skin . 53
Ian Scott
Introduction . . . . 53
Filaggrin Genotype as the Major Determinant
of Susceptibility to Dry Skin . . . . 54
The Life Cycle of Filaggrin . . . . 55
Filaggrin and the Natural Moisturizing Factor . . . . 56
Perspective on Profilaggrin and Filaggrin Functions . . . . 57
References . . . . 59
6. Hair . . . . . . . 61
Dominique Van Neste
Introduction: What Is Hair? . . . . 61
Where Does Hair Come From? . . . . 67
Clinical Hair Growth Evaluation Methods . . . . 70
Basics About Psychosocial Aspects of Hair . . . . 83
References . . . . 84
7. The Normal Nail . . . . . . 89

Josette Andre
´
Anatomy . . . . 89
Histology . . . . 90
Physicochemistry . . . . 95
Physiology . . . . 95
Aesthetics . . . . 96
References . . . . 96
PART II. COSMETIC VEHICLES
8. Main Cosmetic Vehicles . 99
Stephan Buchmann
Introduction . . . . 99
Function of Vehicles . . . . 99
Classification Systems of Vehicles . . . . 101
Description and Definition of Main Vehicles . . . . 104
Functional Design, Composition, and Resulting Effect . . . . 112
Preparation Methods . . . . 120
Characterization . . . . 120
References . . . . 122
vi Contents
9. Encapsulation to Deliver Topical Actives . . . 125
Joce
´
lia Jansen and Howard I. Maibach
Introduction . . . . 125
Design Aspects of a Vector . . . . 125
Properties of a Vector . . . . 131
Dermatological and Cosmetic Uses of Encapsulation . . . . 133
The Future of Encapsulation . . . . 139
References . . . . 140

10. Encapsulation Using Porous Microspheres . . 145
Jorge Heller, Subhash J. Saxena, and John Barr
Introduction . . . . 145
Porous Microspheres . . . . 146
Applications . . . . 148
Conclusions . . . . 153
References . . . . 153
11. Liposomes 155
Hans Lautenschla
¨
ger
Introduction . . . . 155
Phosphatidylcholine . . . . 155
Liposomes . . . . 157
Availability . . . . 160
Applications . . . . 160
The Future of Liposomal Preparations . . . . 162
References . . . . 162
12. Novel Liposomes . . . 165
Brian C. Keller
Introduction . . . . 165
Colloidal Organization . . . . 166
New Spontaneous, Thermodynamically Stable (STS)
Liposomes . . . . 167
Utility . . . . 170
Encapsulation Efficiency . . . . 171
Skin Penetration . . . . 172
Cosmetic Applications . . . . 172
Conclusion . . . . 173
References . . . . 173

13. Elastic Vesicles as Topical/Transdermal Drug Delivery Systems . . 175
Myeong Jun Choi and Howard I. Maibach
Introduction . . . . 175
Elastic Vesicles–Skin Interaction . . . . 176
Transfersomes . . . . 177
Contents vii
Effect of Type Surfactants and Concentration . . . . 178
Non-Phospholipid-Based Elastic Vesicles . . . . 180
Ethosomes . . . . 181
Action Mechanism of Elastic Vesicles on Penetration . . . . 183
Conclusions . . . . 185
References . . . . 185
14. Topical Delivery by Iontophoresis . 189
Ve
´
ronique Preat and Valentin Wascotte
Introduction . . . . 189
Iontophoresis . . . . 189
Mechanisms of Iontophoretic Transport . . . . 190
Parameters Affecting Iontophoretic Delivery . . . . 191
Effects of Iontophoresis on the Skin: Safety Issues . . . . 192
Topical Delivery of Drugs and Cosmetics by Iontophoresis . . . . 194
Conclusions . . . . 195
References . . . . 196
15. Using Iontophoresis to Enhance Cosmetics Delivery . . . 201
Dov Tamarkin
Introduction . . . . 201
Delivering Actives to the Skin . . . . 201
Iontophoresis . . . . 202
Influence of the Energy Source . . . . 203

Influence of the Formulation . . . . 204
Electrolytes in the Formulation . . . . 205
Examples of Cosmetic Iontophoresis . . . . 205
Iontophoresis Devices . . . . 207
Conclusion . . . . 208
References . . . . 208
16. Cosmetic Patches . . . . . 211
Spiros A. Fotinos
Introduction . . . . 211
History and Evolution . . . . 211
Borders Between Pharmaceutical and Cosmetic Patches . . . . 212
Applications of Cosmetic Patches . . . . 212
Differences Between Classical Cosmetic Forms
and Patches . . . . 213
Development of Cosmetic Patches . . . . 213
Types and Configuration . . . . 214
Structural Components of the Cosmetic Patches . . . . 216
Production Steps . . . . 219
Regulatory Issues . . . . 219
Future Trends . . . . 220
viii Contents
PART III. COSMETIC INGREDIENTS
17. Antibacterial Agents and Preservatives . . . . . 223
Franc¸oise Siquet and Michel J. Devleeschouwer
Introduction . . . . 223
Antibacterial Products . . . . 225
Methods to Demonstrate Antimicrobial Product Efficacy . . . . 226
Preservation and Preservative Systems . . . . 228
References . . . . 230
18. Colorants . 233

Gisbert Ottersta
¨
tter
References . . . . 245
19. Skin Feel Agents . . . 247
Germaine Zocchi
Introduction . . . . 247
Emollients and Refatteners . . . . 248
Humectants . . . . 254
Polymers . . . . 255
Surfactants . . . . 260
Exfoliating Agents . . . . 262
Conclusions . . . . 262
References . . . . 263
20. Hydrating Substances . . . . . . . . . 265
Marie Lode
´
n
Introduction . . . . 265
Butylene Glycol . . . . 266
Glycerin . . . . 268
Hyaluronic Acid . . . . 269
Lactic Acid . . . . 270
Panthenol . . . . 271
PCA and Salts of PCA . . . . 272
Propylene Glycol . . . . 273
Proteins . . . . 274
Sorbitol . . . . 274
Urea . . . . 275
Conclusions . . . . 276

References . . . . 276
21. Ceramides and Lipids 281
B. B. Michniak and P. W. Wertz
Historical Perspectives . . . . 281
Ceramides from Epidermis . . . . 282
Lipids from Other Keratinized Tissues . . . . 285
Contents ix
Commercially Available Ceramides . . . . 286
Future Directions . . . . 286
References . . . . 287
22. Silicones—A Key Ingredient in Cosmetic and Toiletry Formulations 289
Janet Blakely and Isabelle Van Reeth
Unique Materials . . . . 289
Siloxane Backbone . . . . 289
Pendant Organic Groups . . . . 290
Key Ingredients in the Cosmetics and Toiletries Industry . . . . 290
Skin Care, Sun Care, and Decorative Products . . . . 292
Hair Care Products . . . . 295
Longer Lasting Permanent Wave and Coloring Products . . . . 297
Antiperspirant and Deodorant Products . . . . 297
References . . . . 297
23. UV Filters . . . 299
Stanley B. Levy
Introduction . . . . 299
Definitions . . . . 299
History . . . . 300
Regulatory . . . . 300
Mechanism of Action . . . . 304
Nomenclature . . . . 304
Individual UV Filters . . . . 304

UVB . . . . 304
UVA . . . . 307
Adverse Reactions—Toxicity . . . . 308
Conclusion . . . . 309
References . . . . 310
24. Skin Whitening: Ellagic Acid . . . . 313
Yoshimasa Tanaka
General Properties . . . . 313
In Vitro Studies . . . . 313
Animal Studies . . . . 314
Effect on Human Skin . . . . 316
References . . . . 318
25. Skin Whitening: New Hydroquinone Combination . . . . 319
Leslie S. Baumann and Lucy K. Martin
Disorders of Pigmentation . . . . 319
Other Pigmentation Disorders . . . . 320
A New Prescription Combination Therapy—Triluma . . . . 322
Summary . . . . 323
References . . . . 324
x Contents
26. Alpha Hydroxy Acids . . . . . . . . . 327
M. Carrera, G. Primavera, and E. Berardesca
References . . . . 331
27. Surfactants 333
Takamitsu Tamura
Solution Properties of Surfactants . . . . 333
Foaming Properties of Surfactants . . . . 337
Adsorption of Surfactants . . . . 340
References . . . . 343
28. Classification of Surfactants . . . . . 347

Louis Oldenhove de Guertechin
Introduction . . . . 347
Ionic Surfactants . . . . 347
Nonionic Surfactants . . . . 359
Nonhydrocarbon Specialty Surfactants . . . . 365
Further Reading . . . . 366
29. Anti-Irritants for Surfactant-Based Products . . . . . . . . . . . . . . . . . . 369
Marc Paye
Anti-Irritation by Using Only Mild Surfactants . . . . 370
Anti-Irritation by an Appropriate Combination
of Surfactants . . . . 370
Anti-Irritation by Polymers or Proteins/Peptides . . . . 371
Anti-Irritation by Refattening Agents . . . . 371
Anti-Inflammatory Effect . . . . 372
Antioxidants . . . . 372
Antisensory Irritation . . . . 372
Magnesium Is Not an Anti-Irritant for Surfactants . . . . 374
Conclusion . . . . 375
References . . . . 375
30. Seawater Salts: Effect on Inflammatory Skin Disease: An Overview 377
Ivy Lee and Howard I. Maibach
Seawater . . . . 377
Cations . . . . 378
Anions . . . . 383
References . . . . 383
31. Antioxidants . . . . . . 385
Stefan U. Weber, Claude Saliou, Lester Packer, and John K. Lodge
Introduction . . . . 385
Vitamin E . . . . 386
Vitamin C . . . . 387

Thiol Antioxidants . . . . 388
Contents xi
Polyphenols . . . . 389
The Antioxidant Network . . . . 390
Regulation of Gene Transcription by Antioxidants . . . . 392
Perspectives . . . . 392
References . . . . 393
32. Dexpanthenol . 399
Ehrhardt Proksch and Jens-Michael Jensen
Introduction . . . . 399
Biophysiology and Absorption . . . . 399
Modes of Administration . . . . 399
Indications and Clinical Applications . . . . 400
Side Effects, Contra-indications, and Product Safety . . . . 403
Conclusion . . . . 403
References . . . . 404
33. Hair Conditioners . . . . . 407
Charles Reich, Dean Su, and Cheryl Kozubal
Introduction . . . . 407
Conditioning and the Hair Fiber Surface . . . . 407
Commercial Conditioners . . . . 411
Conclusion . . . . 421
References . . . . 421
PART IV. COSMETIC PRODUCTS
34. Skin Care Products . . . . 427
Howard Epstein
An Overview of Emulsion-Based Skincare Products . . . . 427
Formulating Hydrating Creams and Lotions . . . . 429
Oil-in-Water Emulsions . . . . 430
Other Ingredients . . . . 433

Skin Care Emulsions for the Aging Population . . . . 435
Formulating for Immediate Improvement in Appearance and
Texture of Skin . . . . 436
Future Formulation Challenges . . . . 439
References . . . . 439
35. Antiwrinkle Products . . . 441
William J. Cunningham
Introduction . . . . 441
Background . . . . 441
Prevention of Wrinkles of Photoaging . . . . 442
Substantiation of Antiwrinkle Claims . . . . 442
Representative Products for Wrinkles . . . . 443
xii Contents
Summary and Conclusions . . . . 445
References . . . . 446
36. Skin Care Products: Artificial Tanning . . . . 449
Stanley B. Levy
Introduction . . . . 449
History . . . . 449
Chemistry . . . . 450
Formulation . . . . 450
Mechanism of Action . . . . 451
Application . . . . 451
Additives . . . . 452
Sunscreen Activity . . . . 452
Indications . . . . 453
Safety . . . . 453
Alternative Tanning Agents . . . . 453
Conclusion . . . . 454
References . . . . 454

37. Skin-Whitening Products . . . . . . . 457
Hongbo Zhai and Howard I. Maibach
Hydroquinone (1,4-Dihydroxybenzene) . . . . 457
Kojic Acid . . . . 460
Ascorbic Acid (Vitamin C) and Its Derivatives . . . . 460
Other Agents . . . . 461
Conclusions . . . . 461
References . . . . 461
38. Anticellulite Products and Treatments . . . . . 465
Andre
´
O. Barel
Introduction . . . . 465
Clinical, Visual, and Tactile Symptoms of Cellulite . . . . 465
Etiology of Cellulite . . . . 466
Histological Description of Adipose Tissues in Women . . . . 467
Description of the Different Stages of Lipodystrophy
of Fat Tissues . . . . 467
Objective Evaluation of the Symptoms of Lipodystrophy
of the Skin . . . . 468
Description and Validation of the Different Bioengineering
Measurements Used for Objective Evaluation of Cellulite . . . . 469
Treatments of Cellulite . . . . 471
Critical Review of Recent Clinical Anticellulite Studies . . . . 473
Conclusions . . . . 475
References . . . . 476
Contents xiii
39. Skin Cleansing Bars . . . 479
Joshua B. Ghaim and Elizabeth D. Volz
Introduction . . . . 479

What Is Soap? . . . . 479
Soap Raw Materials . . . . 480
Soap Phases . . . . 481
Soap Base Composition and Performance . . . . 482
Additives . . . . 482
Soap Making/Manufacturing Process . . . . 485
Formulations: Regular and Translucent Soaps, Combars, Syndets,
and Specialty Soaps . . . . 487
Bar Soap Performance Evaluations . . . . 489
References . . . . 492
40. Skin Cleansing Liquids . . 493
Daisuke Kaneko and Kazutami Sakamoto
Introduction . . . . 493
Surfactant-Type Skin Cleansers . . . . 495
Solvent-Type Skin Cleansers . . . . 499
Conclusion . . . . 501
References . . . . 502
41. Hair Cosmetics 505
Leszek J. Wolfram
Introduction . . . . 505
The Structure and Properties of Hair . . . . 505
Shampoos: General Comments . . . . 507
Hair Conditioners . . . . 512
Hairdressings . . . . 513
Concluding Remarks . . . . 526
References . . . . 527
42. Oral Care Products . . . . 529
Abdul Gaffar
The Teeth and Oral Environment . . . . 529
Dental Diseases Worldwide . . . . 533

Mouthwash . . . . 551
Strategy for Clinical Studies in Oral Care Products . . . . 551
Future Trends . . . . 552
References . . . . 552
43. Decorative Products . . . . 555
Mitchell L. Schlossman
Introduction . . . . 555
Color . . . . 555
Color Chemistry and Manufacture . . . . 558
xiv Contents
Make-Up Technology . . . . 567
Make-Up Formulary . . . . 582
References . . . . 591
44. Cosmetics for Nails . 593
Douglas Schoon and Robert Baran
Evaporation Coatings . . . . 593
Polymerizing Coatings . . . . 594
References . . . . 596
45. Antiperspirants . . . . 597
Jo
¨
rg Schreiber
Introduction . . . . 597
Biology of Sweat Glands in the Human Axilla . . . . 597
Antiperspirants . . . . 598
Drug-Delivery Systems and Application Forms
for Antiperspirant Actives . . . . 600
Future Trends . . . . 607
References . . . . 607
46. Deodorants 611

Jo
¨
rg Schreiber
Introduction . . . . 611
Biology of the Underarm Microflora . . . . 611
Deodorants . . . . 612
Drug-Delivery Systems and Application Forms
for Deodorant Actives . . . . 616
Future Trends . . . . 619
References . . . . 619
47. Cosmetics for Men . 623
Jens Treu and Peter Maurer
Introduction . . . . 623
Shaving . . . . 624
Aftershave Products . . . . 632
Face Care for Men . . . . 635
Conclusion . . . . 639
References . . . . 639
48. Baby Care 641
Uwe Scho
¨
nrock
Introduction . . . . 641
The Development of Baby Skin . . . . 641
The Physiology of Baby Skin . . . . 642
Frequent Skin Problems in Newborns . . . . 643
The Care of Baby Skin . . . . 644
Quality Management in Baby Care . . . . 646
Contents xv
Summary . . . . 647

References . . . . 647
49. Cosmetics for the Elderly 649
Uwe Scho
¨
nrock
Introduction . . . . 649
Age-Associated Changes in Human Skin: Morphological and
Histological Changes . . . . 649
The Cosmetic Care of Elderly Skin . . . . 650
Conclusions . . . . 652
References . . . . 652
PART V. TESTING OF COSMETIC PRODUCTS
50. Stability Testing of Cosmetic Products . . . . . 655
Perry Romanowski and Randy Schueller
Introduction . . . . 655
Practical Definition of Stability Testing . . . . 655
Useful Information Provided by Stability Testing . . . . 656
Stability Test Design . . . . 657
Situations that Require Stability Testing . . . . 660
Formula-Related Reasons for Stability Testing . . . . 660
General Considerations Related to Formula Modification . . . . 664
Nonformula-Related Reasons . . . . 665
Conclusion . . . . 666
References . . . . 666
51. Stability Control: Microbiological Tests . . . . 667
Michel J. Devleeschouwer and Franc¸oise Siquet
Microbiological Control of Raw Materials . . . . 667
Challenge Test for the Efficacy of Preservation . . . . 671
Determination of Water Availability or A
w

674
Culture Media, Neutralizing Solution, and Buffers . . . . 675
References . . . . 678
52. In Vitro Tests for Skin Irritation . . 683
Michael K. Robinson and Mary A. Perkins
Introduction . . . . 683
Skin Corrosion Testing . . . . 684
Skin Irritation Testing . . . . 687
Discussion . . . . 689
References . . . . 690
53. Reconstructed Corneal and Skin Models . . . 695
Klaus R. Schro
¨
der
Reconstructed Corneal Models . . . . 695
References . . . . 703
xvi Contents
54. In Vitro Reconstructed Human Skin and Skin Organ Culture Models Used
in Cosmetic Efficacy Testing . . . . . 707
Alain Mavon
Introduction . . . . 707
Skin Equivalents Used in Cosmetic Efficacy Testing . . . . 708
Examples of Cosmetic Efficacy Testing Using
In Vitro Skin Models . . . . 712
Conclusion . . . . 716
References . . . . 717
55. Squamometry: A Sensitive Testing Approach 721
Ve
´
ranne Charbonnier, Marc Paye, and Howard I. Maibach

Introduction . . . . 721
SQM: Principle . . . . 722
SQM and Skin Dryness . . . . 723
SQM and Skin Hydration . . . . 724
SQM and Skin Compatibility to Surfactant-Based
Solutions . . . . 725
Conclusion . . . . 729
References . . . . 730
56. Tests for Sensitive Skin . . . . . . . . 733
G. Primavera, M. Carrera, and E. Berardesca
Introduction . . . . 733
Epidemiologic Studies . . . . 733
Clinical Parameters . . . . 735
Tests for Sensitive Skin . . . . 735
Conclusions . . . . 741
References . . . . 741
57. Tests for Skin Hydration . . . . . . . 745
Bernard Gabard
Introduction . . . . 745
A Clinical Evaluation: The Regression Method . . . . 745
Incorporating Bioengineering Methods . . . . 746
Conclusion . . . . 750
References . . . . 751
58. Tests for Skin Protection: Barrier Effect . . . 753
Hongbo Zhai and Howard I. Maibach
In Vitro Methods . . . . 753
In Vivo Methods . . . . 754
Conclusions . . . . 755
References . . . . 758
Contents xvii

59. Tribological Studies on Skin: Measurement of the Coefficient of Friction
Raja K. Sivamani, Gabriel Wu, Howard I. Maibach, and Norm V. Gitis
Introduction . . . . 761
Skin Friction Coefficient Values . . . . 764
Conclusion . . . . 772
References . . . . 772
60. Anti-Itch Testing (Antipruritics) . . 775
Hongbo Zhai and Howard I. Maibach
Introduction . . . . 775
Methodologies . . . . 775
Conclusion . . . . 779
References . . . . 779
61. Evaluation Methods for Hair
Removal Efficacy . . . . . 781
Michiel E. Roersma and Joyce H. D. M. Westerink
Introduction . . . . 781
Methods for Hair Removal . . . . 781
Experimental Testing of Hair Removal Efficacy . . . . 783
Computer Simulation of Hair Removal Efficacy . . . . 787
Concluding Remarks . . . . 789
References . . . . 789
62. Skin Lipid Structure Measured by Electron Paramagnetic
Resonance . . . 793
Kouichi Nakagawa
Introduction . . . . 793
EPR Apparatus . . . . 794
EPR of Nitroxide Spin Probe . . . . 794
Spin Probe Lineshapes Owing to Molecular Motions . . . . 795
Spin Probes (or Spin Labels) . . . . 795
Conventional Order Parameter (S) 796

Order Parameter (S
0
) by the EPR Simulation . . . . 797
Conventional Order Parameter and Order Parameter by
Simulation Method . . . . 797
Other Applications of EPR Method . . . . 799
Summary and Future Prospects . . . . 799
References . . . . 800
63. Effects of Occlusion on Human Skin . . . . . . 803
Nicholas Golda, John Koo, and Howard I. Maibach
Background . . . . 803
Results . . . . 803
Discussion . . . . 810
Conclusions . . . . 812
References . . . . 812
xviii Contents
PART VI. REGULATORY AND SAFETY CONSIDERATIONS
64. Definition of Cosmetics . . . . . . . . 815
Stanley R. Milstein, Allen R. Halper, and Linda M. Katz
Introduction . . . . 815
Cosmetics in History . . . . 815
Statutory Definition of Cosmetics . . . . 816
Cosmetics that Are Also Drugs: The Intended Use Doctrine . . . . 817
The Cosmetic/Drug Distinction: The Role of the Intended
Use Doctrine in FDA Assignment of Regulatory Category
(Trade Correspondence) . . . . 821
The Alpha Hydroxy Acid (AHA) Situation . . . . 826
Cosmeceuticals, Cosmetic Therapeutics, and Other Proposed
Definitions . . . . 827
References . . . . 828

65. Regulatory Requirements for the Marketing of Cosmetics in the
United States . . . . . 833
Stanley R. Milstein, Allen R. Halper, and Linda M. Katz
Scope . . . . 833
Basic U.S. Legal Structure for Cosmetics . . . . 833
Basic U.S. Regulatory Structure for Cosmetics . . . . 835
References . . . . 854
66. Legislation in Japan 861
Mitsuteru Masuda and Fusae Harada
Regulatory Environment . . . . 861
Cosmetics . . . . 862
Quasidrugs . . . . 864
Cosmetics in the Future . . . . 866
Quasidrugs in the Future . . . . 867
References . . . . 867
67. EEC Cosmetic Directive and Legislation
in Europe . 869
Rene
´
Van Essche
The Laws of the Member States Relating to Cosmetic Products
and the 6th Amendment . . . . 869
Implementation of the European Directive on Cosmetic Products
in the Different Member States of the European Union . . . . 874
References . . . . 877
68. Introduction to the ‘‘Proof of Claims’’ . . . . . 879
Marc Paye and Andre
´
O. Barel
Regional Requirements . . . . 879

Categories of Claims . . . . 883
Contents xix
Type of Support . . . . 883
Conclusion . . . . 886
References . . . . 887
69. Safety Terminology . . . . 889
Ai-Lean Chew and Howard I. Maibach
Introduction . . . . 889
Contact Dermatitis . . . . 889
Irritant Contact Dermatitis (Irritation) . . . . 889
Allergic Contact Dermatitis . . . . 890
Photoirritant Contact Dermatitis
(Photoirritation/Phototoxicity) . . . . 891
Photoallergic Contact Dermatitis . . . . 891
Contact Urticaria Syndrome . . . . 891
Acnegenicity . . . . 892
Sensitive Skin . . . . 892
Bibliography . . . . 893
References . . . . 894
70. Principles and Mechanisms of Skin Irritation 895
Sibylle Schliemann-Willers and Peter Elsner
Introduction . . . . 895
Molecular Mechanisms of Skin Irritancy . . . . 895
Factors Predisposing to Cutaneous Irritation . . . . 896
Epidemiology . . . . 897
Clinical Types of ICD . . . . 898
References . . . . 901
71. In Vivo Irritation . . . . . . 905
Saqib J. Bashir and Howard I. Maibach
Introduction . . . . 905

Animal Models . . . . 907
Human Models . . . . 910
References . . . . 914
72. General Concepts of Skin Irritancy and Anti-Irritant Products . . . 917
Andre
´
O. Barel
Introduction . . . . 917
Irritancy and Skin Irritant Evaluation and Symptoms . . . . 918
Factors that Influence Skin Responsiveness
to Irritants . . . . 921
Cosmetic and Occupational Irritants . . . . 923
Strategy of Making Anti-Irritant Cosmetics . . . . 925
In Vivo Studies of the Anti-Irritation Properties of
Some Cosmetic Ingredients . . . . 927
References . . . . 929
xx Contents
73. Ethnicity as a Possible Endogenous Factor in Irritant Contact
Dermatitis: Comparing the Irritant Response Among Caucasians,
Blacks, and Asians . 933
Sara P. Modjtahedi and Howard I. Maibach
Introduction . . . . 933
Black vs. Caucasian Irritation Response . . . . 934
Asian vs. Caucasian Irritation Response . . . . 935
Conclusion . . . . 940
References . . . . 941
74. Principles and Practice of Percutaneous Absorption . . . 943
Ronald C. Wester and Howard I. Maibach
Introduction . . . . 943
Steps to Percutaneous Absorption . . . . 943

Methods for Percutaneous Absorption . . . . 944
Individual and Regional Variation . . . . 947
Vehicle Influence on Percutaneous Absorption . . . . 947
Skin Cleansing and Decontamination . . . . 948
Cosmetic Percutaneous Absorption and Toxicity . . . . 951
Cosmeceutics . . . . 952
Discussion . . . . 954
References . . . . 954
75. The Correlation Between Transepidermal Water Loss and Percutaneous
Absorption: An Overview . . . . . . . 957
Jackie Levin and Howard I. Maibach
Introduction . . . . 957
Exploring the Qualitative Reasoning for the Correlation Between
Percutaneous Absorption and TEWL . . . . 965
Conclusion . . . . 965
References . . . . 966
76. Allergy and Hypoallergenic Products . . . . . . 969
An E. Goossens
Introduction . . . . 969
Factors Contributing to Contact Allergic Reactions
to a Cosmetic Product . . . . 970
Correlations with the Location of the Lesions . . . . 972
The Nature of Cosmetic Allergens . . . . 972
Diagnosing Cosmetic Allergy . . . . 977
Hypoallergenic Products . . . . 977
Conclusion . . . . 978
References . . . . 978
Index . . . . 983
Contents xxi