The Validated Hypoallergenic Cosmetics Rating System: Its 30-year Evolution and Effect on the Prevalence of Cosmetic Reactions

Its 30-Year Evolution and Effect on the Prevalence of Cosmetic Reactions

Vermén M. Verallo-Rowell


Dermatitis. 2011;22(2):80-97. 

In This Article

"Validated Hypoallergenic" Rating System

The "validated hypoallergenic" (VH) rating system was initiated in 1988 to objectively rate cosmetic hypoallergenicity based on dermatologic reports of allergens causing CCD.[18] The VH rating system is numerical: the higher the number, the fewer allergens in the formulation and the more "hypoallergenic" (ie, the less likely to cause CCD) the product. The system works by (1) creating a VH list from reported top allergens that elicit positive patch-test reactions and (2) comparing the ingredients list of a cosmetic against the VH list to obtain a VH rating. The VH rating is expressed as "VH" followed by a minus sign, a number that indicates the quantity of allergens absent in the ingredients list of the cosmetic, and a forward slash (/) followed by a number that indicates the total number of allergens in the current VH list. The ideal hypoallergenic cosmetic would therefore have a VH rating that would be the same as the total number of allergens in the VH list (ie, it would contain "zero" allergens). The VH list is pegged on the sequential reports of top allergens that cause contact dermatitis by two large groups concerned with patch testing: the North American Contact Dermatitis Group (NACDG), which has published its reports since 1972, and the European Surveillance System for Contact Allergies (ESSCA), which has published its reports since 2002.

Patch testing was made famous in the 1950s in London[19] and by many other centers throughout Europe. By 1967, the European groups formed the International Contact Dermatitis Research Group (ICDRG), whose main goal was to provide a standardized procedure for patch-testing materials. By the 1980s, the ICDRG was able to reach its goals through extensive joint studies it initiated with many countries around the world.[20] The NACDG took over the task of allergen reporting in North America.[21] The group consists of 13 dermatologists (11 from the United States and 2 from Canada) who began multicenter studies in the 1970s with a standardized list of patch-test allergens.[22,23]

Multicenter cooperation by the working groups of the European Society of Contact Dermatitis led to the formal creation of ESSCA on October 10, 1996.[24] Both ESSCA and the NACDG have the following aims: (1) to recognize early the presence of (and kinds of exposure to) emerging allergens; (2) to compare reports from different countries and regions; (3) to standardize and quality-control patch testing in support of institutions involved in public health; and (4) to support postmarketing surveillance for product safety.[25] By January 2001, the multilingual European Standard series was distributed, mostly to European countries.[26] Studies conducted in 2002 to 2003 involved 10,511 study participants from 16 study centers.[27] In 2004, there were 11,643 participants from 31 centers,[28] and in 2005 to 2006, there were 19,793 participants aggregated from west, south, central, and northeast Europe.[29] Table 2 [29–40] lists the top allergens reported by the two groups and shows additions, omissions, and changes in concentration based on the results of preceding studies and literature reports of new allergens.

First: VH 10 Allergen List (1988–2002)

The top allergens in the first VH allergen list were collated from the results of patch-test studies using (1) the 20-allergen standard,[30] (2) vehicles and preservatives,[31] and (3) cosmetics[32] series of the American Academy of Dermatology as reported by the NACDG. Also analyzed were the results of a concordance study[33] done at VMV Skin Research Centre + Clinics (Makati, Philippines) on similar allergens from Chemotechnique (Malmo, Sweden) and Skin Sciences Laboratory, Inc, (Pasig, Philippines).[34] Of the 20 common allergens tested, 10 were considered to be present in cosmetics and made up the first VH list. With this VH-10 list, the highest possible (and most hypoallergenic) VH rating was VH-10/10 (indicating that all 10 top cosmetic allergens were absent from the product's ingredients list).

Second: VH 27 Allergen List (2003–2006)

In 1992 to 1994, the NACDG began to increase the number of test allergens.[35] Of 52 allergens first tested, 34 (65%) resulted in + patch-test reactions; 17 (50%) of those allergens produced at least one allergic reaction that was found to be clinically relevant to the present or past dermatitis. The next NACDG study, done on 50 allergens from 1994 to 1996, showed that the additional 30 allergens in its screening series were responsible for 47% of the allergic reactions of patients.[36] Of all patients tested, 12.4% may have had their disease misclassified as a nonallergic disorder, and an additional 34.4% of all tested patients would not have had their allergies fully defined. The NACDG's conclusion from the above reports (along with two additional studies done in 1996–1998[37] and 1998–2000,[38] all using 50 allergens) was that the increased number of allergens enhanced the usefulness of patch testing. Because 27 of the 50 allergens were present in cosmetics, the VH list increased in 2003 to reflect these 27 allergens, the rating VH-27/27 (indicating all 27 allergens to be absent in the ingredients list) being the most hypoallergenic.

VH 65 Allergen List (2007–2009)

From 2001 to 2006, the NACDG expanded its list to 65 allergens and published its results in 2004,[39] 2008,[40] and 2009.[41] Besides the allergens present in the cosmetic itself, there was the possibility of contamination of the cosmetic by allergens found in packaging and accessories for the following reasons: (1) packaging materials, accessories, and ingredients are purchased from anywhere in the world;[42] (2) contract manufacturing of cosmetic products (in part or as a whole) for extemporaneous, small, or private-label companies and even large prestige brands is a fairly common practice;[43] (3) piracy or imitation of products (more in aesthetic terms than in substance) continues to be practiced.[44]

Unlike food recalls, government recalls of cosmetics are relatively few. Besides contamination from the plausible sources cited above (ie, chemical, physical, and micro-biologic), cosmetics may be contaminated by chemicals used to adulterate or substitute for expensive ingredients. Allergens such as fragrance in common vessels used to mix both regular and hypoallergenic products can negate a fragrance-free claim for the latter. This is similar to "nutfree" food products that are cooked in vessels previously used for cooking other products with nuts. Plastic monomers and oligomers (phthalates) may contaminate products by leaching out from online filters, plastic seals, pipes, packaging, cleaning solutions, cooling waters, and machinery lubricants.[45] Drugs such as anesthetics,[46] antibiotics,[47] and steroids used as cosmetics or added to cosmetics have been reported.[48]

In 2007, all published NACDG top allergens were included in the VH list (no longer just the allergens commonly found in cosmetics). The most hypoallergenic rating was VH-65/65; all 65 top allergens, cosmetic (or considered cosmetic) and noncosmetic, are absent from the product's ingredients.

VH 76 Allergen List (2010)

In 2009, the NACDG started to study 70 allergens for the 2005–2006 period;[41] ESSCA continues to study 30 allergens.[29] Twenty-four of the 30 ESSCA allergens are part of the 70-allergen NACDG series. The 6 remaining ESSCA allergens plus the 70 NACDG allergens add up to the 76 allergens that make up the fourth and current VH 76 allergen list. The most hypoallergenic cosmetic is now rated VH-76/76. Cosmetics with more allergens listed as ingredients correspondingly have lower VH ratings and are less hypoallergenic. (In the cosmetic's ingredients list, the included allergens are referred to by asterisks and are underlined.) For example, a cosmetic containing "propylene glycol,*amidoamine,*ethylenediamine dihydrochloride*,three preservative allergens,*** and three fragrance allergens***" has nine of the top allergens present and is rated VH-67/76. Table 3[29,41] lists the 76 allergens alphabetically and cites their use in cosmetics, the products in which they are often found, possible ways they can contaminate (taint) products, and the chemicals with which they can cross-react.