Frequency of and trends in fragrance allergy over a 15-year period

Skin exposure to scented products used in daily life and fragrance contact allergy in the European general population - The EDEN Fragrance Study

BACKGROUND

Fragrances are widely used in scented products used in daily life with the potential to induce skin sensitization.

OBJECTIVE

To evaluate exposure to scented products and to explore associations between exposure and fragrance contact allergy.

METHODS

A cross-sectional study on individuals from 18 to 74 years of age, who were randomly selected from the general population in five European countries. A random sample (N = 3119) was patch tested and interviewed on exposure to scented products.

RESULTS

Female participants were strongly associated with exposure to scented products relative to male participants. Participants age 40 years and older showed an inverse association with exposure to scented products. Compared to Sweden, The Netherlands followed by Germany showed the highest overall exposure to scented products. Sensitive skin was associated with exposure to scented products and with fragrance allergy. In univariable regression analysis, exposure to leave-on products and to specific scented product subgroups was significantly associated with fragrance allergy.

CONCLUSION

Exposure to scented products depends primarily on sex and age. Female sex and sensitive skin are relevant indicators for developing fragrance allergy. Because aggregate exposure, especially to scented leave-on products, may enhance the prevalence of contact allergy to fragrances, further investigations into exposure amounts and frequencies is warranted.

Sensitization to Fragrance mix-1 in Patients with Contact Dermatitis in Nord-East of Italy: 1996–2016 Time Trend and Gender Effect

(1) Background: Fragrance sensitization is common in Italy and their constituents are used in many cosmetics and detergents. The objective of the study was to analyze the temporal trend of sensitivity to fragrance mix-1 in northeastern Italy and to evaluate gender differences; (2) Methods: From 1996 to 2016, 27,381 consecutive patients with suspected allergic contact dermatitis were patch tested. Individual characteristics were collected through a standardized questionnaire in six departments of dermatology or occupational medicine; (3) Results: The overall prevalence of sensitization to fragrance mix-1 was 7.3%; the prevalence was significantly higher in women (7.7%) than in men (6.3%). From 1996 to 2016, we observed an increase of this sensitization, ranging from 6.2% to 7.7% in males and from 7.2% to 9.1% in females; (4) Conclusions: Our study showed that contact allergy to fragrance mix-1 is important in both sexes and prevalence is increasing over time, despite the introduction of new fragrances with lower sensitization potential. There is the need to reduce the use of fragrances mix-1 to stop the increase of sensitization in exposed subjects.

Contact Allergy to Fragrances: In Vitro Opportunities for Safety Assessment

The majority of cosmetic products contain fragrances to make products more pleasant to the consumer, as we all like goods that smell nice. Unfortunately, contact allergy to fragrance compounds is among the most frequent findings in patients with suspected allergic contact dermatitis. In order to revert this and to reduce contact allergy to cosmetics, it is imperative to improve safety assessment of cosmetic products for skin sensitization. In the era of animal ban for cosmetic ingredients, this represents a challenge. Luckily, in the last decades, substantial progress has been made in the understanding of the mechanism of chemical-induced contact allergy and several in vitro methods are available for hazard identification. The purpose of this manuscript is to explore the possibility of non-animal testing for quantitative risk assessment of fragrance-induced contact allergy, essential for cosmetic products, which cannot be tested on animals.

Determination of fragrance allergens and their dermal sensitization quantitative risk assessment (QRA) in 107 spray perfumes

Cutaneous allergy occurs primarily as a result of using cosmetic, household, and laundry products available on the market that contain fragrances. The aim of this study was to develop a rapid and specific high-performance liquid chromatography with ultraviolet detection (HPLC-UV) method for quantification of 25 fragrance allergens (amyl cinnamyl alcohol, benzyl alcohol, benzyl benzoate, benzyl cinnamate, benzyl salicylate, citronellol, cinnamyl alcohol, citral, coumarin, eugenol, farnesol, geraniol, hydroxycitronellal, HICC (4-(4-hydroxy-4-methylpentyl)-3-cyclohexene-1-carboaldehyde), isoeugenol, isoeugenyl acetate, lilial (butyl phenyl methyl propional), limonene, linalool, methyl 2-octynoate, etc.). In addition, an exposure-based quantitative risk assessment (QRA) was performed to determine safe levels of fragrance ingredients in 107 perfumes. In 76 women's and 31 men's fragrances, 25 allergens were identified at concentrations ranging from undetectable (N.D.) to 8,997.68 mg/kg, and from N.D. to 17,352.34 mg/kg, respectively. An exposure-based sensitization QRA revealed that the ratios of acceptable exposure level (AEL) to consumer exposure level (CEL) of fragrance ingredients were greater than 1, suggesting an absence of skin sensitizing potential. However, the maximum level used in the exposure scenario was determined by the product purpose and application type, and AEL/CEL ratios of lilial, HICC, citral, isoeugenol, and methyl 2-octynoate analyzed in women's perfume were 0.53, 0.67 0.19, 0.13, and 0.57, respectively. As the ratios of AEL:CEL of these fragrance ingredients were below 1, the utilization of these potential skin sensitizers is not considered safe. Our findings indicate that the sensitization risk of allergens with AEL:CEL ratios below 1 detected in fragrances needs to be reduced to the appropriate human safety level for risk management.

Contact sensitization to limonene and linalool hydroperoxides in Spain: a GEIDAC* prospective study

BACKGROUND

Limonene and linalool are common fragrance terpenes widely used in cosmetic, household and hygiene products. Their primary oxidation products formed after air exposure, the hydroperoxides, have been recognized as important contact haptens.

OBJECTIVES

To investigate the prevalence of contact allergy to hydroperoxides of limonene (Lim-OOHs) and hydroperoxides of linalool (Lin-OOHs) in Spain, and to define the optimal concentration for screening in consecutive patients.

METHODS

Three different concentrations of Lim-OOHs (0.1%, 0.2% and 0.3% pet.) and Lin-OOHs (0.25%, 0.5% and 1.0% pet.) were simultaneously tested in 3639 consecutive patients at 22 departments of dermatology in Spain.

RESULTS

Lim-OOHs at 0.1%, 0.2% and 0.3% yielded positive patch test reactions in 1.4%, 3.4% and 5.1% of the tested patients, respectively; and Lin-OOHs at 0.25%, 0.5% and 1.0% yielded positive reactions in 1.3%, 2.9% and 4.9% of the tested patients, respectively. Few irritant (1.5-1.9%) and doubtful reactions (0.4-0.5%) to both terpene hydroperoxides were registered at the highest concentrations tested.

CONCLUSIONS

Lim-OOHs and Lin-OOHs can be considered as common causes of contact allergy, and their inclusion in an extended baseline patch test series therefore seems to be appropriate. The patch test preparations of Lim-OOHs 0.3% pet. and Lin-OOHs 1.0% pet. are useful tools for screening of contact sensitization.

In Situ Metabolism of Cinnamyl Alcohol in Reconstructed Human Epidermis: New Insights into the Activation of This Fragrance Skin Sensitizer

Chemical modification of epidermal proteins by skin sensitizers is the molecular event which initiates the induction of contact allergy. However, not all chemical skin allergens react directly as haptens with epidermal proteins but need either a chemical (prehaptens) or metabolic (prohaptens) activation step to become reactive. Cinnamyl alcohol has been considered a model prohapten, as this skin sensitizer has no intrinsic reactivity. Therefore, the prevailing theory is that cinnamyl alcohol is enzymatically oxidized into the protein-reactive cinnamaldehyde, which is the sensitizing agent. Knowing that reconstructed human epidermis (RHE) models have been demonstrated to be quite similar to the normal human epidermis in terms of metabolic enzymes, use of RHE may be useful to investigate the in situ metabolism/activation of cinnamyl alcohol, particularly when coupled with high-resolution magic angle spinning nuclear magnetic resonance. Incubation of carbon-13 substituted cinnamyl derivatives with RHE did not result in the formation of cinnamaldehyde. The metabolites formed suggest the formation of an epoxy-alcohol and an allylic sulfate as potential electrophiles. These data suggest that cinnamyl alcohol is inducing skin sensitization through a route independent of the one involving cinnamaldehyde and should therefore be considered as a skin sensitizer on its own.

Oxidized limonene and oxidized linalool - concomitant contact allergy to common fragrance terpenes

BACKGROUND

Limonene and linalool are common fragrance terpenes. Both oxidized R-limonene and oxidized linalool have recently been patch tested in an international setting, showing contact allergy in 5.2% and 6.9% of dermatitis patients, respectively.

OBJECTIVE

To investigate concomitant reactions between oxidized R-limonene and oxidized linalool in consecutive dermatitis patients.

METHODS

Oxidized R-limonene 3.0% (containing limonene hydroperoxides 0.33%) and oxidized linalool 6% (linalool hydroperoxides 1%) in petrolatum were tested in 2900 consecutive dermatitis patients in Australia, Denmark, Singapore, Spain, Sweden, and the United Kingdom.

RESULTS

A total of 281 patients reacted to either oxidized R-limonene or oxidized linalool. Of these, 25% had concomitant reactions to both compounds, whereas 29% reacted only to oxidized R-limonene and 46% only to oxidized linalool. Of the 152 patients reacting to oxidized R-limonene, 46% reacted to oxidized linalool, whereas 35% of the 200 patients reacting to oxidized linalool also reacted to oxidized R-limonene.

CONCLUSIONS

The majority of the patients (75%) reacted to only one of the oxidation mixtures, thus supporting the specificity of the reactions. The concomitant reactions to the two fragrance allergens suggest multiple sensitizations, which most likely reflect the exposure to the different fragrance materials in various types of consumer products. This is in accordance with what is generally seen for patch test reactions to fragrance materials.

Fragrance allergic contact dermatitis

Fragrances are a common cause of allergic contact dermatitis in Europe and in North America. They can affect individuals at any age and elicit a spectrum of reactions from contact urticaria to systemic contact dermatitis. Growing recognition of the widespread use of fragrances in modern society has fueled attempts to prevent sensitization through improved allergen identification, labeling, and consumer education. This review provides an overview and update on fragrance allergy. Part 1 discusses the epidemiology and evaluation of suspected fragrance allergy. Part 2 reviews screening methods, emerging fragrance allergens, and management of patients with fragrance contact allergy. This review concludes by examining recent legislation on fragrances and suggesting potential additions to screening series to help prevent and detect fragrance allergy.

Air-oxidized linalyl acetate - an emerging fragrance allergen?

BACKGROUND

Linalyl acetate is a fragrance chemical that is prone to autoxidation. Exposure to linalyl acetate occurs through cosmetic products and essential oils, but is difficult to assess, as linalyl acetate is not labelled in the EU.

OBJECTIVE

To investigate the frequencies of contact allergy to oxidized linalyl acetate among dermatitis patients, and to investigate the autoxidation of linalyl acetate in terms of hydroperoxide formation and sensitization potency.

PATIENTS AND METHODS

Hydroperoxide formation in air-exposed linalyl acetate was determined with high-performance liquid chromatography. The sensitization potencies of hydroperoxides were determined with the local lymph node assay. One thousand seven hundred and seventeen patients were patch tested with oxidized linalyl acetate at 6.0% in petrolatum.

RESULTS

Of the patients, 2.2% showed positive reactions to oxidized linalyl acetate. Forty-three per cent of the positive patients also had positive patch test reactions to other fragrance markers. Linalyl acetate hydroperoxides were detected early in the autoxidation process, and accumulated to a concentration of 37% after 42 weeks of air exposure. The linalyl acetate hydroperoxides were classified as moderate sensitizers.

CONCLUSIONS

The frequency of positive reactions to oxidized linalyl acetate is comparable to that of previously studied oxidized fragrance terpenes. Oxidized linalyl acetate could thus be a common fragrance contact allergen.

Fragrance allergy and quality of life - development and validation of a disease-specific quality of life instrument

BACKGROUND

Fragrance allergy is a lifelong condition that may give rise to permanent or recurrent contact dermatitis and may affect quality of life (QoL). The effect on QoL has not yet been investigated, and no disease-specific QoL instrument for fragrance allergy exists.

OBJECTIVE

To develop and validate a disease-specific instrument to investigate QoL among fragrance-allergic subjects.

METHOD

A fragrance QoL instrument (FQL index) was developed on the basis of narratives from 68 fragrance-allergic subjects, and consisted of 13 items. It was tested in a postal survey among 1650 participants patch tested at Gentofte University Hospital (2000-2010). The survey included other QoL instruments [Dermatology Life Quality Index (DLQI) and Short Form 36 (SF36) version 2] and questions on eczema severity (response rate of 66%). A retest was conducted after 3-6 months (response rate of 72.5%).

RESULTS

The FQL index showed a significant and strong correlation with the DLQI (rS  = 0.70), and disease severity, but a weak correlation with SF36 [mental component summary score, rS  = - 0.22; physical component summary score, rS  = - 0.31]. Good reliability and responsiveness to changes in disease severity were seen.

CONCLUSION

The FQL index is a good instrument with which to investigate QoL in subjects with fragrance allergy. Good correlations with the DLQI and self-estimated disease severity were seen, and it showed good reliability, reproducibility and ability to distinguish changes in disease severity.

Contact allergies to potential allergens in patients with oral lichen lesions

OBJECTIVE

The aim of the present controlled study was to investigate a possible relationship between contact allergies to potential allergens and oral lichen lesions.

METHODS

Eighty-three patients with oral lichen lesions (OLL) and control groups of age- and gender-matched dermatitis patients (DP, n = 83) and patch-tested dermatitis patients randomly selected from files (PSFF, n = 319) were included in the study. OLL and DP groups were patch-tested epicutaneously and examined intraorally.

RESULTS

The frequencies of contact allergy to mercury and carvone were statistically higher in the OLL group than in the DP group. Surfaces of amalgam and composite restorations were statistically more frequent in the OLL group compared to the DP group. Contact allergy to nickel and colophony, the latter with a statistically significant difference, was more common in the DP group. The numerical difference found for nickel allergy was, however, not significant comparing the OLL and PSFF groups.

CONCLUSION

Contact allergy to mercury was overrepresented in patients with OLL and has been reported in previous studies, but the present finding of an overrepresentation of contact allergy to carvone in patients with oral lichen lesions has not been reported previously.

CLINICAL RELEVANCE

Carvone, in addition to mercury and gold, as previously suggested, can be one of the causative or maintenant factors for oral lichen lesions. Carvone-hypersensitive patients with oral lichen lesions should therefore avoid carvone-containing products for oral use.

Patch testing with fragrance mix II: results of the IVDK 2005-2008

BACKGROUND

The fragrance mix (FM I), established in 1977, detects the majority, but not all cases of contact allergy to fragrances. Based on European research 2002/2003, fragrance mix II (FM II) was developed to supplement FM I. In 2005, the German Contact Dermatitis Research Group (DKG) added FM II to their baseline series.

OBJECTIVES

To evaluate reactions to FM II and its constituents in routine patch testing.

METHODS

Retrospective data analysis of the Information Network of Departments of Dermatology (IVDK), 2005-2008, of patch test results with FM II and its constituents.

RESULTS

A total of 35 633 patients were patch tested with FM II as part of the DKG baseline series. Of these, 1742 (4.9%) reacted positively. Concomitant reactions to FM I were observed in 41.9% of the patients reacting to FM II. In 367 FM II-positive patients, a full breakdown test of the mix was performed. Of these, 47.7% reacted to hydroxyisohexyl 3-cyclohexene carboxaldehyde, 16.1% to citral, 11.4% to farnesol, 3.8% to hexyl cinnamal, 2.7% to coumarin, and 2.5% to citronellol.

CONCLUSIONS

FM II is an important screening and diagnostic tool to detect fragrance allergy. Hydroxyisohexyl 3-cyclohexene carboxaldehyde is the most important fragrance allergen in FM II.