Fragrance contact allergens in 5588 cosmetic products identified through a novel smartphone application

Contact sensitization to fragrance mix I and fragrance mix II among European dermatitis patients: A systematic review

BACKGROUND

Fragrance substances are a frequent cause of contact allergy worldwide. Fragrance exposure varies by sex, age and possibly country, influenced by cosmetic availability, environmental conditions and cultural practices.

OBJECTIVES

To systematically review and gather prevalence of sensitization to fragrance mix I (FM I) and fragrance mix II (FM II) in consecutively patch-tested European dermatitis patients.

METHOD

A total of 4134 publications on patch test results of European dermatitis patients, published from 1981 to 2022, were systematically reviewed according to a previously registered and published PROSPERO protocol.

RESULTS

Eighty-four eligible original articles were analysed. Overall prevalence of sensitization to fragrance mix I (FM I) was 6.81% (95% CI: 6.37-7.28), and FM II was 3.64% (95% CI: 3.3-4.01). Sensitization to FM I was most prevalent in Central and Eastern Europe and to FM II in Western Europe. No clear time trends were observed. Among paediatric dermatitis patients, sensitization prevalence for FM I and FM II was 4.09% (95% CI: 3.37-4.96) and 2.17% (95% CI: 1.53-3.07).

CONCLUSION

The frequency of positive patch test results for both FMI and FMII remains high. Sensitization is also prevalent among children. Enhanced regulation and labelling of cosmetic products play a vital role in averting exposure and sensitization to fragrance allergens.

Fragrance allergens in cosmetic products marketed for children in Denmark

BACKGROUND

Fragrances are among the most common contact allergens in children. Cosmetic products are the most frequent source of skin exposure.

OBJECTIVE

To investigate exposure to fragrance allergens among Danish children, based on a sample of 1179 cosmetic products marketed for children.

METHODS

Information regarding cosmetic products marketed to children was obtained using a non-profit smartphone application registry, with data from December 2015 to November 2022.

RESULTS

The number of validated products was 26  537, of which 1349 marketed for children. After elimination of duplicates, 1179 (4.4%) individual products remained. The majority 53.8% (634/1179) of the products were fragranced. The highest frequency of declared fragrances was found in 'Facial care'-products: 93.0% (80/86), of which 97.7% were lip balms. The highest number of labelled fragrances in one single product (n = 16) was found in a baby perfume. Fragrance mix I (FMI) or II (FMII) allergens were found in 25.3% (298/1179) of the products. Limonene and linalool were the two most frequently labelled fragrance allergens.

CONCLUSION

Children can be exposed to a vast number of fragrance allergens from scented cosmetic products. Allergens from FM I and FMII are widely used in cosmetic products marketed to children. Patch testing with FMI and FMII remains relevant in children.

Decision making in next generation risk assessment for skin allergy: Using historical clinical experience to benchmark risk

Our aim is to develop and apply next generation approaches to skin allergy risk assessment that do not require new animal test data and better quantify uncertainties. Quantitative risk assessment for skin sensitisation uses safety assessment factors to extrapolate from the point-of-departure to an acceptable human exposure level. It is currently unclear whether these safety assessment factors are appropriate when using non-animal test data to derive a point-of departure. Our skin allergy risk assessment model Defined Approach uses Bayesian statistics to infer a human-relevant metric of sensitiser potency with explicit quantification of uncertainty, using any combination of human repeat insult patch test, local lymph node assay, direct peptide reactivity assay, KeratinoSens™, h-CLAT or U-SENS™ data. Here we describe the incorporation of benchmark exposures pertaining to use of consumer products with clinical data supporting a high/low risk categorisation for skin sensitisation. Margins-of-exposure (potency estimate to consumer exposure level ratio) are regressed against the benchmark risk classifications, enabling derivation of a risk metric defined as the probability that an exposure is low risk. This approach circumvents the use of safety assessment factors and provides a simple and transparent mechanism whereby clinical experience can directly feed-back into risk assessment decisions.

Occurrence of Allergens in Cosmetics for Sensitive Skin

Sensitive skin is characterized by symptoms such as stinging and tingling in response to stimuli that usually do not cause unpleasant sensations. Epidemiological studies show that individuals with sensitive skin are more prone to developing skin allergies, although the link between both conditions is unknown. Aiming to evaluate the presence of allergens in facial-skin products for sensitive skin, a pool of 88 cosmetic products from international brands marketed in pharmacies and parapharmacies was analyzed. A list of allergens identified in product labels was compiled and grouped according to their function. Fragrances were the most common allergens, followed by skin-conditioning agents, surfactants, and preservatives. Fragrances presenting the highest use percentages were linalool, benzyl alcohol, geraniol, and citronellol. Overall, the majority of cosmetic formulations were absent of fragrance allergens, being present only in 7% of products. Other allergens were found in most products (95%). This finding should be interpreted with caution, since many of these compounds are rare sensitizers and studies demonstrating their risk for individuals with sensitive skin are lacking. With this study, useful information for health professionals is provided to support their advice and to help consumers choosing cosmetic products.

Limonene and linalool hydroperoxides review: pros and cons for routine patch testing

Limonene and linalool are among the most common fragrance terpenes used in products of everyday life. They are pre-haptens forming hydroperoxides (Lim-OOHs, Lin-OOHs) upon oxidation inducing frequent positive patch test reactions in patients with dermatitis. Still, they are not yet routinely tested in Europe. This review evaluates the patch testing experience with Lim-OOHs and Lin-OOHs by answering key questions such as whether hydroperoxide patch testing is warranted, understand difficulties or challenges related to the reading and interpretation of hydroperoxide patch test results with currently available material, assessing their relevance. Studies are increasingly pointing out to high percentages of positive reactions in patients consecutively patch tested with these oxidized products. An association between a positive clinical history and a strong patch test reaction has been described, but problems with doubtful/irritant reactions have also been reported. Considering the high frequencies of relevant positive reactions, the incorporation of Lim-OOHs 0.3% and Lin-OOHs 1% in the baseline series could be discussed and is maybe justified. Since exposure, sensitization and elicitation limits of Lim-OOHs and Lin-OOHs in the products still need to be better determined, an assessment of previous exposure, possible sensitizations and reactions may help to improve the clinical assessment. This article is protected by copyright. All rights reserved.

The association between rosacea and the condition of low tolerance to skincare of the facial skin: a case-control study in China

BACKGROUND

Patients with rosacea often complained of low tolerance to skincare.

AIM

To examine if the preexisted low tolerance to skincare is associated with rosacea the occurrence of the Chinese population.

METHODS

A retrospective case-control survey of 997 rosacea cases and 1012 skin-healthy controls was carried out in China. Low tolerance to skincare was evaluated based on the history of facial skin allergic reactions related to skincare in the past 5 years before the onset of rosacea. A comparative analysis was performed between the case and control groups by the chi-square test and the logistic regression analysis.

RESULTS

History of facial skin allergic reaction due to skin care products (OR = 5.110, 95% CI = 3.893-6.706) and skin care in beauty salons (OR = 3.002, 95% CI = 1.506-5.981) both presented a positive correlations with the occurrence of rosacea. Facial masks and cosmetics were two of the most common products causing facial allergic reaction. The OR values increased with the increased frequency of allergic reactions related to facial mask and cosmetics. In addition, the history of facial skin allergic reaction had a significantly associated with the severity of self-reported symptoms of rosacea including dryness, burning, stinging and itching.

CONCLUSIONS

The condition of low tolerance of the facial skin to skincare was closely associated with the occurrence of rosacea.

Comparison of a Barcode-Based Smartphone Application to a Questionnaire to Assess the Use of Cleaning Products at Home and Their Association with Asthma Symptoms

Household disinfectant and cleaning products (HDCPs) assessment is challenging in epidemiological research. We hypothesized that a newly-developed smartphone application was more objective than questionnaires in assessing HDCPs. Therefore, we aimed to compare both methods, in terms of exposure assessments and respiratory health effects estimates. The women of the SEPAGES birth cohort completed repeated validated questionnaires on HDCPs and respiratory health and used an application to report HDCPs and scan products barcodes, subsequently linked with an ingredients database. Agreements between the two methods were assessed by Kappa coefficients. Logistic regression models estimated associations of HDCP with asthma symptom score. The 101 participants (18 with asthma symptom score ≥1) scanned 617 different products (580 with available ingredients list). Slight to fair agreements for sprays, bleach and scented HDCP were observed (Kappa: 0.35, 0.25, 0.11, respectively). Strength of the associations between HDCP and asthma symptom score varied between both methods but all odds ratios (OR) were greater than one. The number of scanned products used weekly was significantly associated with the asthma symptom score (adjusted-OR [CI 95%]: 1.15 [1.00–1.32]). This study shows the importance of using novel tools in epidemiological research to objectively assess HDCP and therefore reduce exposure measurement errors.

Frequency of sensitization to the individual fragrances of fragrance mix I and II according to the factors included in the MOAHLFA index

BACKGROUND

Fragrances constitute the second most frequent cause of allergic contact dermatitis in Spain.

OBJECTIVES

To determine the rate of sensitization to the individual fragrances of fragrance mix (FM) I and FM II for each of the demographic and clinical factors included in the MOAHLFA (male, occupational dermatitis, atopic dermatitis, hand dermatitis, leg dermatitis, facial dermatitis, age) index.

METHODS

We conducted a 5-year retrospective study in 23 Spanish centres. We identified the patients who had undergone patch testing with a specific fragrance series after reacting positively to fragrance markers in a baseline series. We obtained the MOAHLFA index items in this population, then calculated for each demographic and clinical factor the frequencies of sensitization to the individual fragrances of FM I and FM II.

RESULTS

A specific fragrance series was patch tested in 1013 patients. The most frequent allergens in men, women, children, and retired people were Evernia prunastri (16%), geraniol (16.6%), isoeugenol (17.9%), and geraniol (22.4%), respectively. Citral (20.5%) and hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) (14.5%) were the most common allergens in occupational eczemas and were also associated with a large proportion of hand and facial dermatitis.

CONCLUSIONS

Frequency of sensitization to the individual fragrances of FM I and FM II varies with age, sex, affected body region, and history of occupational or atopic dermatitis.

Human biomonitoring in urine samples from the Environmental Specimen Bank reveals a decreasing trend over time in the exposure to the fragrance chemical lysmeral from 2000 to 2018

2-(4-tert-butylbenzyl)propionaldehyde (trade names, e.g. lysmeral or lilial) is a fragrance chemical frequently used in cosmetic products where it is labelled as Butylphenyl methylpropional. A recently developed LC-MS/MS method for the analysis of four lysmeral metabolites (tert-butylbenzoic acid (TBBA), lysmerol, lysmerylic acid, and hydroxy-lysmerylic acid) was applied to 329 urine samples from the Environmental Specimen Bank collected between 2000 and 2018. The two major metabolites TBBA and lysmerol were found in quantifiable concentrations in almost all samples in this study and correlated significantly. Hence, both analytes proved to be specific biomarkers indicating the broad exposure to lysmeral. A significant decline was found for TBBA and lysmerol for the monitored years with the most pronounced decrease from 2012 to 2015. The daily intake (DI) was used to evaluate potential health risks with respect to the derived no-effect level (DNEL) as a threshold for exposure of the general population. The median DI (1.63 μg/kg bw/d) and the 95th percentile (4.69 μg/kg bw/d) corresponded to 2.6% and 7.5% of the lowest DNEL (62.5 μg/kg bw/d for oral administration), respectively. Even though a decreasing trend in exposure was observed the data still calls for efforts to reduce the exposure towards lysmeral since metabolites of lysmeral were detected in nearly all samples and adverse effects cannot be excluded. Clearly, these results need to be substantiated by HBM campaigns in population representative samples like the German Environmental Survey in adults (GerES VI) to provide more robust data for the adult population.

Allergen Content of Best-Selling Ethnic Versus Nonethnic Shampoos, Conditioners, and Styling Products

BACKGROUND

Hair products are a potential cause of allergic contact dermatitis. There are limited data on the allergen content of ethnic hair products.

OBJECTIVE

To identify allergens unique to ethnic hair products (shampoos, conditioners, styling products) and provide a resource for low allergen hair care products for patients with ethnic hair types.

METHODS

The top 100 best-selling shampoos, conditioners, and styling products for ethnic and nonethnic hair products were determined from 3 major online retailers (Walmart, Target, Walgreens). Allergen was defined as presence on the 2017 American Contact Dermatitis Society Core 80 allergen list.

RESULTS

The 2017 American Contact Dermatitis Society Core 80 allergens were tabulated for ethnic and nonethnic shampoos, conditioners, and styling products. A list of low-allergen shampoos, conditioners, and styling products was identified. Fragrance was the most common allergen for ethnic shampoos, conditioners, and styling products. Other notable allergens included methylchloroisothiazolinone/methylisothiazolinone, formaldehyde releasers, cetyl steryl alcohol, tocopherol, decyl glucoside, sodium benzoate, and phenoxyethanol.

CONCLUSIONS

This study identifies important differences in allergens found in products marketed for ethnic hair compared with those marketed for nonethnic hair.

Use of Mobile Applications in Dermatology

Smartphones and applications related to the same are ubiquitous now. As dermatologists, we have a wide array of smartphone apps at our disposal which we can use to improve our practice in all aspects—clinical, academic, research, and administrative. This article provides an overview of available apps, tips on using apps—both general and specific for dermatology, as well as discusses the scientific validity of some of these apps and the future of smartphone apps in the context of dermatology.

Patch testing with purified and oxidized citronellol

BACKGROUND

Citronellol is a commonly used fragrance terpene included in fragrance mix II. As with many other fragrance terpenes, citronellol is susceptible to autoxidation. Citronellol hydroperoxides are formed in large amounts and are the only oxidation products identified as sensitizers in oxidized citronellol.

AIM

To compare frequencies of contact allergy to purified and oxidized citronellol and to investigate the pattern of concomitant reactions to fragrance markers of the baseline series, oxidized linalool, and oxidized limonene.

METHODS

A total of 658 dermatitis patients were patch tested with purified and oxidized citronellol at 2.0%, 4.0%, 6.0%, and 1.0%, 2.0%, 4.0%, 6.0% petrolatum, respectively. The irritant properties of purified and oxidized citronellol were studied before patch testing.

RESULTS

Few irritant reactions were observed in the pretest. Purified citronellol detected positive reactions in 0.15%-0.31% of patients, while oxidized citronellol detected positive reactions in 0.61%-4.5%. Among patients reacting to oxidized citronellol, 34%-50% showed concomitant reactions to fragrance markers of the baseline series and 75%-91% to oxidized linalool or oxidized limonene.

CONCLUSION

Oxidized citronellol detects more cases of contact allergy than purified citronellol, and these cases are not all detected using fragrance mix II. Patch testing with oxidized citronellol will add to the tools in the diagnosis of fragrance allergy.

Natural ingredients in cosmetic products-A suggestion for a screening series for skin allergy

BACKGROUND

Naturally derived cosmetic product ingredients of both plant and animal origin are being included increasingly in product formulations in order to cater to consumer preferences. They may be an overlooked cause of reactions to cosmetic products in some patients with dermatitis.

OBJECTIVES

To identify naturally derived cosmetic product ingredients with allergenic potential (type I and type IV) and propose a cosmetic screening test series.

METHODS

The study was conducted in two steps. The first step was a market survey using a nonprofit application helping consumers avoid problematic substances in cosmetic products. The application contained 10 067 cosmetic products that were label checked for naturally derived cosmetic product ingredients. The second step was a literature search to examine how frequently the naturally derived ingredients were described and related to allergic reactions in cosmetics or other topically administered products.

RESULTS

We identified 121 different naturally derived cosmetic product ingredients that were included in at least 30 cosmetic products. In total, 22 ingredients were selected for a screening test series.

CONCLUSIONS

We propose a supplemental patch test and a prick test screening series with naturally derived cosmetic product ingredients for patients with skin reactions to cosmetic products, aiming to identify a cause in more patients than is currently possible.

Contact Allergy-Emerging Allergens and Public Health Impact

Contact allergy (sensitisation) and allergic contact dermatitis (ACD) resulting from it have a considerable public health impact. For the present review, all pertinent articles were systematically searched via Medline and Web of Science™; additionally, all available issues of the journals "Contact Dermatitis" and "Dermatitis" were manually searched, covering the years 2018-2019, thereby extending and re-focusing a previous similar review. New allergens, or previously described allergens found in a new exposure context or of other current importance, are described in sections according to substance classes, e.g., metals, preservatives, fragrances. As a common finding in many investigations, a lack of information on product composition has been noted, for instance, regarding a newly described allergen in canvas shoes (dimethylthiocarbamylbenzothiazole sulfide) and, most notably, absence of co-operation from manufacturers of glucose-monitoring devices and insulin pumps, respectively. These latter devices have been shown to cause severe ACD in a considerable number of diabetic patients caused by the liberation of isobornyl acrylate and N,N'-dimethylacrylamide, respectively, as demonstrated by an international collaboration between dermatologists and chemists. Improved and complete ingredient labelling for all types of products, and not just cosmetics, must be put on the legislative agenda.

Limonene Hydroperoxides

Limonene is a fragrance widely used in cosmetics and household products. Until recently, contact allergy to limonene was considered rare because positive patch tests to it were infrequently observed. In recent years, however, it has been demonstrated that exposure of limonene to oxygen (air) results in the formation of a number of oxidation products, of which the hydroperoxides have a far stronger sensitizing potency than the pure compound. By routine testing of patients suspected of contact dermatitis with hydroperoxides of limonene, high frequencies of positive reactions were found, indicating that these chemicals are important fragrance allergens. It should be realized, however, that a number of "positive" reactions may well be false-positive, irritant responses.

Linalool Hydroperoxides

Linalool is a fragrance widely used in cosmetics and household products. Until recently, contact allergy to linalool was considered rare because positive patch tests to it were infrequently observed. In recent years, however, it has been demonstrated that exposure of linalool to oxygen (air) results in formation of a number of oxidation products, of which the hydroperoxides have a far stronger sensitizing potency than the pure compound. By routine testing of patients suspected of having contact dermatitis with hydroperoxides of linalool, high frequencies of positive reactions were found, indicating these chemicals are important fragrance allergens. It should be realized, however, that a number of "positive" reactions may well be false-positive, irritant responses.

Cosmetics for neonates and infants: haptens in products' composition

Cosmetics and skin care products for neonates and infants are considered as ‘‘hypoallergenic’’, “tested” or ‘‘safe’’. Nevertheless, the prevalence of haptens in these products is a matter of concern, since allergic contact dermatitis in children is gaining an importance. We aimed to assess the prevalence of haptens in cosmetics designed for children younger than 1 year. To identify haptens, the components of the cosmetics listed on packaging were compared with substances from European baseline series, Cosmetics series and Fragrance series. Survey comprised 212 cosmetics among which 186 (87.7%) contained at least one hapten from reference lists. Altogether there were 41 different haptens found in cosmetics. Number of sensitizers per product ranged between 1–12 and, each product contained 2.51 haptens on average. The most abundant sensitizers were cocamidopropyl betaine, tocopherol, propylene glycol, fragrances, lanolin. Majority of products for children were labeled as hypoallergenic/dermatologically tested/safe for children etc. from which 85% contained haptens. This survey highlights the extent of presence of haptens in cosmetics for children under the first year of age.

Do consumers care about substances of very high concern in articles?

BACKGROUND

Consumers have the right to inquire whether a consumer article contains substances of very high concern ('SVHC right to know'). This communication tool is designed to stimulate suppliers to substitute such ingredients. A survey among 1321 consumers with high motivation and interest in harmful substances in everyday products was conducted to understand the acceptance of this 'right to know' among consumers.

RESULTS

Only one out of seven survey participants stated to be well informed about the 'SVHC right to know' with nearly all of them having good self-reported chemical knowledge. Three quarters of the participants who are not working with chemicals or REACH at their workplace have never heard about the 'SVHC right to know'. Every second participant declared their interest to search for more information about an SVHC in a certain article, but, in fact, not more than 4% of all participants inquired for SVHCs with various methods. Only 1% would buy an SVHC-containing article with no strings attached. While detailed comments by some survey participants showed a high level of understanding of the issue, many respondents were not sure what the SVHC information means for their daily life. They declared that they would inform themselves, reduce the use of the article with SVHCs, circulate this information, or throw such an article into the garbage. Most study participants suggested improvements of the 'SVHC right to know'. The preferred suggestions were a ban of SVHCs, easily understandable information on the packaging, full ingredient declaration on the articles, or no need to inquire for every single item, while smartphone applications for SVHC requests were the least popular suggestion in all age groups.

CONCLUSIONS

Various reasons could be identified why most consumers-even these motivated and interested ones-do not use the 'SVHC right to know'. This allowed developing recommendations for improving the effectiveness of this communication instrument on the way to the gradual elimination of SVHCs in consumer articles.

Contact Allergy: A Review of Current Problems from a Clinical Perspective

Contact allergy is common, affecting 27% of the general population in Europe. Original publications, including case reports, published since 2016 (inclusive) were identified with the aim of collating a full review of current problems in the field. To this end, a literature search employing methods of systematic reviewing was performed in the Medline^® and Web of Science™ databases on 28 January 2018, using the search terms (“contact sensitization” or “contact allergy”). Of 446 non-duplicate publications identified by above search, 147 were excluded based on scrutiny of title, abstract and key words. Of the remaining 299 examined in full text, 291 were deemed appropriate for inclusion, and main findings were summarised in topic sections. In conclusion, diverse sources of exposures to chemicals of widely-differing types and structures, continue to induce sensitisation in man and may result in allergic contact dermatitis. Many of the chemicals are “evergreen” but others are “newcomers”. Vigilance and proper investigation (patch testing) are required to detect and inform of the presence of these haptens to which our populations remain exposed.