Hydroxyisohexyl 3-cyclohexene Carboxaldehyde Research Articles

Contact allergy to hydroxyisohexyl 3-cyclohexene carboxaldehyde in Italy: Prevalence, trend, and concordance with fragrance mix II.

Hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC), contained in fragrance mix II (FM II), has been recognized as a contact sensitizer since the mid-1990s. After several attempts to reduce its use during the last two decades, HICC was permanently banned from the European market in August 2021. To assess the prevalence and the time trend of contact allergy to HICC and to investigate the concordance of HICC allergy compared to FM II allergy in an unselected Italian patch test population. Retrospective analysis on demographics and patch test results of HICC-sensitized and/or FM II-sensitized patients was performed over a 6-year period (2016-2021) at 6 patch test Clinics in Italy. Among 7266 patients (4942 females, 68.0%, mean age 45.4 ± 20.6 years), 1% (70) resulted positive to HICC and 2.1% (153) to FM II. Clinical relevance was documented in 72.9% (51/70) of HICC positive patients. Among the 169 HICC and/or FM II positive patients, 9.5% had a positive reaction to HICC only, 31.9% to both HICC and FM II, and 58.6% to FM II only. The prevalence trend line of HICC positive reactions showed a decrease from 1.15% (2016) to 0.96% (2021). We documented a decreasing trend of HICC allergy in Italy, in line with the data recently reported in literature. Nevertheless, HICC should be maintained in the baseline series to monitor the benefits of its ban from the European market.

Low Prevalence of Fragrance Contact Allergy Among Turkish Population: A 24-Year, Cross-Sectional, Tertiary Single-Center, Retrospective Study.

Limited data exist on fragrance contact allergy among Turkish population. The aim of this study was to investigate the frequency and characteristics of fragrance contact allergy in Turkey. A retrospective cohort study was conducted on 2566 patients consecutively patch tested with the European baseline series and additionally with a fragrance series (n = 358) at a tertiary referral center between 1996 and 2019. One hundred sixty-three patients (6.4%) (male/female, 1.5:1) were sensitized with at least 1 fragrance allergen. Fragrance mix (FM) I was most frequently positive (3.9%), followed by Myroxylon pereirae (3.1%), FM II (2%), and hydroxyisohexyl 3-cyclohexene carboxaldehyde (0.5%), the latter exclusively positive in FM II-positive patients. Among 358 patients patch tested with a fragrance series, positive patch test reactions were observed in 38 patients, including 8 who did not react to baseline fragrance markers. Clinically relevant fragrance allergy was established in 128 patients (78.5%) from nonoccupational (72.4%) and occupational (6.1%) sources. The low prevalence, the middle-aged male preponderance, and the predominant involvement of hands were unusual findings. Rose/citrus-flavored perfumes and eau de cologne, which are traditionally preferred in our country, were important elicitors of fragrance contact allergy, especially among middle-aged and older men.

Allergic contact dermatitis in healthcare workers.

Allergic contact dermatitis is a common occupational skin disease among healthcare workers (HCWs). This study describes causes of allergic contact dermatitis in New Zealand HCWs. All HCWs undergoing patch testing between July 2008 and January 2020 at a public hospital patch test clinic and between June 2019 and January 2020 at a private dermatology clinic were included. Data collected included patient demographics, occupation, results of patch testing and pre- and post-patch test diagnoses. Out of 837 patients tested, 67 were HCWs. The mean age of HCWs was 41 years (SD 14) and 58 (87%) were female. The most common occupations were nurses (40%), allied health (22%) and doctors (18%). Forty-six (69%) patients had a background of atopic dermatitis. Hand dermatitis was the most common presentation (49%), followed by facial/neck dermatitis (25%). Thirty-eight (57%) had at least one positive reaction on patch testing, including 19 (28%) with a positive result of current relevance. There were 16 relevant reactions to rubber accelerators, 11 to fragrances, 10 to preservatives and 6 to corticosteroids. The most frequent relevant allergens were methylisothiazolinone/methylchloroisothiazolinone (4%), hydroxyisohexyl 3-cyclohexene carboxaldehyde (4%) and methylisothiazolinone (4%). The most common allergens in HCWs were rubber chemicals, fragrances, preservatives and topical corticosteroids. Important allergens for patch testing HCWs are outlined, in particular, those with hand dermatitis should be tested to a rubber series.

Associated positive patch test reactions to standard contact allergens: 10-year data from the Slovenian E-Surveillance System.

A considerable share of patients tested with a baseline patch test series respond with a positive reaction to more than one allergen, and some associations between synchronous positive reactions to distinct baseline patch allergens have been described in the literature. To evaluate the prevalence of sensitization to haptens of the European baseline series as well as the prevalence of oligosensitization and polysensitization and the most significant associated positive patch test reactions in Slovenia. Patch testing data collected by the Slovenian E-Surveillance System from January 2008 to December 2017 were retrospectively analysed. Of a total of 15 171 patients analysed, 39.29% showed at least one positive reaction. The highest prevalences were noted for metals (nickel[II]sulfate hexahydrate: 16.33%) and fragrances (fragrance mix I: 6.70%). The correlation analysis showed the strongest correlation between mercapto mix and 2-mercaptobenzothiazole (61.2%), fragrance Mix II and hydroxyisohexyl 3-cyclohexene carboxaldehyde (50.5%), and potassium dichromate and cobalt(II) chloride hexahydrate (33.3%). Sensitization prevalences to the most common haptens were described, and their strongest correlations on a national level quantified. A comparison with other European results confirms already known associations between allergens in terms of cross-reactivity.

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

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

Decrease of contact allergy to hydroxyisohexyl 3‐cyclohexene carboxaldehyde in Europe prior to its ban and diagnostic value

Hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) has been the most reported fragrance chemical for two decades and will be prohibited in cosmetic products from August 2021. To describe the time trend of HICC contact allergy in European patients with dermatitis in 2009 to 2019, and the added value of testing HICC separately in the baseline series. Data were reviewed for 124 472 patients with dermatitis who were patch tested with HICC 5% pet. in the baseline series in the European Surveillance System on Contact Allergy (ESSCA) network (2009 to 2018) and at the Herlev-Gentofte Hospital Department of Dermatology and Allergy (2009 to 2019). Contact allergy to HICC was found in 1.98% of 9865 patients in Gentofte and 1.62% of 114 607 patients in the ESSCA network. Overall, the prevalence decreased annually, with 0.156 percentage points (P = .001) in Gentofte and 0.051 percentage points (P = .0002) in ESSCA. The frequency of missed contact allergy to HICC when testing only with fragrance mix II (FMII) was 0.17% (17/9865) and 0.35% (405/114607) of the whole test population in the Gentofte and ESSCA populations, respectively. This is the first study to demonstrate a significant decline in HICC allergy in European patients with dermatitis, most likely attributed to the upcoming European ban.

Prevalence, concomitant reactions, and factors associated with fragrance allergy in Thailand.

Fragrances are the most common cause of cosmetic contact allergy. Up-to-date information on contact allergy frequencies and relevance aids primary and secondary preventive measures. To determine the prevalence, associated factors, and concomitant reactions in fragrance allergy among Thais. This retrospective study collected data from 2012 to 2019. The patient characteristics of fragrance and nonfragrance allergy groups were compared. Concurrent positive reactions to fragrance allergens (fragrance mix [FM] I, FM II, Myroxylon pereirae resin and hydroxyisohexyl 3-cyclohexene carboxaldehyde) and other baseline-series allergens were analysed. Of 1032 patients, 175 (17.0%) had fragrance allergy, with 57.7% of clinical relevance. FM I showed the highest prevalence (9.4%). The associated factors were being elderly, lesions on the extremities, metal allergy history, and long dermatitis duration. Contact allergies to epoxy resin and Compositae plants were significantly associated with fragrance allergy with an odds ratio of 5.95 (95% confidence interval [CI]: 5.21-6.80) and an odds ratio of 4.42 (95% CI: 1.58-12.36), respectively. No significant associations between colophonium (previously proposed as a fragrance marker) and fragrance allergens were found. The prevalence of fragrance contact allergy remains high and should be considered in old patients presenting with long-standing eczema on the extremities. Unlike reports from other countries, varied, significant, concomitant reactions were observed.

Review on perfume and present status of its associated allergens.

Perfume is basically a cosmetic product applied to human body for an amusing scent or the feeling of freshness. A certain amount of perfume penetrates and remains attached to the protein of the skin when perfume is applied on the body. It evokes a surge of events in human immune system which results with allergic symptoms. Fragrance ingredients are leading cause that can be responsible for the occurrence of allergic contact dermatitis that is recently studied under cosmetic adverse reaction. The aim of this review article was to define the allergies that are caused by fragrance ingredients. This review highlights the various aspects of perfume with respect to its manufacturing process, compositions, and fragrance ingredients identified as allergens and its present regulatory status. There area 175 frangrance ingredients that are used in perfumes cause allergic reaction. Several studies were conducted on the patients. The study was conducted on four fragrance markers in the baseline series: fragrance mix I (FM I), Myroxylon pereirae, fragrance mix II (FM II), and hydroxyisohexyl 3-cyclohexene carboxaldehyde. Around 658 patients showed allergy due to fragrance ingredients when the patch test was performed. In other study, out of 1253 patients, 90% of the FM I and M. pereirae detected 90% of the cases. Majority of the fragrance ingredients can cause allergic reactions and hence act as allergens and thus increase the risk of sensitization on activation. If any individual suffers from allergy or contact dermatitis on use of any perfume, he/she should be aware of it and should reduce or avoid its use to overcome such problems of hypersensitivity.

Contact Allergy to Fragrance Mix II and Hydroxyisohexyl 3-Cyclohexene Carboxaldehyde: A Retrospective Study by International Contact Dermatitis Research Group.

Fragrance mix II (FM II) is included in the baseline patch test series recommended by the International Contact Dermatitis Research Group (ICDRG). Hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) is the most important sensitizer of the 6 fragrance materials included in FM II. Besides being a part of FM II, HICC is also tested separately in the ICDRG baseline series. The aim of the study was to investigate the prevalence of contact allergy to FM II and HICC in 2012-2016 with a focus on simultaneous reactions and the percentage of missed contact allergy to HICC provided that only FM II had been tested. A total of 25,019 consecutive dermatitis patients in 13 dermatology clinics representing 12 countries in 5 continents were patch tested with FM II and HICC in the baseline series. Contact allergy to FM II and HICC was found in 3.9% and 1.6%, respectively. For FM II, the frequency varied from 1.5% to 7.6% in different centers. The corresponding range for HICC was 0.2% to 3.6%. Simultaneous contact allergy to FM II and HICC was noted in 1.4% with the range 0.2% to 2.6%. Seventy-seven patients (0.31%) with contact allergy to HICC did not test positively to FM II. The range for missed HICC allergy by testing only FM II in the different centers would be 0.04% to 0.74%. The ratio between the contact allergy rates for FM II and HICC was similar for all centers, except for Montreal having significantly more contact allergy to FM II than to HICC. The frequency of missed contact allergy to HICC when testing only with FM II was less than 0.5%, therefore questioning the need to test HICC separately in the ICDRG baseline series.

Trends and current spectrum of contact allergy in Central Europe: results of the Information Network of Departments of Dermatology (IVDK) 2007-2018.

Changing patterns of exposure lead to changes in the spectrum of contact allergy in the general population and in patients patch tested for suspected contact allergy. The main contact allergens (haptens) are assembled in the so-called 'baseline series'. To present the current spectrum of contact allergy to baseline series allergens, and its temporal development over the last 12 years, based on data collected by the 56 active departments of the trinational Information Network of Departments of Dermatology (IVDK). Patch-test data, along with core demographic and clinical information, subdivided into 4-year periods for all patients patch tested with the baseline series in the IVDK, were analysed descriptively. Moreover, log-binomial regression analysis addressed temporal trends of specific contact allergies, adjusted for potentially confounding factors. Among the 125436 patients tested with the German baseline series, the most common allergens were nickel (14·7%), fragrance mix I (8·1%), Myroxylon pereirae resin (7·5%) and cobalt (5·2%), with no conclusive trend. The rise and fall of contact allergy to methylchloroisothiazolinone/methylisothiazolinone (MI), following (self-) regulation in the European Union, reflected the MI contact allergy epidemic. Propolis showed a marked upward trend with a prevalence of 3·94% during the period 2015-2018. Decreases in sensitization prevalence likely reflect reduced exposure, with some lag, as seen with hydroxyisohexyl 3-cyclohexene carboxaldehyde. If no (sufficient) decrease can be observed despite interventions, such as for nickel and chromium, affected subgroups should be identified and their causative exposures explored. Finally, increases such as that observed with propolis, certainly warrant targeted investigation of the exposures driving sensitization, and possibly intervention. What is already known about this topic? Contact allergy is prevalent in the general population. Surveillance based on clinical data offers timely information on trends concerning certain allergens or subgroups at risk. What does this study add? This analysis provides an update of the current contact allergy prevalence in Central Europe, including time trends. This study describes the demographic and clinical profile of patients tested from 2007 to 2018. This research identifies contact allergens that require (further) preventive efforts. Linked Comment: Schuttelaar. Br J Dermatol 2020; 183:800-801.

How common is fragrance allergy really?

Fragrances are regarded as the most common contact allergens after nickel. In this context, the frequency of positive patch test reactions to fragrance mix is often presented as proof. According to EU regulation No.1223/2009, 26fragrances that are regarded as significant allergens have to be declared on cosmetic products. The frequency of patch test reactions to fragrances and differentiation between frequently and rarely sensitizing fragrances were evaluated. Data from the Information Network of Departments of Dermatology (IVDK), mostly of the years 2016-2018, were retrospectively analyzed. Frequency of positive reactions to fragrance mixI in the departments of dermatology joining the IVDK reached ahistorical low of 5.4% in 2018. Since 2013, positive reactions to fragrance mixII have been declining, yielding 3.2% in 2018. Of fragrance mixI, the allergen with the most positive test reactions is no longer oakmoss absolute, but isoeugenol. In fragrance mixII, hydroxyisohexyl 3‑cyclohexene carboxaldehyde (HICC) is still leading. Only 11of the 26fragrances subject to mandatory declaration elicited allergic test reactions in more than 1% of the patients tested. The decline of positive test reactions to the fragrance mixes is mainly due to the reduced use of oakmoss containing atranol and chloroatranol, and HICC. Use of these substances in cosmetic products was prohibited within the EU starting in August 2019. Therefore, afurther decline of the sensitization frequencies can be expected. Adifferentiated consideration of the individual fragrances under allergological aspects is urgently required.

Fragrances: Contact Allergy and Other Adverse Effects.

This article gives an overview of fragrance allergy. The following subjects are discussed: composition of perfumes, contact with fragrances, diagnosing fragrance allergy, frequency of allergy, clinical picture of allergic contact dermatitis, culprit products, occupational contact dermatitis, and other adverse effects of fragrances. For diagnosing fragrance sensitization, personal products and a fragrance series may need to be tested in addition to the baseline series. In the general adult population, up to 4.5% may be allergic to fragrance materials, and in consecutive patients patch tested for suspected contact dermatitis, the frequency may reach 20% to 25%. More than 150 fragrances have caused contact allergy. The most frequent sensitizers are linalool and limonene hydroperoxides, hydroxyisohexyl 3-cyclohexene carboxaldehyde, treemoss and oakmoss absolute, isoeugenol, cinnamyl alcohol, and cinnamal. Culprit products for induction of sensitization are often deodorants, fine fragrances, and aftershaves. Occupational contact dermatitis from fragrances is seen occasionally. Other adverse effects are all discussed but occur infrequently.

Sensitization to fragrances in Spain: A 5‐year multicentre study (2011‐2015)

Fragrance chemicals constitute the second most frequent cause of contact allergy in Spain. There are no data available concerning the individual fragrances that are most frequently involved. To describe the diagnostic contribution provided by specific fragrance series to the results obtained with baseline series fragrance markers by correlating the results of both series. We performed a 5-year retrospective study of fragrance marker-positive patients tested with specific fragrance series in 23 Spanish centres. We collected the demographic and clinical characteristics, and compared the results of patch tests obtained from different suppliers. Of 19 588 patients patch tested with the Spanish baseline series, 1590 (8.1%) reacted positively to a fragrance marker. Of these, 1013 (63.7%) were patch tested with a fragrance series, and 664 patients reacted positively to at least one individual fragrance other than hydroxyisohexyl 3-cyclohexene carboxaldehyde. Geraniol was the most frequent allergen. Positive reactions to substances not included in fragrance mix (FM) I or FM II were found in 230 patients. Of the 436 FM I-positive patients and the 419 FM II-positive patients, 184 (42%) and 64 (39.1%), respectively, had no positive reactions to fragrance series. In the case of FM I, negative results were more common when individual fragrances were patch tested at low concentrations. We recommend patch testing all patients positive for any fragrance marker with a specific fragrance series. The correlation between the results of baseline series and fragrance series could be improved by increasing the concentrations of individual fragrances.

Fragrances as allergens

Contact allergies due to fragrances are common. If one adds up the reaction incidences of the indicators of fragrance allergy (fragrance mix [FM] I + II, balsam of Peru and turpentine), these reach 17% in a hospital collective (Information Network of Departments of Dermatology [IVDK] data 2016) and are thus higher than those for nickel allergy (approximately 16%). In the case of positive reactions to FM I, >50% do not react to one of the components. This type of reaction should be interpreted as allergic with caution, unless other data (e. g., positive history, application test) support this interpretation. FM-I-positive individuals often react to oak moss (27.2%) and isoeugenol (18.2%). These are followed by hydroxycitronellal (10.9%), cinnamal (10.6%), cinnamyl alcohol (8.4%), eugenol (7.3%), geraniol (5.5%), and amyl cinnamal (1.5%). The frequency of sensitization (SF) to the individual fragrances depends on their allergenic potency (measured using the local lymph node assay, LLNA) and the frequency of use (extent of exposure). The relationship between SF and exposure is described by the sensitization exposure quotient (SEQ). The SEQ is a measure of the risk of sensitization. In general, it correlates with the SF on the one hand and with the allergenic potency (hazard) on the other. Exceptions to this rule indicate a newly recognized problem: (1) Although methyl 2-octynoate plays no role in SH statistics, it came third after tree moss and oak moss with its SEQ (=risk); (2) despite its low potency, hydroxyisohexyl 3-cyclohexene carboxaldehyde (Lyral®) had a relatively high risk. In this particular case, potency (the inherent hazard) was not the determinant of risk, but rather the overly high doses used. Allergy monitoring by clinical epidemiology needs to be more heavily supplemented by data on exposure.

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

More than 25% of the adult European population suffers from contact allergy, with fragrance substances recognized as one of the main causes. Since 2005, 26 fragrance contact allergens have been mandatory to label in cosmetic products within the EU if present at 10ppm or above in leave-on and 100ppm or above in wash-off cosmetics. To examine exposure, based on ingredient labelling, to the 26 fragrances in a sample of 5588 fragranced cosmetic products. The investigated products were identified through a novel, non-profit smartphone application (app), designed to provide information to consumers about chemical substances in cosmetic products. Products registered through the app between December 2015 and October 2016 were label checked according to International Nomenclature of Cosmetic Ingredients (INCI) for the presence of the 26 fragrance substances or the wording 'fragrance/parfum/aroma'. The largest product categories investigated were 'cream, lotion and oil' (n=1192), 'shampoo and conditioner' (n=968) and 'deodorants' (n=632). Among cosmetic products labelled to contain at least one of the 26 fragrances, 85.5% and 73.9% contained at least two and at least three of the 26 fragrances, respectively. Linalool (49.5%) and limonene (48.5%) were labelled most often among all investigated products. Hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC/Lyral® ) was found in 13.5% of deodorants. Six of the 26 fragrance substances were labelled on less than one per cent of all products, including the natural extracts Evernia furfuracea (tree moss) and Evernia prunastri (oak moss). A total of 329 (5.9%) products had one or more of the 26 fragrance substances labelled but did not have 'parfum/fragrance/aroma' listed on the label. Consumers are widely exposed to, often multiple, well-established fragrance contact allergens through various cosmetic products intended for daily use. Several fragrance substances that are common causes of contact allergy were rarely labelled in this large sample of cosmetic products.

Simultaneous patch testing with fragrance mix I, fragrance mix II and their ingredients in southern Sweden between 2009 and 2015.

Fragrance mix I (FM I) and fragrance mix II (FM II) are included in the European baseline series as screening substances for fragrance contact allergy. To investigate the frequency of allergic reactions to FM I, FM II and their ingredients in consecutively patch tested patients. A retrospective analysis of data from 4430 patients patch tested between 2009 and 2015 was performed. Of the patients, 6.5% were FM I-positive and 3.2% were FM II-positive. Forty-five per cent of FM I-positive patients did not have positive reactions to FM I ingredients. Thirty-five per cent of those who were FM II-positive did not have positive reactions to FM II ingredients. Twenty-seven per cent of those with positive reactions to one or more of the FM I ingredients were FM I-negative, and 36% of those who had positive reactions to one or more of the FM II ingredients were FM II-negative. The allergens with the highest pick-up rates were Evernia prunastri (1.8%), cinnamal (1.3%), citral (1.2%), and hydroxyisohexyl 3-cyclohexene carboxaldehyde (1.2%). Significant differences were observed in the proportions of positive reactions to FM I, FM II, eugenol, isoeugenol, and farnesol when results from patch testing with materials from different suppliers were compared. There is a risk of missing fragrance contact allergy when testing with only the fragrance mixes is performed. The use of preparations from different suppliers may affect the patch test results.

Contact allergy to fragrances: current clinical and regulatory trends.

. Several fragrances are important contact allergens. Compared to the immense multitude of more than 2,500 fragrances used in cosmetics, the spectrum of single substances and natural extracts used for patch testing appears limited, albeit comprising the supposedly most important contact allergens. The present review summarizes the most important results of the opinion of the Scientific Committee on Consumer Safety on fragrance allergens in cosmetic products from July 2012. Clinical results beyond abovementioned screening allergens, animal results in terms of the LLNA and structure activity considerations point to 100 single substances and extracts, respectively, which, in addition to those 26 already identified, must be considered contact allergens, and the presence of which should be declared in cosmetics. In case of the most commonly used fragrance terpenes limonene and linalool hydroperoxides resulting from autoxidation constitute the major allergens. These have become available as patch test material recently. Altogether 12 single substances have caused a (very) high number of published cases of sensitization. Thus their use concentration should be (further) reduced or, in case of hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC, e.g., Lyral®), use should be abandoned altogether. This is also recommended in case of oak moss and tree moss due to their content of the strong sensitizers atranol and chloroatranol. As generic maximum dose for the remaining 11 single substances 0.8 µg/cm2 are suggested, which corresponds, under conservative assumptions, a maximum concentration of 100 ppm in the finished product.

Non-mix fragrances are top sensitizers in consecutive dermatitis patients - a cross-sectional study of the 26 EU-labelled fragrance allergens.

For cosmetics, it is mandatory to label 26 fragrance substances, including all constituents of fragrance mix I (FM I) and fragrance mix II (FM II). Earlier reports have not included oxidized R-limonene [hydroperoxides of R-limonene (Lim-OOH)] and oxidized linalool [hydroperoxides of linalool (Lin-OOH)], and breakdown testing of FM I and FM II has mainly been performed in selected, mix-positive patients. To report the prevalence of sensitization to the 26 fragrances, and to assess concomitant reactivity to FM I and/or FM II. A cross-sectional study on consecutive dermatitis patients patch tested with the 26 fragrances and the European baseline series from 2010 to 2015 at a single university clinic was performed. Of 6004 patients, 940 (15.7%, 95%CI: 14.7-16.6%) were fragrance-sensitized. Regarding the single fragrances, most patients were sensitized to Lin-OOH (3.9%), Evernia furfuracea (3.0%), Lim-OOH (2.5%), and hydroxyisohexyl 3-cyclohexene carboxaldehyde (2.1%). Significantly fewer patients were 'FM I-positive and constituent-positive' than 'FM II-positive and constituent-positive' (32.7% versus 57.0%, p < 0.0001). Additionally, significantly more patients were 'FM II-negative but constituent-positive' than 'FM I-negative but constituent-positive' (12.4% versus 3.2%, p = 0.0008). Non-mix fragrances are the most important single fragrance allergens among consecutive patients. The test concentration of the single FM I constituents should be increased when possible.

Patch testing with hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC)-a multicentre study of the Swedish Contact Dermatitis Research Group.

In 2014, the fragrance hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) was excluded from the Swedish baseline series. To study (i) whether fragrance mix (FM) II with 5% HICC detects more positive reactions than usual FM II with 2.5% HICC, and (ii) the reproducibility of patch testing with HICC. Two thousand one hundred and eighteen dermatitis patients at five Swedish dermatology departments were consecutively tested with FM II 14% pet., FM II 16.5% pet., and duplicate preparations of HICC 5% pet. Of the patients, 3.2% reacted to FM II 14%, and 1.5% reacted to HICC. Separate testing with HICC detected 0.3% reactions without concomitant reactivity to FM II. FM II with 5% HICC did not give rise to more irritant reactions or signs of active sensitization than FM II with 2.5% HICC. Patch testing with duplicate applications of HICC increased the overall prevalence of HICC contact allergy to 1.9%. FM II with 5% HICC does not detect more positive reactions than FM II with 2.5% HICC. Separate testing with HICC does not detect a sufficient proportion of patients who react only to HICC, without concomitant reactions to FM II, to warrant its inclusion in a baseline series.

Occupational contact sensitization in female geriatric nurses: Data of the Information Network of Departments of Dermatology (IVDK) 2005-2014.

Geriatric nurses (GN) have a high risk of occupational contact dermatitis (OCD), with chronic irritant contact dermatitis predominating. However, allergic contact dermatitis is an important issue as well. Little is known whether the relevant occupational allergen spectrum reported in the 1990s, including fragrances, preservatives, rubber chemicals and ingredients of surface disinfectants to be the most common sensitizers in GN, is still valid. To monitor the current allergen spectrum in GN with OCD and verify the validity of the patch test recommendations (baseline-, preservative-, ointment base-, rubber-, disinfectant, series and fragrances) in GN with suspected OCD given by the German Contact Dermatitis Research Group (DKG). Retrospective analysis of IVDK data (2005-2014) of 743 female GN with OCD, in comparison to 695 GN without OCD. GN with OCD reacted significantly more frequently to both fragrance mixes, hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC), thiuram mix, zinc diethyldithiocarbamate and mercaptobenzothiazole than GN without OCD. Reactions to MDBGN, methylchloroisothiazolinone/methylisothiazolinone and oil of turpentine occurred substantially, but not significantly more frequently among GN with OCD. The latter may be due to former use of a special alcoholic liniment in geriatric care. Among material from the patients' workplaces, tetrazepam was a frequent allergen, due to dust exposure from pill crushing. Furthermore, occupationally used protective gloves, body care products as well as surface disinfectants were often tested positively. The general allergen spectrum in GN with OCD is unchanged, so the DKG patch test recommendations are still valid. Prevention of occupational sensitization should focus on fragrance-free hygiene and body care products, usage of accelerator-free protective gloves and avoidance of drug dust exposure.