Non-occupational Allergic Contact Dermatitis Research Articles

Nonoccupational Allergic Contact Dermatitis to 4-Acryloylmorpholine in Smartwatch Screen Protectors Glue.

We recently identified an outbreak of occupational allergic contact dermatitis (ACD) involving workers of a Spanish company selling smartphone protective cases from a glue product. A chemical analysis of one glue sample revealed the presence of 4-acryloylmorpholine among other allergens.The same glue is also used to attach tempered glass protective cases to Apple smartwatches. Our objective was to describe a case series of nonoccupational consumer ACD from the previously mentioned Apple smartwatch protective case glue. We evaluated epidemiological and clinical data, as well as patch tests results. Three women were diagnosed with nonoccupational ACD from the adhesive. An annular vesicular inflammatory plaque involving the dorsal aspect of the wrist was initially observed in all. Two of the 3 patients were patch tested with 4-acryloylmorpholine 0.5% with positive strong reactions. Both also strongly reacted to a sample of the glue semiopen tested in a drop of petrolatum. One of them was also positive for various acrylates. 4-Acryloylmorpholine has been identified in an adhesive used to attach protective cases to smartwatches. Nonoccupational ACD have been described to involve consumers of smartwatches. A UV-curable adhesive used to attach protective cases to smartwatches has been considered to be the culprit.

North American Contact Dermatitis Group Patch Test Results: 2017-2018.

Patch testing is an important diagnostic tool for assessment of allergic contact dermatitis (ACD). This study documented the North American Contact Dermatitis Group (NACDG) patch testing results from March 1, 2017, to December 31, 2018. At 14 centers in North America, patients with dermatitis were tested in a standardized manner with a screening series of 70 allergens and supplemental allergens as clinically indicated. Data were manually verified and entered into a central database. Descriptive statistics were estimated, and trends were analyzed using χ2 test. Overall, 4947 patients were tested. There were 3235 patients (65.4%) who had at least 1 positive reaction and 2495 patients (50.4%) had a primary diagnosis of ACD. Five hundred eighty-one patients (11.7%) had occupationally related dermatitis. There were 10,122 positive patch test reactions. Nickel remained the most commonly detected allergen (16.2%), followed by methylisothiazolinone 0.2% aqueous (15.3%) and methylchloroisothiazolinone/methylisothiazolinone 0.02% aqueous (200 ppm, 11.0%). Compared with the previous reporting periods (2015-2016 and 2007-2016), the proportion of positive reactions for the top 20 screening allergens statistically increased for only 1 allergen, propolis (3.4%; risk ratios = 2.05 [confidence interval = 1.66-2.54] and 1.82 [confidence interval = 1.57-2.11]).Four newly added allergen preparations, hydroperoxides of linalool (8.9%), benzisothiazolinone (7.3%), sodium metabisulfite (2.7%), and hydroperoxides of limonene (2.6%), all had a prevalence of greater than 2%. Approximately 1 (19.7%) in 5 tested patients had 1 or more clinically relevant reactions to an allergen not on the NACDG screening series; 13.2% of these were occupationally related. T.R.U.E. TEST (SmartPractice Denmark, Hillerød, Denmark) would have hypothetically missed 30% to 40% of reactions detected by the NACDG screening series. These results demonstrate the importance of a regularly updated screening allergen series. Methylisothiazolinone continues to be a significant allergen in North America. Patch testing with allergens beyond a screening tray is necessary for complete evaluation of occupational and non-occupational ACD.

Acrylates as a significant cause of allergic contact dermatitis: new sources of exposure.

Acrylate monomers have a wide range of applications. Since the 1950s, many reports of occupational origin allergic contact dermatitis due to (meth)acrylate monomers have been published. During last decades, (meth)acrylate allergy has undergone an occupational shift from dentistry toward beauty industry and medical devices. The aim of the study was to conduct a literature review on acrylates as a cause of allergic contact dermatitis, current sources of exposure as well as identification of professional groups with an increased risk of this allergy and methods of effective prevention. Database review: Medline search (PubMed), Wiley Online Library and Web of Science base in years 1956–2019 using the following keywords: acrylates, manicurists, dentists, dental technicians, medical devices, occupational exposure, and allergic contact dermatitis. 204 346 articles containing the term ‘acrylates‘ have been found. They include 2 042 articles with the word ‘manicurists’, 169 919 – ‘dentists’, 218 236 – ‘dental technicians’, 2 427 418 – ‘medical devices’. Fifty-nine articles were chosen based on analysis of abstracts and full texts. In the past allergy to acrylates was mainly of occupational origin and dental technicians were the most often affected professional group. Since the long-lasting manicure has become popular, this problem concerns both manicurists and their customers. Moreover, the new significant trend is non-occupational allergic contact dermatitis caused by medical devices especially dedicated to diabetes patients.

Methylchloroisothiazolinone/methylisothiazolinone and methylisothiazolinone contact allergy: A 24-year, single-center, retrospective cohort study from Turkey.

Methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) and MI allergy caused a global epidemic during the period 2010 to 2015, reaching its peak in 2013/14. To investigate the characteristics of MCI/MI and MI allergy in Turkey over 24 years. A total of 2310 patients patch tested between 1996 and 2019 with MCI/MI 0.01% aq. or MCI/MI 0.02% aq., with or without MI 0.2% aq., were analyzed. The overall prevalence of contact sensitization was 3.3% (n = 77) with a peak level of 16.4% in 2015. The prevalence gradually decreased thereafter, but was still high (6.5%) in 2019. Seventy-three patients had clinically relevant sensitizations. MI could detect clinically relevant sensitizations in all seven patients with a negative patch test reaction to MCI/MI 0.02%. Non-occupational allergic contact dermatitis (ACD) was most frequently seen, mainly in women, with hand/face eczema from rinse-off or leave-on cosmetics, such as wet wipes. Occupational ACD was mainly seen among men with airborne eczema from wall paints in house painters, or with hand eczema from hair gel/wax in men's barbers. The prevalence of MCI/MI and MI sensitization in Turkey following the peak in 2015 is still high. This is probably due to the currently allowed level of 100 ppm for MI in rinse-off cosmetics. This needs to be urgently reduced.

Occupational and non-occupational allergic contact dermatitis to hair dyes in Greece. A 10-year retrospective study.

Oxidative hair dyes are an important source of chemical exposure and a major risk factor for the development of occupational and non-occupational allergic contact dermatitis (ACD) worldwide. To identify the frequency of common allergens associated with occupational and non-occupational ACD to hair dyes during the last 10 years, in Greece. We retrospectively reviewed the medical records of patients with suspected ACD to hair dyes from 2010-2019. All patients with patch-test-confirmed ACD to hair dyes were evaluated. Out of 501 patients with suspected ACD to hair dyes, 362 had at least one positive reaction to hair dye allergens (62.4% were customers and 37.6% were hairdressers). The mean age of customers and hairdressers was 43.8 years and 30.8 years, respectively. Of the customers, 58.9% were exposed to dyes for >10 years and 61% of hairdressers for <5 years. The most common site of ACD among customers was the scalp (85%) and among hairdressers the hands (90%). p-Phenylenediamine (PPD) was the most common contact allergen (52.2%), followed by toluene-2,5-diamine, p-aminophenol, m-aminophenol, and ammonium persulfate. Sensitization prevalences for PPD and cross-reacting allergens have increased in Greece during the last decade, regardless of occupational or non-occupational exposure to hair dyes.

Acrylates: new sources and new allergens.

Acrylates are synthetic thermoplastic resins used in a multitude of products, ranging from bone cement to artificial nails. They represent an important and increasing cause of both occupational and nonoccupational allergic contact dermatitis. Isobornyl acrylate, an acrylic monomer found within ultraviolet-cured inks, adhesives and various medical devices for diabetes, has emerged as an important sensitizer. In addition, long-lasting nail products have played a significant role in the increased prevalence of acrylate allergy. Sensitized individuals classically present with facial or eyelid dermatitis, and some patients experience associated fingertip and nail changes. This manuscript reviews these two important sources of acrylate allergy and summarizes other potential new exposures, including surgical glues and wound-care products.

Non-occupational allergic contact dermatitis to methacrylates – updates

Non-occupational allergic contact dermatitis to methacrylates – updates

North American Contact Dermatitis Group Patch Test Results: 2015-2016.

Patch testing is an important diagnostic tool for the assessment of allergic contact dermatitis (ACD). This study documents the North American Contact Dermatitis Group (NACDG) patch testing results from January 1, 2015, to February 28, 2017. At 13 centers in North America, patients were tested in a standardized manner with a screening series of 70 allergens. Data were manually verified and entered into a central database. Descriptive frequencies were calculated, and trends were analyzed using χ test. A total of 5597 patients were tested. There were 3725 patients (66.6%) who had at least 1 positive reaction, and 2798 patients (50.2%) were ultimately determined to have a primary diagnosis of ACD. A total of 572 patients (10.2%) had occupationally related skin disease. There were 10,983 positive allergic reactions. Nickel remained the most commonly detected allergen (17.5%). Methylisothiazolinone, which was added to the screening series for the 2013-2014 cycle, had the second highest positive reaction rate of allergens tested (13.4%). Compared with the previous reporting periods (2013-2014) and (2005-2014), positive reaction rates for the top 35 screening allergens statistically increased for only 1 allergen: hydroxyethyl methacrylate (3.4%; risk ratios, 1.24 [confidence interval, 1.00-1.54] and 1.46 [confidence interval, 1.23-1.73]). Three newly added allergen preparations-ammonium persulfate (1.7%), chlorhexidine (0.8%), and hydroquinone (0.3%)-all had a reaction rate of less than 2%. Twenty-three percent of the tested patients had at least 1 relevant allergic reaction to an allergen not on the NACDG series; 12% of these were occupationally related. T.R.U.E. Test (SmartPractice Denmark, Hillerød, Denmark) would have hypothetically missed one quarter to almost 40% of reactions detected by the NACDG screening series. These results confirm that the epidemic of sensitivity to methylisothiazolinone has continued in North America. Patch testing with allergens beyond a screening tray is necessary for a complete evaluation of occupational and nonoccupational ACD.

Allergic contact dermatitis caused by acrylates in nail cosmetic products: Case reports and review of the literatures

Abstract Acrylates are esters of acrylic acid, which are potent sensitizers that can cause occupational allergic contact dermatitis (ACD) in dental personnel. More recently, an increasing number of cases of both occupational and non-occupational ACD in beauty industry are observed. Here we present three cases of ACD to acrylate and its derivatives in both nail beauticians and do-it-yourself gel nail users due to exposure to nail cosmetics presenting with chronic hand eczema with severe pulpitis and even nail dystrophy with patch-test-confirmed diagnosis. Chemical analysis of commercial nail cosmetic products has been done in one of the patients and successfully identified 2-hydroxypropyl acrylate as the contact allergen.

North American Contact Dermatitis Group Patch Test Results 2013-2014.

Patch testing is the most important diagnostic tool for the assessment of allergic contact dermatitis. This study documents the North American Contact Dermatitis Group (NACDG) patch testing results from January 1, 2013, to December 31, 2014. At 13 centers in North America, patients were tested in a standardized manner with a screening series of 70 allergens. Data were manually verified and entered into a central database. Descriptive frequencies were calculated, and trends were analyzed using χ test. A total of 4871 patients were tested. There were 3255 patients (66.8%) who had at least 1 positive reaction and 2412 patients (49.5%) who were ultimately determined to have a primary diagnosis of allergic contact dermatitis. A total of 434 patients (8.9%) had occupationally related skin disease. There were 9726 positive allergic reactions. Compared with the previous reporting periods (2011-2012 and 2001-2012, including at least three 2-year cycles), positive reaction rates for the top 25 screening allergens statistically increased for 2 allergens: methylchloroisothiazolinone/methylisothiazolinone (6.4%; risk ratios, 1.26 [1.07-1.50] and 2.08 [1.84-2.37]) and hydroxyethyl methacrylate (2.6%; risk ratios, 1.34 [1.02-1.76] and 1.23 [1.00-1.51]). Methylisothiazolinone, which was added to the screening series for this 2013-2014 cycle, had the third highest positive reaction rate of allergens tested (10.9%). Four other newly added allergen preparations-formaldehyde 2% (7%), diphenylguanidine (3.8%), propylene glycol 100% (2.8%), and benzophenone-4 (2.1%)-all had reaction rates greater than 2%. Twenty-one percent of tested patients had at least 1 relevant allergic reaction to an allergen not on the NACDG series; 14.6% of these were occupationally related. The T.R.U.E. TEST (SmartPractice Denmark, Hillerød, Denmark) would have hypothetically missed one quarter to one third of reactions detected by the NACDG screening series. These results confirm that the epidemic of sensitivity to methylisothiazolinone previously documented in Europe is also occurring in North America. Patch testing with allergens beyond a standard screening tray is necessary for the complete evaluation of occupational and nonoccupational allergic contact dermatitis.

North American contact dermatitis group patch test results: 2011-2012.

Patch testing is an important diagnostic tool for assessment of allergic contact dermatitis (ACD). This study documents the North American Contact Dermatitis Group (NACDG) patch-testing results from January 1, 2011, to December 31, 2012. At 12 centers in North America, patients were tested in a standardized manner with a series of 70 allergens. Data were manually verified and entered into a central database. Descriptive frequencies were calculated, and trends analyzed using χ statistics. Four thousand two hundred thirty-eight patients were tested; of these, 2705 patients (63.8%) had at least 1 positive reaction, and 2029 (48.0%) were ultimately determined to have a primary diagnosis of ACD. Four hundred eight patients (9.6%) had occupationally related skin disease. There were 7532 positive allergic reactions. As compared with previous reporting periods (2009-2010 and 2000-2010), positive reaction rates statistically increased for 6 allergens: methylchloroisothiazolinone/methylisothiazolinone (5.0%; risk ratios [RRs]: 2.01 [1.60-2.52], 1.87 [1.61-2.18]), lanolin alcohol (4.6%; RRs 1.83 [1.45-2.30], 2.10 [1.79-2.47]), cinnamic aldehyde (3.9%; 1.69 [1.32-2.15], 1.53 [1.28-1.82]), glutaral (1.5%; 1.67 [1.13-2.48], 1.31 [1.00-1.71]), paraben mix (1.4%; 1.77 [1.16-2.69], 1.44 [1.09-1.92]), and fragrance mix I (12.1%; RRs 1.42 [1.25-1.61], 1.24 [1.14-1.36]). Compared with the previous decade, positivity rates for all formaldehyde-releasing preservatives significantly decreased (formaldehyde 6.6%; RR, 0.82 [0.73, 0.93]; quaternium-15 6.4% RR 0.75 [0.66, 0.85]; diazolidinyl urea 2.1%; RR, 0.67 [0.54, 0.84]; imidazolidinyl urea 1.6%, 0.60 [0.47, 0.77]; bronopol 1.6%; RR, 0.60 [0.46, 0.77]; DMDM hydantoin 1.6%; RR, 0.59 [0.54, 0.84]). Approximately a quarter of patients had at least 1 relevant allergic reaction to a non-NACDG allergen. In addition, approximately one-fourth to one-third of reactions detected by NACDG allergens would have been hypothetically missed by T.R.U.E. TEST (SmartPractice Denmark, Hillerød, Denmark). These data document the beginning of the epidemic of sensitivity to methylisothiazolinones in North America, which has been well documented in Europe. Patch testing with allergens beyond a standard screening tray is necessary for complete evaluation of occupational and nonoccupational ACD.

Occupational and Non-Occupational Allergic Contact Dermatitis: A Follow-Up Study

Background/Aims: The aim of this study was to obtain insight into the clinical course and prognosis of allergic contact dermatitis (ACD), including potential effects of genetic and environmental factors. Methods: Eighty-two patients with previously defined ACD acquired occupationally (OACD) or non-occupationally (NOACD) were patch retested and evaluated for the presence of persistent eczema, atopy and filaggrin mutations. Results: The crude risk for the persistence of a positive patch test (PT) reaction was 6.3 times higher (95% CI 3.63-11.0) for PT reactions assessed as ‘+++' compared to ‘++' reactions at the first PT. Among the categories of OACD, NOACD, age, gender, atopy, and the number of positive PT reactions at the first and second PT, only OACD (OR 10.0, 95% CI 1.95-51.2) and number of positive PT reactions at retesting (OR 3.85, 95% CI 1.57-9.44) were found to be predictors of persistent eczema. Conclusions: Occupationally acquired contact allergy was emphasized as the most important factor in predicting poor prognosis of ACD.

Occupational and non-occupational allergic contact dermatitis and quality of life: a prospective study

Attempted to evaluate and compare the impact on quality of life of occupational and non-occupational ACD and to identify the most frequently involved allergens. A quality of life questionnaire was applied. We noted moderate impact on the quality of life of both groups, without a statistical difference. Our study corroborates previous general data on the prevalence of nickel sulphate and paraphenylenediamine as the most common allergens. Potassium bichromate was shown to be one of the main occupational allergens and thimerosal as the main non-occupational allergen in our sample.

Allergic contact dermatitis to methylisothiazolinone: Exposure from baby wipes causing hand dermatitis

Methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) is a preservative used in both cosmetic and industrial settings. In Europe it is allowed to be used in rinse-off cosmetics only because of its propensity to cause allergic contact dermatitis (ACD). No such legislation exists in Australia. In recent years MI without MCI has been used. In August 2010 the first cases of MI causing non-occupational ACD were reported in Europe. The objective here was to present a case series of ACD to MI occurring in the Australian setting. : We retrospectively reviewed positive reactions to MI and MCI/MI from the Skin and Cancer Foundation patch test clinical database. MI was added to our baseline test series in January 2011. : In total 653 patients were tested for MI and there were 43 reactions, of which 23 were relevant, based on a history of exposure to MI. Seven were parents of young children with hand dermatitis caused by ACD to MI contained in baby wipes. The remaining patients reacted to MI in shampoos, conditioners, deodorants, moisturisers, a skin cleanser and a facial wipe. Three patients had ACD to MI associated with occupational exposure to hand cleansers. These data demonstrate for the first time that MI is an emerging, important allergen in both cosmetic and occupational settings in Australia. An important source of exposure was baby wipes, which was predominantly associated with hand dermatitis in parents. We believe that it is important to test for MI, not just MCI/MI, in the baseline series.

Analogues of the Epoxy Resin Monomer Diglycidyl Ether of Bisphenol F: Effects on Contact Allergenic Potency and Cytotoxicity

Diglycidyl ethers of bisphenol A (DGEBA) and bisphenol F (DGEBF) are widely used as components in epoxy resin thermosetting products. They are known to cause occupational and nonoccupational allergic contact dermatitis. The aim of this study is to investigate analogues of DGEBF with regard to contact allergy and cytotoxicity. A comprehensive knowledge of the structural features that contribute to the allergenic and cytotoxic effects of DGEBF will guide the development of future novel epoxy resin systems with reduced health hazards for those coming into contact with them. It was found that the allergenic effects of DGEBF were dependent on its terminal epoxide groups. In contrast, it was found that the cytotoxicity in monolayer cell culture was dependent not only on the presence of epoxide groups but also on other structural features.

Non-occupational Allergic Contact Dermatitis from Pyridoxine Hydrochloride and Ranitidine Hydrochloride

Non-occupational Allergic Contact Dermatitis from Pyridoxine Hydrochloride and Ranitidine Hydrochloride

Black Rubber Sensitization by Bicycle Handgrips in a Child with Palmar Hyperhidrosis

Black rubber is mainly an occupational source of contact sensitization; however, several unusual causes of non-occupational black rubber allergy are reported in the literature. A 10-year-old nonatopic Turkish boy with palmar hyperhidrosis developed acute vesicular bilateral palmar dermatitis following 2 to 3 weeks of intensive use of a new bicycle. The handgrips of the bicycle were made of black rubber. Patch testing showed a strong positive reaction to N-isopropyl-N-phenyl-4-phenylenediamine (the main sensitizer in black rubber) and questionable papular reactions to pieces of the black rubber handgrip. Additional cross-sensitization was found to p-phenylenediamine. There was no previous contact with black rubber or with any material that would contain p-phenylenediamine (eg, black henna dye). In conclusion, this was an unusual pediatric case of non-occupational allergic contact dermatitis from N-isopropyl-N-phenyl-4-phenylenediamine in black rubber bicycle handgrips. The young age of the patient and the development of contact sensitization within a relatively short period were striking. The release of the sensitizer from black rubber and the skin penetration were possibly enhanced by continuous friction and the accompanying hyperhidrosis, suggesting that the black rubber bicycle handgrip was the primary source of sensitization.

Acrylate Contact Allergy: Patient Characteristics and Evaluation of Screening Allergens

Acrylates are present in a wide variety of products and cause occupational and non-occupational allergic contact dermatitis. There is no clear guidance from the literature as to which allergens should be used for patch-test screening for acrylates. To characterize patients with contact allergy to acrylates and to evaluate the allergens used to screen for acrylate allergy. Charts of patients visiting an outpatient contact dermatitis clinic from January 1998 to February 2008 were reviewed retrospectively. Forty-four patients were found to have contact allergy to acrylates. The most commonly positive allergens were hydroxyethyl methacrylate (HEMA), ethyl acrylate (EA), and methyl methacrylate (MMA). Thirty-two of the 44 positive patch-test results (73%) would have been discovered with the use of the two compounds (MMA, EA) in the North American Standard Series (Chemotechnique screening series), a commercially available screening series, while 12 were found through expanded patch testing. Artificial nails, dental materials, and adhesives were the most common exposures. Occupational relevance was found in 18 cases, including those of dental workers, assemblers, and aestheticians. Acrylates are an important cause of contact allergy. Screening series identify most cases of acrylate allergy but miss a substantial number. Clinicians should remain vigilant for acrylate allergy even if initial screening is negative.

Dermatitis alérgica de contacto no profesional a propóleo

Abstract—Propolis is produced by bees from the resinous secretion of some vegetal species. Allergic contact dermatitis from propolis was originally reported as an occupational disease affecting beekeepers but today involves patients who use «natural» products containing propolis with cosmetic or therapeutical purposes.A case of nonoccupational allergic contact dermatitis from propolis affecting a 44-year-old woman is reported. The patient treated a labial herpes simplex with a solution containing propolis. Some hours later she developed an acute dermatitis on the lip and perioral area. Patch test with the commercial propolis solution was very positive (+ + +) at 48 and 96 hours. Patch test with True Test® showed a positive reaction to balsam of Peru among others. This result may be due to cross reaction, since balsam of Peru shares some components with propolis.The increasing use of topical products marketed as natural cosmetics and drugs could induce a higher frequency of sensitization to propolis in Spain.

Epidemiological survey of contact dermatitis in Italy (1984–1993) by GIRDCA (Gruppo Italiano Ricerca Dermatiti da Contatto e Ambientali)

Background: The Gruppo Italiano Ricerca Dermatiti da Contatto e Ambientali (GIRDCA) resolved to obtain the most relevant data regarding contact dermatitis (CD) in Italy by means of a multicenter epidemiological study, involving research units (RU) throughout the country. The survey was performed with the collaboration of Generale Per l'Informatica, Rome (GEPIN) over the periods 1984 to 1988 and 1989 to 1993. The analytical study (of a transverse kind) was aimed at supplying prevalence measures. Materials and methods: The number of subjects taking part in the survey was 42,839. All patients underwent patch testing with the GIRDCA standard series and were included in the survey only if the final diagnosis was either CD or eczematous dermatitis caused by contact. The main anamnestic, clinical data, and allergological test results of all patients were codified into a chart, and subsequently transcribed into a data bank. The data were then processed cumulatively and were statistically analysed by a chi-square for trend test. Results: The four most frequent diagnoses (which, when considered together, make up 39,496 cases, or about 92% of all cases) proved to be nonoccupational allergic contact dermatitis (ACD), nonoccupational irritant contact dermatitis (ICD), occupational ACD, and occupational ICD. The haptens most frequently causing positive reactions in the total number of cases over the first 5 years were, in order of frequency: nickel sulphate, potassium dichromate, cobalt chloride, fragrance mix, balsam of Peru, and, in the second 5-year period, nickel sulphate, cobalt chloride, potassium dichromate, fragrance mix, and thimerosal. Occupational CD (ACD and ICD) was present in 11,694 cases overall, corresponding to approximately 27% of the total number of cases examined, and approximately 29% of all CD (including forms of nonoccupational CD). Regarding distribution by sex, a substantial equivalence of males and females for ACD, and a prevalence of females with ICD can be observed. Five occupations were reputed to be responsible for over 60% of total cases of occupational CD (housewives, bricklayers, workers in the metallurgic and mechanical industries, hairdressers, and healthcare personnel). Regarding the pathogenesis, a clearly dominant percentage of ACD may be observed among bricklayers and hairdressers, and of ICD among housewives. The haptens most frequently noted over the entire decade as the cause of positive reaction in occupational ACD were, in order of frequency, potassium dichromate, nickel sulphate, cobalt chloride, p-phenylenediamine and thiuram mix. Nonoccupational CD (ACD and ICD) was present in 27,802 cases overall, corresponding to about 65% of all cases under examination and over 70% of all CD (also including forms of occupational CD). In regard to distribution by sex, a clear dominance of females, as opposed to males, can be noted for ACD and also (although to a lesser extent) for ICD. The main products and materials (ie, components and relative substances) that are pinpointed as being responsible for nonoccupational ACD, were, in order of frequency, clothing accessories, cosmetics, topical pharmaceuticals, and clothing. The haptens most frequently recognized as the cause of positive reactions were, in order of frequency, nickel sulphate, fragrance mix, cobalt chloride, balsam of Peru, potassium dichromate, ethylenediamine, and diaminodiphenylmethane.