Contact allergy to oxidised geraniol may be over-represented in individuals with photocontact allergy to ketoprofen

BACKGROUND

Simultaneous overrepresentations of contact allergies and photocontact allergies are common in individuals with photocontact allergy to ketoprofen.

AIMS

To investigate whether contact allergy to oxidised (ox.) geraniol, geraniol, geranial, neral and citral is overrepresented in individuals with photocontact allergy to ketoprofen.

METHODS

The contact allergy rates to ox. geraniol, geraniol, geranial, neral and citral in routinely patch tested dermatitis patients were compared with the corresponding rates in individuals with photocontact allergy to ketoprofen.

RESULTS

Allergic patch test reactions were noted to ox. geraniol 11% (n = 39, 5.8%), ox. geraniol 6% (n = 12, 1.8%), geraniol 6% (n = 2, 0.3%), geranial (n = 18, 2.7%), neral (n = 7, 1.0%) and citral (n = 15, 2.2%). In those four patients who were diagnosed with photocontact allergy to ketoprofen during the test period, a significant overrepresentation (p = 0.020) of simultaneous contact allergy to ox. geraniol 11% was demonstrated. Overrepresentation of simultaneous contact allergy to various combinations of ox. geraniol, ox. limonene and ox. linalool was also noted in ketoprofen-photoallergic patients.

CONCLUSIONS

Contact allergy to ox. geraniol, geranial and citral is common in routinely tested dermatitis patients. There is an overrepresentation of simultaneous contact allergy to ox. geraniol, ox. limonene and ox. linalool in patients with photocontact allergy to ketoprofen.

Analysis of Hexavalent Chromium in Cement Samples From Countries Within and Outside the EU: A Study From the International Contact Dermatitis Research Group

Background: Allergic contact dermatitis (ACD) caused by hexavalent chromium (Cr(VI)) is often severe and difficult to treat. The content of Cr(VI) in cement can be reduced by, for example, addition of iron(II) sulfate. Since 2005 the content of Cr(VI) in cement is regulated in the EU Directive 2003/53/EC and must not exceed 2 ppm. Since this regulation came into force, ACD caused by cement has markedly been reduced. Objective: To investigate Cr(VI) and total chromium content in samples of cement from countries within and outside the EU. Methods: The members of the International Contact Dermatitis Research Group (ICDRG) were invited to participate in the study with the aim to collect cement samples from geographically different areas. The content of Cr(VI) in the samples was estimated by the diphenyl carbazide spot test, atomic absorption spectroscopy was used to assess the total chromium content. Results: Forty-five cement samples were analyzed, containing amounts of Cr(VI) from <0.1 to >70 ppm. Twenty-one samples contained >2 ppm Cr(VI), 24 contained less. Four of 17 samples from within the EU contained >2 ppm Cr(VI), that is, higher amounts than stipulated in the EU directive, as compared with 17 samples from countries outside the EU. Conclusion: In countries outside the EU, significantly more cement samples contained >2 ppm Cr(VI).

Patch test results to extracts of synthetic garments in textile dye positive patients

BACKGROUND

Disperse dyes (DDs) are the most prevalent causes of textile-related allergic contact dermatitis and are used for coloring synthetic textile materials based on fibers such as polyester, acrylic, acetate and polyamide. Eight DDs are included in a textile dye mix (TDM) 6.6% petrolatum (pet.) in the European baseline patch test series.

OBJECTIVES

The aim of this study was to patch test TDM 6.6% pet. Positive individuals with the extracts of synthetic fiber clothes that do not contain any of the pure DDs present in the TDM 6.6% to study the reactivity pattern.

METHODS

Seventy-three TDM-positive former patients tested between 2012-2017 at the Department of Occupational and Environmental Dermatology in Malmö, Sweden were invited to join the study, 10 participated. Twenty-four textile items (collected in 9 countries in Europe, Asia and North America in 2012) were extracted in dichloromethane. The TDM 6.6% was patch tested simultaneously with the 24 textile item preparations in petrolatum made from the extracts. Prior to patch testing the participants filled the 7-question questionnaire regarding possible symptoms from textile exposure.

RESULTS

Ten individuals, agreed to join the study. Eight of them reacted to TDM 6.6%. Nine participants reacted to 20 of 24 extracts. One reacted to 19 extracts, another to 14, 3 to 5 extracts, 1 to 4, 1 to 3 extracts and 2 to 2 extracts. One was negative to all tested preparations including TDM 6.6%. The participants mainly reacted to 6 textile extracts. All controls tested negatively to tested extracts. Four individuals of the 10 TDM-allergic individuals previously had had problems after wearing clothes. Four out of the 10 participants had had atopic eczema in childhood. All women had dyed their hair with permanent hair dyes but none of the males.

CONCLUSION

TDM - positive patients react to textile extracts made from synthetic garments, even if they do not contain any of the pure DDs present in TDM 6.6%. More studies are needed to pin-point the culprit haptens in these extracts.

Contact allergy to fragrance mix I and its components in individuals with photocontact allergy to ketoprofen

BACKGROUND

Contact allergy to fragrance mix I (FM I) is over-represented in patients photoallergic to ketoprofen. The prevalence of contact allergy to two components of FM I, cinnamal and cinnamyl alcohol, in ketoprofen-photoallergic patients is higher than in dermatitis patients.

OBJECTIVE

To explore the prevalence of contact allergy to FM I and its individual components in patients with photocontact allergy to ketoprofen, and to compare with a dermatitis and the general population.

METHODS

Data on patch and photopatch tests performed between 2009-2018 were collected. Ketoprofen-photoallergic patients were compared with dermatitis patients and published data on the general population regarding the prevalence and the distribution of contact allergy to FM I and its components.

RESULTS

A higher prevalence of contact allergy to cinnamyl alcohol compared with cinnamal (23.3% vs 10.0%), and eugenol compared with isoeugenol (23.3% vs 6.7%), was observed in ketoprofen-photoallergic patients, while the relationship was the opposite in the dermatitis group (0.7% vs 1.05%; 0.4% vs 0.9%). The overall prevalence of contact allergy to several components of FM I was significantly higher in ketoprofen-photoallergic patients.

CONCLUSIONS

Contact allergy to FM I and many of its components is over-represented in patients photoallergic to ketoprofen compared with dermatitis patients and the general population.

Oral provocation of patients allergic to sesquiterpene lactones with German chamomile tea to demonstrate possible systemic allergic dermatitis

BACKGROUND

Most patients with contact allergy to Asteraceae plants are patch test positive to sesquiterpene lactone mix (SLM). There are several reports among these patients of a flare-up of hand eczema after ingestion of food and beverages originating from Asteraceae plants.

AIM

To investigate whether German chamomile tea can elicit systemic allergic dermatitis.

PATIENTS AND METHODS

Individuals with or without contact allergy to SLM were patch tested with an extract of German chamomile tea. Six weeks later, they were provoked with capsules containing either freeze-dried German chamomile tea or placebo capsules containing lactose, in a double-blind, randomized study. A numerical rating scale (NRS) was used to ascertain the volunteers' opinion of their hand eczema status. The study individuals were examined to detect a possible flare-up of healed patch test reactions to chamomile.

RESULTS

None of the subjects had a flare-up of healed patch test reactions. According to the NRS, SLM-positive individuals experienced a significant worsening of hand eczema, independently of whether they received chamomile or lactose capsules.

CONCLUSION

No evidence suggestive of systemic allergic dermatitis was found.

Skin application of glutathione and iron sulfate can inhibit elicitation of allergic contact dermatitis from hexavalent chromium

BACKGROUND

Allergic contact dermatitis (ACD) caused by hexavalent chromium, Cr(VI), is often severe and difficult to treat. The most common source of exposure to Cr(VI) in Sweden used to be cement, and more recently leather. The contact allergy can be diminished or inhibited if the exposure is decreased or ceases. Barrier creams against different kinds of allergens have been investigated for their protective properties which may offer protection against Cr(VI) exposure.

OBJECTIVES

To investigate the capacity of formulas containing glutathione (GSH) and iron sulfate to inhibit elicitation of ACD in Cr(VI)-allergic individuals when exposed to Cr(VI).

METHODS

In 18 Cr(VI)-allergic volunteers the back was divided into eight patch test areas which were treated with preparations of possible barrier creams, prior to patch testing with a dilution series of potassium dichromate and a buffered extract of cement.

RESULTS

A significant reduction in reactivity to Cr(VI) and cement extract on skin treated with formulas containing GSH or iron sulfate was noticed, compared with untreated skin.

CONCLUSION

Formulas containing GSH or iron sulfate in barrier creams inhibit ACD in individuals allergic to Cr(VI) when applied before exposure to Cr(VI) and cement extract.

Can reducing cosmetic substances help prevent chromate contact allergy?

BACKGROUND

Allergic contact dermatitis caused by Cr(VI) is often severe and difficult to treat. Therefore, primary prevention is a main goal but, secondary prevention can be valuable to ease the symptoms or prevent relapse of Cr(VI) dermatitis when sensitization has occurred. Barrier creams have been tried for many chemical substances, but until now there is no successful barrier cream against Cr(VI).

OBJECTIVES

To investigate the ability of reducing agents to transform Cr(VI) into Cr(III) in an experimental situation, in order to find suitable chemicals to investigate for possible use in a barrier cream.

METHODS

The capacity to reduce the amount of Cr(VI) was analyzed in water solutions of acetylcysteine, cysteine, dihydroxyacetone, glutathione, and iron sulfate heptahydrate. Thereafter the reducing capacity of acetylcysteine, dihydroxyacetone, glutathione, and iron sulfate on the amount of Cr(VI) in cement extracts was investigated. The content of Cr(VI) in the test solutions and in the cement extracts was estimated by the diphenyl carbazide spot test.

RESULTS

All of the chosen chemicals reduced the amount of Cr(VI) in the test solutions and in the cement extracts to some extent. The reducing capacity was most prominent for iron sulfate.

CONCLUSION

A reducing capacity was found for all chosen chemicals.

Solvent Orange 60 is a potent contact sensitizer in occupational and everyday life

BACKGROUND

Solvent Orange (SO) 60 is a perinone-type dye that is often used in plastic materials such as spectacle frames and has been shown to cause contact allergy. The first case of SO 60 allergic contact dermatitis caused by spectacle frames was reported in 1999, and the second in 2011. We have recently seen 10 patients, of whom 6 developed dermatitis in the retroauricular/temporal area after wearing plastic spectacles.

OBJECTIVES

To report the cause of the dermatitis in the 10 patients and to describe our first case with occupational SO 60 contact allergy.

METHODS

In this retrospective study, patch test results of 10 patients, tested with the Swedish baseline series and our specific spectacle and/or plastic series, including SO 60 1.0% pet., in 2011-2017 were analysed.

RESULTS

Ten patients, 2 males and 8 females, aged 43 to 71 years, reacted positively to SO 60 1.0% pet., namely, 4 pensioners, 2 nurses, 1 office worker, 1 teacher, 1 shop assistant, and 1 unemployed person. Four of the patients had an atopic history. Patch test reactions varied from + to +++; some had spread >20 cm outside the test area in terms of erythematous, infiltrated skin with papules. Retesting of patient no. 1 with serial dilutions of SO 60 in acetone showed positive reactions down to 1 ppm. Three patients reacted to the extracts of their earpieces. Gas chromatography-mass spectrometry was used to confirm the presence of SO 60 in 2 earpieces.

CONCLUSIONS

SO 60 should be included in any spectacle patch test series that may be used. If there is a strong suspicion of contact allergy to SO 60 before patch testing, lowering the test concentration from 1.0% to 0.01% should be considered.

A retrospective investigation of hexavalent chromium allergy in southern Sweden

BACKGROUND

Historically, allergic contact dermatitis caused by hexavalent chromium [Cr(VI)] in cement was the most common cause of invalidity attributable to skin disease in Sweden. Since the legislation to reduce Cr(VI) in cement was introduced in 1989, we rarely see allergic contact dermatitis caused by cement.

OBJECTIVES

To examine the frequency of contact allergy to Cr(VI) in southern Sweden in 2005-2014.

METHODS

We investigated the occurrence of positive reactions to potassium dichromate 0.5% pet. in consecutively tested dermatitis patients, and compared the occurrence of atopic dermatitis, localization of dermatitis and simultaneous positive reactions to cobalt chloride and nickel sulfate in the Cr(VI)-positive patients with those in a group of patients with a similar age and sex distribution.

RESULTS

In total, 6482 patients were tested, and 233 Cr(VI)-allergic individuals were found (3.6%). A significantly higher proportion of atopic dermatitis was found among Cr(VI)-allergic patients, and a significantly higher share of foot dermatitis was found among Cr(VI)-allergic women, than among controls. Cr(VI) allergy was less likely when both nickel allergy and cobalt allergy were present.

CONCLUSION

A relatively high frequency of contact allergy to Cr(VI) was found. The cause has shifted from cement exposure to other exposures, probably mainly leather.

Sensitizing Capacities and Cross-Reactivity Patterns of Some Diisocyanates and Amines Using the Guinea-Pig Maximization Test. Can p-phenylenediamine be Used as a Marker for Diisocyanate Contact Allergy?

Background:

Isocyanates are mainly considered respiratory allergens but can also cause contact allergy. Diphenylmethane-4,4′-diamine (4,4′-MDA) has been considered a marker for diphenylmethane-4,4′-diisocyanate (4,4′-MDI) contact allergy. Furthermore, overrepresentation of positive patch-test reactions top-phenylenediamine (PPD) in 4,4′-MDA positive patients have been reported.

Objectives:

To investigate the sensitizing capacities of toluene-2,4-diisocyanate (2,4-TDI) and PPD and the cross-reactivity of 4,4′-MDA, 2,4-TDI, dicyclohexylmethane-4,4′-diamine (4,4′-DMDA), dicyclohexylmethane-4,4′-diisocyanate (4,4′-DMDI), 4,4′-MDI and PPD.

Methods:

The Guinea Pig Maximization Test (GPMT) was used.

Results:

PPD was shown to be a strong sensitizer (p<0.001). Animals sensitized to PPD showed cross-reactivity to 4,4′-MDA (p<0.001). Animals sensitized to 4,4′-MDA did not show cross-reactivity to PPD. 8 animals sensitized to 2,4-TDI were sacrificed due to toxic reactions at the induction site and could thus not be fully evaluated.

Conclusion:

PPD was shown to be a strong sensitizer. However, it cannot be used as a marker for isocyanate contact allergy. On the other hand, positive reactions to 4,4′-MDA could indicate a PPD allergy. The intradermal induction concentration of 2,4-TDI (0.70% w/v) can induce strong local toxic reactions in guinea-pigs and should be lowered.

Sensitization and cross-reactivity patterns of contact allergy to diisocyanates and corresponding amines: investigation of diphenylmethane-4,4'-diisocyanate, diphenylmethane-4,4'-diamine, dicyclohexylmethane-4,4'-diisocyanate, and dicylohexylmethane-4,4'-diamine

Background

Isocyanates are used in polyurethane production. Dermal exposure to isocyanates can induce contact allergy. The most common isocyanate is diphenylmethane diisocyanate used for industrial purposes. The isomer diphenylmethane‐4,4′‐diisocyanate (4,4′‐MDI) is used in patch testing. Diphenylmethane‐4,4′‐diamine (4,4′‐MDA) is its corresponding amine. Concurrent reactions to 4,4′‐MDI and 4,4′‐MDA have been reported, as have concurrent reactions to 4,4′‐MDI and dicyclohexylmethane‐4,4′‐diisocyanate (4,4′‐DMDI).

Objectives

To investigate the sensitization capacities and the cross‐reactivity of 4,4′‐MDI, 4,4′‐MDA, 4,4′‐DMDI, and dicyclohexylmethane‐4,4′‐diamine (4,4′‐DMDA).

Methods

The guinea‐pig maximization test (GPMT) was used.

Results

The GPMT showed sensitizing capacities for all investigated substances: 4,4′‐MDI, 4,4′‐MDA, 4,4′‐DMDI, and 4,4′‐DMDA (all p < 0.001). 4,4′‐MDI‐sensitized animals showed cross‐reactivity to 4,4′‐MDA (p < 0.001) and 4,4′‐DMDI (all p < 0.05). 4,4′‐MDA‐sensitized animals showed cross‐reactivity to 4,4′‐DMDA (p = 0.008).

Conclusion

All of the investigated substances were shown to be strong sensitizers. Animals sensitized to 4,4′‐MDI showed cross‐reactivity to 4,4′‐MDA and 4,4′‐DMDI, supporting previous findings in the literature. The aromatic amine 4,4′‐MDA showed cross‐reactivity to the aliphatic amine 4,4′‐DMDA.

Two sensitizing oxidation products of p-phenylenediamine patch tested in patients allergic to p-phenylenediamine

BACKGROUND

The results from a previous study indicated the presence of several possible sensitizers formed during oxidation of the potent sensitizer p-phenylenediamine (PPD) to which PPD-sensitized patients might react, in various patterns.

OBJECTIVES

To extract and analyse a yellow spot from a thin-layer chromatogram with oxidized PPD, to which 6 of 14 (43%) PPD-positive patients had reacted in a previous study, in order to identify potential sensitizer(s) and to patch test this/these substance(s) in the 14 PPD-positive patients.

METHODS

The yellow spot was extracted from a thin-layer chromatogram of oxidized PPD, and two substances, suspected to be allergens, were identified by analysis with gas chromatography mass spectrometry (GCMS). The 14 PPD-positive patients, who had been previously tested with the thin-layer chromatogram of oxidized PPD, participated in the investigation, and were tested with dilutions of the two substances.

RESULTS

GCMS analysis identified 4-nitroaniline and 4,4'-azodianiline in the yellow spot. Of the 14 PPD-positive test patients, 5 (36%) reacted to 4-nitroaniline and 9 (64%) reacted to 4,4'-azodianiline.

CONCLUSION

The results show that 4-nitroaniline and 4,4'-azodianiline, formed during oxidation of PPD, are potent sensitizers. PPD-sensitized patients react to a high extent to concentrations equimolar to PPD of 4-nitroaniline and 4,4'-azodianiline.

Outbreak of eczema and rhinitis in a group of office workers in Greenland

INTRODUCTION

Disturbed indoor climate may in some cases be associated with illness. In the present paper, we report the results from a thorough investigation of office workers in Greenland, who developed skin and/or airway problems after moving into renewed offices.

MATERIAL AND METHODS

In 2009 the office of the Bank of Greenland had a total renovation of the building, including new furniture and carpets. Symptoms developed within the first year after moving back into the renewed buildings. After removal of carpets in the building, symptoms significantly improved. Workers were examined in 2009 and re-examined in 2013, including clinical examination, patch test and when relevant also skin prick tests and histamine release test. Isothiazolinones and fumarates, both able to cause airway as well as skin symptoms, were isolated from carpets before testing, and included in the test series.

RESULTS

In total, 32 out of 80 workers (40%) developed symptoms; 27 reported eczema, 20 rhinitis and 4 urticaria. Eczema was located on the hands and/or lower arms in 18 workers, on the face in 10 workers and on legs/trunk in 12 workers. After intervention in the office, 22 workers with eczema reported significant improvement, all cases of hand eczema cleared and 16 workers with rhinitis also improved. Positive patch tests to carpet extracts were found significantly more frequent in the worker cohort than in a control group comprising 47 dermatitis patients (p<0.001). Only few workers reacted with a positive response to skin prick test or in the HR test, no obvious pattern in reactions was found, and no conclusions can be made from these reactions.

CONCLUSION

The results indicate that the reported symptoms are related to exposures from the building after renovation in 2009. A specific triggering exposure could not be identified, although chemicals from the glued carpets are suspected. The study is an example of a work place investigation, and illustrates the diversity of symptoms and exposures involved in "Sick Building" cases.

Isobornyl acrylate: an impurity in alkyl glucosides

CONTEXT

Alkyl glucosides and alkyl poly-glucosides are widely used as wetting agents, surfactants and emulsifiers in several industrial and cosmetic products. They are known as well-tolerated and are usually added to the primary surfactants in order to reduce the irritating potential of the main foaming agents.

OBJECTIVE

Recently, some authors suggested that allergic contact dermatitis to alkyl glucosides might be more frequent than suspected. On the other hand, the chemical structures of glucosides do not show potentially allergenic chemical groups or strongly polarized structures. The aim of our study is to investigate alkyl glucosides carrying out a detailed chemical analysis on samples of raw materials to identify potentially allergenic impurities or by-products contained in commercial samples of alkyl glucosides.

MATERIALS AND METHODS

We chemically analyzed samples of cocoyl glucoside, decyl glucoside and lauryl glucoside by three different analytical methods, in order to identify any undesired or polluting substances.

RESULT

In each of the three samples, we detected the presence of isobornyl acrylate. Its approximate content in the tested samples is 500 ng/g of the product.

DISCUSSION

Isobornyl acrylate is not used in the synthesis of alkyl glucosides, but as a plasticizer in many plastic materials. It can be easily released to materials flowing over these surfaces when they have high extraction power, as glucosides.

CONCLUSION

Isobornyl acrylate may play a role as hidden allergen, in the form of an impurity collected during the industrial process, explaining some cases of allergic reaction to alkyl glucosides.

Are gloves sufficiently protective when hairdressers are exposed to permanent hair dyes? An in vivo study

BACKGROUND

The use of permanent hair dyes exposes hairdressers to contact allergens such as p-phenylenediamine (PPD), and the preventive measures are insufficient.

OBJECTIVES

To perform an in vivo test to study the protective effect of gloves commonly used by hairdressers.

PATIENTS/MATERIALS/METHODS

Six gloves from Sweden, Italy and Germany were studied: two vinyl, one natural rubber latex, two nitrile, and one polyethylene. The hair dye used for the provocation was a dark shade permanent dye containing PPD. The dye was mixed with hydrogen peroxide, and 8 PPD-sensitized volunteers were tested with the gloves as a membrane between the hair dye and the skin in a cylindrical open chamber system. Three exposure times (15, 30 and 60 min) were used.

RESULTS

Eczematous reactions were found when natural rubber latex, polyethylene and vinyl gloves were tested with the dye. The nitrile gloves gave good protection, even after 60 min of exposure to the hair dye.

CONCLUSIONS

Many protective gloves used by hairdressers are unsuitable for protection against the risk of elicitation of allergic contact dermatitis caused by PPD.

Usage tests of oak moss absolutes containing high and low levels of atranol and chloroatranol

Atranol and chloroatranol are strong contact allergens in oak moss absolute, a lichen extract used in perfumery. Fifteen subjects with contact allergy to oak moss absolute underwent a repeated open application test (ROAT) using solutions of an untreated oak moss absolute (sample A) and an oak moss absolute with reduced content of atranol and chloroatranol (sample B). All subjects were in addition patch-tested with serial dilutions of samples A and B. Statistically significantly more subjects reacted to sample A than to sample B in the patch tests. No corresponding difference was observed in the ROAT, though there was a significant difference in the time required to elicit a positive reaction. Still, the ROAT indicates that the use of a cosmetic product containing oak moss absolute with reduced levels of atranol and chloroatranol is capable of eliciting an allergic reaction in previously sensitised individuals.

Patch testing with serial dilutions and thin-layer chromatograms of oak moss absolutes containing high and low levels of atranol and chloroatranol

BACKGROUND

Oak moss absolute (Evernia prunastri extract) contains a large number of substances, among them the potent allergens atranol and chloroatranol. Since 2008, their content in oak moss absolute has been restricted by the International Fragrance Association to a maximum level of 100 ppm each.

OBJECTIVES

To compare the elicitation capacities of a traditional (sample A) and a treated (sample B) oak moss absolute containing, in total, 27 000 and 66 ppm of atranol and chloroatranol, respectively, and to investigate reactions to components of oak moss absolute separated by thin-layer chromatography (TLC).

METHODS

Fifteen oak moss-allergic subjects were patch tested with serial dilutions and TLC strips of samples A and B.

RESULTS

Fifteen subjects reacted to sample A at concentrations ≤ 2.0%, and 2 subjects reacted to sample B at 2.0% but not to lower concentrations. Among 13 subjects reacting to the TLC strip of sample A, 11 reacted to spots with retardation factor values corresponding to those of atranol and/or chloroatranol, and 11 reacted to other areas on the TLC strip. Only one subject reacted to the TLC strip of sample B.

CONCLUSIONS

The patch test reactivity of sample B was significantly lower than that of sample A. The TLC patch tests indicate the presence of sensitizers other than atranol and chloroatranol in oak moss absolute.

Stability of fragrance patch test preparations applied in test chambers

BACKGROUND

Petrolatum patch test preparations are for practical reasons often applied in test chambers in advance, several hours or even days before the patient is tested. As many fragrance compounds are volatile it may be suspected that petrolatum preparations applied in test chambers are not stable over time.

OBJECTIVES

To investigate the stability of petrolatum preparations of the seven chemically defined components in the fragrance mix (FM I) when stored in test chambers.

METHODS

Samples of petrolatum preparations applied in test chambers stored at room temperature and in a refrigerator for between 4 and 144 h were analysed using liquid chromatographic methods.

RESULTS

The concentration decreased by ≥ 20% within 8 h in four of seven preparations stored in Finn chambers at room temperature. When stored in a refrigerator only the preparation of cinnamal had decreased by ≥ 20% within 24 h. The stability of preparations of cinnamal stored in IQ chambers with a plastic cover was slightly better, but like the preparations applied in Finn chambers, the concentration decreased by ≥ 20% within 4 h at room temperature and within 24 h in a refrigerator. Cinnamal and cinnamyl alcohol were found to be more stable when analysed as ingredients in FM I compared with when analysed in individual preparations.

CONCLUSIONS

Within a couple of hours several fragrance allergens evaporate from test chambers to an extent that may affect the outcome of the patch test. Application to the test chambers should be performed as close to the patch test occasion as possible and storage in a refrigerator is recommended.

Several cases of work-related allergic contact dermatitis caused by isocyanates at a company manufacturing heat exchangers

BACKGROUND

A 43-year-old woman was referred by her occupational health service with suspected occupational contact dermatitis. In connection with the investigation, a workplace visit was undertaken at her company, which used an adhesive based on pre-polymeric diphenylmethane diisocyanate in one of its units. During the visit, we became aware of six other employees with skin problems who were then referred to our department for investigation.

OBJECTIVES

To investigate the seven employees complaining about skin problems.

METHODS

Seven employees were patch tested with a baseline series, an isocyanate series, and a series with work material.

RESULTS

Five of seven patients had occupational contact allergy. Four reacted to isocyanate-related test preparations, and one to a cleanser used at the workplace.

CONCLUSIONS

Workplace visits constitute an important part of an occupational investigation, as they might give a broader picture of the problems at a company. In this case, it was found that 5 of 100 employees currently had or had previously had occupation-related skin problems. Owing to 'healthy worker selection', some of these patients might have been missed if we had not performed a full-scale workplace visit.

Textile dyes Disperse Orange 1 and Yellow 3 contain more than one allergen as shown by patch testing with thin-layer chromatograms

BACKGROUND

It is known that some patch-test preparations containing disperse dyes contain impurities with unknown relevance for the development or elicitation of contact allergy.

OBJECTIVE

To evaluate the significance of the impurities found in the commercial dyes Disperse Orange 1 (DO1) and Disperse Yellow 3 (DY3) regarding contact allergy in patients with known sensitivity to them.

METHODS

Ten patients allergic to DY3 and/or DO1 were tested with a dilution series of commercial and purified DY3 and DO1 (with water-soluble parts prepared from the commercial dyes) and with naphthalene sulfonate. Nine patients were additionally tested with thin-layer chromatograms (TLCs) made from the commercial DO1 and DY3 and with paper chromatograms made from the water-soluble part of these dyes.

RESULTS

Eight of nine and three of six patients tested positively to the TLCs of DO1 and DY3, respectively. Among them, 4 of 8 and 2 of 3 patients, respectively, were positive also to another spot on the TLCs. One patient was positive to the paper chromatogram from the water-soluble part of DO1. None of the tested patients reacted to naphthalene sulfonate.

CONCLUSION

The results of our study suggest that there are more relevant allergens in the fat-soluble and water-soluble fractions of the commercial disperse dyes.

Dermal uptake study with 4,4'-diphenylmethane diisocyanate led to active sensitization

BACKGROUND

To investigate the dermal uptake of 4,4'-diphenylmethane diisocyanate (4,4'-MDI), a study was performed in which 2 female volunteers were exposed to 10 and 25 mg, respectively, of 4,4'-MDI by applying 2.0% 4,4'-MDI in petrolatum over areas where the surface concentration corresponded to 800 µg/cm(2) . Ten days later, they developed eczematous dermatitis at the area of application.

OBJECTIVES

To investigate whether the dermal application caused active sensitization to 4,4'-MDI.

METHODS

Chemical analysis of the 4,4'-MDI preparation used in the application and the amount of 4,4'-MDI not absorbed by the skin was performed with liquid chromatography-mass spectrometry. The volunteers were tested with serial dilutions of 4,4'-MDI and the potentially cross-reacting substances 4,4'-diaminodiphenylmethane (4,4'-MDA), p-phenylenediamine (PPD), and dicyclohexylmethane-4,4'-diisocyanate (DMDI).

RESULTS

Patch test results suggested that the volunteers were actively sensitized to 4,4'-MDI following the dermal uptake study, as they reacted positively to 4,4'-MDA, a marker for 4,4'-MDI allergy. No positive reactions were seen to PPD or DMDI. Chemical investigation confirmed that the correct concentration had been used for the dermal uptake study, and showed that about 70% of the applied 4,4'-MDI was not absorbed.

CONCLUSIONS

A dermal uptake study with 4,4'-MDI in 2.0% pet. with an occlusion time of 8 hr induced active sensitization to 4,4'-MDI and subsequently to 4,4'-MDA.

Patch testing with a textile dye mix in a baseline series in two countries

Disperse dyes are the most common contact sensitizers among textile dyes. The main aim of this study was to investigate the outcome of patch testing with a textile dye mix 6.6%. A total of 2,049 patients from Sweden and 497 from Belgium were tested with the mix, consisting of Disperse (D) Blue 35, D Yellow 3, D Orange 1 and 3, D Red 1 and 17, 1.0% each, and D Blue 106 and D Blue 124, 0.3% each. Of the total number, 65 patients, 2.6%, tested positively to the mix, 4.2% of the Belgian patients and 2.1% of the Swedish patients. Patch testing with the mix 6.6% revealed significantly more patients with contact allergy compared with testing with a previous mix 3.2% (p < 0.01). Contact allergy to the mix was significantly more common in the Belgian than in the Swedish patients.