Contact allergy in Swedish professional ice hockey players

BACKGROUND

Professional ice hockey players may contract irritant and allergic contact dermatitis.

AIMS

To investigate the presence of contact allergy (CA) in professional ice hockey players in Sweden.

METHODS

Ten teams from the two top leagues were assessed for potential occupational exposure to sensitizers. Exactly 107 players were patch tested with an extended baseline series and a working series, in total 74 test preparations. The CA rates were compared between the ice hockey players and controls from the general population and dermatitis patients.

RESULTS

One out of 4 players had at least one contact allergy. The most common sensitizers were Amerchol L 101, nickel and oxidized limonene. CA was as common in the ice hockey players as in dermatitis patients and significantly more common than in the general population. Fragrances and combined sensitizers in cosmetic products (fragrances + preservatives + emulsifier) were significantly more common in ice hockey players compared with the general population.

CONCLUSION

The possible relationship between CA to fragrances and cosmetic products on the one hand and the presence of dermatitis on the other should be explored further.

Hexavalent chromium still a concern in Sweden - Evidence from a cross-sectional study within the SafeChrom project

OBJECTIVES

Hexavalent chromium (Cr(VI)) is classified as a human carcinogen. Occupational Cr(VI) exposure can occur during different work processes, but the current exposure to Cr(VI) at Swedish workplaces is unknown.

METHODS

This cross-sectional study (SafeChrom) recruited non-smoking men and women from 14 companies with potential Cr(VI) exposure (n = 113) and controls from 6 companies without Cr(VI) exposure (n = 72). Inhalable Cr(VI) was measured by personal air sampling (outside of respiratory protection) in exposed workers. Total Cr was measured in urine (pre- and post-shift, density-adjusted) and red blood cells (RBC) (reflecting Cr(VI)) in exposed workers and controls. The Bayesian tool Expostats was used to assess risk and evaluate occupational exposure limit (OEL) compliance.

RESULTS

The exposed workers performed processing of metal products, steel production, welding, plating, and various chemical processes. The geometric mean concentration of inhalable Cr(VI) in exposed workers was 0.15 μg/m3 (95% confidence interval: 0.11-0.21). Eight of the 113 exposed workers (7%) exceeded the Swedish OEL of 5 μg/m3, and the Bayesian analysis estimated the share of OEL exceedances up to 19.6% for stainless steel welders. Median post-shift urinary (0.60 μg/L, 5th-95th percentile 0.10-3.20) and RBC concentrations (0.73 μg/L, 0.51-2.33) of Cr were significantly higher in the exposed group compared with the controls (urinary 0.10 μg/L, 0.06-0.56 and RBC 0.53 μg/L, 0.42-0.72). Inhalable Cr(VI) correlated with urinary Cr (rS = 0.64) and RBC-Cr (rS = 0.53). Workers within steel production showed the highest concentrations of inhalable, urinary and RBC Cr. Workers with inferred non-acceptable local exhaustion ventilation showed significantly higher inhalable Cr(VI), urinary and RBC Cr concentrations compared with those with inferred acceptable ventilation. Furthermore, workers with inferred correct use of respiratory protection were exposed to significantly higher concentrations of Cr(VI) in air and had higher levels of Cr in urine and RBC than those assessed with incorrect or no use. Based on the Swedish job-exposure-matrix, approximately 17 900 workers were estimated to be occupationally exposed to Cr(VI) today.

CONCLUSIONS

Our study demonstrates that some workers in Sweden are exposed to high levels of the non-threshold carcinogen Cr(VI). Employers and workers seem aware of Cr(VI) exposure, but more efficient exposure control strategies are required. National strategies aligned with the European strategies are needed in order to eliminate this cause of occupational cancer.

Inflammation-related proteins in blood after dermal exposure to some common chemicals depend on the skin barrier gene filaggrin - a human experimental study

Filaggrin (FLG), a skin barrier protein, is associated with higher dermal uptake of some chemicals in carriers of loss-of-function (null) mutations. This study investigates FLG mutations and systemic effects following dermal exposure to chemicals. Individuals (n = 23 FLG null, n = 31 FLG wt) were simultaneously exposed to pyrimethanil, pyrene, oxybenzone, and nickel ions for 4 h. Pre- and post-exposure, 25-hydroxyvitamin D3 (25(OH)D3, LC-MS/MS) and 92 inflammation-related proteins (proximity-extension assay) were measured. FLG null carriers exhibited significantly higher 25(OH)D3 concentrations than wt carriers, both pre- and post-exposure. Eleven proteins differed in abundance post- vs pre-exposure among FLG null carriers, and 22 proteins among wt carriers (three proteins overlapped). Twelve proteins showed median differences (post- vs pre-exposure) between FLG null and wt carriers. Overall, FLG null carriers showed an increase, while FLG wt carriers showed a decrease in inflammation-related proteins. These findings suggest FLG-dependent differences in susceptibility to systemic effects following simultaneous dermal chemical exposure.

Cohort profile: The Swedish Tattoo and Body Modifications Cohort (TABOO)

PURPOSE

The Swedish Tattoo and Body Modifications Cohort (TABOO) cohort was established to provide an infrastructure for epidemiological studies researching the role of tattoos and other body modifications as risk factors for adverse health outcomes. It is the first population-based cohort with detailed exposure assessment of decorative, cosmetic, and medical tattoos, piercing, scarification, henna tattoos, cosmetic laser treatments, hair dyeing, and sun habits. The level of detail in the exposure assessment of tattoos allows for investigation of crude dose-response relationships.

PARTICIPANTS

The TABOO cohort includes 13 049 individuals that participated in a questionnaire survey conducted in 2021 (response rate 49%). Outcome data are retrieved from the National Patient Register, the National Prescribed Drug Register and the National Cause of Death Register. Participation in the registers is regulated by Swedish law, which eliminates the risk of loss to follow-up and associated selection bias.

FINDINGS TO DATE

The tattoo prevalence in TABOO is 21%. The cohort is currently used to clarify the incidence of acute and long-lasting health complaints after tattooing based on self-reported data. Using register-based outcome data, we are investigating the role of tattoos as a risk factor for immune-mediated disease, including hypersensitisation, foreign body reactions and autoimmune conditions.

FUTURE PLANS

The register linkage will be renewed every third year to update the outcome data, and we have ethical approval to reapproach the responders with additional questionnaires.

Nickel penetration into stratum corneum in FLG null carriers - a human experimental study

Background

The filaggrin gene (FLG) plays a role in skin diseases, with the skin barrier function being impaired in FLG null carriers. The role of FLG status in relation to nickel penetration into the skin remains unclear.

Objectives

To elucidate the association between FLG status and nickel penetration into stratum corneum (SC) in individuals without self‐reported history of nickel allergy.

Methods

Forty participants (23 FLG wt and 17 FLG null) were exposed to a nickel solution (80 μg/cm²) which was applied onto 2 × 2 cm on their left forearm. After 4 h, the area was tape‐stripped with 10 consecutive tapes. Nickel in each tape was quantified using inductively coupled plasma mass spectrometry.

Results

The average recovered nickel dose was 35%–48%. A tendency towards lower recovery was seen in FLG null carriers compared to FLG wt carriers, and lower recovery in those with history of skin and/or respiratory symptoms compared to those without such history. This was however not statistically significant.

Conclusion

FLG null carriers had less nickel recovered by tape strips compared with FLG wt carriers and, compared with individuals without a history of skin and/or respiratory symptoms, indicating higher nickel penetration into SC for FLG null carriers, but further studies are needed.

Validation of questionnaire algorithm based on repeated open application testing with the constituents of fragrance mix II: the EDEN Fragrance Study

BACKGROUND

In a European study on contact allergy in the general population, it has been hypothesized that the combination of contact allergy to a fragrance together with a history indicating dermatitis at exposure and thereafter subsequent avoidance of scented products implied a diagnosis of allergic contact dermatitis.

OBJECTIVES

The primary aim of this study was to validate this hypothesis/algorithm. The secondary aim was to investigate whether there was any association between the outcome of the recent repeated open application test (ROAT) and the patch test reactivity.

METHODS

One hundred nine subjects with and without contact allergy to fragrance mix II (FM II) were recruited. Volunteers from six European dermatology clinics participated in the study including a patch test and a ROAT.

RESULTS

Twenty-four positive ROAT reactions were noted in total including 20 of those 32 with contact allergy to FM II. None of the volunteers reacted to the vehicle (P < 0.001). More individuals with a positive algorithm had positive ROATs when compared with those with a negative algorithm. However, the difference was not statistically significant (P = 0.12). The lower the patch test concentration eliciting a positive test reaction, the more likely was a positive ROAT and the more likely that the positive ROAT appeared early during the investigative period.

CONCLUSIONS

The algorithm used in this study was not validated but it was indicated in this ROAT setup. The stronger the patch test reactivity the more likely was a positive ROAT and the more likely it was that the positive ROAT appeared early during the application period.

A comparative study between the two patch test systems Finn chambers and Finn chambers AQUA

BACKGROUND

Finn Chambers AQUA (FCA) is a development of the Finn Chambers (FC) test system in which the test chambers are mounted on a moisture-resistant adhesive patch. FCA has pre-fixed filter papers. Because the use of FCA does not require any extra taping or use of separate filter papers, a change from FC to FCA chambers may be beneficial for both patients and patch test technicians.

OBJECTIVES

To investigate whether there are any differences regarding detection of contact allergy when simultaneous patch testing is performed with FC and FCA.

MATERIALS AND METHODS

Results from 434 dermatitis patients simultaneously tested with 10 allergens in both FC and FCA were evaluated.

RESULTS

There were no significant differences regarding detection of positive reactions between the two test systems. There were significantly more doubtful reactions to methylisothiazolinone, fragrance mix I and hydroperoxides of linalool when testing with FCA. We only observed significantly more doubtful reactions in FC regarding nickel(II)sulfate. Irritant reactions to formaldehyde were also significantly more common when using FCA.

CONCLUSION

The FC and FCA had good agreement in detection of positive reactions. However, the results including doubtful and irritant reactions justify further research regarding optimization of the dose.

Filaggrin Polymorphisms and the Uptake of Chemicals through the Skin-A Human Experimental Study

BACKGROUND

The filaggrin protein is important for skin barrier structure and function. Loss-of-function (null) mutations in the filaggrin gene FLG may increase dermal absorption of chemicals.

OBJECTIVE

The objective of the study was to clarify if dermal absorption of chemicals differs depending on FLG genotype.

METHOD

We performed a quantitative real-time polymerase chain reaction (qPCR)-based genetic screen for loss-of-function mutations (FLG null) in 432 volunteers from the general population in southern Sweden and identified 28 FLG null carriers. In a dermal exposure experiment, we exposed 23 FLG null and 31 wild-type (wt) carriers to three organic compounds common in the environment: the polycyclic aromatic hydrocarbon pyrene, the pesticide pyrimethanil, and the ultraviolet-light absorber oxybenzone. We then used liquid-chromatography mass-spectrometry to measure the concentrations of these chemicals or their metabolites in the subjects' urine over 48 h following exposure. Furthermore, we used long-range PCR to measure FLG repeat copy number variants (CNV), and we performed population toxicokinetic analysis.

RESULTS

Lag times for the uptake and dermal absorption rate of the chemicals differed significantly between FLG null and wt carriers with low (20-22 repeats) and high FLG CNV (23-24 repeats). We found a dose-dependent effect on chemical absorption with increasing lag times by increasing CNV for both pyrimethanil and pyrene, and decreasing area under the urinary excretion rate curve (AUC(0-40h)) with increasing CNV for pyrimethanil. FLG null carriers excreted 18% and 110% more metabolite (estimated by AUC(0-40h)) for pyrimethanil than wt carriers with low and high CNV, respectively.

CONCLUSION

We conclude that FLG genotype influences the dermal absorption of some common chemicals. Overall, FLG null carriers were the most susceptible, with the shortest lag time and highest rate constants for skin absorption, and higher fractions of the applied dose excreted. Furthermore, our results indicate that low FLG CNV resulted in increased dermal absorption of chemicals. https://doi.org/10.1289/EHP7310.

Clinical relevance of positive patch test reactions to lanolin: A ROAT study

Background

Lanolin is often included when patch testing for common contact allergens. The clinical relevance of a positive patch test reaction to lanolin markers is, however, still a subject for debate.

Objectives

To evaluate Amerchol L101 as a marker of lanolin allergy and investigate the clinical impact of lanolin‐containing moisturizers on healthy and damaged skin using the repeated open application test (ROAT).

Methods

Twelve test subjects and 14 controls were patch tested with Amerchol L 101 and additional lanolin markers. Subsequently, a blinded ROAT was performed on the arms of the study participants for 4 weeks. Each participant applied a lanolin‐free cream base and two different lanolin‐containing test creams twice daily on one arm with intact skin and on the other arm with irritant dermatitis, induced by sodium lauryl sulfate (SLS).

Results

Eleven test subjects (92%) had positive patch test reactions to Amerchol L 101 when retested and one test subject (8%) had a doubtful reaction. None of the study participants had any skin reactions to the ROAT on intact skin and all participants healed during the ROAT on damaged skin.

Conclusions

Lanolin‐containing emollients do not cause or worsen existing dermatitis when performing ROAT in volunteers patch test positive to Amerchol L101.

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.

Patch Testing with a New Composition of Mercapto Mix: A Multi-centre Study by the Swedish Contact Dermatitis Research Group

This study investigated whether more patients with contact allergies were detected by patch testing with mercapto mix with a higher concentration of 2-mercaptobenzothiazolinone (MBT) than the commonly used mercapto mix. A total of 3,143 dermatitis patients in 5 Swedish dermatology departments were patch- tested with 3 mercapto test preparations: MBT 2.0% petrolatum (pet.); mercapto mix 2.0% pet.; and mercapto mix 3.5% pet. Positive reactions to these mercapto mixes varied between 0-0.50%, 0-0.93%, and 0-1.4%, respectively, in the 5 centres. Numerically, mercapto mix 3.5% pet. detected all positive patients and more patch-test positive patients than did the 2 other substances, but the difference was not statistically significant. The authors recommend replacing mercapto mix 2.0% pet. in the Swedish baseline series with mercapto mix 3.5% pet., since the latter also detected those patients who would have been missed because MBT 2.0% is not included in the Swedish baseline series.

Hand eczema and occupational contact allergies in healthcare workers with a focus on rubber additives

BACKGROUND

Hand eczema (HE) in healthcare workers (HCWs) is common. Besides wet work, healthcare work also implies exposure to contact allergens.

OBJECTIVES

To assess HE and contact allergy related to occupational exposures in HCWs.

METHODS

In a cross-sectional study, 311 HCWs with HE within the preceding 12 months and a control group of 114 HCWs without HE were investigated with the baseline series and a special patch test series based on substances found in the gloves, soaps, alcoholic hand disinfectants and hand creams provided at the hospitals.

RESULTS

Contact allergy to rubber additives was significantly more common in HCWs with HE (6%) than in HCWs without HE (1%, P = .02). The corresponding percentages for fragrances were 11% and 3%, respectively (P = .004). Occupational HE was found in 193 of 311 (62%) HCWs. Of these, 22 of 193 (11%) had occupational allergic contact dermatitis, including 17 with glove-related rubber contact allergy. Contact allergy to diphenylguanidine was as common as contact allergy to thiurams. Occupational contact allergy to rubber additives was significantly associated with sick-leave related to HE.

CONCLUSION

Contact allergy to rubber additives in medical gloves is the most common cause of occupational allergic contact dermatitis in HCWs. Aimed patch testing with relevant rubber additives is mandatory when HE in HCWs is investigated.

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.

The reactivity of the back revisited. Are there differences in reactivity in different parts of the back?

BACKGROUND

In the contact dermatitis literature, it is regularly stated that the patch test reactivity on various areas of the back differs, which might have a large impact on the reproducibility of patch testing.

OBJECTIVES

To investigate the reproducibility of patch testing on the upper back with regard to the left as opposed to the right side, and the medial as opposed to the lateral part of the upper back. The reproducibility over time and with regard to the reactivity pattern was also investigated.

METHODS

Thirty-one subjects with contact allergy to the metals gold (n = 19) or nickel (n = 12) were patch tested with serial dilutions, in triplicate applications, on different locations on the upper back. The Friedman test was used for statistical calculations.

RESULTS

No significant differences in the reactivity of the back were found. In all gold-allergic patients and 11 of 12 nickel-allergic patients, the allergy could be reproduced with regard to previous patch testing, but the degree of reactivity differed.

CONCLUSIONS

When a high level of standardization of the patch test technique with the same test system was used, there were no differences in patch test reactions and sites of application on the upper back.

Skincare products containing low concentrations of formaldehyde detected by the chromotropic acid method cannot be safely used in formaldehyde-allergic patients

BACKGROUND

Formaldehyde is a well-known contact sensitizer. Formaldehyde releasers are widely used preservatives in skincare products. It has been found that formaldehyde at concentrations allowed by the European Cosmetics Directive can cause allergic contact dermatitis. However, we still lack information on whether formaldehyde at low concentrations affects dermatitis in formaldehyde-allergic individuals.

OBJECTIVES

To study the effects of low concentrations of formaldehyde on irritant contact dermatitis in formaldehyde-allergic individuals.

METHODS

Fifteen formaldehyde-allergic individuals and a control group of 12 individuals without contact allergy to formaldehyde and formaldehyde releasers were included in the study. The individuals performed the repeated open application test (ROAT) during 4 weeks with four different moisturizers releasing formaldehyde in concentrations that had been determined as > 40, 20-40, 2·5-10 and 0 p.p.m. by the chromotropic acid (CA) spot test. Dimethyloldimethylhydantoin was used as a formaldehyde releaser in the moisturizers. The ROAT was performed on areas of experimentally induced sodium lauryl sulfate dermatitis. The study was double blind, controlled and randomized.

RESULTS

Nine of the 15 formaldehyde-allergic individuals had reappearance or worsening of dermatitis on the areas that were treated with moisturizers containing formaldehyde. No such reactions were observed in the control group (P < 0·001) or for the moisturizers without formaldehyde in the formaldehyde-allergic individuals (P < 0·001).

CONCLUSIONS

Our results demonstrate that the low concentrations of formaldehyde often found in skincare products by the CA method are sufficient to worsen an existing dermatitis in formaldehyde-allergic individuals.

Swedish Experiences From Patch Testing Methylisothiazolinone Separately

The preservative methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) is a well-known sensitiser and present in the Swedish baseline series since the 1980s. The proportions of MCI/MI are 3:1. MI alone has been used as a preservative since less than 10 years. This study was conducted on behalf of the Swedish Contact Dermatitis Research Group to evaluate inclusion of MI in the Swedish baseline series since the preparation of MCI/MI might fail to detect contact-allergic reactions to MI alone. Patients with suspected allergic contact dermatitis at 5 Swedish dermatology departments were consecutively patch tested with MI 2,000 ppm aq and MCI/MI 200 ppm aq. The number of cases with exclusive contact allergy to MI varied between 0.8-4.2%. In total, 1.9% reacted exclusively to MI and not to MCI/MI. Due to the considerable frequency of contact allergy to MI not traced by MCI/MI, MI 2,000 ppm aq is included in the Swedish baseline series from January 2014. This corresponds to a dose of 60 μg/cm2.

Patch testing with a textile dye mix in two concentrations - a multicentre study by the Swedish contact dermatitis research group

Disperse dyes, which are used for colouring synthetic textile fibres, are well-known contact sensitisers. To investigate the outcome of patch-testing with a textile dye mix (TDM) at 7 dermatology clinics in Sweden, a TDM tested at 2 concentrations was included into the baseline series during one year. The mix consisted of Disperse (D) Blue 35, D Yellow 3, D Orange 1 and 3, D Red 1 and 17, all 1.0%, and D Blue 106 and D Blue 124, each 0.3% in the mix 6.6% and 1.0% each in the mix 8.0%. In 2,122 tested patients, contact allergy to the TDM at the concentration 8.0% was found in 2.8% and to the TDM at 6.6% in 2.5% of the patients. The contact allergy to the TDM could explain or contribute to the dermatitis in about 35% of the patients.

CONCLUSION

contact allergy to the TDM is common and inclusion into the Swedish baseline series should be considered.

Swedish Experiences From Patch Testing Methylisothiazolinone Separately

The preservative methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) is a well-known sensitiser and present in the Swedish baseline series since the 1980s. The proportions of MCI/MI are 3:1. MI alone has been used as a preservative since less than 10 years. This study was conducted on behalf of the Swedish Contact Dermatitis Research Group to evaluate inclusion of MI in the Swedish baseline series since the preparation of MCI/MI might fail to detect contact-allergic reactions to MI alone. Patients with suspected allergic contact dermatitis at 5 Swedish dermatology departments were consecutively patch tested with MI 2,000 ppm aq and MCI/MI 200 ppm aq. The number of cases with exclusive contact allergy to MI varied between 0.8-4.2%. In total, 1.9% reacted exclusively to MI and not to MCI/MI. Due to the considerable frequency of contact allergy to MI not traced by MCI/MI, MI 2,000 ppm aq is included in the Swedish baseline series from January 2014. This corresponds to a dose of 60 μg/cm2.

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.

Patch testing with a textile dye mix in two concentrations - a multicentre study by the Swedish contact dermatitis research group

Disperse dyes, which are used for colouring synthetic textile fibres, are well-known contact sensitisers. To investigate the outcome of patch-testing with a textile dye mix (TDM) at 7 dermatology clinics in Sweden, a TDM tested at 2 concentrations was included into the baseline series during one year. The mix consisted of Disperse (D) Blue 35, D Yellow 3, D Orange 1 and 3, D Red 1 and 17, all 1.0%, and D Blue 106 and D Blue 124, each 0.3% in the mix 6.6% and 1.0% each in the mix 8.0%. In 2,122 tested patients, contact allergy to the TDM at the concentration 8.0% was found in 2.8% and to the TDM at 6.6% in 2.5% of the patients. The contact allergy to the TDM could explain or contribute to the dermatitis in about 35% of the patients.

CONCLUSION

contact allergy to the TDM is common and inclusion into the Swedish baseline series should be considered.

Patch testing with formaldehyde 2.0% in parallel with 1.0% by the Swedish contact dermatitis research group

In a multicentre study consecutively patch-tested dermatitis patients were tested simultaneously with 1.0% and 2.0% (w/v) formaldehyde in aqua applied with a micropipette (15 µl) to the filter paper disc in Finn Chambers (0.30 mg/cm(2) and 0.60 mg/cm(2), respectively). A total of 2,122 dermatitis patients were patch-tested. In all, 77 (3.6%) patients reacted positively to formaldehyde; 37 reacted only to 2.0%, 35 reacted to both concentrations and 5 patients reacted only to 1.0%. Significantly more patients were thus diagnosed with contact allergy to formaldehyde with 2.0% compared to 1.0% (p < 0.001) without causing more irritant reactions. The detected number of isolated allergic reactions to the 2 formaldehyde-releasers in the Swedish baseline series and not to formaldehyde itself raises the question whether quaternium-15 1.0% and diazolidinyl urea 2.0% should be present in the Swedish baseline series.

Patch testing with formaldehyde 2.0% in parallel with 1.0% by the Swedish contact dermatitis research group

In a multicentre study consecutively patch-tested dermatitis patients were tested simultaneously with 1.0% and 2.0% (w/v) formaldehyde in aqua applied with a micropipette (15 µl) to the filter paper disc in Finn Chambers (0.30 mg/cm(2) and 0.60 mg/cm(2), respectively). A total of 2,122 dermatitis patients were patch-tested. In all, 77 (3.6%) patients reacted positively to formaldehyde; 37 reacted only to 2.0%, 35 reacted to both concentrations and 5 patients reacted only to 1.0%. Significantly more patients were thus diagnosed with contact allergy to formaldehyde with 2.0% compared to 1.0% (p < 0.001) without causing more irritant reactions. The detected number of isolated allergic reactions to the 2 formaldehyde-releasers in the Swedish baseline series and not to formaldehyde itself raises the question whether quaternium-15 1.0% and diazolidinyl urea 2.0% should be present in the Swedish baseline series.

Usage test with palladium-coated earrings in patients with contact allergy to palladium and nickel

BACKGROUND

Since the EU Nickel Directive came into force, concern has been raised that palladium may increasingly replace nickel in alloys used in jewellery and dentistry, and that it may cause as many allergy problems as nickel.

OBJECTIVES

(i) To investigate the clinical relevance of contact allergy to palladium resulting from the wearing of palladium-coated earrings, and (ii) to evaluate the concordance in test results between palladium chloride (PdCl2 ), sodium tetrachloropalladate (Na2 PdCl4 ), and nickel(II) sulfate hexahydrate (NiSO4 .6H2 O), as well as variability in patch test reactivity.

MATERIALS/METHODS

Forty female patients with pierced earlobes and previously known contact allergy to palladium and nickel were patch tested with dilution series of nickel and palladium salts. They wore earrings covered with palladium and titanium for 9 weeks to monitor the appearance of any clinical manifestations.

RESULT/CONCLUSION

There is a low risk of eczema in palladium-allergic and nickel-allergic individuals when they wear jewellery coated with pure palladium, but further studies are needed to determine whether palladium, when present in alloys, could cause allergic reactions. PdCl2 , like NiSO4 .6H2 O, shows variability in patch test reactivity over time. Furthermore, Na2 PdCl4 seems to be a more sensitive test substance than PdCl2 for the detection of palladium allergy.

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.