Methylchloroisothiazolinone and methylisothiazolinone contact allergy: A retrospective cohort study from a tertiary dermatology clinic in Turkey

Increased rates of contact allergy to selected preservatives in patients with allergic contact dermatitis in Turkey

BACKGROUND

Preservatives are a frequent cause of allergic contact dermatitis (ACD) and have caused numerous epidemics.

OBJECTIVES

The objective of this study is to determine the prevalence of preservative sensitivity, assess the change in the frequency of sensitivity, identify new preservatives with increased sensitivity rates, and evaluate the situation in Turkey by comparing our findings with current literature.

METHODS

A total of 201 patients diagnosed with ACD between 2018 and 2020, were patch tested with the European baseline series and additional seven preservative haptens. The change in the prevalence of sensitivity to each preservative hapten was investigated by comparing the data from the study conducted in our department between 2000 and 2004.

RESULTS

Results showed that 17.4% (n = 35) of the patients were positive to preservatives. Comparison with previous data from 2000 to 2004 revealed an increase in the frequency of sensitization. The most prevalent allergen was methyldibromo glutaronitrile (9.5%), followed by methylchloroisothiazolinone/methylisothiazolinone (6.5%), and methylisothiazolinone (5%).

CONCLUSION

The increase in preservative sensitivity in Turkey is the most remarkable finding. Although MDBGN was prohibited in cosmetic products, MCI/MI and MI are still widely used. Our findings suggest that awareness of preservative sensitivity should be increased and additional precautions should be taken, also in Turkey, regarding the use of preservatives.

Methyl(chloro)isothiazolinone contact allergy: a monocentric experience from Turkey

INTRODUCTION

Due to their ubiquitous use, isothiazolinones caused allergic contact dermatitis epidemics and their use was restricted by legal regulations.

OBJECTIVES

We aimed to evaluate demographic data, clinical findings, and patch test features of patients with methylisothiazolinone (MI) and/or methylchloroisothiazolinone(MCI) sensitivity in our study.

METHODS

This study is a bidirectional and cross-sectional study, between July 2020 and September 2021. A total of 616 patients, including prospective and retrospective populations, demographic data, clinical findings, and patch test results were reviewed. Patients' demographics, patch test results, allergen sources, presence of occupational contact, and the characteristics of dermatitis attacks were recorded.

RESULTS

A total of 50 patients with MI and MCI/MI sensitivity, 36 male (72%) and 14 female (28%), were included in our study. The overall prevalence of MI and MCI/MI between 2014 and 2021 was 8.4% (52/616) with two peak levels in 2015(21%) and 2021 (20%). A statistically significant relationship was found between shampoo use and facial involvement (p = 0.031), shower gel use and arm involvement (p = 0.027), wet wipe use and hand involvement (p = 0.049), detergent use and the pulps (p = 0.026) and the lateral aspects of fingers involvement (p = 0.048), water-based dye use and periungual involvement (p = 0.047).

CONCLUSION

Although legal regulations related to MI and MCI/MI cause a decrease in the frequency of their sensitivities were still common causes of allergic contact dermatitis.

Amended Safety Assessment of Methylisothiazolinone as Used in Cosmetics

The Expert Panel for Cosmetic Ingredient Safety (Panel) reassessed the safety of Methylisothiazolinone, which functions as a preservative in cosmetics. The Panel reviewed relevant animal and human data provided in this safety assessment, and data from the previously published safety assessments of Methylisothiazolinone, and concluded that Methylisothiazolinone is safe for use in rinse-off cosmetic products at concentrations up to 100 ppm (ie, 0.01%) and safe in leave-on cosmetic products when they are formulated to be nonsensitizing, which may be determined based on a quantitative risk assessment or similar methodology.

Amended Safety Assessment of Methylchloroisothiazolinone and Methylisothiazolinone as Used in Cosmetics

The Expert Panel for Cosmetic Ingredient Safety (Panel) reassessed the safety of the mixture Methylchloroisothiazolinone (MCI)/Methylisothiazolinone (MI), which functions as a preservative in cosmetic products. The Panel reviewed relevant animal and human data provided in this safety assessment, and data from the previously published safety assessment of this mixture, and concluded that MCI/MI is safe in cosmetics when formulated to be nonsensitizing, based on the results of a quantitative risk assessment or similar methodology; however, at no point should concentrations exceed 7.5 ppm in leave-on products or 15 ppm in rinse-off products.

Patch Test Results to European Baseline Series in Turkey: A Prospective and Multicenter Study

BACKGROUND

Patch testing with the European Baseline Series (EBS) is an essential diagnostic tool for the assessment of allergic contact dermatitis.

OBJECTIVE

The aims of the study were to describe the most common contact allergens identified with patch testing in Turkey and to establish the distribution of contact allergens among different regions in Turkey.

PATIENTS AND METHODS

Twelve centers consisting of tertiary health care institutions were included in the study. A total of 1169 patients were patch tested with the EBS from 2015 to 2017.

RESULTS

A total of 596 patients (51.0%) had 1 or more positive patch test reactions to the EBS. A total of 30.2% (n = 353) of those tested had clinical relevance. Contact sensitivity was more common in young patients. The most common 10 allergens were nickel sulfate (20.4%), followed by textile dye mix (8.6%), cobalt chloride (8.3%), potassium dichromate (8.0%), p-phenylenediamine base (4.5%), balsam of Peru (4.3%), methylchloroisothiazolinone/methylisothiazolinone (3.8%), thiuram mix (3.6%), fragrance mix I (3.0%), and methylisothiazolinone (2.9%).

CONCLUSIONS

This study provides a comprehensive profile of patch test results with the EBS in Turkey. An ongoing decrease in contact allergy to methylchloroisothiazolinone/methylisothiazolinone and methylisothiazolinone was observed. Textile dye mix and p-phenylenediamine are beginning to pose a new risk in Turkey.

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

BACKGROUND

Methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) and MI allergy caused a global epidemic during the period 2010 to 2015, reaching its peak in 2013/14.

OBJECTIVE

To investigate the characteristics of MCI/MI and MI allergy in Turkey over 24 years.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Patch test results of the European baseline series among 1309 patients in Turkey between 2013 and 2019

BACKGROUND

Prevalences of sensitivity to contact allergens change over time as a result of variations in allergen exposure.

OBJECTIVES

The aim of the study was to describe trends in sensitisation to allergens of the European baseline series in Turkey between 2013 and 2019.

METHODS

The patch test results of 1309 patients with suspected allergic contact dermatitis (ACD) were analysed retrospectively, and the prevalence of contact allergies to European baseline series allergens was compared with previous data (for 1998-2005).

RESULTS

A total of 534 (40.8%) patients exhibited one or more positive patch test reaction. The five most frequent allergens were nickel sulfate (19.6%), potassium dichromate (6.5%), cobalt chloride (6%), Myroxylon pereirae resin (5%), and p-phenylenediamine (PPD; 3.7%). Statistically significant increases in the prevalence of sensitisation to methylchloroisothiazolinone/methylisothiazolinone (MCI/MI; P < .001), Myroxylon pereirae resin (P < .001), PPD (P = .008), and fragrance mix I (P = .036) were observed in the 2013 to 2019 period compared with the 1998 to 2005 period. Conversely, positive reactions to neomycin sulfate (P = .029), clioquinol (P = .031), and primin (P = .001) decreased significantly.

CONCLUSION

This study provides a comprehensive profile of ACD in Turkey. The remarkable increase in the MI and MCI/MI contact allergy observed underlines the urgent need for regulatory measures to reduce exposure to MI and MCI/MI in Turkey.

Contact Allergy-Emerging Allergens and Public Health Impact

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