Contact Allergy to Cocamide Diethanolamine and Cross-reactions

Contact Dermatitis Associated With Hair Care Products: A Retrospective Analysis of the North American Contact Dermatitis Group Data, 2001-2016

BACKGROUND

Hair care products (HCPs) may cause both allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD).

OBJECTIVES

The aims of the study were to determine the prevalence of HCP-associated ICD/ACD and to characterize relevant allergens.

METHODS

This study is a retrospective analysis of North American Contact Dermatitis Group (NACDG) patch test data, 2001-2016.

RESULTS

Of 38,775 patients tested, 3481 (9.0%) had positive patch test reactions associated with HCPs. The HCP-positive patients were significantly more likely to be female (79.9% vs 66.0%) and/or have primary sites of dermatitis on the face (32.0% vs 27.8%) or scalp (15.4% vs 2.2%) compared with the HCP-negative patients (P < 0.0001). Of 4908 HCP-associated positive patch test reactions, 86.9% (n = 4263) were due to allergens on the NACDG screening series; p-phenylenediamine (35.8%), methylisothiazolinone (9.7%), methylchloroisothiazolinone/methylisothiazolinone (8.7%), and cocamidopropyl betaine (5.9%) were the most frequent. Most reactions (87.7%, 3736/4263) were currently clinically relevant. The most common job associated with 366 occupationally related NACDG HCP-associated allergens was hairdresser/cosmetologist (71.9%). Two hundred eighty-two patients (0.7%) had ICD associated with HCPs. Shampoo/conditioners were the most frequent source of NACDG HCP-associated reactions (47.3%) and HCP-associated ICD (45.0%).

CONCLUSIONS

Of the HCP-positive patients, 18.5% had HCP reactions to allergens not on the NACDG screening series, underscoring the importance of patch testing to expanded series in patients suspected of HCP allergy.

Allergens in Medical Hand Skin Cleansers

Health care workers may be at risk of occupational allergic contact dermatitis because of their frequent exposure to medical hand skin cleansers. We identified American Contact Dermatitis Society Core 80 Allergens found in medical hand skin cleansers (waterless skin soaps, water-needed skin soaps, and skin disinfectants) in the United States and developed a list of "low-allergen" medical hand skin cleansers. Waterless skin soaps most commonly contained fragrance, tocopherol, and sodium benzoate. Top allergens in water-needed skin soaps included fragrance, chloroxylenol, propylene glycol, and cocamidopropyl betaine. The most common allergens identified in skin disinfectants were chlorhexidine, cocamide diethanolamine, and fragrance. We identified 11 waterless skin soaps that were free of American Contact Dermatitis Society Core 80 Allergens. Low-allergen products were also identified for water-needed skin soaps (2 products) and skin disinfectants (4 products). This information is accurate as of the date of publication; product availability and ingredients may change over time.

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.