Prevalence of skin sensitization and dermatitis among epoxy-exposed workers in the wind turbine industry

New causes of occupational allergic contact dermatitis

PURPOSE OF REVIEW

Occupational allergic contact dermatitis (OACD) is an important work-related skin disease. Information about the causative agents comes from many sources, including patch test databases, registries, case series and case reports. This review summarizes new information about common causative allergens and diagnosis.

RECENT FINDINGS

Common causes of OACD include rubber components, epoxies and preservatives. New exposure sources for these allergens continue to be described. Often these exposure sources are related to the changing world around us, such as allergens related to smartphones and technology, and personal protective equipment-related exposures during the COVID-19 pandemic. New allergens are also being described, some of which are related to known allergens (e.g. a new epoxy or acrylate component).Accurate diagnosis is critical to effective management of OACD, which may include removing the worker from exposure to the causative allergen. Safety data sheets may not contain complete information and patch testing with specialized series of allergens and workplace materials may be necessary.

SUMMARY

This review provides current evidence about causes of OACD and important aspects of diagnosis. This is important for clinical practice to ensure cases of OACD are not missed.

Occupational exposure to epoxy components and risk of dermatitis: A registry-based follow-up study of the wind turbine industry

BACKGROUND

Allergic contact allergy and dermatitis are frequently reported among epoxy-exposed workers.

OBJECTIVES

To determine the risk of dermatitis associated with epoxy exposure.

METHODS

We followed 825 epoxy-exposed and 1091 non-exposed blue-collar workers, and 493 white-collar workers of a Danish wind turbine blade factory during 2017-2022 with linked data from national health registers on diagnoses, patch testing, or fillings of prescriptions for topical corticosteroids. Incidence rate ratios of dermatitis or a first-time topical corticosteroid prescription were estimated with Poisson regression using non-exposed blue-collar workers as reference. We similarly estimated incidence rate ratios for the duration of epoxy exposure and current epoxy exposure.

RESULTS

Epoxy-exposed blue-collar workers showed a dermatitis incidence rate of 2.1 per 100 000 person days, a two-fold increased risk of dermatitis and a 20% increased risk of filling a prescription for topical corticosteroids. Incidence rate ratios were higher during early exposure and declined with further exposure for both outcomes. White-collar workers had generally lower risks.

CONCLUSION

We observed an increased risk of dermatitis following epoxy exposure confirming previous case reports and cross-sectional studies emphasizing the need for intensified focus on preventive efforts for this group of workers.

Three Cases of Occupational Allergic Contact Dermatitis Where Causative Agents Were Identified Using Patch Test Panel S

Identifying the causative substances of occupational contact dermatitis is challenging because of several chemicals and materials in the workplace that can cause contact dermatitis. We experienced three cases of intractable eczema identified as work-related contact dermatitis by Patch Test Panel S, which helped identify the possible substances. We experienced three cases of occupational allergic contact dermatitis, and their causative agents were identified by Patch Test Panel S. Although there are some limitations, Patch Test Panel S might be useful to determine the substrates to cause allergic contact dermatitis in occupational scenarios.

Nature-Derived Epoxy Resin Monomers with Reduced Sensitizing Capacity─Isosorbide-Based Bis-Epoxides

Epoxy resin systems (ERSs) are a class of thermosetting resins that become thermostable and insoluble polymers upon curing. They are widely used as components of protective surfaces, adhesives, and paints and in the manufacturing of composites in the plastics industry. The diglycidyl ether of bisphenol A (DGEBA) is used in 75-90% of ERSs and is thus by far the most used epoxy resin monomer (ERM). Unfortunately, DGEBA is a strong skin sensitizer and it is one of the most common causes of occupational contact dermatitis. Furthermore, DGEBA is synthesized from bisphenol A (BPA), which is a petroleum-derived chemical with endocrine-disruptive properties. In this work, we have used isosorbide, a renewable and nontoxic sugar-based material, as an alternative to BPA in the design of ERMs. Three different bis-epoxide isosorbide derivatives were synthesized: the diglycidyl ether of isosorbide (1) and two novel isosorbide-based bis-epoxides containing either a benzoic ester (2) or a benzyl ether linkage (3). Assessment of the in vivo sensitizing potency of the isosorbide bis-epoxides in the murine local lymph node assay (LLNA) showed that all three compounds were significantly less sensitizing than DGEBA, especially 2 which was nonsensitizing up to 25% w/v. The peptide reactivity showed the same order of reactivity as the LLNA, i.e., 2 being the least reactive, followed by 3 and then 1, which displayed similar peptide reactivity as DGEBA. Skin permeation of 2 and 3 was compared to DGEBA using ex vivo pig skin and static Franz cells. The preliminary investigations of the technical properties of the polymers formed from 1-3 were promising. Although further investigations of the technical properties are needed, all isosorbide bis-epoxides have the potential to be less sensitizing renewable replacements of DGEBA, especially 2 that had the lowest sensitizing potency in vivo as well as the lowest peptide reactivity.