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Introduction Epoxy-based resin formulations are a frequent cause of allergic and irritant contact dermatitis in the construction and painting industries. Cases of epoxy resin contact dermatitis continue to persist across many sectors and are likely attributable to the growing use of epoxy products, including epoxy-based anti-corrosion coatings and inadequate skin protection. There are no published performance data against epoxy resins for garment materials and gloves to guide proper material selection in the workplace. Objectives The objective of this study was to evaluate the resistance of 5 protective garment materials against permeation and penetration by bisphenol A diglycidyl ether and its higher oligomers found commonly in epoxy-based anti-corrosion coatings. Methods Five disposable garment materials were evaluated for resistance to bisphenol A diglycidyl ether monomers and oligomers during contact with epoxy-based anti-corrosion coatings, including latex gloves, nitrile gloves, Tyvek coveralls, polypropylene/polyethylene (PP/PE) coveralls, and a cotton T-shirt. A permeation test cell system was used to evaluate each garment material against an epoxy-based zinc-rich primer and an epoxy-based intermediate coating using a realistic application method. Glass fiber filters were used to collect permeating and penetrating epoxy resin during a 120-min test period. Bisphenol A diglycidyl ether quantification was performed with high-performance liquid chromatography–electrospray ionization-tandem mass spectrometry. Paint loading, coating thickness, and homogeneity were assessed on polytetrafluoroethylene filters sprayed in series in permeation test cells. Results Latex gloves provided the least resistance to permeation by BADGE in coating formulations, with a maximum cumulative permeation over the 2-h test interval of 21.7 ng cm−2 with the primer and 513.8 ng cm−2 with the intermediate coating product. Nitrile gloves were not permeated by either coating formulation. The Tyvek coveralls provided greater protection as compared to the PP/PE coveralls. The cotton T-shirt was penetrated by bisphenol A diglycidyl ether more frequently than any of the tested garment materials and resulted in a maximum cumulative penetration of 128 ng cm−2 with the primer and 28.0 ng cm−2 with the intermediate coating. Conclusion Although all the garment materials evaluated during this study provided sufficient protection to prevent cumulative permeation in excess of the established acceptable permeation thresholds, the use of nitrile gloves and Tyvek coverall is highly recommended to minimize skin exposure to bisphenol A diglycidyl ether. We recommend cotton T-shirts to be used under Tyvek coveralls as a secondary layer of skin protection and for added comfort, but not as a primary protection layer. [ABSTRACT FROM AUTHOR]

Background Polyurethanes are a class of isocyanate-based organic coatings commonly used to control corrosion on high-value metallic structures. Despite their widespread use, dermal exposure to these isocyanate-containing coatings presents a significant occupational health risk to workers, including the development of allergic and irritant contact dermatitis and systemic sensitization. At present, little is known about the effectiveness of the protective garments commonly used to prevent dermal exposure to polyurethane coatings in construction trades. Objectives The primary objective of this study was to measure the permeation and penetration of isocyanates from polyurethane anticorrosion coatings though a selection of protective garments. In addition, a standardized spray procedure using a fixed-position spraying technique was evaluated as an option to minimize variability in coating application. Methods Five disposable garment materials were evaluated for resistance to isocyanates during this study: latex gloves (0.076 mm), nitrile gloves (0.078 mm), Tyvek coveralls (0.105 mm), polypropylene/polyethylene (PP/PE) coveralls (0.116 mm), and a cotton t-shirt (0.382 mm). A permeation test cell system was used to evaluate each garment material against two products: a polyurethane zinc-rich primer based on 4,4′-methylene diphenyl diisocyanate and an aliphatic finish coating based on prepolymers of 1,6-hexamethylene diisocyanate. Glass fiber filters pretreated with 1-(9-anthracenylmethyl)piperazine were used to collect penetrating isocyanates during the 120-min test period, which were analyzed by liquid chromatography–tandem mass spectrometry. Polytetrafluoroethylene loading filters were sprayed in series with permeation test cells and analyzed gravimetrically to assess the homogeneity of coating application. Results The latex gloves demonstrated the highest rate of isocyanate permeation of all evaluated garments during testing with both coatings (primer: 27.38 ng cm−2 min−1; finish coating: 7.39 ng cm−2 min−1). Nitrile gloves were much more resistant than latex gloves (primer: 1.89 ng cm−2 min−1; finish coating: 1.26 ng cm−2 min−1) and were not permeated by the finish coating until after 15 min. The PP/PE coverall provided the most consistent resistance to both coatings (primer: 0.08 ng cm−2 min−1; finish coating: 1.27 ng cm−2 min−1), whereas the Tyvek coverall was readily permeated by the primer (primer: 3.47 ng cm−2 min−1; finish coating: 0.87 ng cm−2 min−1). The cotton t-shirt was rapidly permeated by the primer during the first 5 min of exposure (primer: 146.65 ng cm−2 min−1; finish coating: 4.64 ng cm−2 min−1). In addition, the fixed-position spraying technique used during this study demonstrated a significant reduction in loading variability within each batch of test cells when compared to manual spray application. Conclusion Nitrile gloves demonstrated superior resistance to both isocyanate-containing coatings in comparison to latex gloves. Although both coverall materials were resistant to permeating isocyanate within the established thresholds, the PP/PE coverall provided more consistent resistance to both coatings. Owing to the cotton t-shirt's high rate of penetration with both coatings, it is recommended only as a secondary barrier. Study results showed that the use of fixed-position spray techniques provided consistent and reproducible results within each batch of test cells. Additional test design modifications are necessary to further reduce variability between batches and ensure more consistent coating thickness. [ABSTRACT FROM AUTHOR]