Allergic contact dermatitis to the elastic bands of an N95 mask

Case report Introduction: In the wake of the COVID-19 pandemic, occupational contact dermatitis related to the use of personal protective equipment (PPE) has become increasingly prevalent. While most cases are irritant in nature, allergic contact dermatitis (ACD) remains an important cause of occupational dermatitis. We report a case of ACD to rubber accelerators in the elastic bands of an N95 mask. Informed consent was obtained from the patient for this report. Case Report: A 27-year-old healthcare worker presented with a progressive pruritic eruption over her face and neck, 1 week after she began wearing N95 masks at work. She had only worn disposable surgical masks. She had no medical history apart from hand dermatitis, which was well controlled with topical medications. Examination revealed linear eczematous plaques along her lateral cheeks and posterior neck, corresponding to contact areas between the mask bands and her skin. Patch tests revealed a positive reaction to several rubber accelerators, including Thimerosal, 2-Mercaptobenzothiazole (MBT), and Methylisothiazolinone. We performed another patch test to several N95 mask straps, to which the patient developed an eczematous reaction to the elastic bands of 2 N95 mask types with elastic bands. Clarification with the manufacturer confirmed the use of rubber accelerators similar in properties to MBT in the production of these masks. A diagnosis of allergic contact dermatitis to rubber accelerator was made. The patient's dermatitis resolved with topical corticosteroids and the avoidance of N95 masks with elastic bands. Discussion and Conclusion(s): The use of facial PPE such as masks is a recognised cause of occupational dermatitis among healthcare workers. A variety of dermatoses are associated with the use of facial PPE, with contact dermatitis being the most common. However, while the majority of contact dermatitis are irritant in nature, ACD remains an important and preventable cause of occupational dermatitis. Commonly implicated allergens associated with mask use include preservatives and adhesives used in their production, as well as metals in the nose clip. Although less common, mask elastic bands have also been reported to be a potential source of ACD, with rubber accelerators being identified as potential allergens. However, there is often a lack of declaration of such chemicals used in the production of PPE. Given the need for continued use in the occupational setting, early identification and avoidance of allergens are key. Failure to do so may result in the progression of skin lesions, ultimately affecting the patients' quality of life and work performance. With the ubiquitous use of masks in the current climate, we wish to highlight the need for greater awareness of rubber accelerators as potential allergens, and their presence in the elastic bands of frequently used PPE.

Allergic contact dermatitis caused by elastic bands from FFP2 mask

Background: A 29-year-old woman, with personal history of atopy, presented with face and neck dermatitis lasting 6 months. During the past year, she worked as a nurse in a COVID-19-dedicated ward. The dermatitis had developed since she started using FFP2 masks. She referred using three FFP2 masks, with similar symptoms: 3 M© 9320+, Halyard© Fluidshield N95 and PM 2.5©. She also mentioned history of contact-hypersensitivity reactions to metals, green clothes and leather shoes for several years. Physical examination exhibited erythematous plaques distributed along the contact area of the elastic bands of the FFP2 masks. Patch tests revealed delayed hypersensitivity to the elastic bands 3 M© 9320+ and PM 2.5© (++), mercapto mix (++), 2-mercaptobenzothiazole (MBT) (++), 2-(4-morpholinylmercapto)benzothiazol (MOR) (++), N-cyclohexyl-2-benzothiazolesulfenamide (++), textile dye mix Mx-30 (++), disperse yellow 3 (++), disperse blue 106 (+), potassium dichromate (+), cobalt dichloride (+) and nickel sulfate hexahydrate (+). A latex skin prick test was negative. Allergic contact dermatitis (ACD) caused by elastic bands of FFP2 masks (3 M© 9320+ and PM 2.5 ©) was diagnosed. She was prescribed methylprednisolone aceponate 0.1% cream bid during five days and masks were changed to a type with cotton cloth bands, with resolution of the complaints. ACD to FFP2 masks components in health care workers can be severe, given the prolonged and continuous contact with the source of allergens. The rubber additives thiurams and dithiocarbamates are the main allergen groups involved in ACD to rubber bands in FFP2 masks. This seems to be the first report caused by mercaptobenzothiazole.

Modern Approaches to the Synthesis and Transformations of Practically Valuable Benzothiazole Derivatives.

The review is devoted to modern trends in the chemistry of 2-amino and 2-mercapto substituted benzothiazoles covering the literature since 2015. The reviewed heterocycles belong to biologically active and industrially demanded compounds. Newly developed synthesis methods can be divided into conventional multistep processes and one-pot, atom economy procedures, realized using green chemistry principles and simple reagents. The easy functionalization of the 2-NH2 and 2-SH groups and the benzene ring of the benzothiazole moiety allows considering them as highly reactive building blocks for organic and organoelement synthesis, including the synthesis of pharmacologically active heterocycles. The review provides a summary of findings, which may be useful for developing new drugs and materials and new synthetic approaches and patterns of reactivity.