An Unusual Case: Burn Following an Accidental Exposure to Methylchloroisothiazolinone/Methylisothiazolinone

Abstract

The isothiazolinone mixture 5-chloro-2-methyl-4-isothiazolin-3-one and 2-methyl-4-isothiazolin-3-one (MCI/MI), the active ingredients of biocides, is a well-known contact sensitizer. 2,3 The main sensitizing ingredient is 5-chloro-2-methyl-4-isothiazolin-3-one. 4 Laboratory studies have shown the sensitizing potential of MCI/MI to be dose-dependent. 5 MCI/MI is used in both industrial and cosmetic applications (Table 1). It is used extensively in cosmetic products in low concentrations. 6 MCI/MI-containing biocide products are manufactured by several different companies and sold under various trade names. Industrial uses of MCI/MI include mildewcides for leather and fabric, preservatives for metal-working fluids, emulsion polymers, and latex paints. 7-9 In industrial applications, allergic contact dermatitis reactions to MCI/MI are almost exclusively due to mishandling of concentrated MCI/MI solutions, and skin exposure to high concentrations may cause severe chemical burns. 6 Occupational allergic contact dermatitis is an inflammatory skin condition resulting from cutaneous contact with materials found in the workplace. 10,11 Allergic contact dermatitis (ACD), a common disorder caused by exposure to a contact allergen, is characterized acutely by erythematous macules and papules, edema, vesicles, or bullae and chronically by lichenification or scaling. 12 ACD begins with a sensitization phase, in which molecules pass through the stratum corneum and are processed by Langerhans cells in the epidermis. Antigen-coupled Langerhans cells then leave the epidermis and migrate to the regional lymph nodes via the afferent lymphatics, where they present the antigen to naive CD4 ϩ T cells. The responding T cells are stimulated via a complex immunologic process to proliferate into memory and effector T cells, which are capable of inducing ACD after repeated exposure to the allergen. The elicitation of ACD typically occurs within 48 to 96 hours after rechallenge of sensitized individuals. 13 Because the effects of MCI/MI are dose-dependent, exposure to low concentrations-as in cosmeticsresults in ACD. Exposure to high concentrations of MCI/MI-as in industrial products-results in burns and subsequent ACD. 5, 6 We report a case involving a worker who had a full-thickness skin burn after accidental exposure to concentrated solutions of MCI/MI, which also caused ACD. CASE REPORTA 24-year-old male textile factory worker accidentally spilled a small amount of concentrated MCI/MI over the pants of his left leg. The exposed area included a small region of the left posterior leg. The patient was not wearing special protective clothes and thus was directly exposed to the MCI/MI on his working pants.Immediately after the accident, the patient's clothes were removed but irrigation was not done at the factory. He presented at the nearest hospital, complaining about a red patch with mild pain and itching. According to the epicrisis sent from that hospital, two separate pruritic erythematous plaques (1.5 ϫ 1.5 cm and 1 ϫ 1 cm) were seen. Af...

Isothiazolinones in commercial products at Danish workplaces

“…Exposure to high concentrations of isothiazolinones (Table ) can cause chemical burns followed by contact sensitization resulting from a single exposure . Further accidental exposure to such high concentrations may lead to generalized dermatitis accompanied by systemic contact dermatitis and subjective symptoms .…”

Airborne‐induced lymphomatoid contact dermatitis caused by methylisothiazolinone

“…Skin exposure to high concentrations of both MCI/MI and MI can cause severe chemical burns , which may be followed by primary sensitization . Contact allergy to MI usually presents as eczematous lesions, very often on the face, with frequent involvement of the eyelids, and is often accompanied by complaints of burning and severe swelling, a mixed eczematous–urticarial skin eruption , or on the hands, where it can present as chronic eczema.…”

Ex vivo human skin permeation of methylchloroisothiazolinone (MCI) and methylisothiazolinone (MI)

“…(2015)). Although no clear thresholds are defined, skin effects are dose-dependent where low concentrations can result in ACD and high concentrations can induce severe burns as well as sensitization (Bayraktar and Ozcan 2007;Cleenewerck 2008). In the early 2000s, MCI was recognized as an extreme skin sensitizer, while MI was considered as a weak sensitizer.…”