Skin lesions due to exposure to methyl bromide

Six patients were occupationally exposed to high concentrations of methyl bromide during a fumigation procedure using adequate airway protection. Within a few hours all patients developed skin lesions, consisting of sharply demarcated erythema with multiple vesicles and large bullae. There was a striking predisposition for parts of the skin that were relatively moist or subject to mechanical pressure, such as axillae, groin, and abdomen. Microscopically, early skin lesions revealed necrosis of keratinocytes, severe edema of the upper dermis, subepidermal blistering, and diffuse infiltration of neutrophils and, to a lesser degree, eosinophils. Two patients developed an urticarial rash approximately one week after the exposure. On histologic examination, these late lesions showed combined features of a spongiotic dermatitis and urticaria. No immunopathologic manifestations were observed. In all patients, the skin returned to normal after four weeks, except for some residual hyperpigmentation. Plasma bromide levels after exposure strongly suggested percutaneous absorption of methyl bromide.