Allergic contact dermatitis due to a polyurethane elastomer (spandex) is reported. The dermatitis presents a characteristic distribution over the back, corresponding to the spandex-containing portions of bras. In each case the patients also have positive closed patch-test reactions to the rubber accelerator mercaptobenzothiazole. It is postulated that this chemical radical or a closely related chemical structure is used in the manufacture of spandex.
PORTER PS, SOMMER RG. Contact Dermatitis Due to Spandex. Arch Dermatol. 1967;95(1):43-44. doi:10.1001/archderm.1967.01600310049009