Hypersensitivity angiitis caused by fumes from heat-activated photocopy paper.

A 53-year-old librarian had recurrent palpable purpura on her ankles and legs that was found to be caused by the fumes released from heat-activated photocopy paper at her place of employment. Behenic acid was identified as the responsible chemical component through a series of challenge studies that simulated her work exposure. Behenic acid, a fatty acid, is volatilized when heat-activated photocopy paper is developed. Absorption through the upper respiratory mucosa was the likely route of entry of this agent. The mechanism of this reaction is unclear. Skin biopsies, complement studies, and immune complex assays failed to confirm a type III immune response. Physicians should be aware that chemical fumes released from microfilm copying machines or other devices that use heat-activated photocopy paper may cause palpable purpura.