Airborne contact dermatitis from unexpected exposure to rosin (colophony). Rosin sources revealed with chemical analyses.

We report 3 cases of contact dermatitis in rosin-sensitive individuals caused by exposure to airborne rosin components from different sources. Case no. 1 was a female office worker with a facial dermatitis caused by rosin components which emanated from the linoleum floor covering in her office. Floor material containing wood flour and rosin was released into the air, causing a facial dermatitis in the rosin-sensitive subject. Case no. 2 involved a woman who worked in a factory producing dairy product cartons and had a dermatitis on her lower legs, lower arms and upper chest. Her dermatitis was caused by dust from the paper cartons and contact allergy to rosin components probably aggravated her dermatitis. Case no. 3 was a female office worker with a relapsing dermatitis on her eyelids. Her dermatitis was caused by a rosin-containing floor polish, which was seen as a powder on the office floor. Extracts of suspected material and products were patch tested and analysed for the presence of rosin components with HPLC and GC techniques. A discussion and recommendations on chemical analyses of rosin components follow. We conclude that a thorough investigation, including chemical analyses, can rule out non-specific diagnoses and offer a solution to the patient's skin problems.