Urticaria isocyanates

Other skin symptoms, except contact dermatitis, have seldom been reported to be caused by isocyanates. Urticaria has been described by Schiirmann (1955) and Israeli et al. (1981). Our patient was a welder who had been welding mild steel profiles for 10 years and, occasionally, Forster Therm steel-PU profiles. The inside of the steel profile was made of PU, which was synthesized from MDI, polyol, and trichlorofluoro-methane as a blowing agent according to the information from the manufacturer, although it was evident that other substances had also been used. 

Exposure to isocyanates and auxiliary chemicals may also result in both allergic and irritant contact dermatitis, as well as urticaria (Malten 1964, 1982 Rothe 1976 Israeli et al. 1981 Fisher 1986 Kanerva et al. 1989, 1991 Estlander et al. 1992). 

Polyurethane, polyester and phenol-formaldehyde resins may occur in model making, but sensitisation at the work place is rare. Allergy caused by benzoyl peroxide (hardener in polystyrol-systems) and by amine-based hardeners (model making, repair) are a little more common. Polyisocyanates and isocyanates can also be part of glues utilised in assembly for the connection of parts (interior trim) of the doors for example. If the ventilation is not sufficient, even airborne contact allergy (contact urticaria) is conceivable. Colophony allergy will be associated with solder-... 

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