[Formaldehyde and phthalic anhydride asthma. Demonstration of specific IgE antibodies with RAST]

Two patients with positive formaldehyde RAST and 3 with positive phthalic anhydride RAST are described, of whom 3 presented with a typical history of occupational asthma and one had only work-related rhinitis. The fifth case with specific IgE antibodies to formaldehyde had only a domestic exposure-effect relationship; asthmatic symptoms had first started some weeks after renovation of the patient's apartment. Thus far, failing proof of specific IgE antibodies, a true allergic reaction to formaldehyde in particular has been doubted. Presenting respiratory symptoms were considered to be probably due to irritant effects. The reported cases indicate that formaldehyde and phthalic anhydride may also exert their effect through immunologic mechanisms.