Abstract
Sera of 91 people were assayed for IgE which bound to a p-tolyl-isocyanate-human serum albumin conjugate. The sera came from 20 blood donors, 70 factory workers, and 1 casualty patient. Three factory workers had abnormally high assay values in association with active TDI disease, as indicated by asthma or measurement showing chronic airway obstruction. One factory worker had an exceptionally high assay value without clinical evidence of TDI disease. Hapten inhibition studies are reported; they indicate possible heterogeneity of the IgE detected by the assay. Brief clinical histories of some cases of TDI disease are given, suggesting that TDI disease can include susceptibility to asthma triggered by events other than TDI exposure.