Tetrachlorophthalic anhydride asthma: evidence for specific IgE antibody

Abstract
The cases of 7 women with asthma induced by occupational exposure to an acid anhydride, tetrachlorophthalic anhydride (TCPA), an epoxy resin hardening agent, are described. Inhalation tests with TCPA at atmospheric concentrations of < 1/10 of a manufacturer''s recommended exposure limit provoked asthmatic reactions in the 4 women tested. None had evidence of pretest bronchial hyperreactivity. Immediate skin prick test reactions were elicited in the 7 subjects by a conjugate of TCPA with human serum albumin (TCPA-HSA) but not in others tested. Specific IgE antibody levels to TCPA-HSA, measured by radioallergosorbent test scores, were significantly elevated in the 7, but not in TCPA-exposed and unexposed comparison groups. Occupational asthma caused by TCPA may be an allergic reaction mediated by specific IgE antibody.