A prospective study of the relationship between exposure and specific antibodies in workers exposed to organic acid anhydrides.

ABSTRACT

BACKGROUND: The exposure-response relationships for the induction of specific IgE and IgG were evaluated in a prospective study of workers exposed to organic acid anhydrides (OAAs). Special attention was paid to the modifying effects of atopy and smoking. METHODS: The subjects were 163 previously unexposed persons exposed to epoxy resins with hexahydro-, methylhexahydro-, and methyltetrahydrophthalic anhydride as curing agents. The levels of OAAs in air and of specific IgE and IgG in serum were recurrently monitored. The mean observation time was 32 (1-105) months. RESULTS: The mean combined OAA exposure of the subjects was 15.4 (< 1-189) microg/m3. Positive specific IgE was demonstrated by 21 (13%) subjects with a mean induction time of 8.8 (1-35) months. The incidence of sensitization was 4.1 cases/1000 months at risk. The relative risk (OR) for atopics was 5.4 (1.9-15.3; 95% CI). An exposure-response relationship was demonstrated by an increasing risk of sensitization with increasing exposure. CONCLUSION: An association between exposure and atopy, respectively, and the induction of specific antibodies against OAAs were observed. The risk for atopics was comparable with the risk for the subjects in the most exposed group.