FACTORS RELATED TO THE DEVELOPMENT OF SENSITIZATION TO GREEN COFFEE AND CASTOR BEAN ALLERGENS AMONG COFFEE WORKERS

Background Occupational allergic respiratory symptoms in coffee worker s have been frequently reported, but the ultimate cause of sensitizati on is still debated, castor bean being considered besides green coffee beans. Atopy and cigarette smoking have been suggested as promoting f actors of sensitization for several occupational allergens. Objective This study was carried out to assess the prevalence of allergic respir atory symptoms and of sensitization to both green coffee beans and cas tor bean in the whole workforce of a coffee manufacturing plant. Furth ermore we wanted to ascertain both the presence of castor bean antigen s in the settled dust of the green coffee beans warehouse and the poss ible crossreactivity between the two beans. Meanwhile, the effect of s moking and atopy was considered. Method Two-hundred and eleven workers were examined. A questionnaire on oculorhinitis and asthma was admini stered and skin-prick tests for green coffee beans, castor bean and 15 common inhalant allergens were carried out. Isoelectric focusing, iso electric focusing immunoblot and radioallergosorbent assay (RAST) inhi bition were performed on samples of settled environmental dust from th e green coffee area, as well as on castor bean and green coffee beans. Results Ten per cent of the workers complained of oculorhinitis alone and 16% of asthma (nearly always associated with oculorhinitis). The overall prevalence of skin-sensitization was: 15% for green coffee bea ns, 22% for castor bean, 22% for common allergens. Evidence of sensiti zation to occupational allergens was more common in smokers, with a mo re than twofold increase in relative risk. The strong association betw een skin positivity to common and occupational allergens suggests that atopy acts as an enhancing host factor towards occupational sensitiza tion. The analysis of the dust confirmed the presence of castor bean a ntigens. Conclusion Our findings indicate that castor bean is the majo r cause of occupational sensitization among coffee workers, whereas sm oking and atopy act as enhancing factors.