Immunological status and respiratory function were studied in a group of 45 coffee workers. Skin tests with coffee allergens demonstrated the highest percentage of positive reactions to dust collected during emptying bags (4000%), followed by dust of green (12%) and then roasted coffee (8-9%). Among 34 skin-tested control workers, 14-7% had positive skin reaction to dust collected during emptying bags, but none had positive skin reaction to green or roasted coffee. Serum levels of total IgE were increased in 24-4% of coffee workers and in 5'9% of control subjects. The prevalence of all chronic respiratory symptoms was significantly higher in coffee workers than in control subjects. Coffee workers with positive skin tests to coffee allergen had a significantly higher prevalence of chronic cough (63 6%) and chronic phlegm (72-7%) than those with negative skin tests (32-4% and 23-5% respectively). There was a significant mean decrease over the Monday work shift in the maximum expiratory flow rate at 50% of vital capacity (MEF50: -7 9%) and at 25% vital capacity (MEF25: -17-8%), suggesting an obstructive effect mostly in smaller airways. Coffee workers with positive skin tests to coffee allergens had larger acute reductions in flow rates than those with negative skin tests but the difference was not statistically significant.In one of our previous epidemiological studies we have shown that exposure to green or roasted coffee is likely to contribute to the development of chronic respiratory symptoms and lung function changes in exposed workers.' Rhinitis, asthma, conjunctivitis, or dyspnoea in subjects exposed to coffee have been reported by several authors.2-3 However, there have been few studies dealing with the more detailed immunological changes related to coffee dust exposure. 6-10In the present epidemiological investigation we have studied the relationship between some immunological tests and lung function changes.
MethodsThe study was performed in 45 non-smoking female workers employed in processing roasted or green coffee. Their mean age was 31 years (range: 20 to 56 yr) with a mean duration of employment in the coffee industry of seven years (range: one to 18 yr). In addition, a group of Address for reprint requests: Dr E Zulkin, Andrija Stampar School of Public Health, Rockefellerova 4,41000 Zagreb, Yugoslavia. 9 45 non-smoking female control workers employed in the production of soft drinks was studied.
IMMUNOLOGICAL STUDIESAll coffee workers and 34 control workers were skin-tested with aqueous extracts of occupational and common allergens using the standard intradermal test. Occupational allergens were prepared from-three different types of settled dust collected on operating machines in the workroom. These included roasted coffee, green coffee, and dust collected during emptying green coffee from bags. Intradermal skin tests with these allergens were performed using a dilution of 1: 500 (0'02 ml of solution). Workers were also tested with skin-test material of house dust, bacteria, Dermatophagoi...