Occupational asthma in fruit salad processing

Background: Three subjects employed in the preparation of fruit for fruit salads reported work-related respiratory symptoms. Their work entailed removing the peel from citrus fruits, primarily oranges, following soaking of the fruits in a bath of enzymes including fungal derived pectinase and glucanase. Objectives: To investigate the respiratory symptoms reported by these workers and determine their causes. Methods The three workers were investigated by a respiratory physician, including spirometry and serial peak flow measurements. Blood was taken for the measurement of IgE and IgG antibody responses against the enzyme solution. Results: Predominant symptoms in these workers were shortness of breath, chest tightness and wheezing which were all alleviated at weekends and holidays only to occur when returning to work. Serial peak flow measurements showed a clear work-related pattern. All three had strong IgE responses to the enzyme solution used at the workplace and showed distinct patterns of binding in immunoblots. All three improved immensely following withdrawal from the workplace environment. Conclusion: Enzymes appear to be widely used in the preparation of fruit and although they are used in liquid form, exposure can occur to induce immunological sensitization and asthma.