Methods
Ventilatory lung function and total serum IgE were measured in 104 sugar cane workers in five departments at one refinery before the harvesting season, and repeated for 77 of the workers at the end of the season. Information on the prevalence of respiratory and other symptoms was collected with a standardised questionnaire. During the harvesting season, inhalable dust, endotoxin and mould levels were measured among 74 randomly selected sugar cane workers across departments.