Wheat flour sensitisation and airways disease in urban bakers.

A total of 176 bakers and 24 subjects employed as bread slicers and wrappers were studied to examine the effect of occupational category on respiratory symptoms, ventilatory capacity, non-specific bronchial reactivity, and prick skin test responses to wheat and common allergens. Bakers had a greater prevalence of attacks of wheeze and dyspnoea and more frequently considered that work affected their chests than did slicers and wrappers. Bakers with a history of asthma with onset since starting work in a bakery had a greater prevalence of chronic cough and sputum, increased bronchial reactivity, and positive prick skin test responses to wheat and common allergens than other bakers. There was a significant association between the frequency of positive prick skin tests to wheat and common allergens, suggesting that prior atopy facilitates sensitisation to cereal antigens. The frequency of positive prick skin responses to common allergens, however, declined with increasing baking duration whereas the frequency of positive skin responses to wheat increased with increasing baking duration, suggesting that subjects who were sensitised to common allergens were leaving the industry whereas subjects who stayed in the industry increased their risk of developing sensitisation to wheat. Oven handlers had a greater prevalence of attacks of wheeze and dyspnoea and more frequently considered that work affected their chests than either dough makers or general bakers. They also had a greater prevalence of positive prick skin test responses to wheat than dough makers or general bakers. Oven handlers also had a lower mean standardised casual FEV1 than either general bakers or dough makers. Thus oven handlers appear to have a greater risk of developing respiratory allergy and airflow obstruction than bakers in other occupational categories.