Ispaghula sensitization in workers manufacturing a bulk laxative

Exposure to ispaghula dust in a pharmaceutical factory resulted in chest tightness/wheeze, nasal, and ocular or skin symptoms in 48 of 92 exposed workers. Whilst symptoms were not incapacitating in the majority (44) of these, one worker required antihistamines and three others experienced severe respiratory symptoms when exposed to the dust. These three were atopic, had a positive RAST and skin test to ispaghula; a combination unique to them. There was a significant relationship between work-related symptoms and atopic status, however, smoking did not influence symptoms, total serum IgE and specific anti-ispaghula IgE. We conclude that handling ispaghula produces an irritant effect in most exposed people, however, sensitization to the dust can occur with severe respiratory symptoms.