Organic dust-related respiratory and eye irritation in Norwegian farmers

BACKGROUND: Information on exposure to organic dust and work-related symptoms in farmers is sparse. METHODS: An exposure study was nested in a survey of 8,482 farmers and spouses. Task-related respiratory and eye symptoms were recorded by questionnaire. Personal exposure to total dust, fungal spores, bacteria, endotoxins, and ammonia during 12 different tasks was measured in a random sample of 127 farms (288 measurements). RESULTS: The prevalence of work-related symptoms occurring "often" was 31% and "seldom" 35%. Specific tasks provoking symptoms were reported by 5-55% of the farmers. Task mean exposures ranged from 0.04 to 2 mg dust/m(3), 0.02 x 10(6) to 2 x 10(6) fungal spores/m(3), 0.2 x 10(6) to 48 x 10(6) bacteria/m(3), 0.5 x 10(3) to 28 x 10(3) endotoxin units/m(3), and 0 to 8 ppm ammonia. Task mean exposure levels were positively correlated with task-specific symptom prevalences for total dust, fungal spores, and endotoxins but not for bacteria and ammonia. CONCLUSION: Work-related symptoms are common in farmers and are associated with exposure to total dust, fungal spores, and endotoxins.