Correlation between different measures of exposure in a cohort of bakery workers and flour millers.
Nieuwenhuijsen-MJ; Lowson-D; Venables-KM; Newman Taylor-AJ
Ann Occup Hyg 1995 Jun; 39(3):291-298
A longitudinal cohort study of workers in bakeries and flour mills was performed to assess the correlation between different measures of exposure. Three large British bakeries (200 to 450 employees each), three flour mills (60 to 200 employees each), and a flour packing station (30 employees) were surveyed. After exclusion, 265 workers were divided into exposure groups, and particle exposure was monitored using personal samplers. The four measures of exposure intensity were estimates of average full time dust, average full time flour aeroallergen, task dust and task flour aeroallergen. Exposure duration was determined using work history questionnaires, and cumulative exposure was estimated by the product of average full time exposure estimates and duration of exposure. Descriptive statistics and correlation analysis were performed. No correlation was found between exposure duration and the measured intensity of exposure. There was good correlation between average dust and average allergen levels, and between peak dust and peak allergen levels. The percentage of workers that changed category depended on which measure of exposure was examined, and this was reflected in the degree of correlation. Only a few workers changed category between peak allergen and peak dust categories. More than 50% changed category between exposure duration and the intensity measures of exposure. The higher the correlation coefficient between the measures of exposure, the fewer workers changed category. The authors state that this information is important for an enhanced understanding of exposure response relationships for workers in bakeries and flour mills.
Epidemiology; Bakery-workers; Occupational-exposure; Allergens; Exposure-levels; Questionnaires; Dust-particles; Quantitative-analysis
Annals of Occupational Hygiene
University of California - Davis