Organic dust exposure in dairy farmers in an alpine region

Epidemological studies suggest that farmers are at an increased risk for chronic obstructive pulmonary disease because of exposure to organic dust. We assessed the proportion of farmers among patients with end stage lung disease and we measured the seasonal exposure of dairy farmers to organic dust in a rural alpine region in Switzerland.

Six dairy farms of different sizes and infrastructures were chosen for measurements of organic dust (PM10 = particles with a 50% cut-off aerodynamic diameter of 10 gm). Indoor measurements were performed during 3-5 days at each farm in late winter, summer and early winter of one year.

17 measurements of organic dust were carried out on 6 different farms. The concentrations of PM10 ranged from 109-2207 microg/m3 for daily barn activities in winter months and from 76-4862 microg/m3 for hay storage in summertime. Exposure depended on farm infrastructure and season. It was higher in smaller and older cattle buildings and during the late winter months. The farmers were exposed to the measured amount of organic dust (PM10) for 5 to 6 hours per day during the winter (approximately 900-1260 hours/year).

The study confirms a moderate to high exposure to organic dust (PM10) in these farmers, which, together with epidemiological data, suggests that such exposure over many years could be a major risk factor for the development of chronic obstructive pulmonary disease in dairy farmers.