Dust exposure in piggeries.

The aim of this study was to measure the total concentrations of dust in piggeries and to analyze the components of the dust. Dust samples were taken from 15 fattening pig and/or sow farms situated in southern Finland. Total concentrations of dust were measured by the gravimetric method; the organic portion of the total dust was determined by ashing, mass distribution determined by Cascade Centripeter sampler, count distribution by optical analyzer, and toxic metals of the total dust by atomic absorption spectrophotometer. The mean concentrations of total dust at stationary sampling sites were higher on fattening pig farms (9.4 +/- 1.7 mg/m3) (mean +/- SE) than on sow farms (5.2 +/- 1.2 mg/m3). The concentrations in the breathing zone were 8.6 +/- 2.7 mg/m3 and 7.9 +/- 3.2 mg/m3, respectively. The proportion of organic dust was about 90% in the dust of pig units. The mass median aerodynamic diameter of the dust particles in pig fattening units was 11 micron. Concentrations of toxic metals (nickel, cobalt, copper, zinc, chromium, cadmium) were very low.