Organic Dusts, Sulfur Dioxide, and the Respiratory Tract of Swine

Abstract

Six piglets were continuously exposed to corn dust, corn dust and sulfur dioxide, or corn starch and SO₂. There were no clinical or pathological changes in the piglets exposed to corn dust alone. When combined with SO₂, both corn dust and com starch produced lesions similar to those observed earlier with SO₂ alone. Clinical changes included ocular and nasal irritation with increased salivation and central nervous system depression. Histologically, alterations in the epithelium of the turbinates and trachea included loss of cilia, disappearance of goblet cells, alteration of cell type, and metaplasia. There was a loss of cilia from epithelium of larger bronchi following exposure to corn starch and SO₂. There were no changes in the respiratory area of the lung which were attributable to exposure to dust or SO₂.