Working with crops and animals can lead to several disorders. Hypersensitivity pneumonitis is a rare but serious problem caused by repeated exposures to mold-contaminated grain or hay. The lung's air sacs become inflamed and may develop scar tissue.
Grain in metal bins can get moldy. Breathing dust from this grain can lead to fevers, chills, and a flu-like illness called "organic dust toxic syndrome." Farmers also are more likely to report a cough and chest tightness.
"We think about 30% of farmers who grow crops in this way have had that at some point," Von Essen says. Workers in hog and chicken barns sometimes get an asthma-like syndrome.