Mold on bread can contain allergic reaction-causing spores as well as mycotoxins, dangerous compounds which can cause upset stomach or even death. Moldy bread should be carefully discarded and never eaten.
Mold growing on food or on the walls of damp houses may contain mycotoxins. Exposure to mycotoxins can cause breathing problems and fever; long-term exposure may cause chronic problems such as cancer, lupus and mental retardation.
More mild effects of eating moldy bread include upset stomach, nosebleeds, headache, diarrhea and flu-like symptoms.
Mold also can cause respiratory problems or allergic reactions if the spores are inhaled.
Mold on bread and other foods can survive in cold temperatures. It will grow roots deep into the bread, so cutting off visible mold or removing a few moldy pieces from a loaf will not protect you from toxins.
Dispose of moldy bread carefully, outside the house if possible. Wear gloves and a face mask to avoid handling or inhaling spores, disinfect areas where the mold grew and throw out any food that may have been cross-contaminated.