What chemical element causes garlic breath?

Exceeding the Tolerable Upper Intake Level of 400 micrograms per day can lead to selenosis. Signs and symptoms of selenosis include a garlic odor on the breath, gastrointestinal disorders, hair loss, sloughing of nails, fatigue, irritability, and neurological damage. Extreme cases of selenosis can exhibit cirrhosis of the liver, pulmonary edema, or death.