In most people, aluminium is not as toxic as heavy metals. Aluminium is classified as a non-carcinogen by United States Department of Health and Human Services. There is little proof that normal exposure to aluminium is a risk to healthy adult. There is proof of no toxicity if it is taken in amounts not greater than 40 mg/day per kg of body mass. Most aluminium taken will leave the body in feces. Most of the small part that enters the blood, will be excreted via urine.