Safety evaluation of dietary aluminum

Aluminum is a nonessential metal to which humans are frequently exposed. Al uminum in the food supply comes from natural sources, water used in food pr eparation, food ingredients, and utensils used during food preparations. Th e amount of aluminum in the diet is small, compared with the amount of alum inum in antacids and some buffered analgesics. The healthy human body has e ffective barriers (skin, lungs, gastrointestinal tract) to reduce the syste mic absorption of aluminum ingested from water, foods, drugs, and air. The small amount of aluminum (<1%) that is systemically absorbed is excreted pr incipally in the urine and, to a lesser extent, in the feces. No reports of dietary aluminum toxicity to healthy individuals exist in the literature. Aluminum can be neurotoxic, when injected directly into the brains of anima ls and when accidentally introduced into human brains (by dialysis or shrap nel), A study from Canada reports cognitive and other neurological deficits among groups of workers occupationally exposed to dust containing high lev els of aluminum. While the precise pathogenic role of aluminum in Alzheimer 's disease (AD) remains to be de fined, present data do not support a causa tive role for aluminum in AD. High intake of aluminum from antacid for gast rointestinal ailments has not been reported to cause any adverse effects an d has not been correlated with neurotoxicity or AD. Foods and food ingredie nts are generally the major dietary sources of aluminum in the United State s. Cooking in aluminum utensils often results in statistically significant, but relatively small, increases in aluminum content of food. Common alumin um-containing food ingredients are used mainly as preservatives, coloring a gents, leavening agents, anticaking agents, etc. Safety evaluation and appr oval of these ingredients by the Food and Drug Administration indicate that these aluminum-containing compounds are safe for use in foods. (C) 2001 Ac ademic Press.