Aug 01, 1997
Aluminum is the most common metallic element in the earth’s crust. It is present in water and food. It does not appear to have any role in animal and human biology; it is just there. However, it can have toxic effects particularly on the brain and kidneys when present in very high doses in the blood. Aluminum is deposited in the brain and kidneys when blood levels of aluminum are very high, usually due to increased intravenous administration during a medical procedure. Aluminum toxicity occurred accidentally in the early days of renal dialysis (a technique used to cleanse the blood in cases of kidney failure); this toxicity has since been prevented. Also, a number of years ago it was suggested that aluminum played a role in Alzheimers Disease because it was often found in degenerated cells of the brain in persons with Alzheimers Disease. Subsequent studies indicated that aluminum was probably deposited in these brain cells after their death. Although not finally resolved, the danger of aluminum serving as a contributor to Alzheimers Disease has essentially been discarded.
Aluminum accumulates in the body when protective gastro-intestinal mechanisms are by-passed (e.g. the presence of aluminum in intravenous solutions), renal function is impaired and exposure is high. These conditions are sometimes present in intravenously fed premature infants.
The results of a study of aluminum toxicity in premature infants receiving intravenous solutions was recently reported. 1 Intravenous feeding solutions were provided to 227 premature infants in England; half received standard solutions commonly used in England and the USA (standard solutions generally contain low levels of aluminum); the other half received special solutions from which aluminum was removed. Brain function development was evaluated in both groups at age 18 months.
For premature infants receiving the solutions containing aluminum for 10 days or less, there were no differences between the two groups; when given for more than 10 days, there is a trend that brain function development is somewhat less in infants receiving solutions containing aluminum. However, the results are only a trend and are not considered significant.
Aluminum has been studied as a factor in a wide number of disorders; particularly of the brain. Although positive trends are found, the results so far have never been found to be scientifically significant except for large overdoses causing rapidly developing toxicity — in essence, poisoning. However, these trends are “nagging” and continue to stimulate additional studies. It is nearly impossible to avoid aluminum ingestion, but the gastro-intestinal tract handles it easily. In high risk populations (such as premature infants) who have to take intravenous solutions (nearly all of which contain small amounts of aluminum) for extended periods of time (more than 10 days), it is probably wise to look for and be careful of high levels of aluminum in the blood. But even so, a relationship to developmental brain damage such as cerebral palsy has not been found.
No — don’t throw away your aluminum pots!
1 Bishop, N.J. et al. Aluminum Neurotoxicity in Preterm Infants Receiving Intravenous Feeding Solutions. NEJM 1997; 336: 1557-1561.
© UCP Research & Educational Foundation, August 1997