UC Irvine

This review assembles evidence derived from both epidemiological and laboratory studies that suggest exposure to aluminum salts may be more hazardous than generally recognized. The overview describes how available levels of environmental aluminum may be increasing, and it is suggested that this can have adverse health consequences. High levels of aluminum compounds are already recognized as being neurologically harmful, but there is growing evidence that low levels of aluminum can also have adverse consequences. The mechanism, by which aluminum salts can promote the onset and development of neurodegenerative diseases, is likely by way of acceleration of intrinsic undesirable events that are already taking place in the aging brain. The most deleterious of these is the gradual increase of inflammatory events with age that not associated with any exogenous provocative stimuli. The superfluous inflammation is harmful to cerebral function, and its intensity is further augmented in neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. Aluminum at low levels, paralleling those found in some residential drinking water supplies, leads to cerebral inflammation in experimental animals. Thus, the variable incidence of Alzheimer's disease and other age-related neurodegenerative in different populations may be impacted by the extent of aluminum ingestion. This subtle effect may be important in that it can be a major factor in overall incidence of diseases related to neurosenescence.