Aluminum

Aluminum is ubiquitous in the environment. Its proportion of the Earth's crust is about 8%. Aluminum can be absorbed from the gastrointestinal tract and from the lungs. Excretion is mainly through the kidneys, probably as aluminum citrate. Aluminum is a well-known neurotoxicant. Significant accumulation in the human body has been related to the presence of aluminum in dialysis fluids and the concomitant intake of aluminum-containing drugs by those with significant renal impairment and to occupational exposure in some industrial settings. Accumulation in patients with renal impairment has resulted in dialysis encephalopathy that was often fatal; this problem is now well recognized and usually avoided. Neurotoxic effects have been observed in welders with aluminum urine concentrations around 100 mu g/L. The upper reference limit among nonexposed individuals is 16 mu g/L urine. There is no consensus on whether human studies provide sufficient evidence for an association between aluminum and Alzheimer disease.Occupational exposure to aluminum powder has resulted in pulmonary fibrosis.Asthma has been associated with the inhalation of aluminum sulfate, aluminum fluoride, and potassium aluminum tetrafluoride, and exposure to the complex environment in potrooms during electrolytic aluminum production.Cancer and ischemic heart disease have been observed among aluminum production workers. However, it is unlikely that aluminum is the cause of these diseases.Reproductive and developmental toxicity are presented in Chapter 20.Recent reviews on aluminum were written by Krewski et al. (2007), Riihimaki and Aitio (2012), Willhite et al. (2012), DECOS (2010), and NEG (2011).