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Corrosion of aluminum cans/cookwares leading to leaching and health problems

What kind of corrosion aluminum in canned food undergoes to consequently cause leaching of aluminum? Electrochemical corrosion perhaps? I'm a graduate student at University of Toronto taking a course on corrosion. Most literature refers to health problems related to leaching of aluminum but not that much related to the mechanism of corrosion that aluminum cans undergo.

Eilyn Rodriguez
University of Toronto - Toronto, Ontario, Canada
2003

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There are numerous standard texts on the corrosion of aluminium and probably one of the best is Shrier, so I suggest you consult that for details. As you will be aware, aluminium is protected by a tenacious oxide layer that prevents it from reacting as its position in the electrochemical series would predict. Once this layer is damaged, the exposed metal can react very quickly and even violently. However, the oxide layer is self sealing. Aluminium can undergo numerous types of corrosion, most of which are electrochemically based. These include filiform, pitting, intercrystalline and general dissolution. There is also a lot of mythology associated with ingestion of aluminium - a few years ago it was suggested the metal could promote Alzheimer's Disease, but that work has been discredited due to a mistake in the analyses. I would suggest you treat with caution any second hand information about adverse health effects.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2003