Aluminum in biological systems

Alkali metal hydroxides, dissolution rate effect, 521-523f Alkoxides, formation of uniform precipitates, 451-464 Aluminum, silicic acid effect on adsorption in food, 612/ 613 Aluminum in biological systems, 604, 605f, 606 Aluminum-modified silica sol, formation, 62, 63/ Aluminum-silicon interactions in biology,... 

Harris WR, Berthon G, Day JP, Exley C, Platen TP, Forbes WF, Kiss T, Orvig C and Zatta PF (1997) Speciation of aluminum in biological systems. In Yokel RA and Golub MS, ed. Research issues in aluminum toxicity, pp. 91-116. Taylor Francis, Washington, DC. 

The mechanism of action for aluminum toxicity is not known, but the element is known to compete in biological systems with cations, especially magnesium (MacDonald and Martin 1988) despite an oxidation state difference, and to bind to transferrin and citrate in the blood stream (Gannot 1986). It may also affect second messenger systems and calcium availability (Birchall and Chappell 1988), and irreversibly bind to cell nucleus components (Crapper-McLachlan 1989 Dryssen et al. 1987). Aluminum has also been shown to inhibit neuronal microtubule formation. However, much more work is needed before a mechanism can be proposed. 

Edwardson JA, Candy JM, Ince PG, et al. 1992. Aluminum accumulation, beta-amyloid deposition and neurofibrillary changes in the central nervous system. In Aluminum in biology and medicine. 

Macdonald TL, Martin RB. 1988. Aluminum ion in biological systems. Trends Biochem Sci 13 15-19. 

H. Sigel, Metal Ions in Biological Systems , Aluminum and its Role in Biology, Vol. 24, Marcel Dekker, New York, 1988. 

Inorganic ions in biological systems can be quantified by spectrophotometric methods provided they are present at suitable concentrations (of a few micrograms per milliliter or higher) and other species in the medium exhibit little or no absorption. However, many elements including aluminum, cadmium, chromium, and nickel usually cannot be determined by UV-visible spectrophotometry, because they occur at very low concentrations in biological systems. 

The assessment of internal exposure depends almost entirely on the capability of performing accurate and precise measurements of aluminum in biological materials. The analyst is faced with the problems of detecting aluminum in the ppb range and must be able to accomplish collection, storage, processing, and final analysis without outside contamination from this ubiquitous element. The abundance of aluminum in the environment complicates efforts to provide a contamination-free system [19]. 

Driscoll CT Jr, Baker JP, Bisogni JJ Jr, Schofield CL (1980) Effect of aluminium speciation on fish in dilute acidified waters. Nature 284 161-164 Edwardson JA, Candy JM, Ince PG, McArthu FK, Morris CM, Oakley AE, Taylor GA, Bjertness E (1992) Aluminum accumulation, -amyloid deposition and neurofibrillary changes in the central nervous system. In Chadwick DJ, Whelan J (eds) Aluminum in biology and medicine. Wiley, New York, pp 165-185 (Ciba foundation symposium 169)... 

Driscoll CT, Schecher WD (1988) Aluminum in the environment. In Sigel H (ed) Metal ions in biological systems. Dekker, New York, pp 59-122 Driscoll CT, van Breemen N, Mulder J (1985) Aluminum chemistry in a forested Spodosol. Soil Sci Soc Am J 49 437-443... 

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