Bioinorganic Chemistry of Aluminium & Silicon
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Human Exposure to Aluminium
We are carrying out research to understand how humans might be exposed to aluminium and how such exposures might be estimated and any effects revealed.
- Aluminium in Tobacco and Cannabis
- Aluminium and Multiple Sclerosis
- Aluminium and Alzheimer's Disease
- Aluminium and Camelford
- Aluminium and Heroin Abuse
- Aluminium and Breast Cancer
- Aluminium in Suncare Products
A biochemical tree of life for the natural selection of aluminium. Concomitant with the emergence of higher forms of life are significant concentrations of environmental silicic acid and commensurate insignificant concentrations of biologically reactive aluminium. Silicic acid limits the biological availability of aluminium, and it is unable to compete with Mg(II), Ca(II), Fe(II/III) for binding by phosphate, carboxylate and hydroxyl functional groups. Aluminium is excluded from inorganic biochemistry. Subsequently over tens of millions of years and, recently concomitant with the activities of modern human beings, an increase in the concentration of biologically reactive aluminium occurs. This increase, coincident now and in the foreseeable future with evolutionarily-driven lower levels of environmental silicic acid, displaces essential metals from biomolecules which are integral to vital biochemical processes. Aluminium is now competitive and has become an active participant in biochemical evolution. What then are the implications of such for future biochemistry? Key: Degree of shading indicates changes through evolutionary time in the environmental concentrations of biologically reactive (i) silicic acid ([Si(OH)4]B; blue) and (ii) aluminium ([Al]B; red). The extent of coloured branches and their variously-shaped leaves estimates the major metal ion competitors for Al(III) and their preferred functional groups for binding respectively. mya: million years ago. From Exley (2009).
For more information, please check out the following references:
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- Exley C (1998) Does antiperspirant use increase the risk of aluminium-related disease, including Alzheimer's disease ?Molecular Medicine Today 4, 107-109.
- Exley C (1999) A molecular mechanism of aluminium-induced Alzheimer's disease?Journal of Inorganic Biochemistry 76, 133-140.
- Exley C (Editor) (2001) Aluminium and Alzheimer’s Disease: The Science that Describes the Link. Elsevier Science, Amsterdam, The Netherlands. 441p.
- Exley C (2001) Aluminium and Alzheimer’s disease. Journal of Alzheimer’s Disease 3, 551-552.
- Exley C (2003) A biogeochemical cycle for aluminium ?Journal of Inorganic Biochemistry, 97, 1-7.
- Exley C (2004) Aluminum in antiperspirants: More than just skin deep. American Journal of Medicine 117, 969-970.
- Exley C (2004) Aluminium-containing DTP vaccines. The Lancet Infectious Diseases 4, 324.
- Exley C (2005) Comment on “The biological behaviour and bioavailability of aluminium in man” by N.D. Priest, JEM, 2004, 6, 375. Journal of Environmental Monitoring 7, 640.
- Exley C, Begum A, Woolley MP & Bloor RN (2006) Aluminium in tobacco and cannabis and smoking-related disease. American Journal of Medicine 119, 276.e9-276.ell.
- Exley C, Mamutse G, Korchazhkina O, Pye E, Strekopytov S, Polwart A & Hawkins C (2006) Elevated urinary excretion of aluminium and iron in multiple sclerosis. Multiple Sclerosis 12, 533-540.
- Exley C & Esiri M (2006) Severe cerebral congophilic angiopathy coincident with increased brain aluminium in a resident of Camelford, Cornwall, UK. Journal of Neurology Neurosurgery and Psychiatry 77, 877-879.
- Exley C (2006) Aluminium-adsorbed vaccines. The Lancet Infectious Diseases 6, 189.
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- Exley C (2007) Aluminium, tau and Alzheimer’s disease.Journal of Alzheimer’s Disease 12, 313-315
- Exley C, Ahmed U, Polwart A & Bloor RN (2007) Elevated urinary aluminium in current and past users of illicit heroin. Addiction Biology 12, 197-199.
- Exley C, Charles LM, Barr L, Martin C, Polwart A & Darbre PD (2007) Aluminium in human breast tissue. Journal of Inorganic Biochemistry 101, 1344-1346.
- Nicholson S & Exley C (2007) Aluminium: A potential pro-oxidant in sunscreens/sunblocks? Free Radical Biology and Medicine 43, 1216-1217.
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- Exley C (2009) Darwin, natural selection and the biological essentiality of aluminium and silicon. Trends in Biochemical Sciences 34, 589-593.
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- Exley C (2012) Aluminium in biological systems. Encyclopedia of Metalloproteins (Kretsinger RH, Permyakov EA, Uversky VN eds.) Springer Science (In the press).
- Exley C (2012) Elucidating aluminium’s exposome. Current Inorganic Chemistry (In the press).
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