Editing Aluminium (section)

== Biology ==

[[File:Al absorption by skin.jpg|thumb|upright=1.3|Schematic of aluminium absorption by human skin.<ref name="health1">{{Cite journal | doi=10.1039/C3EM00374D| pmid=23982047| title=Human exposure to aluminium| journal=Environmental Science: Processes & Impacts| volume=15| issue=10| pages=1807–1816| year=2013| last1=Exley | first1=C.| doi-access=free}}</ref>]]

Despite its widespread occurrence in the Earth's crust, aluminium has no known function in biology.<ref name="Ullmann" /> At pH 6–9 (relevant for most natural waters), aluminium precipitates out of water as the hydroxide and is hence not available; most elements behaving this way have no biological role or are toxic.<ref name="wou">{{cite web
|url=https://www.wou.edu/las/physci/ch412/natwater.htm|website=[[Western Oregon University]]
|title=Environmental Applications. Part I. Common Forms of the Elements in Water
|publisher=Western Oregon University|access-date=30 September 2019
|archive-date=11 December 2018|archive-url=https://web.archive.org/web/20181211082553/http://www.wou.edu/las/physci/ch412/natwater.htm|url-status=live}}</ref> [[Aluminium sulfate]] has an [[Median lethal dose|LD<sub>50</sub>]] of 6207&nbsp;mg/kg (oral, mouse), which corresponds to 435 grams (about one pound) for a {{convert|70|kg|abbr=on}} mouse.

=== Toxicity ===

Aluminium is classified as a non-carcinogen by the [[United States Department of Health and Human Services]].<ref name="Piero3">{{cite journal|last=Dolara|first=Piero|date=21 July 2014|title=Occurrence, exposure, effects, recommended intake and possible dietary use of selected trace compounds (aluminium, bismuth, cobalt, gold, lithium, nickel, silver)|journal=International Journal of Food Sciences and Nutrition|volume=65|issue=8|pages=911–924|doi=10.3109/09637486.2014.937801|issn=1465-3478|pmid=25045935|s2cid=43779869}}</ref>{{efn|While aluminium per se is not carcinogenic, Söderberg aluminium production is, as is noted by the [[International Agency for Research on Cancer]],<ref name="worldcat">{{Cite book|url=https://www.worldcat.org/oclc/11527472|title=Polynuclear aromatic compounds. part 3, Industrial exposures in aluminium production, coal gasification, coke production, and iron and steel founding.|date=1984|publisher=International Agency for Research on Cancer |isbn=92-832-1534-6|oclc=11527472|pages=51–59|access-date=7 January 2021|archive-date=11 June 2021|archive-url=https://web.archive.org/web/20210611060739/https://www.worldcat.org/title/polynuclear-aromatic-compounds-part-3-industrial-exposures-in-aluminium-production-coal-gasification-coke-production-and-iron-and-steel-founding/oclc/11527472|url-status=live}}</ref> likely due to exposure to polycyclic aromatic hydrocarbons.<ref>{{Cite journal|last1=Wesdock|first1=J. C.|last2=Arnold|first2=I. M. F.|date=2014|title=Occupational and Environmental Health in the Aluminum Industry|url= |journal=Journal of Occupational and Environmental Medicine|language=en-US|volume=56|issue=5 Suppl|pages=S5–S11|doi=10.1097/JOM.0000000000000071|pmid=24806726|pmc=4131940|issn=1076-2752}}</ref>}} A review published in 1988 said that there was little evidence that normal exposure to aluminium presents a risk to healthy adult,<ref name="gitelman88">{{cite book |url=https://books.google.com/books?id=wRnOytsi8boC&pg=PA90 |title=Physiology of Aluminum in Man |archive-url=https://web.archive.org/web/20160519101650/https://books.google.com/books?id=wRnOytsi8boC&pg=PA90|archive-date=19 May 2016 |series=Aluminum and Health |publisher=CRC Press |year=1988 |isbn=0-8247-8026-4 |page=90 }}</ref> and a 2014 multi-element toxicology review was unable to find deleterious effects of aluminium consumed in amounts not greater than 40&nbsp;mg/day per kg of [[body weight|body mass]].<ref name="Piero3" /> Most aluminium consumed will leave the body in feces; most of the small part of it that enters the bloodstream, will be excreted via urine;<ref name="atsdr">{{Cite web|url=https://www.atsdr.cdc.gov/phs/phs.asp?id=1076&tid=34|title= Public Health Statement: Aluminum|website=ATSDR |language=en|access-date=18 July 2018|archive-date=12 December 2016|archive-url=https://web.archive.org/web/20161212212014/https://www.atsdr.cdc.gov/phs/phs.asp?id=1076&tid=34|url-status=live}}</ref> nevertheless some aluminium does pass the blood-brain barrier and is lodged preferentially in the brains of Alzheimer's patients.<ref name="xu92">{{cite journal |pmid=1302300|year=1992|last1=Xu|first1=N.|last2=Majidi|first2=V.|last3=Markesbery|first3=W. R.|last4=Ehmann|first4=W. D.|title=Brain aluminum in Alzheimer's disease using an improved GFAAS method|journal=Neurotoxicology|volume=13|issue=4|pages=735–743}}</ref><ref name="yumoto09">{{cite journal
|title=Demonstration of aluminum in amyloid fibers in the cores of senile plaques in the brains of patients with Alzheimer's disease|year=2009
|last1=Yumoto|first1=Sakae|last2=Kakimi|first2=Shigeo|last3=Ohsaki|first3=Akihiro|last4=Ishikawa|first4=Akira
|journal=Journal of Inorganic Biochemistry|volume=103|issue=11|pages=1579–1584|pmid=19744735|doi=10.1016/j.jinorgbio.2009.07.023}}
</ref> Evidence published in 1989 indicates that, for Alzheimer's patients, aluminium may act by [[electrostatically]] [[crosslink]]ing proteins, thus down-regulating genes in the [[superior temporal gyrus]].<ref name="mclachlan15">{{cite journal
|doi=10.1017/S0317167100029826|title=New Evidence for an Active Role of Aluminum in Alzheimer's Disease|year=1989|last1=Crapper Mclachlan|first1=D.R.|last2=Lukiw|first2=W.J.|last3=Kruck|first3=T.P.A.|journal=Canadian Journal of Neurological Sciences|volume=16|issue=4 Suppl|pages=490–497|pmid=2680008|doi-access=free}}</ref>

=== Effects ===

Aluminium, although rarely, can cause vitamin D-resistant [[osteomalacia]], [[erythropoietin]]-resistant [[microcytic anemia]], and central nervous system alterations. People with kidney insufficiency are especially at a risk.<ref name="Piero3" /> Chronic ingestion of hydrated aluminium silicates (for excess gastric acidity control) may result in aluminium binding to intestinal contents and increased elimination of other metals, such as [[iron]] or [[zinc]]; sufficiently high doses (>50 g/day) can cause anemia.<ref name="Piero3" />

[[File:Al transport across human cells.jpg|thumb|upright=1.3|There are five major aluminium forms absorbed by human body: the free solvated trivalent cation (Al<sup>3+</sup><sub>(aq)</sub>); low-molecular-weight, neutral, soluble complexes (LMW-Al<sup>0</sup><sub>(aq)</sub>); high-molecular-weight, neutral, soluble complexes (HMW-Al<sup>0</sup><sub>(aq)</sub>); low-molecular-weight, charged, soluble complexes (LMW-Al(L)<sub>n</sub><sup>+/−</sup><sub>(aq)</sub>); nano and micro-particulates (Al(L)<sub>n(s)</sub>). They are transported across cell membranes or cell epi-/[[endothelia]] through five major routes: (1) [[paracellular]]; (2) [[transcellular]]; (3) [[active transport]]; (4) channels; (5) adsorptive or receptor-mediated [[endocytosis]].<ref name="health1" />]]

During the 1988 [[Camelford water pollution incident]], people in [[Camelford]] had their drinking water contaminated with [[aluminium sulfate]] for several weeks. A final report into the incident in 2013 concluded it was unlikely that this had caused long-term health problems.<ref>{{cite web
|title=Lowermoor Water Pollution incident "unlikely" to have caused long term health effects
|publisher=Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment|date=18 April 2013
|url=https://cot.food.gov.uk/sites/default/files/cot/cotpnlwpirv2.pdf|access-date=21 December 2019|url-status=live
|archive-date=21 December 2019|archive-url=https://web.archive.org/web/20191221033817/https://cot.food.gov.uk/sites/default/files/cot/cotpnlwpirv2.pdf}}</ref>

Aluminium has been suspected of being a possible cause of [[Alzheimer's disease]],<ref>{{Cite journal|last=Tomljenovic|first=Lucija|date=21 March 2011|title=Aluminum and Alzheimer's Disease: After a Century of Controversy, Is there a Plausible Link?|url=https://www.medra.org/servlet/aliasResolver?alias=iospress&doi=10.3233/JAD-2010-101494|journal=Journal of Alzheimer's Disease|volume=23|issue=4|pages=567–598|doi=10.3233/JAD-2010-101494|pmid=21157018|access-date=11 June 2021|archive-date=11 June 2021|archive-url=https://web.archive.org/web/20210611060821/https://content.iospress.com/articles/journal-of-alzheimers-disease/jad101494|url-status=live}}</ref> but research into this for over 40 years has found, {{as of|2018|lc=yes}}, no good evidence of causal effect.<ref>{{cite web
|title=Aluminum and dementia: Is there a link?|date=24 August 2018
|publisher=Alzheimer Society Canada
|url=https://alzheimer.ca/en/Home/About-dementia/Alzheimer-s-disease/Risk-factors/Aluminum|access-date=21 December 2019|url-status=live
|archive-date=21 December 2019|archive-url=https://web.archive.org/web/20191221040250/https://alzheimer.ca/en/Home/About-dementia/Alzheimer-s-disease/Risk-factors/Aluminum}}
</ref><ref>{{Cite journal|last1=Santibáñez|first1=Miguel|last2=Bolumar|first2=Francisco|last3=García|first3=Ana M|date=2007|title=Occupational risk factors in Alzheimer's disease: a review assessing the quality of published epidemiological studies|journal=Occupational and Environmental Medicine|volume=64|issue=11|pages=723–732|doi=10.1136/oem.2006.028209|issn=1351-0711|pmc=2078415|pmid=17525096}}</ref>

Aluminium increases [[estrogen]]-related [[gene expression]] in human [[breast cancer]] cells cultured in the laboratory.<ref>{{cite journal
|title=Metalloestrogens: an emerging class of inorganic xenoestrogens with potential to add to the oestrogenic burden of the human breast|date=2006
|last1=Darbre|first1=P.D.
|journal=Journal of Applied Toxicology|volume=26|pages=191–197|pmid=16489580|issue=3|s2cid=26291680|doi=10.1002/jat.1135}}
</ref> In very high doses, aluminium is associated with altered function of the blood–brain barrier.<ref>{{cite journal
|author=Banks, W.A.|date=1989|title=Aluminum-induced neurotoxicity: alterations in membrane function at the blood–brain barrier|last2=Kastin|first2=A.J.
|journal=Neurosci Biobehav Rev|volume=13|issue=1|pages=47–53|doi=10.1016/S0149-7634(89)80051-X|pmid=2671833|s2cid=46507895}}
</ref> A small percentage of people<ref name="BinghamCohrssen2012">{{cite book
|url=https://books.google.com/books?id=1mk3lFVtBSQC&pg=PA244|title=Patty's Toxicology, 6 Volume Set|last1=Bingham|first1=Eula|last2=Cohrssen|first2=Barbara|year=2012|publisher=John Wiley & Sons|isbn=978-0-470-41081-3|page=244|access-date=23 July 2018|archive-date=20 December 2019|archive-url=https://web.archive.org/web/20191220172223/https://books.google.com/books?id=1mk3lFVtBSQC&pg=PA244|url-status=live}}</ref> have contact [[allergy|allergies]] to aluminium and experience itchy red rashes, headache, muscle pain, joint pain, poor memory, insomnia, depression, asthma, irritable bowel syndrome, or other symptoms upon contact with products containing aluminium.<ref>{{Cite news
|url=https://allergy-symptoms.org/aluminum-allergy/|title=Aluminum Allergy Symptoms and Diagnosis|date=20 September 2016|work=Allergy-symptoms.org|access-date=23 July 2018
|language=en-US|archive-date=23 July 2018|archive-url=https://web.archive.org/web/20180723152243/https://allergy-symptoms.org/aluminum-allergy/|url-status=live}}</ref>

Exposure to powdered aluminium or aluminium welding fumes can cause [[pulmonary fibrosis]].<ref>{{Cite journal|last1=al-Masalkhi|first1=A.|last2=Walton|first2=S.P.|date=1994|title=Pulmonary fibrosis and occupational exposure to aluminum|journal=The Journal of the Kentucky Medical Association|volume=92|issue=2|pages=59–61|issn=0023-0294|pmid=8163901}}</ref> Fine aluminium powder can ignite or explode, posing another workplace hazard.<ref>{{cite web|url=https://www.cdc.gov/niosh/npg/npgd0022.html|title=CDC – NIOSH Pocket Guide to Chemical Hazards – Aluminum|website=www.cdc.gov|archive-url=https://web.archive.org/web/20150530203735/http://www.cdc.gov/niosh/npg/npgd0022.html|archive-date=30 May 2015|url-status=live|access-date=11 June 2015}}</ref><ref>{{cite web|url=https://www.cdc.gov/niosh/npg/npgd0023.html|title=CDC – NIOSH Pocket Guide to Chemical Hazards – Aluminum (pyro powders and welding fumes, as Al)|website=www.cdc.gov|archive-url=https://web.archive.org/web/20150530205127/http://www.cdc.gov/niosh/npg/npgd0023.html|archive-date=30 May 2015|url-status=live|access-date=11 June 2015}}</ref>

=== Exposure routes ===

Food is the main source of aluminium. Drinking water contains more aluminium than solid food;<ref name="Piero3" /> however, aluminium in food may be absorbed more than aluminium from water.<ref name="Yokel2008">{{cite journal|author=Yokel R.A.|author2=Hicks C.L.|author3=Florence R.L.|date=2008|title=Aluminum bioavailability from basic sodium aluminum phosphate, an approved food additive emulsifying agent, incorporated in cheese|journal=[[Food and Chemical Toxicology]]|volume=46|issue=6|pages=2261–2266|doi=10.1016/j.fct.2008.03.004|pmc=2449821|pmid=18436363}}</ref> Major sources of human oral exposure to aluminium include food (due to its use in food additives, food and beverage packaging, and cooking utensils), drinking water (due to its use in municipal water treatment), and aluminium-containing medications (particularly antacid/antiulcer and buffered aspirin formulations).<ref>{{Cite report|author=[[United States Department of Health and Human Services]]|url=http://abcmt.org/tp22.pdf|title=Toxicological profile for aluminum|date=1999|access-date=3 August 2018|archive-date=9 May 2020|archive-url=https://web.archive.org/web/20200509192819/http://abcmt.org/tp22.pdf|url-status=live}}</ref> Dietary exposure in Europeans averages to 0.2–1.5&nbsp;mg/kg/week but can be as high as 2.3&nbsp;mg/kg/week.<ref name="Piero3" /> Higher exposure levels of aluminium are mostly limited to miners, aluminium production workers, and [[Kidney dialysis|dialysis]] patients.{{cn|date=March 2025}}

Consumption of [[antacid]]s, antiperspirants, [[vaccine]]s, and cosmetics provide possible routes of exposure.<ref name="ChenThyssen2018">{{cite book|url=https://books.google.com/books?id=hKlVDwAAQBAJ&pg=PA333|title=Metal Allergy: From Dermatitis to Implant and Device Failure|last1=Chen|first1=Jennifer K.|last2=Thyssen|first2=Jacob P.|publisher=Springer|year=2018|isbn=978-3-319-58503-1|page=333|access-date=23 July 2018|archive-date=26 December 2019|archive-url=https://web.archive.org/web/20191226141303/https://books.google.com/books?id=hKlVDwAAQBAJ&pg=PA333|url-status=live}}</ref> Consumption of acidic foods or liquids with aluminium enhances aluminium absorption,<ref>{{cite journal|author=Slanina, P.|last2=French|first2=W.|last3=Ekström|first3=L.G.|last4=Lööf|first4=L.|last5=Slorach|first5=S.|last6=Cedergren|first6=A.|date=1986|title=Dietary citric acid enhances absorption of aluminum in antacids|journal=Clinical Chemistry|volume=32|issue=3|pages=539–541|pmid=3948402|doi=10.1093/clinchem/32.3.539}}</ref> and [[maltol]] has been shown to increase the accumulation of aluminium in nerve and bone tissues.<ref>{{cite journal|last1=Van Ginkel|first1=M.F.|last2=Van Der Voet|first2=G.B.|last3=D'haese|first3=P.C.|last4=De Broe|first4=M.E.|last5=De Wolff|first5=F.A.|date=1993|title=Effect of citric acid and maltol on the accumulation of aluminum in rat brain and bone|journal=The Journal of Laboratory and Clinical Medicine|volume=121|issue=3|pages=453–460|pmid=8445293}}</ref>

=== Treatment ===

In case of suspected sudden intake of a large amount of aluminium, the only treatment is [[deferoxamine mesylate]] which may be given to help eliminate aluminium from the body by [[chelation therapy]].<ref name="Toxicity">{{Cite web|url=http://www.arltma.com/Articles/AlumToxDoc.htm|title=ARL: Aluminum Toxicity|website=www.arltma.com|access-date=24 July 2018|archive-date=31 August 2019|archive-url=https://web.archive.org/web/20190831154809/http://www.arltma.com/Articles/AlumToxDoc.htm|url-status=dead}}</ref><ref>[http://www.med.nyu.edu/content?ChunkIID=164929 Aluminum Toxicity] {{webarchive|url=https://web.archive.org/web/20140203055539/http://www.med.nyu.edu/content?ChunkIID=164929|date=3 February 2014}} from [[NYU Langone Medical Center]]. Last reviewed November 2012 by Igor Puzanov, MD</ref> However, this should be applied with caution as this reduces not only aluminium body levels, but also those of other metals such as copper or iron.<ref name="Toxicity" />