Editing Copper (section)

===Toxicity===
{{Main|Copper toxicity}}

Gram quantities of various copper salts have been taken in suicide attempts and produced acute copper toxicity in humans, possibly due to redox cycling and the generation of [[reactive oxygen species]] that damage [[DNA]].<ref>{{cite journal|last1=Li|first1=Yunbo|last2=Trush|first2=Michael|last3=Yager|first3=James|title=DNA damage caused by reactive oxygen species originating from a copper-dependent oxidation of the 2-hydroxy catechol of estradiol|journal=Carcinogenesis|date=1994|volume=15|issue=7|pages=1421–1427|doi=10.1093/carcin/15.7.1421|pmid=8033320}}</ref><ref>{{cite journal|last1=Gordon|first1=Starkebaum|last2=John|first2=M. Harlan|title=Endothelial cell injury due to copper-catalyzed hydrogen peroxide generation from homocysteine|pmc=424498|pmid=3514679|doi=10.1172/JCI112442|volume=77|issue=4|date=April 1986|journal=J. Clin. Invest.|pages=1370–6}}</ref> Corresponding amounts of copper salts (30&nbsp;mg/kg) are toxic in animals.<ref>{{cite web|title = Pesticide Information Profile for Copper Sulfate|url = http://pmep.cce.cornell.edu/profiles/extoxnet/carbaryl-dicrotophos/copper-sulfate-ext.html|publisher = Cornell University|access-date=10 July 2008}}</ref> A minimum dietary value for healthy growth in rabbits has been reported to be at least 3&nbsp;[[Parts per million|ppm]] in the diet.<ref>{{cite journal|author=Hunt, Charles E.|author2=William W. Carlton|name-list-style=amp |pmid=5841854 |date=1965|title=Cardiovascular Lesions Associated with Experimental Copper Deficiency in the Rabbit|journal=Journal of Nutrition |volume=87|pages=385–394|issue=4|doi=10.1093/jn/87.4.385}}</ref> However, higher concentrations of copper (100&nbsp;ppm, 200&nbsp;ppm, or 500&nbsp;ppm) in the diet of rabbits may favorably influence [[Feed conversion ratio|feed conversion efficiency]], growth rates, and carcass dressing percentages.<ref>{{cite journal|url=http://riunet.upv.es/handle/10251/10503?locale-attribute=en|author=Ayyat M.S.|author2=Marai I.F.M.|author3=Alazab A.M. |date=1995|title=Copper-Protein Nutrition of New Zealand White Rabbits under Egyptian Conditions|journal= World Rabbit Science |volume=3|issue=3 |pages=113–118|doi=10.4995/wrs.1995.249|doi-access=free|hdl=10251/10503|hdl-access=free}}</ref>

Chronic copper toxicity does not normally occur in humans because of transport systems that regulate absorption and excretion. Autosomal recessive mutations in copper transport proteins can disable these systems, leading to [[Wilson's disease]] with copper accumulation and [[cirrhosis]] of the liver in persons who have inherited two defective genes.<ref name="copper.org" />

Elevated copper levels have also been linked to worsening symptoms of [[Alzheimer's disease]].<ref>{{cite journal | author = Brewer GJ | title = Copper excess, zinc deficiency, and cognition loss in Alzheimer's disease | journal = BioFactors | volume = 38 | issue = 2 | pages = 107–113 | date = March 2012 | pmid = 22438177 | doi = 10.1002/biof.1005 | s2cid = 16989047 | type = Review| hdl = 2027.42/90519 | hdl-access = free }}</ref><ref>{{cite web|title=Copper: Alzheimer's Disease|url=http://examine.com/supplements/Copper#summary9-0|publisher=[[Examine.com]]|access-date=21 June 2015}}</ref>