Editing Zinc (section)

==Precautions==
{{main|Zinc toxicity}}

===Toxicity===
Although zinc is an essential requirement for good health, excess zinc can be harmful. Excessive absorption of zinc suppresses copper and iron absorption.<ref name="Fosmire1990" /> The free zinc ion in solution is highly toxic to plants, invertebrates, and even vertebrate fish.<ref>{{cite journal|journal=Contaminant Hazard Reviews |date=1993 |issue=10 |title=Zinc Hazard to Fish, Wildlife, and Invertebrates: A Synoptic Review |last=Eisler |first=Ronald |page=5 |publisher=U.S. Department of the Interior, Fish and Wildlife Service |location=Laurel, Maryland |bibcode=1993usgs.rept....5E |url=https://pubs.er.usgs.gov/publication/5200116 |url-status=live |archive-url=https://web.archive.org/web/20120306032807/http://www.pwrc.usgs.gov/infobase/eisler/chr_26_zinc.pdf |archive-date=March 6, 2012 }}</ref> The Free Ion Activity Model is well-established in the literature, and shows that just [[mole (unit)|micromolar]] amounts of the free ion kills some organisms. A recent example showed 6 micromolar killing 93% of all ''[[Daphnia]]'' in water.<ref>{{cite journal|title=Mechanisms of chronic waterborne Zn toxicity in Daphnia magna|first1=Brita T. A.|last1=Muyssen|last2=De Schamphelaere|first2=Karel A. C.|last3=Janssen|first3=Colin R.|journal=Aquatic Toxicology|volume=77|issue=4|date=2006|pmid=16472524|doi=10.1016/j.aquatox.2006.01.006|pages=393–401|bibcode=2006AqTox..77..393M }}</ref>

The free zinc ion is a powerful [[Lewis acid]] up to the point of being [[corrosive]]. Stomach acid contains [[hydrochloric acid]], in which metallic zinc dissolves readily to give corrosive zinc chloride. Swallowing a post-1982 American one [[Cent (United States coin)|cent]] piece (97.5% zinc) can cause damage to the stomach lining through the high solubility of the zinc ion in the acidic stomach.<ref>{{cite journal|title=Chronic Ingestion of a Zinc-Based Penny|first=Dawn N.|last=Bothwell|author2=Mair, Eric A. |author3=Cable, Benjamin B. |journal=Pediatrics|volume=111|date=2003|doi=10.1542/peds.111.3.689|pmid=12612262|issue=3|pages=689–91}}</ref>

Evidence shows that people taking 100–300&nbsp;mg of zinc daily may suffer induced [[copper deficiency]]. A 2007 trial observed that elderly men taking 80&nbsp;mg daily were hospitalized for urinary complications more often than those taking a placebo.<ref>{{cite journal|author=Johnson AR|author2=Munoz A|author3=Gottlieb JL|author4=Jarrard DF|title=High dose zinc increases hospital admissions due to genitourinary complications|journal=J. Urol.|volume=177|date=2007|pmid=17222649|doi=10.1016/j.juro.2006.09.047|issue=2|pages=639–43}}</ref> Levels of 100–300&nbsp;mg may interfere with the use of copper and iron or adversely affect cholesterol.<ref name="Fosmire1990">{{cite journal|journal=American Journal of Clinical Nutrition|volume=51|date=1990|title=Zinc toxicity|first=G. J.|last=Fosmire|pmid=2407097|issue=2|pages=225–7|doi=10.1093/ajcn/51.2.225}}</ref> Zinc in excess of 500&nbsp;ppm in soil interferes with the plant absorption of other essential metals, such as iron and manganese.<ref name="Emsley2001p504" /> A condition called the [[zinc shakes]] or "zinc chills" can be induced by inhalation of zinc fumes while [[brazing]] or welding galvanized materials.<ref name="CRCp4-42" /> Zinc is a common ingredient of [[denture]] cream which may contain between 17 and 38&nbsp;mg of zinc per gram. Disability and even deaths from excessive use of these products have been claimed.<ref>{{Cite news |url=http://www.tampabay.com/news/health/lawsuits-blame-denture-adhesives-for-neurological-damage/1073320 |title=Lawsuits blame denture adhesives for neurological damage (Denture adhesives cited in lawsuits) |newspaper=[[Tampa Bay Times|St. Petersburg Times]] |author=Richard Martin |date=February 15, 2010 |access-date=December 31, 2022 |archive-url=https://web.archive.org/web/20121011122902/https://www.tampabay.com/news/health/lawsuits-blame-denture-adhesives-for-neurological-damage/1073320/ |archive-date=October 11, 2012 |url-status=dead}}</ref>

The U.S. [[Food and Drug Administration]] (FDA) states that zinc damages nerve receptors in the nose, causing [[anosmia]]. Reports of anosmia were also observed in the 1930s when zinc preparations were used in a failed attempt to prevent [[polio]] infections.<ref>{{Cite book|url=https://books.google.com/books?id=n24Pju7kHIYC&pg=PA142|page=142|title=Conquest of viral diseases: a topical review of drugs and vaccines|author=Oxford, J. S.|author2=Öberg, Bo|publisher=Elsevier|date=1985|isbn=978-0-444-80566-9}}</ref> On June 16, 2009, the FDA ordered removal of zinc-based intranasal cold products from store shelves. The FDA said the loss of smell can be life-threatening because people with impaired smell cannot detect leaking gas or smoke, and cannot tell if food has spoiled before they eat it.<ref name="LAT">{{cite news|url=https://www.latimes.com/archives/la-xpm-2009-jun-17-sci-zicam17-story.html|title=FDA says Zicam nasal products harm sense of smell|newspaper=Los Angeles Times|date=June 17, 2009|url-status=live|archive-url=https://web.archive.org/web/20120621011505/http://articles.latimes.com/2009/jun/17/science/sci-zicam17|archive-date=June 21, 2012}}</ref>

Recent research suggests that the topical antimicrobial zinc pyrithione is a potent [[heat shock]] response inducer that may impair genomic integrity with induction of [[Poly ADP ribose polymerase|PARP]]-dependent energy crisis in cultured human [[keratinocyte]]s and [[melanocyte]]s.<ref>{{cite journal |author=Lamore SD |author2=Cabello CM |author3=Wondrak GT |title=The topical antimicrobial zinc pyrithione is a heat shock response inducer that causes DNA damage and PARP-dependent energy crisis in human skin cells |journal=Cell Stress & Chaperones |volume=15 |issue=3 |pages=309–22 |date=2010 |pmid=19809895 |doi=10.1007/s12192-009-0145-6 |pmc=2866994 }}</ref>

===Poisoning===
In 1982, the [[United States Mint|US Mint]] began minting [[Cent (United States coin)|pennies]] coated in copper but containing primarily zinc. Zinc pennies pose a risk of zinc toxicosis, which can be fatal. One reported case of chronic ingestion of 425 pennies (over 1&nbsp;kg of zinc) resulted in death due to gastrointestinal bacterial and fungal [[sepsis]]. Another patient who ingested 12&nbsp;grams of zinc showed only [[lethargy]] and [[ataxia]] (gross lack of coordination of muscle movements).<ref>{{cite journal
|title=Zinc|first=Donald G.|last=Barceloux|journal=Clinical Toxicology|author2=Barceloux, Donald |volume=37
|issue=2|pages=279–292|date=1999|doi =10.1081/CLT-100102426|pmid=10382562}}</ref> Several other cases have been reported of humans suffering zinc intoxication by the ingestion of zinc coins.<ref>{{cite journal|title=Zinc Toxicity Following Massive Coin Ingestion|journal=American Journal of Forensic Medicine and Pathology|volume=18|issue=2|pages=148–153|date=1997|last=Bennett|first=Daniel R. M. D.|author2=Baird, Curtis J. M.D. |author3=Chan, Kwok-Ming |author4=Crookes, Peter F. |author5=Bremner, Cedric G. |author6=Gottlieb, Michael M. |author7= Naritoku, Wesley Y. M.D. |doi=10.1097/00000433-199706000-00008|pmid=9185931}}</ref><ref>{{cite journal|journal=Radiology|volume=158|page=512|date=1986|title=Coin ingestion: unusual appearance of the penny in a child|first=S. K.|last=Fernbach|author2=Tucker G. F. |pmid=3941880|issue=2|doi=10.1148/radiology.158.2.3941880}}</ref>

Pennies and other small coins are sometimes ingested by dogs, requiring veterinary removal of the foreign objects. The zinc content of some coins can cause zinc toxicity, commonly fatal in dogs through severe [[hemolytic anemia]] and liver or kidney damage; vomiting and diarrhea are possible symptoms.<ref>{{cite journal|title=Zinc phosphide poisoning in dogs|journal=Journal of the American Veterinary Medical Association|volume=173|page=270|date=1978|pmid=689968|issue=3|last1=Stowe|first1=C. M.|last2=Nelson|first2=R.|last3=Werdin|first3=R.|last4=Fangmann|first4=G.|last5=Fredrick|first5=P.|last6=Weaver|first6=G.|last7=Arendt|first7=T. D.}}</ref> Zinc is highly toxic in [[parrots]] and poisoning can often be fatal.<ref>{{cite journal|journal =Australian Veterinary Journal|volume=63|issue =6|page=199|title=Zinc toxicity (new wire disease) in aviary birds|first=R. L.|last=Reece|author2=Dickson, D. B. |author3=Burrowes, P. J. |doi=10.1111/j.1751-0813.1986.tb02979.x|pmid=3767804|date =1986}}</ref> The consumption of fruit juices stored in galvanized cans has resulted in mass parrot poisonings with zinc.<ref name="Emsley2001p501" />