Zinc toxicity

From Infogalactic: the planetary knowledge core
Jump to: navigation, search
Zinc toxicity
Zn-TableImage.png
Classification and external resources
Specialty Lua error in Module:Wikidata at line 446: attempt to index field 'wikibase' (a nil value).
ICD-10 T56.5
ICD-9-CM 985.8
Patient UK Zinc toxicity
[[[d:Lua error in Module:Wikidata at line 863: attempt to index field 'wikibase' (a nil value).|edit on Wikidata]]]

Zinc toxicity is a medical condition involving an overdose on, or toxic overexposure to, zinc. Such toxicity levels have been seen to occur at ingestion of greater than 225 mg of zinc.[1] Excessive absorption of zinc can suppress copper and iron absorption. The free zinc ion in solution is highly toxic to bacteria, plants, invertebrates, and even vertebrate fish.[2][3][4] Zinc is an essential trace metal with very low toxicity in humans.[1][5]

Signs and symptoms

Following an oral intake of extremely high doses of zinc (where 300 mg Zn/d – 20 times the US RDA – is a "low intake" overdose[1]), nausea, vomiting, pain, cramps and diarrhea may occur.[1] There is evidence of induced copper deficiency, alterations of blood lipoprotein levels, increased levels of LDL, and decreased levels of HDL at long-term intakes of 100 mg Zn/d.[1] The USDA RDA is 15 mg Zn/d.[1]

There is also a condition called the "zinc shakes" or "zinc chills" or metal fume fever that can be induced by the inhalation of freshly formed zinc oxide formed during the welding of galvanized materials.[6]

High levels of intake by humans

Zinc has been used therapeutically at a dose of 150 mg/day for months and in some cases for years, and in one case at a dose of up to 2000 mg/day zinc for months.[7][8][9][10][11] A decrease in copper levels and hematological changes have been reported; however, those changes were completely reversed with the cessation of zinc intake.[9]

However, zinc has been used as zinc gluconate and zinc acetate lozenges for treating the common cold[12] and therefore the safety of usage at about 100 mg/day level is a relevant question. Thus, given that doses of over 150 mg/day for months to years has caused no permanent harm in many cases, a one week usage of about 100 mg/day of zinc in the form of lozenges would not be expected to cause serious or irreversible adverse health issues in most persons.

One study has shown zinc to be highly efficacious for curing warts; oral intake of zinc sulfate for two months at levels up to 600 mg/day was found to induce complete clearance of recalcitrant warts, with a success rate of 87%.[13]

Unlike iron, the elimination of zinc is concentration-dependent.[14]

See also

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Lua error in package.lua at line 80: module 'strict' not found.
  2. Lua error in package.lua at line 80: module 'strict' not found.
  3. Lua error in package.lua at line 80: module 'strict' not found.
  4. Lua error in package.lua at line 80: module 'strict' not found.
  5. Lua error in package.lua at line 80: module 'strict' not found.
  6. Lua error in package.lua at line 80: module 'strict' not found.
  7. Lua error in package.lua at line 80: module 'strict' not found.
  8. Lua error in package.lua at line 80: module 'strict' not found.
  9. 9.0 9.1 Lua error in package.lua at line 80: module 'strict' not found.
  10. Lua error in package.lua at line 80: module 'strict' not found.
  11. Lua error in package.lua at line 80: module 'strict' not found.
  12. Lua error in package.lua at line 80: module 'strict' not found.
  13. Lua error in package.lua at line 80: module 'strict' not found.
  14. Lua error in package.lua at line 80: module 'strict' not found.