Zinc has low human toxicity by the oral route, but high levels can cause gastrointestinal distress. An acute zinc toxicity (such as from 4 g of zinc gluconate, which provides 570 mg of elemental zinc) produces some of the following symptoms: metallic taste, headache, weak heart beat, nausea, vomiting, epigastric pain, abdominal cramps and bloody diarrhea.
Tachycardia, hemolytic anemia, pancreatitis, renal damage and death have been reported on this occasion.
Long term oral intakes of zinc at levels of 18,5 to 25 mg/day can interfere with copper absorption and intakes 10 to 30 items the RDA can impair immune responses and decrease serum high density lipoprotein.
The most common sources of zinc poisoning in human are metal fumes, and illness arising the ingestion of acidic foods prepared in zinc galvanized containers. The inhalation of zinc phosphide or phosphine gas also results in acute toxicity.
Toxicity of zinc
