Zinc toxicity

Zinc toxicity is a medical condition involving an overdose of zinc, which can cause a wide range of symptoms, including nausea, diarrhea, and even more severe effects such as damage to the pancreas and disturbances in the body's iron balance. Zinc is an essential trace element necessary for the activity of over 300 enzymes and plays a vital role in immune function, protein synthesis, wound healing, DNA synthesis, and cell division. However, when ingested in excessive amounts, zinc can become toxic.

Causes

Zinc toxicity can occur from the ingestion of large quantities of zinc, which can be found in dietary supplements, denture creams, and some industrial products. It is also possible to develop zinc toxicity from inhaling zinc fumes during welding or galvanizing processes. The body has a limited capacity for excreting excess zinc, so the metal can accumulate in the body to toxic levels if too much is consumed.

Symptoms

Symptoms of zinc toxicity include, but are not limited to:

• Nausea and vomiting
• Loss of appetite
• Stomach cramps
• Diarrhea
• Headaches
• Disruption of the body's copper and iron balance, leading to anemia and neutropenia
• Lowered immune function
• Changes in cholesterol levels

In severe cases, zinc toxicity can lead to:

• Pancreatitis
• Kidney damage
• Interference with the absorption of other essential minerals, such as copper and iron

Diagnosis

Diagnosis of zinc toxicity involves a thorough medical history, including any exposure to sources of zinc, and blood tests to measure zinc levels. Normal plasma zinc concentrations range from 0.66 to 1.10 µg/mL. Levels significantly above this range may indicate zinc toxicity.

Treatment

Treatment for zinc toxicity focuses on removing the source of excess zinc and supportive care to manage symptoms. In cases of acute zinc ingestion, gastric lavage or induced vomiting may be considered. Chelation therapy, using agents such as EDTA (ethylene diamine tetraacetic acid), may be used in severe cases to help remove zinc from the body. Supplementation with copper may also be necessary to correct the copper deficiency that can result from excessive zinc intake.

Prevention

Preventing zinc toxicity involves awareness of the potential sources of zinc and adhering to recommended dietary allowances (RDA) for zinc intake. The RDA for zinc varies by age, sex, and life stage, but for most adults, it is 8 mg per day for women and 11 mg per day for men. People should be cautious when taking zinc supplements and should not exceed the recommended doses.

See Also

• Mineral toxicity
• Heavy metal poisoning
• Dietary mineral
• Trace element deficiency