Iron poisoning | |
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Synonym | iron toxicity, iron overdose |
Iron poisoning is an iron overload caused by a large excess of iron intake and usually refers to an acute overload rather than a gradual one. The term has been primarily associated with young children who consumed large quantities of iron supplement pills, which resemble sweets and are widely used, including by pregnant women; approximately 3 grams is lethal for a two-year-old. Targeted packaging restrictions in the US for supplement containers with over 250 mg elemental iron have existed since 1978, and recommendations for unit packaging have reduced the several iron poisoning fatalities per year to almost zero since 1998. No known cases of iron poisoning have been identified that are associated with iron mining.
The first indication of iron poisoning by ingestion is stomach pain, as iron is corrosive to the lining of the gastrointestinal tract, including the stomach. Nausea and vomiting are also common symptoms and bloody vomiting may occur. The pain then abates for 24 hours as the iron passes deeper into the body, resulting in metabolic acidosis, which in turn damages internal organs, particularly the brain and the liver. Iron poisoning can cause hypovolemic shock due to iron's potent ability to dilate the blood vessels. Death may occur from liver failure.
If intake of iron is for a prolonged period of time, symptoms are likely to be similar to other causes of iron overload.
In nature, iron is usually found in its oxidized form, iron (III) oxide, which is insoluble. Ferrous iron, iron (II), is soluble and its toxicity varies, largely with the integrity of the gastrointestinal lining. Iron supplements are typically used to treat anemia. Modalities include: diet, parasite control,vitamin A, riboflavin (B2),vitamin C (for absorption), folate(B9), vitamin B12 and multivitamin-multimineral supplements, with or without iron; potentially avoiding the use of iron only supplements.