Poisoning ferrous salts

The action of hydrogen peroxide upon ferrous salts is interesting in view of the possible connection between ferrous salts acting as oxygen-carriers in the blood. The decomposition of the peroxide is hindered or poisoned by the presence of arsenious oxide, hydrogen sulphide, carbon monoxide, and other well-known poisons, and the subject is worthy of careful consideration.3... 

Now, the Physicians Desk Reference classifies inorganic ferrous sulfate as being toxic, but it is the iron source most commonly added to dietary supplements. Further, it is doubtful if inorganic iron actually corrects iron-deficiency anemia, and its poisonous nature ensures diarrhea as the body tries to rid itself of the toxin. The ubiquitous use of ferrous sulfate and other ferrous salts in multivitamins and enriched flour remains unfathomable, except maybe that this is an easy and profitable way to get rid of the stuff, a by-product from, say, sulfuric add manufacture based on iron sulfide. 

Although iron is not an environmental poison, accidental intoxication with ferrous salts used to treat iron deficiency is a frequently encountered source of poisoning in young children, iron is discussed further in Chapter 53. 

The crystals of potassium ferrocyanide are tough and difficult to powder. They are non-poisonous, but act as an aperient. When the dry anhydrous salt is heated to incipient fusion in a vacuum no gas is evolved, potassium cyanide and ferrous potassium ferrocyanide being produced —5... 

High doses of iron salts by mouth can cause severe gastrointestinal irritation and even necrosis of the mucous membrane. Autopsy shows severe damage to brain and liver. Iron poisoning is particularly dangerous in children. Sustained-release forms are safer in homes where heedless parents live with small children. Ferrous sulphate is the most toxic. 

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