Changes

==Toxicity==

==Toxicity==

===Dog:===   

===Dog:===   

There is little information on the toxic effects of excess iron in foods, however there are several reports of the adverse effects of iron when administered directly to dogs. D’Arcy and Howard<ref name="D'Arcy">D’Arcy, PF, Howard, EM (1962). “The acute toxicity of ferrous salts administered to dogs by mouth”. J. Pathol. Bacteriol. 83:65-72.</ref> found that a dose of ferrous sulphate supplying only 12 mg iron per kg bodyweight (BW) resulted in mild gastrointestinal damage. A higher dose of 600 mg iron per kg BW was fatal. Doses of ferrous sulphate as low as 200 mg iron per kg BW administered directly to the [[Jejunum - Anatomy & Physiology|jejunum]] were fatal within 6 hours<ref>Bronson, WR, Sisson, TRC (1960). “Studies on acute iron poisoning”. Amer.  J. Dis. Children 99:18-26.</ref> and ferrous sulphate supplying 250 mg iron per kg BW was fatal within 5 to 7 hours when administered by stomach tube<ref>Reissman, E, Coleman, T (1955). “Acute intestinal iron intoxication. II. Metabolic, respiratory and circulatory effects of absorbed iron salts”. Blood 46:46-51.</ref>. In contrast, ferrous carbonate did not produce any effects at 1.5 g iron per kg BW but did at 3 g iron per kg BW. Ferric oxide fed to dogs for 18 months at a dietary content of 1% produced no adverse effects<ref name="D'Arcy"/>. These variations in toxic effects are further examples of the differences in bio-availability of iron salts.

There is little information on the toxic effects of excess iron in foods, however there are several reports of the adverse effects of iron when administered directly to dogs. D’Arcy and Howard<ref name="D'Arcy">D’Arcy, PF, Howard, EM (1962). “The acute toxicity of ferrous salts administered to dogs by mouth”. J. Pathol. Bacteriol. 83:65-72.</ref> found that a dose of ferrous sulphate supplying only 12 mg iron per kg bodyweight (BW) resulted in mild gastrointestinal damage. A higher dose of 600 mg iron per kg BW was fatal. Doses of ferrous sulphate as low as 200 mg iron per kg BW administered directly to the [[Jejunum - Anatomy & Physiology|jejunum]] were fatal within 6 hours<ref>Bronson, WR, Sisson, TRC (1960). “Studies on acute iron poisoning”. Amer.  J. Dis. Children 99:18-26.</ref> and ferrous sulphate supplying 250 mg iron per kg BW was fatal within 5 to 7 hours when administered by stomach tube<ref>Reissman, E, Coleman, T (1955). “Acute intestinal iron intoxication. II. Metabolic, respiratory and circulatory effects of absorbed iron salts”. Blood 46:46-51.</ref>. In contrast, ferrous carbonate did not produce any effects at 1.5 g iron per kg BW but did at 3 g iron per kg BW. Ferric oxide fed to dogs for 18 months at a dietary content of 1% produced no adverse effects<ref name="D'Arcy"/>. These variations in toxic effects are further examples of the differences in [[Nutrition Glossary#Bioavailability|bio-availability]] of iron salts.

 

===Cat:===

===Cat:===

As with dogs, the reports of adverse effects of iron are limited to studies of the administration of acute doses. Hoppe et al<ref>Hoppe, J, Marcelli, G, Tainter,M (1955a). “An experimental study of the toxicity of ferrous gluconate”. Am. J. Med. Sci. 230:491-498.</ref> found that acute oral doses of ferrous sulphate or gluconate equivalent to 16 to 128 mg iron per kg BW resulted in [[Vomiting|vomiting]] within one hour of administration. The same researchers found that the median lethal dose of ferrous sulphate heptahydrate in cats was greater than 500 mg iron per kg BW<ref>Hoppe, J, Marcelli, G, Tainter,M (1955b). “Progress of medical science therapeutics: A review of the toxicity of iron compounds”. Am. J. Med. Sci. 230:558-571.</ref>. In relation to the degree of toxicity, these results are broadly in line with those from the dog studies.

As with dogs, the reports of adverse effects of iron are limited to studies of the administration of acute doses. Hoppe et al<ref>Hoppe, J, Marcelli, G, Tainter,M (1955a). “An experimental study of the toxicity of ferrous gluconate”. Am. J. Med. Sci. 230:491-498.</ref> found that acute oral doses of ferrous sulphate or gluconate equivalent to 16 to 128 mg iron per kg BW resulted in [[Vomiting|vomiting]] within one hour of administration. The same researchers found that the median lethal dose of ferrous sulphate heptahydrate in cats was greater than 500 mg iron per kg BW<ref>Hoppe, J, Marcelli, G, Tainter,M (1955b). “Progress of medical science therapeutics: A review of the toxicity of iron compounds”. Am. J. Med. Sci. 230:558-571.</ref>. In relation to the degree of toxicity, these results are broadly in line with those from the dog studies.