The Dr Mercola website has a lot of information and you can use the search function for specific information.
I found this article there and in part reads...
Beware of Toxic Iron Supplements
For those of you struggling with the opposite issue -- iron deficiency anemia -- the best source of iron is high quality red meat, preferably grass-fed, organic. If that?s not available, or you simply prefer not to eat red meat, you can take an iron supplement instead.
But a strong word of caution is in order.
Ferrous sulfate, a form of iron found in many multivitamins, including children?s multivitamins, is a relatively toxic, inorganic metal that can lead to significant problems.
The biggest danger is acute overdose, which can be lethal. This has been known to happen when a child gets into a bottle of children?s chewable vitamins and munches them down like a tasty snack.
A safe form of supplement is carbonyl iron. To the best of our knowledge there?s never been a reported overdose of carbonyl iron, however you should still keep iron supplements away from children.
Remember, you should not take iron supplements, including carbonyl iron, if you have:
Hemachromatosis (iron overload) Hemosiderosis Hemolytic anemia (as I described in the beginning)
Lot more at: http://articles.mercola.com/sites/articles/archive/2009/07/14/Little-Known-Secrets-about-Optimal-Iron-Levels.aspx
