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Name: Lisa
Status: student
Grade: 6-8
Location: PA
Date: July 2008

Can the element iron be dangerous if combined with certain elements?


The short answer to your question is YES. Iron can be dangerous. Most of the danger comes from how the iron compound is stored and used.

One of the most common iron compounds is rust --iron oxide. Iron atoms can combine with oxygen atoms to make two different compounds. One is FeO, the other is Fe2O3. In FeO, one iron atom combines with one oxygen atom. In Fe2O3, two iron atoms combine with 3 atoms of oxygen. If you store rust in a closed bottle, its not dangerous.

However, if you were to step on a rusty nail with your bare foot, you would beat risk for coming down with a very serious (maybe fatal) disease called lockjaw.

Rusty iron nails and other rusty objects serve a useful purpose. When steel mill make iron and steel from iron ore, they include some rusty iron objects in the mixture.

Warren Young Rusty objects, particularly found on the ground, may harbor bacteria such as tetanus. The rust itself is not harmful, but the environment it produces might be.

--Nathan A. Unterman

Iron can react with carbon monoxide (CO) to form Fe(CO)5, and Fe(CO)4. Without doing a literature search on the specific toxicity of these compounds, it is not possible to say. But I would not be surprised if these are hazardous.

Vince Calder

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