Sodium Nitrite Dangers

The "CRC Handbook of Chemistry and Physics" defines sodium nitrite as a salt with the chemical formula NaNO2. It's commonly used as a preservative in foods as a strong oxidizing agent. This means that sodium nitrite helps prevent bacteria growth and colonization on foods, particularly meats. There are several health concerns associated with sodium nitrite, however.

Nitrosamine Formation

While nitrites themselves aren't carcinogens -- agents that cause cancer -- they can react with various other chemicals to produce known carcinogens, which is one of the dangers of nitrites in food. Explain Drs. Reginald Garrett and Charles Grisham in their book "Biochemistry," nitrites react strongly with nitrogen-containing molecules, including amino acids. Because proteins are made up of amino acids, and preserved meats -- protein -- often contain nitrites, nitrite-cured meat provides the perfect environment for this chemical reaction. The reaction forms carcinogenic compounds called nitrosamines that can lead to tumors.

Methemoglobinemia

Oxidizing agents do more than simply react with and inhibit growth of bacteria. In fact, strong oxidizing agents can oxidize, or steal electrons, from many different molecules in the body. One of the concerns associated with consumption of large quantities of nitrites is that they can oxidize hemoglobin -- the protein in red blood cells that carries oxygen from the lungs to the body tissues. The American Medical Association reports that consumption of large quantities of nitrites leads to formation of methemoglobin, which means oxidized hemoglobin. In the oxidized form, hemoglobin can't carry oxygen to the tissues, leading to tissue oxygen starvation.

Toxicity

In small amounts, sodium nitrite isn't toxic, though it can form compounds that are highly dangerous through chemical reactions in the body. In large quantities, however, the salt itself may be harmful, notes the "Material Safety Data Sheet" for nitrate. It irritates mucous membranes and can lead to rapid heart rate and rapid breathing, as well as seizures, coma, and death. Excess contact with skin and eyes causes redness, itching and swelling.