Formic Acid

The dangers of formic acid depend on its concentration. At higher concentrations formic acid is corrosive, has a strong smell, and produces dangerous fumes. It produces burns and blisters on the skin and injures the eyes and the mucous membranes in the mouth, throat, and respiratory system. Inhaling concentrated formic acid makes breathing difficult. Swallowing the concentrated acid causes severe ulcers (sores) to appear in the digestive tract as well as pain and nausea. Prolonged exposure to formic acid may produce liver or kidney damage.

Formic acid has low toxicity (hence its use as a food additive), with an LD50 of 1.8 g/kg (tested orally on mice). The concentrated acid is corrosive to the skin. Formic acid is readily metabolized and eliminated by the body. Nonetheless, it has specific toxic effects; the formic acid and formaldehyde produced as metabolites of methanol are responsible for the optic nerve damage, causing blindness seen in methanol poisoning. Some chronic effects of formic acid exposure have been documented. Some experiments on bacterial species have demonstrated it to be a mutagen. Chronic exposure in humans may cause kidney damage. Another possible effect of chronic exposure is development of a skin allergy that manifests upon re-exposure to the chemical. Concentrated formic acid slowly decomposes to carbon monoxide and water, leading to pressure buildup in the containing vessel. For this reason, 98% formic acid is shipped in plastic bottles with self-venting caps.

Formic acid in 85% concentration is flammable, and diluted formic acid is on the U.S. Food and Drug Administration list of food additives. The principal danger from formic acid is from skin or eye contact with the concentrated liquid or vapors. The U.S. OSHA Permissible Exposure Level (PEL) of formic acid vapor in the work environment is 5 parts per million parts of air (ppm).

Precautions:

Depending on how concentrated it is, formic acid can either be unnoticeable or very dangerous. Through the course of our typical interaction with this chemical, we are exposed only to very low concentrations. Because of this, there is very little to fear. If exposed at high concentrations, however, there are many dangerous side effects that can occur. The most dangerous aspect of the formic acid is its highly corrosive nature when in a concentrated form. Because it is so corrosive, highly concentrated amounts of formic acid can lead to serious injury if it is inhaled, swallowed or touched directly. This includes ulcers, nausea, burns, blisters and extreme discomfort around the affected area. Although it is not likely except under special situations, high concentrations of formic acid should be avoided altogether.

First Aid:

Eye Contact: Immediately flush with large amounts of water for at least 30 minutes, lifting upper and lower lids. Remove contact lenses, if worn, while flushing. Seek medical attention.
Skin Contact: Quickly remove contaminated clothing. Immediately wash contaminated skin with large amounts of soap and water. Seek medical attention.
Inhalation: Remove the person from exposure. Begin rescue breathing (using universal precautions) if breathing has stopped and CPR if heart action has stopped. Medical observation is recommended for 24 to 48 hours after overexposure, as pulmonary edema may be delayed.

Formic Acid can affect you when inhaled and may be absorbed through the skin. Formic Acid is a CORROSIVE CHEMICAL and contact can severely irritate and burn the skin and eyes with possible eye damage.Inhaling Formic Acid can irritate the nose and throat. Inhaling Formic Acid can irritate the lungs. Higher exposures may cause a build-up of fluid in the lungs (pulmonary edema), a medical emergency. Exposure to Formic Acid can cause headache, dizziness, nausea and vomiting. Exposure to high concentrations, particularly in susceptible individuals, may cause a skin allergy. Formic Acid may damage the kidneys.