Acetic Acid: Definition, Cleaning Uses, Safety, & More

Woman cleans a glass table with a spray
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What exactly is acetic acid? It's an acid naturally found in vinegar at the rate of about 5%. The most common ways of making it are from fermenting and oxidizing ethanol and the distillation of wood.

Synonyms

As noted in ChemIDPlus Lite, an on-line database by the U.S. National Library of Medicine, and PubChem, a database by the National Center for Biotechnology Information (NCBI), here are a few of the names acetic acid may go by:

Acetasol; Acetic acid, glacial; Aceticum acidum; Aci-Jel; Acide acetique; Acido acetico; Azijnzuur; BRN 0506007; CCRIS 5952; Caswell No. 003; EINECS 200-580-7; EPA Pesticide Chemical Code 044001; Essigsaeure; Ethanoic Acid; Ethanoic acid monomer; Ethylic acid; FEMA No. 2006; Glacial acetic acid; HSDB 40; Kyselina octova; Methanecarboxylic acid; NSC 132953; Octowy kwas; Orlex; Pyroligneous acid; UNII-Q40Q9N063P; Vinegar acid; Vosol

CAS Number: 64-19-7

Molecular Formula: C​2H4O2

Functions

Acetic acid has many functions, but it is mostly used as a chemical reagent, fungicide, herbicide, microbiocide, pH adjuster, counterirritant, and solvent in a variety of industries, including, but not limited to food, agriculture, cleaning, and cosmetics.

Cleaning Uses

Because acetic acid kills fungus and microbes, it is great for general disinfecting and combating mold and mildew. It can be found in several conventional and green cleaning products, such as mold and mildew cleaners, floor cleaners, window cleaners, surface cleaners, cleaning and dusting sprays, and roof cleaners, in the form of vinegar or as an ingredient by itself.

Other Uses

Acetic acid is used in several industries, such as the chemical (acidifier and neutralizer), agricultural (e.g., herbicide to control weeds), canning (e.g., flavorant for pickles), textile and dye (e.g., nylon production, dye catalyst), food (preservative for livestock grains and hay), cosmetics (bleaching agent), and manufacturing industries (e.g., production of lacquers).

Product Brands Containing Acetic Acid

To see if certain products contain acetic acid, try searching the U.S. Department of Health and Human Services Household Products Database, the Environmental Working Group's (EWG) Guide to Healthy Cleaning, the Good Guide, or the EWG's Skin Deep Cosmetic Database. Remember, if using the general term "acetic acid" doesn't generate a lot of results, try entering one of its synonyms.

Regulation

When acetic acid is used in personal care products, food, or drugs it is monitored by the U.S. Food and Drug Administration (FDA). For other uses, such as pesticides and cleaning products, it is monitored by the Environmental Protection Agency (EPA). The last periodic registration review of acetic acid by the EPA (Case #4001) began in 2008.

Health and Safety

According to the FDA, acetic acid and its sodium salt, sodium diacetate, are GRAS or "generally recognized as safe." The EPA notes there is no need for concern. However, citric acid does have some safety and health concerns, especially for those working with the chemical, as noted in the National Institute for Occupational Safety and Health's (NIOSH) International Chemical Safety Card (ICSC) on acetic acid.

Breathing in acetic acid can cause respiratory symptoms, such as coughing, difficulty breathing, and sore throat as well as nervous system issues, such as headache and dizziness. Contact with the eyes can result in burns, vision loss, pain, and redness, and skin contact can cause pain, redness, burns, and blisters. Also, ingesting citric acid may result in a sore throat, burning sensation, abdominal pain. vomiting, shock, or collapse. Due to these concerns, NIOSH suggests preventive measures for those working with acetic acid such as protecting the skin and eyes and providing appropriate ventilation and breathing protection.

Environmental Effects

According to the EPA, acetic acid is a chemical compound naturally present in all living organisms. It is also biodegradable and readily breaks down into carbon dioxide and water. However, in the 2008 "Acetic Acid and Salts Final Work Plan (FWP) for Registration Review" by the EPA, the EPA noted that an ecological risk assessment is still needed, including its effect on endangered species, when used as a weed controller.