Acetic Acid: Everything You Need to Know

In July 2021, a La Porte chemical spill at the LyondellBasell plant caused the death of two contractors and injured dozens more. Our chemical spill lawyers filed suit against LyondellBasell and other companies for their role in causing the plant leak and harming over 50 employees and contractors.

The main chemical released by a malfunctioning pressurized cap was glacial acetic acid, a common solvent used in the production of cosmetics, polyesters, and other everyday materials. The LyondellBasell plant in La Porte is the world’s third-largest producer of glacial acetic acid, so it’s a key part of the company’s business.

But what is acetic acid? And how can something so dangerous be so common?

What Is Acetic Acid?

Acetic acid—aka ethanoic acid or “vinegar acid”—lends vinegar its acrid smell. It’s a natural byproduct of fermentation, and vinegar itself is a solution of 4–6% acetic acid and water. However, industrial processes often use what’s called “glacial acetic acid,” which is acetic acid with no traces of water.

Why It’s Called “Glacial” Acetic Acid

Water-free acetic acid has a high melting point, so it’ll form ice-like crystals at regular temperatures (i.e. under 62 degrees).

Industrial Uses of Acetic Acid

Part of what makes acetic acid so useful for manufacturing is its role as the key ingredient in multiple types of acetates, which is a salt made from combining acetic acid with a base chemical.

All of the following require acetic acid:

• Metal acetates used in printing
• Vinyl acetates used to produce plastics
• Cellulose acetates used for photographic production and textiles
• Organic esters (a group of acetates) used for solvents

Consequently, acetic acid is a key part of numerous industrial processes, including the processes that produce synthetic fiber and fabric. It’s used in the production of dyes, insecticides, rubber, antibiotics, vitamins, and many other things.

One of the most common uses of acetic acid in consumer goods is manufacturing cosmetics; it’s used to control the pH level of personal care products. Chemical peels use different kinds of acid to create a limited sort of skin burn intended to improve the health and appearance of your face. Acetic acid is one of the industrial chemicals that manufacturers would use to ensure your mask is not excessively acidic and safe to use.

However, forms of acetic acid in vinegar, food preservatives, or cosmetics are 90+% diluted with water. Glacial acetic acid is 100% concentrated and thus far more dangerous. Most consumers will never encounter acetic acid in this form, but it’s fairly common in industrial settings.

The Effects of Acetic Acid Exposure

Workers can be exposed to acetic acid in a number of ways: inhalation, eye or skin contact, and swallowed. Repeated exposure in small amounts has been known to cause the skin to harden, thicken, and form painful cracks, according to studies done on industrial workers. It can also erode the front teeth and chronically inflame the body’s airways.

However, acute acetic acid exposure has a far more drastic effect. The July 2021 incident led to the spillage of 100,000 pounds of acetic acid, so workers were exposed to vastly higher amounts of it than the human body is able to handle.

Sudden acetic acid exposure can lead to the following, among other symptoms:

• Damage to nose, throat, and lung lining
• Loss of sight due to eye damage
• Fluid buildup in the lungs (pulmonary edema)
• Severe burns on the skin

Sufficient buildup of lung fluid can be fatal, as can severe chemical burns.

Impact of Acetic Acid Spills on Communities

Acetic acid, given its wide range of industrial uses, is a compound that might be more common in our environments than we realize. Acetic acid is soluble in water and easily becomes vapor, allowing it to disperse rapidly into the environment. Despite this, there are minimal environmental guidelines for managing acetic acid, primarily because it typically degrades into harmless substances before it can cause long-term environmental damage.

Certain industries report emissions of acetic acid as part of their operations. These include paper mills and paper production facilities, meat production plants, textile production, chemical manufacturing, and metal ore mining. Consequently, if you live in proximity to any of these industrial plants, you might be exposed to higher-than-average concentrations of acetic acid in the air.

Living with someone who works with glacial acetic acid can also increase your risk of exposure. Glacial acetic acid is a concentrated form of the substance and can cling to clothing, posing an exposure risk over time. However, acetic acid has a distinctive and detectable odor, which can serve as an early warning sign of its presence.

Despite these risks, it’s important to note that most communities are more likely to encounter hazards from chronic exposure to low levels of acetic acid, rather than acute exposure from significant spills or leaks. It’s always advisable to be aware of the potential risks, especially if you live near industrial facilities that use or produce this common yet potentially hazardous compound.

Treatment of Acetic Acid Injuries

When it comes to treatment, immediate decontamination is the first step. This includes removing any contaminated clothing and flushing the affected skin or eyes with water. Inhalation victims might need supplemental oxygen or other respiratory support, but they must be moved to fresh air as soon as possible. Ingestion of acetic acid is a medical emergency, and treatment usually involves supportive care and damage control. If a worker has swallowed any amount of concentrated acetic acid, they need to immediately drink as much water as possible to dilute it.

Preventative measures involve the use of appropriate personal protective equipment (PPE) like face shields or masks, as well as adherence to safety protocols while handling acetic acid. Regular health monitoring of individuals working with or living near acetic acid production facilities can also help in early detection and management of any health issues related to acetic acid exposure.

Conclusion

However useful it might be, glacial acetic acid is a deadly chemical, and manufacturers like LyondellBasell know that. The success that comes from being one of the world’s largest acetic acid producers comes with a responsibility to store and handle that chemical as safely as possible. Negligence has dire consequences.