Skip all navigation Skip to page navigation

DHHS Home | A-Z Site Map | Divisions | About Us | Contacts

NC Department of Health and Human Services
NC Division of Public Health
N.C. Public Health Home

Occupational & Environmental Epidemiology

Sulfuric Acid

Sulfuric acid (H2SO4) is a corrosive, oily, colorless liquid in a pure state. Impure grades of sulfuric acid are brownish in color. Sulfuric acid is most often used in the manufacture of fertilizers, explosives, other acids and glue.  In addition, it is also used for the pickling or cleaning of metal surfaces. Most car batteries contain sulfuric acid, as do some commonly used household drain and toilet cleaners.

Sulfuric acid releases in North Carolina have resulted in injuries, hospitalizations, and workplace evacuations. Some examples of sulfuric acid release incidents in North Carolina include:

  • A chemist mixed sulfuric acid with several other chemicals for a routine experiment, which caused a small explosion. He suffered minor injuries to his hands and was transported to the hospital by ambulance. Over 100 employees were evacuated from the building.
  • An employee of a janitorial supply store was filling an overhead storage tank with a bucket of sulfuric acid when the ladder slipped, causing him to spill five gallons of acid on his body. He was admitted to the hospital with second-degree chemical burns over 40 percent of his body.
  • Employees who were trying to clear a drain mixed sulfuric acid and bleach, causing a chemical reaction. The gas released caused respiratory irritation, eye irritation and nausea to the employees. They received treatment at the scene from Emergency Medical Services personnel.
  • A professional firefighter in turnout gear suffered respiratory irritation while extinguishing a fire of automotive batteries in a trailer. He was treated at the hospital.
  • An overcharged battery burst at a retail auto parts store. One employee was transported to and treated at the hospital for respiratory irritation.
  • Drain cleaner containing sulfuric acid was spilled at a daycare. Sixty-eight children and faculty were evacuated from the facility for one hour. One employee was treated at the hospital for respiratory irritation.
  • A chemist, mixing 96 percent sulfuric acid, cracked the beaker. He was using gloves and eye protection, but was still chemically burned and required treatment at a hospital.

Common Routes of Exposure

Inhalation. The most common way for sulfuric acid to enter the body is through the respiratory system. Serious lung damage may result from inhalation exposure to sulfuric acid.

Skin Contact. Sulfuric acid can irritate the skin and cause chemical burns ranging from mild to severe, depending on the concentration of the sulfuric acid solution. Concentrated vapor or solution that contacts the skin may cause the victim to experience severe pain, redness of the skin, blisters and permanent scarring.

Eye Contact. Sulfuric acid or sulfuric acid vapor, even with short-term exposure, can irritate the eyes and cause burning, swelling, tearing of the eyes and/or blurred vision, and may cause blindness.

Ingestion. Immediate burning in the mouth and throat occur when sulfuric acid is swallowed. Ingestion of concentrated solution can cause severe pain in the mouth, chest and abdomen, nausea and vomiting, or holes in the esophagus.

Acute Health Effects

As the concentration of sulfuric acid increases, the symptoms become more severe. Acute exposures to sulfuric acid can cause immediate burning of the eyes. Itchy, burning eyes can help to warn people of potentially hazardous exposure levels. The very young, the very old, and people with health problems are at an increased risk from the health effects of sulfuric acid exposure.

Chronic Health Effects

Erosion of the teeth, inflammation of mouth, narrowing of stomach or esophagus, chronic bronchial irritation with cough, and/or chronic shortness of breath may occur with repeated or long-term exposure to sulfuric acid. Skin rashes may also occur with repeated exposures of dilute concentrations of sulfuric acid.


Sulfuric acid can be found in many car batteries (lead-acid batteries) and in household products like drain and toilet bowl cleaners. Be sure to read product labels carefully, and do not use more than one product per application. Even some chemical residue in a drain or on a surface can be hazardous if combined with a second product.

  • Know which products in your home contain sulfuric acid, and keep those products out of the reach of children and pets.
  • Wear protective gloves when using products that contain sulfuric acid. Eye protection is also recommended, particularly when using a product that may splash.
  • Keep car batteries away from children.
  • Avoid breathing smoke or fumes where coal, oil, or gas are burned, even outside.
  • Avoid touching the material that forms on the outside of your car battery.
  • Keep the Carolinas Poison Center 24/7 number 1-800-222-1222 and other emergency numbers near or programmed into your phone.

For Additional Information