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URL of this page: //medlineplus.gov/ency/article/002830.htm

Acid soldering flux poisoning

Acid soldering flux is a chemical used to clean and protect the area where two pieces of metal are joined together. Flux poisoning occurs when someone swallows this substance.

This article is for information only. DO NOT use it to treat or manage an actual poison exposure. If you or someone you are with has an exposure, call your local emergency number (such as 911), or your local poison control center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere in the United States.

Poisonous Ingredient

The harmful substances in soldering fluxes are called hydrocarbons. They include:

  • Ammonium chloride
  • Rosin
  • Hydrochloric acid
  • Zinc chloride

Where Found

Soldering flux contains the above substances.

Other products may also contain fluxes.

Symptoms

Below are symptoms of flux poisoning in different parts of the body.

EYES, EARS, NOSE, AND THROAT

  • Loss of vision
  • Severe pain in the throat
  • Severe pain or burning in the nose, eyes, ears, lips, or tongue

KIDNEYS AND BLADDER

  • Decreased urine output
  • Kidney failure

STOMACH AND INTESTINES

HEART AND BLOOD VESSELS

LUNGS AND AIRWAYS

  • Breathing difficulty (from breathing in the chemical)
  • Throat swelling (which may also cause breathing difficulty)

SKIN

  • Burn
  • Holes in the skin or tissues under the skin
  • Irritation

Home Care

Get medical help right away. Do not make the person throw up unless poison control or a health care provider tells you to. If the flux is on the skin or in the eyes, flush with lots of water for at least 15 minutes.

If the person swallowed the flux, give them water or milk right away if poison control or a provider tells you to do so. Do not give anything to drink if the person has symptoms that make it hard to swallow. These include vomiting, seizures, or a decreased level of alertness.

If the person breathed in fumes of the flux, move them to fresh air right away.

Before Calling Emergency

Have this information ready:

  • Person's age, weight, and condition
  • Name of the product (and ingredients, if known)
  • Time it was swallowed
  • Amount swallowed

Poison Control

Your local poison control center can be reached directly by calling the national toll-free Poison Help hotline (1-800-222-1222) from anywhere in the United States. This national hotline will let you talk to experts in poisoning. They will give you further instructions.

This is a free and confidential service. All local poison control centers in the United States use this national number. You should call if you have any questions about poisoning or poison prevention. It does NOT need to be an emergency. You can call for any reason, 24 hours a day, 7 days a week.

What to Expect at the Emergency Room

Take the container with you to the hospital, if possible.

The provider will measure and monitor the person's vital signs, including temperature, pulse, breathing rate, and blood pressure.

Tests that may be done include:

Treatment may include:

  • Fluids through the vein (by IV)
  • Medicine to treat symptoms
  • Tube through the mouth into the stomach to wash out the stomach (gastric lavage)
  • Washing of the skin (irrigation), perhaps every few hours for several days
  • Surgery to remove burned skin
  • Breathing support, including tube through the mouth into the lungs and connected to a breathing machine (ventilator)

Outlook (Prognosis)

How well someone does depends on how severe their poisoning is and how quickly treatment is received. The faster medical help is given, the better the chance for recovery. Damage can continue to occur for several weeks after swallowing soldering flux.

Swallowing such poisons can have severe effects on many parts of the body. Burns in the airway or gastrointestinal tract can lead to tissue necrosis, resulting in infection, shock, and death, even several months after the substance was first swallowed. Scars may form in these tissues, leading to long-term difficulties with breathing, swallowing, and digestion.

Alternative Names

Fluxes; Flux poisoning

References

Aronson JK. Organic solvents. In: Aronson JK, ed. Meyler's Side Effects of Drugs. 16th ed. Waltham, MA: Elsevier; 2016:385-389.

Hoyte C. Caustics. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 143.

Wang GS, Buchanan JA. Hydrocarbons. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 147.

Review Date 11/2/2023

Updated by: Jesse Borke, MD, CPE, FAAEM, FACEP, Attending Physician at Kaiser Permanente, Orange County, CA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.