ADAM Health Encyclopedia

Mercury

Definition

This article discusses poisoning from mercury.

Poisonous Ingredient

There are three different forms of mercury that cause health problems.

• Elemental mercury, also known as liquid mercury or quick silver
• Inorganic mercury salts
• Organic mercury

Where Found

Elemental mercury can be found in:

• Glass thermometers
• Electrical switches
• Fluorescent light bulbs
• Older dental fillings
• Some medical equipment

Inorganic mercury can found in:

• Chemistry labs
• Some disinfectants
• Folk culture medicines
• Red cinnabar mineral

Organic mercury can be found in:

• Older antiseptics, such as red mercurochrome (merbromin) -- this substance is now banned by the FDA
• Thimerosal
• Fumes from burning coal converted into organic mercury by certain organisms
• Fish that have eaten a form of organic mercury called methylmercury -- see article on methylmercury

Note: This list may not be all inclusive.

Symptoms

ELEMENTAL MERCURY

Elemental mercury is usually quite harmless if touched or swallowed. It is so thick and slippery that it usually falls off your skin or out of your stomach without being absorbed.

Considerable damage can occur, however, if mercury is made airborne into small, little droplets and breathed into the lungs. This can often occur by mistake when people try to vacuum up mercury that has spilled onto the ground.

Breathing in elemental mercury will cause symptoms right away (acute) if enough mercury is breathed in. Symptoms will also occur over time (chronic) if little amounts are inhaled every day. If this occurs, symptoms may include:

• Metallic taste
• Vomiting
• Difficulty breathing
• Bad cough
• Swollen, bleeding gums

Depending on how much mercury is inhaled, permanent lung damage and death may occur. You may also have some long-term brain damage from inhaled elemental mercury.

INORGANIC MERCURY

Unlike elemental mercury, inorganic mercury is usually poisonous when swallowed. Depending on the how much is swallowed, symptoms may include:

• Burning in the stomach and throat
• Bloody diarrhea and vomiting

If inorganic mercury enters your blood stream, it can attack the kidneys and brain. Permanent kidney damage and failure may occur. A large overdose may cause massive blood and fluid loss from diarrhea, kidney failure, and death.

ORGANIC MERCURY

Organic mercury can cause sickness if breathed in, eaten, or placed on the skin for long periods of time. Usually organic mercury causes problems over years or decades, not immediately. In other words, being exposed to small amounts of organic mercury every day for years will likely cause symptoms to appear later. Regardless, a single large exposure can also cause problems.

Long-term exposure will likely cause neurological symptoms, including:

• Numbness or pain in certain parts of your skin
• Uncontrollable shake or tremor
• Inability to walk well
• Blindness and double vision
• Memory problems
• Seizures and death (with large exposures)

Medical evidence suggests that being exposed to large amounts of the organic mercury called methylmercury while pregnant can permanently damage the baby’s developing brain. Most doctors will recommend eating less fish, especially swordfish, while pregnant. These recommendations are made to be extremely cautious. Small exposures are unlikely to cause any problems. Women should talk to their doctor about what should and should not be eaten while pregnant.

Before Calling Emergency

Determine the following:

• The patient's age, weight, and condition
• The name of the product (ingredients and strengths if known)
• The time it was swallowed, inhaled, or touched
• The amount swallowed, inhaled, or touched

The National Poison Control Center (1-800-222-1222) can be called from anywhere in the United States. This national hotline number 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 U.S. 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.

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

See National Poison Control center.

What to Expect at the Emergency Room

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

ELEMENTAL MERCURY

Inhaled elemental mercury poisoning may be difficult to treat. The patient may receive:

• Humidified oxygen or air
• Breathing tube into the lungs
• Suctioning of mercury out of the lungs
• Medication to remove mercury and heavy metals from the body

INORGANIC MERCURY

For inorganic mercury poisoning, treatment usually begins with supportive care. The patient may receive:

• Fluids by IV (into a vein)
• Medicines to treat symptoms
• Activated charcoal, a medicine that soaks up many substances from the stomach
• Medicines called chelators to remove mercury from the blood

ORGANIC MERCURY

Treatment of organic mercury usually consists of medicines called chelators to remove mercury from the blood and away from the brain and kidneys. Often, these medications will have to be used for weeks to months.

Outlook (Prognosis)

Breathing in a small amount of elemental mercury will cause very few, if any, long-term side effects. However, larger amounts will lead to a long hospital stay. Permanent lung damage is likely. There may be some brain damage. Very large exposures will likely cause death.

A large overdose of inorganic mercury may cause massive blood and fluid loss, kidney failure, and likely death.

Chronic brain damage from organic mercury is difficult to treat. Although some people never recover, some success has been described in patients treated with chelation.

Sue YJ. Mercury. In: Goldfrank LR, Flomenbaum NE, Lewin NA, et al. Goldfrank's Toxicologic Emergencies. 7th ed. McGraw-Hill; 2002:1239-1247.

Ford MD. Clinical Toxicology. 1st ed. Philadelphia, Pa: WB Saunders; 2001: 732-742.

Foulke JE. Mercury in Fish: A Cause for Concern. FDA Consumer Magazine. September 1994.