This article discusses poisoning from mercury.
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 centre. Their contact information will vary by city and province, but can generally be reached by telephone 24 hours a day, seven days a week. You can find select contact numbers for Canadian centres here.
There are three different forms of mercury that cause health problems. They are:
- Elemental mercury, also known as liquid mercury or quicksilver
- Inorganic mercury salts
- Organic mercury
Elemental mercury can be found in:
- Glass thermometers
- Electrical switches
- Fluorescent light bulbs
- Dental fillings
- Some medical equipment
Inorganic mercury can be found in:
- Chemistry labs
- Some disinfectants
- Folk remedies
- Red cinnabar mineral
Organic mercury can be found in:
- Older germ-killers (antiseptics) such as red mercurochrome (merbromin) (this substance is now banned by the FDA)
- Fumes from burning coal
- Fish that have eaten a form of organic mercury called methylmercury
There may be other sources of these forms of mercury.
Elemental mercury is usually harmless if it is touched or swallowed. It is so thick and slippery that it usually falls off the skin or leaves the stomach and intestines without being absorbed.
A lot of damage can occur, though, if elemental mercury gets into the air in the form of small droplets that are breathed into the lungs. This often occurs by mistake when people try to vacuum up mercury that has spilled onto the ground.
Breathing in enough elemental mercury will cause symptoms right away. These are called acute symptoms. Long-term symptoms will occur if small amounts are inhaled over time. These are called chronic symptoms. Chronic symptoms may include:
Depending on how much mercury is inhaled, permanent lung damage and death may occur. Long-term brain damage from inhaled elemental mercury can also occur.
There have been cases of mercury being injected under the skin, which can cause fever and rash.
Unlike elemental mercury, inorganic mercury is usually poisonous when swallowed. Depending on how much is swallowed, symptoms may include:
- Burning in the stomach and throat
- Bloody diarrhea and vomiting
If inorganic mercury enters your bloodstream, it can attack the kidneys and brain. Permanent kidney damage and kidney failure may occur. A large amount in the bloodstream may cause massive blood and fluid loss from diarrhea and kidney failure, leading to death.
Organic mercury can cause sickness if it is breathed in, eaten, or placed on the skin over long periods of time. Usually, organic mercury causes problems over years or decades, not right away. This means that being exposed to small amounts of organic mercury every day for years will likely cause symptoms to appear later. A single large exposure, however, can also cause problems.
Long-term exposure will likely cause symptoms in the nervous system, including:
- Numbness or pain in certain parts of your skin
- Uncontrollable shaking or tremor
- Inability to walk well
- Blindness and double vision
- Memory problems
- Seizures and death (with large exposures)
Being exposed to large amounts of the organic mercury called methylmercury while pregnant may cause permanent brain damage in the baby. Most health care providers recommend eating less fish, especially swordfish, while pregnant. Women should talk to their provider about what they should and should not eat while pregnant.
Before Calling Emergency
Have this information ready:
- Person’s age, weight and condition (for example, is the person awake and alert?)
- Source of the mercury
- Time it was swallowed, inhaled, or touched
- Amount swallowed, inhaled, or touched
DO NOT delay calling for help if you do not know the above information.
Your local poison centre’s contact information will vary by city and province, but can generally be reached by telephone 24 hours a day, seven days a week. You can find select contact numbers for Canadian centres here.
What to Expect at the Emergency Room
General treatment for mercury exposure includes the steps just below. Treatment for exposure to different forms of mercury are given after this general information.
The person should be moved away from the source of exposure.
The health care provider will measure and monitor the person’s vital signs, including temperature, pulse, breathing rate and blood pressure.
Tests that may be done include:
- Blood and urine tests
- Chest x-ray
- ECG (electrocardiogram) or heart tracing
Treatment may include:
- Activated charcoal by mouth or tube through the nose into the stomach, if mercury is swallowed
- Dialysis (kidney machine)
- Fluids through a vein (by IV)
- Medicine to treat symptoms
The type of exposure will determine what other tests and treatments are needed.
Inhaled elemental mercury poisoning may be difficult to treat. The person may receive:
- Humidified oxygen or air
- Breathing tube through the mouth into the lungs and use of a breathing machine (ventilator)
- Suctioning of mercury out of the lungs
- Medicine to remove mercury and heavy metals from the body
- Surgical removal of the mercury if injected under the skin
For inorganic mercury poisoning, treatment often begins with supportive care. The person 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
Treatment for exposure to organic mercury usually consists of medicines called chelators. These remove mercury from the blood and move it away from the brain and kidneys. Often, these medicines will have to be used for weeks to months.
Breathing in a small amount of elemental mercury will cause very few, if any, long-term side effects. However, breathing in larger amounts can lead to a long hospital stay. Permanent lung damage is likely. There may be 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 poisoning is difficult to treat. Some people never recover, but there has been some success in people who receive chelation treatment.
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Theobald JL, Mycyk MB. Iron and heavy metals. In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen’s Emergency Medicine: Concepts and Clinical Practice. 9th ed. Philadelphia, PA: Elsevier; 2018:chap 151.