Published: 18 Jun 2025

ICD9: 985.0      ICD10: T54.1X4A      ICD11: NE61

Mercury poisoning is a condition that occurs when someone is exposed to excessive amounts of mercury.
Mercury is a naturally occurring element that can be found in three forms:

Elemental (or metallic) mercury: This form is found in thermometers, old dental fillings (amalgams), and some electrical appliances.
Inorganic mercury compounds: These compounds are found in some batteries, disinfectants, and certain industrial processes.
Organic mercury compounds: Methylmercury is the most common organic mercury compound, and it's formed when mercury enters water bodies and is converted by microorganisms. This form is most often associated with food contamination, particularly in fish.

Here's a more detailed breakdown:

How Exposure Happens:

Ingestion: Eating contaminated food, especially fish high in methylmercury (like swordfish, tuna, shark, and king mackerel).
Inhalation: Breathing mercury vapors, often from spills of elemental mercury or from industrial processes. This is a significant risk for workers in certain industries (mining, manufacturing).
Skin contact: While less common, skin contact with certain mercury compounds can lead to absorption and poisoning.
Prenatal exposure: Pregnant women who are exposed to mercury can pass it on to their developing fetus.

Symptoms:

The symptoms of mercury poisoning vary depending on the form of mercury, the dose, the route of exposure, and the age and health of the individual. Here's a general overview, but symptoms can be subtle at first:

Neurological:
Tremors
Numbness or tingling in hands, feet, and around the mouth
Memory problems
Irritability, anxiety, or mood swings
Difficulty concentrating
Headaches
Incoordination
Vision changes
Speech difficulties
Muscle weakness
In severe cases: seizures, coma, and death

Kidney damage: Mercury can damage the kidneys, leading to protein in the urine (proteinuria) and kidney failure.

Gastrointestinal:
Nausea
Vomiting
Diarrhea
Abdominal pain

Skin: Rashes or skin irritation (especially with direct contact).

Cardiovascular: Some studies suggest links to increased risk of heart problems.

Children: In children, mercury poisoning can affect neurological development, leading to learning disabilities, developmental delays, and speech problems. Prenatal exposure is particularly concerning.

Specific Symptoms by Mercury Type:

Elemental Mercury: Primary concern is inhalation of vapors. Symptoms often include tremors, emotional changes, insomnia, neuromuscular changes, headaches, and impaired cognitive function. Inhaling large amounts can cause lung damage.

Inorganic Mercury: Can cause kidney damage, gastrointestinal issues, and neurological problems. Skin contact can cause irritation.

Organic Mercury (Methylmercury): Primarily affects the nervous system. Symptoms can include numbness and tingling, vision problems, coordination issues, and memory problems. Developmental problems are a major concern with prenatal exposure.

Diagnosis:

Diagnosis typically involves:

Medical history and physical exam: The doctor will ask about possible exposures and perform a physical examination.
Blood tests: To measure mercury levels in the blood.
Urine tests: To measure mercury levels in the urine.
Hair analysis: Can provide a longer-term assessment of exposure to methylmercury.
Other tests: Depending on the symptoms, other tests may be ordered to assess kidney function, neurological function, etc.

Treatment:

The goal of treatment is to remove mercury from the body and manage the symptoms.

Removal from Exposure: The most important step is to stop the exposure to mercury.
Chelation Therapy: Chelating agents (like succimer, dimercaprol, or penicillamine) can bind to mercury in the body and help eliminate it through the urine. Chelation therapy is not without risks and is generally reserved for cases of significant poisoning. The decision to use chelation therapy depends on the severity of the poisoning, the type of mercury involved, and the individual's overall health.
Supportive Care: Treatment may also include supportive care to manage symptoms, such as medications for nausea, pain relief, and treatment for kidney problems.

Prevention:

Be aware of the risks of mercury exposure: Understand the sources of mercury and how you can be exposed.
Follow fish consumption guidelines: Pregnant women, breastfeeding mothers, and young children should be especially careful about limiting their consumption of fish that may be high in mercury. Check for advisories issued by local or state health departments.
Handle mercury-containing products carefully: Be careful when handling thermometers, fluorescent light bulbs, and other products that contain mercury. If a mercury spill occurs, follow proper cleanup procedures (often best left to professionals).
Occupational safety: Workers in industries that use mercury should follow safety protocols to minimize exposure.
Dental amalgams: While dental amalgams do release small amounts of mercury vapor, most health organizations consider them safe for most people. If you have concerns, discuss them with your dentist.

Important Considerations:

Vulnerability: Pregnant women, developing fetuses, infants, and young children are particularly vulnerable to the effects of mercury poisoning.
Severity: The severity of mercury poisoning depends on the amount and duration of exposure, as well as the individual's overall health.
Long-term effects: Mercury poisoning can have long-term effects on the nervous system, kidneys, and other organs.
Seek medical attention: If you suspect you have been exposed to mercury and are experiencing symptoms, seek medical attention promptly.

Disclaimer: This information is for general knowledge purposes only and does not constitute medical advice. It is essential to consult with a qualified healthcare professional for any health concerns or before making any decisions related to your health or treatment.