Mercury is an extremely heavy, odorless, silver colored liquid. Mercury exists as a natural element in the earth's crust. Elemental mercury is also known as metallic mercury, liquid mercury, liquid silver and quicksilver.

What are sources of exposure to elemental mercury?

Sources of elemental mercury in the home include broken mercury thermometers, broken fluorescent light bulbs, dental amalgam fillings, mercury containing latex paints, extraction of gold from ore using mercury, and contaminated clothing from workers in thermometer making plants.

How toxic is elemental mercury?

Of all the forms of mercury, elemental mercury is the most commonly swallowed form of mercury, usually from a broken thermometer. Fortunately, elemental mercury from a thermometer is not absorbed from the stomach and will not cause any poisoning in a healthy person.

In a healthy person, the slippery swallowed mercury will roll into the stomach, out in to the bowels and will be quickly eliminated without causing any symptoms. A person with severe inflammatory bowel disease or those with a fistula (hole or opening) in their gut may have problems with mercury if it is not all cleared out, resulting in prolonged exposure.

Handling liquid mercury for a very short period of time usually does not result in any problems. An allergic rash is possible, though. Mercury is not well absorbed across the skin so skin contact is not likely to cause mercury poisoning, especially with a brief one-time exposure. Even if a person has cuts in their skin, mercury is too heavy to be contained by a cut. Merely washing the wound well will wash the mercury out of the wound.

Can elemental mercury be dangerous?

Inhalation of elemental mercury vapors is the main cause of toxicity, as mercury is well absorbed by the lungs. To develop problems by inhalation you need either a large one-time exposure or a long-term exposure. A small, one-time exposure is not likely to cause problems.

What are the symptoms?

After a large, one-time inhalation exposure of mercury vapor, the lungs are the main target of mercury poisoning, although other symptoms develop as well.

Symptoms may develop within a few hours and include chills, metallic taste, mouth sores, swollen gums, nausea, vomiting, abdominal pain, diarrhea, headache, weakness, confusion, shortness of breath, cough, chest tightness, bronchitis, pneumonia and kidney damage.

How does long-term exposure differ from a short-term exposure?

Long-term exposure (usually work-related) of inhaled vapors is generally more dangerous than a one-time short exposure. After long-term inhalation exposure, the nervous system is the main target of toxicity. Symptoms may occur within weeks but usually develop insidiously over a period of years.

Neurologic symptoms include tremors, headaches, short-term memory loss, incoordination, weakness, loss of appetite, altered sense of taste and smell, numbness and tingling in the hands and feet, insomnia, and excessive sweating. Psychiatric effects are also seen after long-term exposure.

Inorganic Mercury

Inorganic mercury compounds are known as "mercuric salts." Some of the mercuric salts include: mercuric chloride, mercuric iodide, mercuric nitrate, mercuric sulfide, yellow mercuric oxide, red mercuric oxide, ammoniated mercury, mercurous chloride and mercurous acetate.

What are the symptoms of inorganic mercury poisoning?

Inorganic mercuric salts are corrosive and they damage the kidneys. Following ingestion, symptoms include nausea, vomiting blood, burns and tissue death in the throat and stomach, abdominal pain, bloody diarrhea, decreased urination and kidney failure.

Long-term application of mercury-containing substances causes skin redness and staining of the skin. More severe symptoms include nerve damage resulting in weakness, numbness and tingling.

What are sources of organic mercury?

Organic mercury compounds are found in a variety of products. They are used medically as fungicides and antibacterials. The most common organic mercury compounds in the home may well be mercurochrome (merbromin) and merthiolate (thimerosal), two common antiseptics. Fortunately, small ingestions by children rarely cause major problems.

What is the most common source of organic mercury poisoning?

In the general population, the main source of mercury poisoning is the ingestion of mercury- contaminated food, usually fish. When lake, river or ocean water is contaminated with methyl-mercury compounds, the mercury accumulates and magnifies in the flesh of the fish. Organic mercury concentrations can be more than 1,000 times greater in the fish than in the surrounding water. People who eat fish as a main component of their diet may be at risk. If a river or lake is known to be polluted with mercury, fish eaters are warned to decrease their weekly intake of fish. What are the signs and symptoms of organic mercury poisoning?

Organic mercury compounds are very damaging. They are toxic by ingestion, inhalation, and skin and eye contact. These mercury compounds can attack all body systems. They can cause nausea, vomiting, lack of appetite, weight loss, abdominal pain, diarrhea, kidney failure, skin burns and irritation, respiratory distress, swollen gums and mouth sores, drooling, numbness and tingling in the lips, mouth, tongue, hands and feet, tremors and incoordination, vision and hearing loss, memory loss, personality changes and headache. Allergic reactions can also occur.

What is Methyl-mercury?

Methyl-mercury, usually from contaminated food, is very dangerous to pregnant women. Methyl-mercury causes profound mental retardation, cerebral palsy, seizures, spasticity, tremors, and incoordination, along with eye and hearing damage in the unborn baby as a result of the mother's exposure. Organic mercury passes into the breast milk as well. How is mercury poisoning diagnosed and treated?

How can mercury poisoning be diagnosed?

Because the number of symptoms is so great and the variety of symptoms is so wide, anyone could pick out at least 2 or 3 symptoms at any given time. If you have any doubt and if you have been or are exposed to mercury compounds, see a physician and get tested. Testing is the only definite way to determine if mercury is the cause of the symptoms.

Mercury poisoning can be diagnosed by special blood and urine collection tests. If levels are high, there is treatment. Medication can be administered to help bind the mercury and increase elimination. Symptoms do not always correspond to blood mercury levels: Many patients with high levels do not have severe symptoms.