Symptomatology depends on many factors: the chemical form of mercury, its accumulation in specific tissues, presence of other toxicants, presence of disease that depletes glutathione or inactivates lymphocytes or is immunosuppressive, and the concentration of protective nutrients, (e.g. zinc, selenium).
Early signs of excessive mercury exposure include:
- decreased senses of touch, hearing, vision and taste,
- metallic taste in mouth,
- fatigue or lack of physical endurance,
- and increased salivation.
Symptoms may progress with moderate or chronic exposure to include:
- anorexia,
- numbness and paresthesias,
- headaches,
- hypertension,
- irritability and excitability,
- and immune suppression/ dysregulation.
Advanced disease processes from excessive Hg assimilation include:
- tremors and incoordination,
- anemia,
- psychoses,
- manic behaviors,
- possibly autoimmune disorders and renal dysfunction or failure.
Note that in mercury exposure of long duration, renal excretion of mercury (and normal metabolites) may become impaired, and the urine level of mercury might be only mildly elevated or not elevated at all due to renal failure.
Mercury is used in:
- dental amalgams (50% by weight),
- explosive detonators;
- some vaccines,
- pure liquid form in thermometers,
- barometers, and laboratory equipment;
- batteries and electrodes,
- some medications and Ayurveic herbs,
- fungicides and pesticides,
- and in the paper industry.
The fungicide/pesticide use of mercury has declined due to environmental concerns, but mercury residues persist in the environment. Emissions from coalfired power plants and hospital/municipal incinerators are significant sources of mercury pollution.
Methylmercury, the most common, organic form of mercury, occurs by methylation of inorganic Hg in aquatic biota or sediments (both freshwater and ocean sediments).
Methylmercury accumulates in aquatic animals and fish and is concentrated up the food chain reaching highest concentrations in large fish and predatory birds.
Except for fish, the human intake of dietary mercury is negligible unless the food is contaminated with one of the previously listed forms/sources. Daily ingestion of fish can result in the assimilation of 1 to 10 micrograms of mercury/day.
Depending upon the extent of cumulative mercury exposure, elevated levels of urine mercury may occur after administration of DMPS, DMSA or D-penicillamine. Blood and especially red blood cell elemental analyses are useful for assessing recent or ongoing exposure to organic (methyl) mercury.
The fungicide/pesticide use of mercury has declined due to environmental concerns, but mercury residues persist in the environment. Emissions from coalfired power plants and hospital/municipal incinerators are significant sources of mercury pollution.
Methylmercury, the most common, organic form of mercury, occurs by methylation of inorganic Hg in aquatic biota or sediments (both freshwater and ocean sediments).
Methylmercury accumulates in aquatic animals and fish and is concentrated up the food chain reaching highest concentrations in large fish and predatory birds.
Except for fish, the human intake of dietary mercury is negligible unless the food is contaminated with one of the previously listed forms/sources. Daily ingestion of fish can result in the assimilation of 1 to 10 micrograms of mercury/day.
Depending upon the extent of cumulative mercury exposure, elevated levels of urine mercury may occur after administration of DMPS, DMSA or D-penicillamine. Blood and especially red blood cell elemental analyses are useful for assessing recent or ongoing exposure to organic (methyl) mercury.
Mercury is often abbreviated Hg. It may be breathed in, ingested or absorbed through the skin and is toxic. As a vapor, mercury is odorless.
Urinary mercury testing is considered a very accurate way to assess whether or not you have been exposed to the inorganic form of the heavy metal. There is also an organic form of mercury, which can become toxic in the body but this form of mercury is best detected in a blood test sample.
A urine mercury test measures mercury excretion from the body over 24 hours, both before and after a “provocation” or “detox” compound is ingested. A provocation compound increases the excretion of a substance such as toxic metals. EDTA, DMSA, and DMPS are examples of provocation compounds.
Mercury
