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Heavy Metal Toxicity

The Effects of Mercury on Health

Dec 19, 2007 Elaine Moore

Mercury is the most common source of heavy metal toxicity and dental amalgams are the primary source of mercury exposure.

Heavy metals, including mercury, lead, bismuth, arsenic, aluminum, cadmium, chromium, copper, gold, iron, manganese, nickel, silver, tin, titanium, zinc, and antimony, are considered one of the worst environmental threats to health. The term heavy metal refers to high specific gravity, which is the metals’ weight compared to the weight of an equal volume of water. Lead used to account for most heavy metal poisoning. Today, mercury, which is also known as quicksilver, is the most common cause of heavy metal toxicity.

Mercury Toxicity

Mercury toxicity has been reported since the first century when Roman prisoners were sentenced to work in cinnabar mines. This was considered a death sentence because of the lethal levels of mercury found in cinnabar.

In the early 1800s hat makers exposed to mercury suffered from a mercury-induced psychosis, which led to the phrase. “mad as a hatter.” Insanity was also reported in patients with syphilis who were treated with mercury in the mid-19th century.

Effects of Mercury

Mercury affects health in many ways, including:

Reduced effectiveness of antibiotics against bacteria
Abnormally low-voltage electrocardiograms (depressed heart function)
Contributes to the development of cancerous and pre-cancerous cells
Decreases levels of brain neurotransmitters, including serotonin, contributing to depression, anger, anxiety and addictions
Damages kidney cells (nephrotoxic)
Acts as an endocrine disruptor, in particular depressing the pituitary gland
Reduces blood supply to the developing fetus
Causes learning disabilities
Damages the immune system, resulting in allergies, asthma, and autoimmune diseases

Sources of Mercury

People today are exposed to tremendous amounts of mercury. According to the Environmental Protection Agency (EPA) dental amalgam is the primary source of exposure. Studies show that the form of mercury released from dental fillings is far more prevalent than mercury compounds found in contaminated fish.

According to the World Health Organization and Health Canada, mercury levels in people with amalgam fillings cause a body burden of mercury much higher than that found in people who eat fish from Florida waters, known to have excess mercury. Dental amalgam is also responsible for 65 percent of the mercury contaminants found in San Francisco Bay (San Francisco Environmental Commission Report).

Contaminated fish rank second as sources of mercury, followed by drugs and vaccines. The influenza vaccine contains mercury, which is of special concern to pregnant women and people with autoimmune diseases. The fourth most common cause of mercury exposure is fertilizer produced by recycled toxic waste.

Body Burden

The body burden of mercury can be estimated by evaluating the number of silver amalgam fillings a person has, the presence of root canals, which contain up to 20 percent toxic metals, mainly mercury and lead, how often fish is consumed and what type. Symptoms that suggest a body burden of mercury include:

Fatigue
Tingling or numbness around mouth, face, fingers or toes
Joint problems
Headaches
Tremors
Hearing Loss
Gait and balance disturbances
Mood swings
Agitation
Depression
Gastroenteritis
Elevated MCH and MCV on complete blood count (CBC) tests
Elevated liver enzymes
Low CD8 count or elevated CD4/CD8 ratio
Changes in fractionated urine porphyrins
High urinary mercapturic acid

Diagnosing Mercury Toxicity

Blood, urine and stool samples can be used to test for mercury. Ideally, a metal challenge is given in which a chelator is first ingested that releases stored mercury. Hair can also be tested for mercury, but results can be affected by hair dyes, bleaches, perms, and straighteners. Hair analysis of mercury reflects the person’s condition for the last three months. Muscle testing can also be used to assess heavy metal toxicity.

Resource:

Pamela Levin, "From mad hatters to dental amalgams: heavy metals: toxicity and testing", Medical Laboratory Observer, December 2007, 20-24.

The copyright of the article Heavy Metal Toxicity in General Medicine is owned by Elaine Moore. Permission to republish Heavy Metal Toxicity in print or online must be granted by the author in writing.

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