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Mercury Poisoning

Mercury is a bioaccumulative toxin that is easily absorbed through the skin, respiratory and gastrointestinal tissues. Minamata disease is a form of mercury poisoning.

mercury poisoning symptoms

Mercury attacks the central nervous system and endocrine system and adversely affects the mouth, gums, and teeth. High exposure over long periods of time will result in brain damage and ultimately death. It can pose a major health risk to the unborn fetus. Air saturated with mercury vapor at room temperature is at a concentration many times the toxic level, despite the high boiling point (the danger is increased at higher temperatures).

symptoms of mercury poisoning - low dose exposure

• Erethism (nervousness, irritability, mood instability, blushing)
• Tremor
• Personality change
• Suicidal tendency
• Paraesthesia
• Impaired hearing
• Speech disorders
• Visual disturbance
• Abnormal reflexes
• Disturbed gait
• Gingivitis (inflammation of the gums)
• Impaired nerve conduction
• Renal damage
• Adverse outcome of pregnancy
• Infertility
• Pneumonitis (lung disease)
• Glioblastoma (brain cancer)
• Immune system dysfunction

symptoms of mercury poisoning - High-Dose Exposure

• Gastroenteritis (stomach upset)
• Mouth pain
• Abdominal pain
• Vomiting
• Excessive salivation
• Anuria (urine production stops)
• Uraemia (urine products appearing in the blood)
• Nephritis (kidney disease leading to kidney failure)
• Anorexia (lack of appetite)
• Ataxia (difficulty in moving)

One of the most dangerous mercury compounds, dimethylmercury, is so toxic that even a few microliters spilled on the skin can cause death. One of the chief targets of the toxin is the enzyme pyruvate dehydrogenase (PDH). The enzyme is irreversibly inhibited by several mercury compounds, the lipoic acid component of the multienzyme complex binds mercury compounds tightly and thus inhibits PDH.

Mercury Amalgams and Mercury Poisoning

Elemental mercury is the main ingredient in dental amalgams. Controversy over the health effects from the use of mercury amalgams began shortly after its introduction into the western world, nearly 200 years ago. In 1843, The American Society of Dental Surgeons, concerned about mercurial poisoning, required its members to sign a pledge that they would not use amalgam. In 1859, The American Dental Association was formed by dentists who believed amalgam was, "safe and effective." The ADA, "continues to believe that amalgam is a valuable, viable and safe choice for dental patients," as written in their statement on dental amalgam. In 1993, the United States Public Health Service reported that, "amalgam fillings release small amounts of mercury vapor," but in such a small amount that it, "has not been shown to cause any … adverse health effects." In 2002, California became the first state to ban the future use of mercury fillings (effective 2006). As of 2005, the controversy continues,..

The dental amalgam controversy centers around the use of amalgam fillings in teeth. An amalgam is a mixture of metals, 50% of which is typically mercury. It has been used in dentistry for nearly 200 years because it is malleable, durable and more affordable than gold or composites. The American Dental Association has supported the use of amalgam since its inception in 1859. Proponents once thought the combination of metals in an amalgam rendered the mercury inert. This is now known not to be the case; mercury vapors do leach from fillings into the body. The severity of mercurial toxicity depends on the form and length of exposure.

The ADA's position states that the amount of mercury released by amalgam fillings is negligible. As of December 2002, FDA investigations reported that, "no valid scientific evidence has ever shown that amalgams cause harm to patients" Critics associate long-term exposure to the low levels of mercury vapor with neurodegenerative diseases, birth defects, and mental disorders. Dental offices in California have posted a warning that amalgam contains mercury, "a substance known to cause birth defects and other reproductive harm," since 2003, and a statewide ban on dental amalgam goes into effect in 2006 (Consumers for Dental Choice). There is no debate on the danger of high concentrations of mercury in any form, and both sides agree that amalgam may cause an allergic reaction in mercury-sensitive individuals.

Mercury amalgams have been suspected by some practitioners of integrative or alternative medicine of causing many (often multi-systemic, vague) physical problems. They reason that, since mercury is poisonous, so must be anything containing mercury; hence, amalgams are poisonous. This argument however ignores the difference between a metal and an alloy.

Many of the discussions on this topic have centered, historically, on whether the amalgam mixture is stable, or whether any metals are released from the fillings after being placed in the oral cavity. This focus has in recent years shifted to discussing whether the amount released is significant or not. Some integrative and alternative practitioners claim that it is, while mainstream dental authorities, physicians, and chemists maintain that it is too minuscule to matter.

Various diagnostic methods exist to detect the presence of mercury in the body, including blood tests, urine tests, stool tests, saliva tests, MELISA tests, lymphocyte sensitivity tests, DMPS or DMSA chelation urine tests, a hair analysis and others. Opinions differ on which of these tests, if any, is the best, although mainstream scientific research tends to place the most weight on chelation urine tests or stool tests when trying to assess chronic levels, or on blood or urine tests when trying to assess recent acute exposure. None of these tests, however, can be linked specifically to mercury of dental origin, except (a) on an epidemiological scale; or (b) through measuring levels before and after dental work. Studies have been attempted to investigate both angles, and results have differed, again fueling the controversy on both sides, since the scientific data remains inconclusive and cannot prove either safety or danger.

Nevertheless, alternative practitioners, in some cases with tests and in others without, sometimes recommend their patients to consider removing their dental fillings, saying they suspect mercury poisoning from them.

Some dentists point out that while there is no denying that, when placing the fillings, both patient and dentist are exposed to a small amount of mercury and mercury vapor, once the alloy has hardened (which takes less than a minute), the mercury is captured in the filling and cannot get out, it is bound in the alloy.

Conventional authorities maintain that no medical research has yet provided any conclusive evidence of significant physical problems caused by amalgam fillings. Legal bodies such as 'Consumers for Dental Choice', however, claim to have over 60,000 valid studies on file implicating amalgam fillings in diverse health conditions, which have been used in various lawsuits, and which were the main contributing factor to the bill passed in California in 2002 illegalising amalgam fillings from 2007. Critics have described some of these studies as scientifically invalid. The most recent meta-study has concluded that after studies with methodological flaws are discounted, the evidence indicates that amalgam should not be used.

Posted by Staff at May 18, 2005 2:14 AM

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