Mercury in your Mouth

“Silver” dental fillings are increasingly recognized as a health risk

by Christine Johnson

Over the last few years, increasing awareness of environmental mercury problems has spurred efforts by various groups to eliminate the use of mercury in products including electrical switches, batteries, and thermometers (see www.mercurypolicy.org for examples). But mercury contamination may be much closer to home than many people think. The World Health Organization (WHO) released a report in 1991 entitled Environmental Health Criteria 118; Inorganic Mercury, which reported that the most significant source of mercury in the general population is actually “silver” dental fillings (see www.bioprobe.com for this and related sources). “Silver” dental fillings, or amalgams, have various compositions, but the most common composition contains approximately 50 percent mercury.

Animal and human studies performed over the last decade have proven that mercury is continually released from the fillings, and that the common perception that the mercury is “locked in the fillings” is a misnomer. The documented range of mercury vapor released from amalgams in the WHO report was 3.9 to 21 micrograms per day. Values were substantially higher for those who chew gum or have dissimilar metals in the mouth.

The Agency for Toxic Substances and Disease Registry (ATSDR) has set a Minimum Risk Level (MRL) for elemental mercury vapor of 0.2 micrograms per cubic meter of air (www.atsdr.cdc.gov/mrls.html). For a respiration rate of 20 cubic meters per day, this amounts to a maximum limit of 4 micrograms per day. This MRL is based upon case studies of poisoning in industrial settings, but it is not clear if this level is appropriate for amalgams which release mercury 24 hours a day, 365 days a year, for years.

In his book Mercury Poisoning from Dental Amalgam, Patrick Stortebecker, M.D.,Ph.D. presents a wide range of medical data concerning poisoning from dental amalgams. One of the more interesting sections recounts the observations of Alfred Stock, a German chemist who studied mercury toxicity from dental amalgams for 20 years starting in 1926. Stock’s observations, while ignored for decades, have largely been verified by modern researchers. He described poisoning symptoms in three stages. The first stage is characterized predominantly by psychiatric symptoms with the addition of fatigue as a significant symptom. The second stage includes extreme fatigue, lack of concentration, impaired memory, moodiness, irritability, headache, and slight tremor. The third stage includes profound fatigue, severe headaches, dizziness, vertigo, tremor, mental incapacity, despondency, increased salivation, and loss of smell, among others.

Long-term exposure to small amounts of mercury results in a condition known as micromercurialism, which can often manifest itself with so many different symptoms that diagnosis is quite difficult. Since the earliest symptoms are psychological in nature, many patients seeking help from doctors are typically sent to psychiatrists or other mental health professionals. In an Alternative Medicine Review article (vol5, no. 2-2000) by Walter Crinnion, N.D, a Kirkland, Washington-based naturopathic doctor, the psychological symptoms of mercury toxicity reported closely match those of Stock’s observations: irritability, excitability, temper outbursts, quarreling, fearfulness/anxiety, restlessness, depression, and insomnia. He also reports that mercury “inhibits the uptake and release of dopamine, serotonin, and norepinephrine.” These neurotransmitters are the target of most anti-depressants, including Prozac, Paxil, and Zoloft.

As damaging as mercury poisoning is to an adult, for the developing fetus it is devastating. In their book Infertility & Birth Defects; Is Mercury From Silver Dental Fillings An Unsuspected Cause? authors Sam Ziff and Dr. Michael F. Ziff review studies which show that mercury passes through the placenta and that fetal mercury levels far exceed those of the mother. Certain stages of fetal development seem to be exquisitely sensitive to the effects of mercury, and this has undoubtedly resulted in a significant number of birth defects.

They also report that the EPA, in a 1984 Mercury Health Effects Update, (EPA-600/8-84-019F) stated that “women chronically exposed to mercury vapor experienced increased frequencies of menstrual disturbances and spontaneous abortions; also, a high mortality rate was observed among infants born to women who displayed symptoms of mercury poisoning.” A recent National Research Council report found that 50 percent of all pregnancies result in prenatal or postnatal mortality, birth defects, or other chronic conditions (www.nap.edu/catalog/9871.html)

Mercury from dental amalgam has been suggested as a primary or aggravating agent in a wide variety of syndromes with an unknown etiology, including Multiple Sclerosis (MS), lupus, cardiovascular disease, Alzheimer’s disease, and a wide variety of psychiatric disorders, including depression and anxiety. A significant number of people have fully recovered or significantly improved after the removal of amalgams. In his book It’s All In Your Head; The Link Between Mercury Amalgams and Illness, Dr. Hal Huggins shares his personal experiences in treating large numbers of people suffering from these syndromes, as well as documenting recoveries after amalgam removal (available at www.hugnet.com)

So what does the American Dental Association (ADA) have to say about all this? Publicly, their position has undergone several changes through the last few decades. In the early 80’s, they said that the mercury is “locked in the fillings” rendering it harmless. After the development of the mercury vapor analyzer, it became clear that this position was not supported by the emerging scientific evidence. The ADA’s position then changed to indicate that some mercury does leak out from the fillings, but that the amount is too small to be of any significance. The WHO, however, has repeatedly stated that there is no amount of mercury which can be considered to have no effect. The ADA has refuted any causal relationship between amalgams and disease, calling the rapidly growing number of recoveries after amalgam removal “anecdotal.”

Of more significance is the statement made by the ADA in legal proceedings. In the Superior Court of the State of California, case number 718228, in a demurrer dated October 22, 1992, the ADA’s lawyers said “The American Dental Association... owes no legal duty of care to protect the public from allegedly dangerous products used by dentists. The ADA did not manufacture, design, supply, or install the mercury-containing amalgams. The ADA does not control those who do. The ADA’s only alleged involvement in the product was to provide information regarding its use. Dissemination of information relating to the practice of dentistry does not create a duty of care to protect the public from potential injury.”

Interestingly, the ADA has recently revised its code of ethics, making it a violation for dentists to recommend replacement of amalgam with other materials. They have opposed informed consent legislation in Illinois and California, and continue to apply their political power to impede efforts to remove mercury from dentistry. In her book The Law and Mercury-Free Dentistry, author Pamela Ousley explores some of the legal challenges that mercury-free dentists face which threaten their professional survival, as well as providing a historical basis for the current legal situation.

If you think you may be suffering from mercury poisoning from dental amalgams, several groups have information as well as providing referrals to health care professionals who are educated on the topic. One such group is a grassroots organization called Dental Amalgam Mercury Syndrome (DAMS). Information from DAMS is available at www.amalgam.org.•