* According to the occupational health and safety textbooks on dental personnel mercury poisoning is a common finding. In addition, a number of investigators have linked occupational mercury exposure to infertility and birth defects in dental personnel. One dentist as you may recall sued her dental school when she gave birth to an infant with acrodynia (mercury poisoning in children). Apparently, no professor had mentioned during her 4 years of training that her infant could be poisoned in the womb if mercury vapor is inhaled. Kidney function in dental workers is also impaired. I could go on at length. This entire lecture along with appropriate references is available if you would like. Ask for Toxics in Dentistry dkennedy@ucsd.edu

*From: dkennedy@UCSD.edu (Dr D. Kennedy)

" Dental Educator, D.D.S., M.S.D. says:

The controversy you refer to exists only in the minds of many subscribed to this listserver whose main arguments depend on studies that are considered flawed by most ethical researchers or on anecdotal information that cannot be reproduced in scientific studies. "

It seem that all dentists can do is denigrate the published scientific research of others rather than examine the question with valid scientific markers. There are no flaws in the research only unanswered questions. For example; do sheep chew more often than gum chewing teenagers and night bruxers. and Do monkeys fed twice a day chew more than most humans?

THERE IS NO CONTROVERSY THAT MERCURY FROM AMALGAM CONSTUTUTES THE LARGEST

SOURCE OF MERCURY EXPOSURE IN THE HUMAN POPULATION.

World Health Organization Figures

(World Health Organization, Environmental Health Criteria 118: Inorganic Mercury, Geneva, 1991.)

The World Health Organization has calculated the average human daily dose of mercury from various sources is:

Dental amalgam = 3.0-17.0µg/day (Hg vapor)

Fish and Seafood = 2.3 µg/day (methylmercury)

Other food = 0.3 µg/day(inorganic Hg)

Air & Water = Negligible traces

The WHO document further states that "A specific no-observed--effect level (NOEL) cannot be established." That is, any amount causes some damage.

Stock's Classic Mercury Breath Experiment

Dr. Stock blew his own breath into an empty leather bag. He then distilled it through newly blown glasswear and produced a tiny droplet of mercury. This drop he measured with a calibrated microscope. Used calculus to calculate the concentration in the bag and performed chemical analysis to make certain that the shimmering silver droplet was in fact mercury. He showed that his breath contained 10 micrograms of mercury per cubic meter (ug/m3).

What was wrong with that experiment? Nothing! Dr. Stocks work was replicated in 1981 by the late Dr. Carl Svare. (Svare CW, Peterson LC, Reinhardt JW, Frank CW, Boyer DB: Dental Amalgam: a potential source of mercury vapor exposure. J Dent Res 59(special issue A):34l, Abstract #293, 1980) It has since been replicated over 10 times by other investigators and has even been used as a subject for student science fairs. This is a perfect example of a widely taught anecdotal opinion's triumph over published science. The dentists who served on the ADA panel in 1931 apparently never even attempted to replicate Dr. Stocks experiments. They just canonized their agust opinions into dental dogma and spread the word that Dr. Stock was a flawed researcher.

Now that his research has been thoroughly vindicated, who was this Dr. Stock? He was the director of the Kaiser Wilhelm Institute in Germany and one of the leading scientists of his time. So you see, even great scientists can be denigrated by the spin doctors.

Danger To Dental Workers

Many dentists have claimed that dental amalgam is safe because the amount released into ones breath does not exceed the OSHA Maximum Allowable Concentration (MAC) of 100 micrograms/per cubic meter (ug/m3) and most people do not continuously exceed the Time Weighted Average (TWA) of 50 ug/m3. What they fail to explain to their patients is that workers exposed to any portion of the OSHA TWA and MAC are subject to medical monitoring for mercury poisoning and written informed consent from their employer. The medical records must remain on file for thirty years after termination of exposure. (Do any dental schools in the world comply with this regulation?) These standards are based upon adult physiology and we know that some adults will become highly poisoned at these levels. Dental students are not employees. Their health is protected by the EPA. Later Dental Educator remarks on the high level of mercury a patient is exposed to during removal. All dental students working in closed tiny laboratories without the benefits of respirators and vacuum hoods are illegally exposed to high levels of mercury vapor.

Children, Infants, the general public and especially pregnant women are specifically excluded from the OSHA standard. Their health is protected by the Environmental Protection Agency (EPA). The EPA has documented an infant poisoned at 2 ug/m3 and has a current standard of 0.3 ug/m3. Few if any people who have occlusal amalgam fillings breath is below this standard, but wait there is more.

Studies of dentists have found memory loss and hand dexterity problems from occupational exposure. This is predictable considering the blatant attitude toward personnel exposure and carless handling of mercury compounds demonstrated by dental educators. On the other hand the US Public Health Service Agency for Toxic Substances and Disease Registry (ATSDR) has just recommended new standards for the acute exposure to mercury that make it impossible to even mix the components of the filling together much less pack and carve. They determined in November of 1994 that a transient exposure to .020 (ug/m3) was an acute exposure. That means that this level was immediately hazardous to health.

Also make sure to read these books: Poison in Your Teeth: Mercury Amalgam (Silver) Fillings...Hazardous to Your Health! and Mercury Detoxification by Tom McGuire