As almost everyone knows by now, the Mad Hatter's odd conception of time (as well as his other idiosyncrasies) was a direct result of his occupation. In the 19th century, hat makers used to treat felt and fur hats with a mercury compound that killed bacteria, thus keeping them from rotting. Hatters used mercury, because it was a potent poison. Not only does it kill bacteria in hats, when inhaled or taken in through the skin, it has a particular affinity for brain tissue. The damage it does to brain cells can be devastating and irreparable.
Symptoms of Mercury Toxicity
Today we know that hatters became "mad" from breathing mercury fumes and getting mercury on their hands. "Mad Hatter's disease," or erythism, is now a recognized psychiatric syndrome consisting of a wide range of neurologic and psychiatric disturbances (see box).1
Chemists classify mercury as a heavy metal. As a rule, heavy metals have no place in the human body; even small amounts can be extremely toxic and difficult to get rid of. Health problems caused by low-level chronic exposure to heavy metals may take years to appear. By the time symptoms occur, it may be too late to do anything about them.
Another heavy metal that has caused - and continues to cause - enormous human suffering all over the world is lead. Until fairly recently, lead poisoning was endemic in the United States, affecting nearly one child in 6, at least to some degree, according to US Public Health Service estimates. Even though things have improved in the last 20 years, thanks to the phasing out of leaded gasoline and lead-based paints, lead poisoning continues to be a real threat, especially to children living in cities and/or buildings with old lead-based plumbing and old (pre-1978) paint jobs. Some of the clinical effects of lead poisoning are shown in the box.
Symptoms of Lead Poisoning
MERCURY POISONING: YOU DON'T HAVE TO BE A HATTER
It's rare that people get exposed to the kind of toxic doses of mercury that occurred in the newly industrializing world of the 19th century, but it still does happen, and usually with tragic consequences. In the 1950s, in the most notorious case of mass mercury poisoning ever, an industrial plant near Minamata, Japan released large amounts of methyl mercury into Minamata Bay. Picked up by the plankton, the mercury moved up the food chain from fish to humans. Even the local cats were affected. When the residents of Minamata unknowingly fed the contaminated fish to their children (and their pets), the result was a devastating syndrome of severe nervous system damage, stunted mental development, blindness, paralysis, and death that nearly wiped out an entire generation.2
Since then, instances of large-scale mercury poisoning have also occurred in Japan, Iraq, Pakistan, and Guatemala. As recently as 1993, the town of Surabaya in East Java suffered hundreds of cases of "Minamata disease" due to chemical waste dumped upstream into the Surabaya River.
While disasters on this scale are, fortunately, rare and isolated, we still need to stay alert. Just a couple of years ago, a beauty cream made in Mexico ("Crema de Belleza-Manning") was associated with at least three cases of mercury poisoning in California, Texas, and New Mexico. Among the cream's ingredients was calomel (aka, mercurous chloride), containing 6 to 8% mercury by weight. The victims, aged 15, 33, and 35 years, suffered symptoms such as fatigue, weakness, insomnia, headache, numbness, irritability, and memory loss.3 Similar mental and physical effects have been observed in people exposed to low levels of mercury vapor.4,5
Because it's so easy to absorb mercury compounds through the skin, their use in cosmetics has been restricted - but not completely eliminated. Women who use eye makeup may not be able to avoid low-level mercury exposure if they use common commercial products. It seems that nothing else works quite as well as mercury as a preservative in some cosmetics, so the FDA, in its wisdom, permits a small, supposedly safe, amount of mercury - 65 parts per million (ppm) - in eye makeup.3
THE DENTAL DILEMMA
It may well be that virtually everyone who has ever had a tooth filled may be continually exposing themselves to low levels of mercury. The standard amalgam tooth filling that dentists have been packing into people's teeth for decades weighs about 1.5 to 2 g and consist of 50% elemental mercury, 35% silver, 13% tin, 2% copper, and traces of zinc. Thus, every filled tooth is a little reservoir from which mercury vaporizes and leaches out over the course of a lifetime. It has been estimated that, depending on how many fillings you have in your mouth, you may be exposed to 10 to 100 µg of mercury every day of your life, just from your teeth.
Can even this minuscule level of exposure cause problems? The answers are less than clear. Some studies indicate potentially serious consequences, especially in children, while others suggest little or no adverse effects.
An analysis of intra-oral mercury vapor found that those subjects with dental amalgams had nine times greater basal levels of mercury vapor than control subjects without amalgams. Chewing was found to stimulate mercury concentration sixfold, which amounted to a 54-fold increase compared with controls. Moreover, mercury levels remained elevated after 30 minutes of continuous chewing and declined slowly over 90 minutes after cessation of chewing. The authors calculated that all subjects were receiving an average daily dose of about 20 µg, with the exposure increasing according to the number of amalgams. In some participants, the mercury exposure from dental amalgams was 18 times higher than the allowable daily limits set by some countries for exposure to all sources.6,7
In a Canadian study, amalgam fillings containing a radioactive tracer were placed in the teeth of laboratory monkeys. Within 4 weeks, traces of the radioactive mercury were found in high concentrations in various organs and tissues, with the highest levels in the kidney, GI tract, and jaw. Radioactive mercury amalgam placed in the teeth of pregnant sheep quickly found its way into the fetus. Mercury in the mother's milk could also be ingested by the newborn lamb.8
A small European study using a standardized personality inventory did find an effect, though. The researchers compared 29 15-year-olds with no fillings to 41 15-year-olds with fillings, and found that the kids with fillings were more prone to suffer from muscle tension and anxiety.9
In a US study, 25 women with amalgam fillings and 23 with no amalgams were given a standard personality test, the "Beck Depression Inventory." The women with fillings were found to have an increased risk of depression, as well as significantly greater tendency to express anger without provocation and to experience more intense angry feelings. The women with amalgam fillings also scored poorly on other behavioral measures: compared to their counterparts, they were more anxious, less pleasant, less happy, less secure, less steady, and had a harder time making decisions.10
The patient in the dental chair is not the only one potentially at risk from mercury poisoning. Dentists and their assistants may also be in danger. A study compared behavioral test scores in dentists exposed to elemental mercury and those not so exposed. The exposed dentists, who had significantly higher urinary mercury levels, also showed significant deficits in mental concentration, emotional instability, somatosensory irritation, and mood. The authors suggested that the accumulated test scores provided "evidence of subtle preclinical changes in behavior associated with Hg [mercury] exposure."11
While amalgam fillings are used less and less these days, the problem still arises: what to do with existing fillings. Should you have them drilled out and replaced with apparently safer composite materials? The process of removal, aside from being costly and unpleasant, may expose you to more mercury than if you just left them alone. One option is to not disturb your fillings and capture any mercury released by the process of chelation. We'll talk more about this important option later on.
LEAD POISONING: NO LEVEL IS SAFE
Lead can produce adverse effects, not only on mental function, but on virtually every system of the body. Like mercury, lead holds the greatest danger for fetuses and young children, who absorb it more readily and whose developing nervous systems are exceptionally vulnerable.
The harm that lead causes may be directly related to the amount present in the body; no level, no matter how low, can be considered "safe." Blood levels of lead as low as 10 µg/dL have been associated with harmful effects on children's learning and behavior. Higher levels sustained over a period of months or years may have dire consequences for a child's mental and physical health.
As noted above, much has been done to reduce environmental lead during the last two decades, but lead still remains a threat to millions. In 1989, a report in the AMA publication American Medical News12 stated that about 4 million children and 400,000 fetuses were being exposed to levels of lead high enough to cause convulsions, brain damage, coma, and death. Lesser exposure was associated with low birth weight, impaired hearing and cognitive development, and reduced IQ.
According to other estimates from the Environmental Protection Agency (EPA) and the Department of Health and Human Services, as many as 10% of preschoolers may be affected. A large 1991 epidemiologic survey (Third National Health and Nutrition Examination Survey, NHANES III) found that over the previous 20 years, the average child's blood-lead level decreased from 12.8 to 2.8 µg/dL. That's the good news. At the same time, though NHANES III indicated that about 1.7 million US children under the age of 6 still had blood levels above the Center for Disease Control's "safe" level, <10 µg/dL.13
According to the CDC's estimate, every 10-µg increase may cause an irreversible drop of 1 to 3 IQ points.14 In fact, the AMA report stated, "Exposure levels which were considered harmless are now thought to cause numerous health problems."12
Children living in inner city poverty are certainly the most vulnerable to lead poisoning, but better socioeconomic conditions are no guarantee of protection. The CDC found that, while 22% of black children and 16.4% of poor children living in older housing had levels of lead 310 µg/dL in their blood, elevated levels were found in 890,000 children, or 4.4% of all children.15
Any children living in homes built - or painted - prior to 1978 are at greatest risk to lead exposure from lead-based paint chips and dust. According to government estimates, 83% of privately owned housing units built in the US prior to 1980 - about 64 million homes - contain some lead-based paint. Lead is also found in drinking water, especially in cities with old, lead pipe-based plumbing systems or houses with pipes held together by lead solder. In Roxbury, Massachusetts, near Boston, for example, it has been estimated that 40% of the population is affected by lead poisoning. The source is the 100-year-old water system combined with the area's highly acidic water supply that easily dissolves the lead from the plumbing into the drinking water.16
A recently revealed source of lead contamination that appeared in many unsuspecting middle-class homes was a type of inexpensive vinyl window mini-blinds imported from Asia or Mexico. Lead was added to the vinyl to help stabilize it, but unfortunately, over time the plastic deteriorates from exposure to sunlight and heat, forming lead dust on the surface of the blind that young children could easily ingest.17 Public playground equipment, in which the old lead paint is chipping or peeling off, represents another recently discovered potential lead poisoning hazard for young children.18
Other potential sources of lead poisoning include old bathtubs covered with lead-based glaze, lead crystal glasses, decanters, and pitchers, antique furniture and toys painted with lead-based paint, printed materials like newspapers and magazines containing lead-based inks, and imported china and ceramics. Even though lead has been gone from gasoline for many years, decades of lead fumes may have seeped into soil near roads. Thus, it's best to avoid soil and dust or dirt gathered near heavily traveled roads. Even fresh fruits and vegetables should be suspect if they were grown in soil near these roads or near lead-emitting industries.
GETTING THE LEAD - AND MERCURY - OUT
The best way to avoid the dangers of heavy metal poisoning, of course, is to minimize exposure. Considerable public health efforts are expended daily to encourage parents to remove this threat from their children's lives. Recommended steps for reducing lead exposure include:
The most important source of mercury poisoning for most people on a daily basis is dental amalgam. You can reduce your exposure by requesting that your dentist use only composite filling materials that contain no mercury or other heavy metals. As for old fillings, as discussed earlier, having them removed may be more problematic than leaving them in, especially if you have a lot of them. In that case, the best solution may be to protect yourself with regular chelation.
THE CHELATION SOLUTION
Chelation is a process by which a molecule binds with, or chelates, certain minerals that are present in the bloodstream and then removes them from the body, usually via the urinary system. For more than half a century, chelation has been recognized - even by the FDA - as a safe and extremely effective means of removing heavy metal contamination from the body. The chelating substance used most often is a synthetic amino acid, ethylene diamine tetraacetic acid (EDTA).
During the 1940s, EDTA chelation was routinely used to treat workers in battery factories or those working with lead-based paints. While the use of EDTA chelation for treating occlusive vascular disease continues to be highly controversial in this country, intravenous (IV) EDTA remains the recommended treatment of choice for individuals whose blood levels of lead, mercury, or other toxic heavy metals are dangerously high.19 Used properly, IV EDTA chelation has been shown to be extremely safe and effective for removing high levels of heavy metals from the body.
It may be, in at least some instances, that heavy metal poisoning and vascular disease are connected. A case was reported in the medical literature in which a 51-year-old man, who had been hypertensive since he was a teenager, was treated with IV EDTA chelation. His physician noticed that a large amount of lead (a five-fold increase) was appearing in the man's urine after each treatment, suggesting he had very high levels of lead in his system. This finding was of particular interest, because previously published reports had linked high lead levels to hypertension. Thus, it was gratifying that, once the lead was removed from his system, his blood pressure returned to normal and, for the first time since he was 18, he did not require antihypertensive medication.20
But what if your levels of lead or mercury have not reached the acutely dangerous range? What if you're still concerned about chronic low-level exposure, such as from environmental pollution, dental fillings, or other sources? Is a series of IV chelation treatments your only option?
Fortunately, there is a simple, convenient, and inexpensive solution. Developed by Garry Gordon, MD, the "Father of Chelation Therapy," chelation capsules combine two powerful chelating agents in an oral form.
If you're concerned about how much heavy metal you may be absorbing into your system, Dr. Gordon recommends oral chelation as the ideal solution for dealing with low-level, chronic exposure to heavy metal contamination. You can not only get the proven power of oral EDTA, but garlic, too, which has been shown to increase the fecal excretion of mercury by as much as 400% and to completely protect blood cells against high levels of lead.18 If, for example, you were constantly absorbing tiny amounts of mercury from your old dental fillings, what could be easier than taking a few capsules each day to soak them up like a sponge around a leaky faucet?
As a bonus, you may also be helping your heart and vascular system. Although the American medical establishment is loathe to admit it, chelation therapy has been shown to work wonders with arteries clogged by atherosclerotic plaque. Even if you currently have no symptoms of heart disease, taking oral chelation capsules to control possible heavy metal poisoning may also help keep your arteries clear.