Ben Thurman MD

Why are heavy metals toxic and how humans are exposed to heavy metals in the environment?

Chelation therapy is performed to remove heavy metal toxins from the body. Heavy metals are some of the most ubiquitous of environmental toxins and by far some of the most destructive to our health for a number of reasons. Anything organic, e.g. wood, coal, paper, petroleum fuels, etc that are combusted, liberate heavy metals into the atmosphere. These settle in the soil, lakes, rivers, and streams and get integrated into the water table and crops that grow on the land. Animals that eat these grain crops get heavy metals in their tissue. Humans eat these heavy metal contaminated food sources and the toxins are concentrated in us.

People in larger cities also breathe a lot of volatile metals from the air as pollutants from industry and automotive sources. Metal pipes and fittings are sources of heavy metal in drinking water. Agriculture uses many chemicals such as fungicides, herbicides, defoliants, and pesticides that contain heavy metals as a coordinating structure for the organic chemicals that surround them. Metals are in the building and house dust that we breathe as well as some of the older paints and metal finish material for anti-rust purposes. In addition many fabrics that are flame retardant have heavy metals as part of their chemical structure. Many industrial chemicals and solvents contain heavy metals that enter the body through unprotected skin as well as inhalation.

More insidious but equally harmful sources of heavy metals, mercury in particular, come from dental amalgam fillings, which on average are about 50% mercury, usually about 25% is silver, with the remaining 25% an amalgamation (hence the name mercury amalgam) of copper, zinc, tin, and other metals. I am often asked why dentists put such toxic metal in the mouth and I'm hard pressed to explain it. If you look at the amalgam container in a dentist's office, the manufacturer's label displays a skull and crossbones. To me, that indicates poison, but maybe dentists who use mercury amalgams have forgotten the meaning of that symbol. The amalgam is placed in the teeth and while in the mouth it magically is safe. Upon removal, however dentists are breaking the law if they pitch the filling over into the trash can. Since 1988, the EPA ruled that dental amalgam mercury is too toxic to put in landfill. So, let's see, it's toxic before going in the mouth, toxic when it comes out, but while in your mouth it's just fine.

In 1981, Dr Carl Svere, a dentist on the faculty of the Ohio State Dental School got hold of a mercury vapor analyzer. Recall President Nixon in the early '70s created EPA to monitor and report environmental pollution. During that time an instrument was created to measure ambient mercury vapor in the air in certain factories that used mercury in the production process. Readings of excessive mercury in the air of such factories could result in substantial fines and factory shut down until the pollution problem was resolved. To Dr. Svere's horror, he discovered that mercury vapor readings from the exhaled breath of his students with mercury dental fillings exceeded, in some cases substantially, the upper limits of what was acceptable to EPA standards of mercury safety. When he later reported these potentially explosive findings in a peer-reviewed dental journal, he was met with a deafening silence.

One Canadian dentist, Murray Vimy, on the faculty of the University of Calgary was intrigued, however, and he teamed with a PhD fetal physiology researcher at the university, Fritz Lorscheider, to study if the exhaled mercury vapor was re-breathed. If it was, they wanted to know to where in the body it redistributed and in what amounts. They used a sheep model because sheep are basically chewing machines - if no problem was found in sheep, it would be a waste of time to experiment on primates. Ingeniously, Vimy and Lorscheider used pregnant sheep since they wanted to know if dental amalgam mercury distributed from mother's fillings to the fetal brain. I will not bore you with details, but the fillings placed in mother sheep mouths were radio labeled, i.e. the radioactive mercury could be tracked if it spread from mother's teeth to her other tissues and fetus. The results stunned them showing radioactive mercury ending up all through the mother's digestive tract and liver, the kidneys, the brain and locally all through the sinuses. More importantly high concentrations of mercury distributed to the fetal brain. Their studies were reported in stages through the mid to late 80s. It had only a small impact on the dental community, with an embarrassingly tiny handful of dentists alarmed at the danger. It was an uphill battle.

By the early 90s, a protein chemist named Boyd Haley began to study mercury toxicity on nerve cells and brain tissue. Dr Haley is renowned for his pioneering research in phosphorescent photo affinity labeling of proteins within cells. So far, mercury was proven to be highly unstable in that it was both soluble and therefore swallowed as well as volatile and therefore breathed into the lungs and absorbed across the alveolar-capillary membrane. From there as shown by Vimy and Lorscheider, mercury circulated to all vital organs including placenta and fetal brain. Soluble mercury that is swallowed with water and food is very toxic to the good lactic acid fermenting bacteria and yeast and they are quickly killed off. In their place, pathogenic bacteria are able to fill the niche since they can survive the mercury better and thrive in a more alkaline gut environment. To get back to Dr Haley's research which spanned the entire decade of the 90s, he published paper after paper in peer reviewed journals of toxicology and biochemistry demonstrating that mercury is very toxic to nerve cells by inhibition of key enzymes in concentrations as low as 1-3 parts per billion. The toxicity increased one thousand fold when just one other metal, such as aluminum was introduced.

Other researchers demonstrated that mercury also tracks into the brain via olfactory nerves in the sinuses. The nerves have a conveyor belt system of microtubular proteins that carry mercury directly from the sinus into the brain. Over time mercury inhibits the polymerase enzyme that links subunits of a protein called tubulin together and this disables the conveyor belt. About this time another extremely intriguing series of experiments were answering a question that had stumped neurotoxicologists and pathologists for some time. Why, it was being asked, did autopsied brains of apparently normal people have in some cases 2-3 times more mercury in their brain and yet other brains from patients the same age showed normal, sometimes less than normal mercury levels and yet they had devastating brain diseases such as Parkinson's and Alzheimer's? The reason for this made it clear that some people genetically are pre-disposed to make less of a protective mercury binding protein and are therefore much more neurologically vulnerable to only a tiny amount of environmental mercury. Scientists now suspicion that the devastating autism epidemic has arisen from the ramped up vaccination schedule since 1992 with more vaccines containing an extremely toxic ethyl-mercury derivative called Thimerosal.

Everyone is familiar with potential mercury exposure from fish. Few people realize that even flu-shots contain Thimerosal. One study has shown an alarming increase in dementia among elderly patients who take annual flu shots compared to those the same age that who do not.

Entire toxicology books have been written on heavy metals, so you can see I have barely introduced the subject, but you now know more about mercury toxicity then the next two hundred doctors and dentists you meet combined. None of what I've told you and certainly not any of what I'm about to say was taught in my medical school or post-graduate medical training.

Now that we've touched on environmental sources of heavy metals, let's look at their chemistry and bio-chemistry in order to understand how, once they get in out tissue, they can be removed safely and effectively.

But first, more about heavy metal toxicity: The heavy metal toxins of greatest clinical significance are mercury, cadmium, lead, arsenic, tin, silver, antimony, nickel, and aluminum. Obviously even physiologically vital metals like iron, zinc, copper and manganese can be toxic when accumulated to excess. Some people for example, are familiar with a disease entity called hemochromatosis, a genetically determined pathology engendered by increased iron binding proteins in the gut cell lining which leads to excessive iron storage toxicity in the liver, pancreas and brain. The toxic metals have a high affinity for sulfur and much of metal ore refining is an effort to separate metals from sulfur. When these metals accumulate in the body, they typically ionize by losing an electron and become positively charged. In this state they readily seek sulfur again, so it is not surprising that we find them bound to both sulfated amino sugars that are the backbone of glycosaminoglycans and sulfated structural alpha-helical proteins which together form the extra-cellular scaffolds and matrix among which cells of the various organs and glands are supported. Time was when this network was largely ignored as inert connective tissue, but research starting from Alfred Pischinger's group in Austria from the 60s-80s has astonished us with the amazing properties of what he refers to as the ground regulation system. Without getting overly technical, due to the gel-sol phase transitions possible within this tissue matrix, our organs are basically embedded in a liquid/solid state crystalline voltage regulated or gated semi-conductor. Those of you who are computer savvy know exactly that I speak of an almost unlimited information storage capacity and tuner amplifier organ that interlaces and weaves through every fiber of our body. Naturally when heavy metals get entrapped within this net, not to mention other toxins such as chemicals, microbial ferments, and cellular waste products that are unsuccessfully disposed of, when these toxins foul up the mesh, the molecular array is distorted, the electronics are out of tune and healthy vibrations give way to a list of dissonant vibrations which express themselves in enough various ways to fill a textbook of pathology. Are you beginning to see the importance of getting this toxic trash out of our structural - information-energy network? This salutary effect of heavy metal detox is amplified by subtle vibrational therapies that resonate with a healthy well-aligned and well tuned connective tissue network. We have even learned through recent research in molecular biology that the network of structural proteins is continuous and cooperates with intra-cellular cyto-architecture. This miraculous web of energy and information is constantly eaves-dropping and responding to our thoughts. But I digress. In addition to polluting the extracellular matrix, heavy metals do other nasty things to reinforce their toxicity. I mentioned Dr. Haley's work with mercury and its role in blocking the cellular enzymes of nerve and other cells. Toxic metals bind to the catalytic site, the business end of an enzyme, often crowding out the normal physiological mineral from that space and thereby render the enzyme inoperable. When metals bind to receptor sites of signaling proteins, they can down regulate or up-regulate the signal causing abnormal cell responses which then make cells more vulnerable to other toxins, microbes, or cell death due to overstimulation- this last pathway, also called excitotoxicity is the focus of much current research. As if this isn't enough heavy metals, when bound to molecular networks, especially in the neighborhood of the cell membrane, change not only the function of proteins, but also their appearance. This is important because a subset of lymphocytes called T-8 or cyto-toxic lymphocytes are tasked with tracking the appearance of cellular structures in order to identify and eliminate foreign debris or cells. This is the basis of organ graft rejection. You can also easily see how some types of auto-immune phenomena arise from heavy metal distortions of cell architecture leading to immuno-confusion where the body attacks itself. Please understand, the body does not just stupidly wake up one day and decide to attack itself. Rather, the immune response is activated because something foreign (i.e. toxic) is in the tissue and needs to be dealt with. Aluminum, being a metal with a plus three valence is a special case because it loves to bind phosphorus and phosphorus is particularly concentrated in the phospholipids of the myelinated nerves. Aluminum binding to these parts of the nerve fibers is tantamount to having a rat chewing on an electrical cord. I know by now you are thinking, enough already, but I could not discuss heavy metal toxicity without at least a mention of free radical stress and oxidative destruction of tissue, i.e. when oxidation is excessive organs and tissue age at an accelerated rate. Oxidation promoted by heavy metals occurs because transition element metal chemistry makes them unable to hold on to outer shell electrons. When they lose these electrons good or bad things, depending on your perspective, can happen. If you want to speed up or catalyze a chemical reaction metals can be useful for industry, e.g. the nickel catalyst used in hydrogenation of unsaturated fats creating evil trans-fats. On the other hand, if you are not a catalytic chemist, excessive electron loss from heavy metal toxins can render oxygen containing species toxic (i.e. oxidized) because oxygen loves to grab these errant electron bullets. Oxygen is over energized or juiced in this state and becomes hyperactive or tissue destructive. Under controlled circumstances of the leukocyte oxidative burst these oxygen radicals help us by killing microbes. Also understand that mono-atomic oxygen awaits two protons and two electrons at the end of every mitochondrial electron transport chain - Absent this we cannot make ATP, the energy medium or dollar currency of the cell. Bottom line, we need oxidation for life. Heavy metals promote unwanted, unregulated excessive oxidation which leads to tissue destruction and rapid aging.