New Natural Approaches to Chelation
With Hurricane Katrina bringing to the forefront the issue of heavy metal and environmental toxins, on-going research and clinical evidence continues to point out the adverse health effects of these toxic substances. This article reviews the topic and suggests natural and safe ways to detoxify/chelate and protect the body from toxic metals.
History and Current Trends of Heavy Metal Toxicity
Heavy metal toxicity has been reported since ancient times with some of the earliest recorded cases of mercury toxicity dating back to ancient Egyptian society. Throughout the ages, various outbreaks of poisonings involving heavy metal toxicity have surfaced, including the use of heavy metals in traditional medicines in the 18th century, mercury toxicity in hat makers, lead toxicity from exposure or ingestion of lead-based paint, pink disease caused by Mercury in teething powder, and most recently the controversies surrounding mercury exposure from fish consumption. Although great steps have been taken to limit the public's exposure to heavy metals (such as reducing lead levels in house paints) there continues to be many points of potential exposure to heavy metals. Moreover, although acute poisonings are well-documented, the effects of long-term, chronic exposure are less known and hard to document or pinpoint.
One of the current public health concerns is the effect of mercury on women of child bearing years and young children. Mercury is the second most common cause of acute heavy metal poisoning, according to the American Association of Poison Control Centers in 1997, and recent warnings of its chronic effects have been issued by the EPA and FDA (Patrick, 2002). In 2004 the Environmental Protection Agency (EPA) issued two press releases warning women of the dangers from eating fish due to toxic mercury content. In a March 2004 Press release, the EPA warned that nearly all fish contain traces of mercury, and some have high enough levels to harm an unborn child or a young child's developing nervous system. They advised limiting fish consumption to two meals a week. Another press release followed in August of 2004 warning that 1/3 of the nation's lakes and 1/4 of its river ways were contaminated with toxic levels of mercury and other pollutants. Another warning was released regarding avoidance of fish consumption from these sources (see EPA and FDA, 2004).
Confirming this message, both the Centers for Disease Control and the Journal of the American Medical Association published studies that showed 8-10% of women of childbearing age harbor toxic levels of mercury. Additionally, a panel of the National Academy of Sciences warned definitively that some of the children born to these mothers were at risk of becoming children "who struggle to keep up in school and who might require remedial classes or special education (see CDC, 1999; Schober et al., 1999)."
Overview of Heavy Metals
"Heavy metals" are chemical elements with a specific gravity that is at least 5 times the specific gravity of water (specific gravity of water=1 at 4°C). Certain heavy metals are nutritionally essential for our health, such as iron, copper, manganese and zinc. However, heavy metals become toxic when they are not metabolized by the body and subsequently accumulate in the soft tissues. There are 23 heavy metals of concern for their toxicity and common exposure (see Table 1).
Table 1. The Heavy Metals of Concern
| antimony |
cobalt |
manganese |
Thallium |
| arsenic |
copper |
mercury |
Tin |
| bismuth |
gallium |
nickel |
Uranium |
| cadmium |
gold |
platinum |
vanadium |
| cerium |
iron |
silver |
Zinc |
| chromium |
lead |
tellurium |
|
As recent controversies focus on both mercury and lead exposure, it is also important to recognize their possible routes of exposure to patients. Lead accounts for most of the cases of pediatric heavy metal poisoning (Roberts, 1999). However, this may be changing with ongoing toxic levels of mercury in the food chain, and our greater understanding of its effects. Lead is a very soft metal and was used in pipes, drains, and soldering materials for many years. Millions of homes built before 1940 still contain lead (e.g., in painted surfaces), leading to chronic exposure from weathering, flaking, chalking, and dust. Industrial production of lead goes to manufacture batteries, cable coverings, plumbing, ammunition, and fuel additives. Other uses are as paint pigments and in PVC plastics, x-ray shielding, crystal glass production, pencils, and pesticides. Target organs are the bones, brain, blood, kidneys, and thyroid gland.
Mercury is the heavy metal that has the widest distribution in our environment. It is generated naturally in the environment from degassing of the earth's crust and volcanic emissions. It also is released from industrial pollution, and is present in many products that we might be exposed to daily, such as batteries, thermometers, and in foods like fish. Mercury exists in three forms: elemental, organic and inorganic mercury. Mining operations, chloralkali plants, and paper industries are significant producers of mercury that contribute to industrial pollution (Goyer 1996). Atmospheric mercury is wind dispersed across the globe by and returns to the earth in rainfall where it accumulates in aquatic food chains (Clarkson 1990). Mercury compounds were added to paint as a fungicide until 1990 and it continues to be used in thermometers, thermostats, and dental amalgam. Medicines containing mercury, such as mercurochrome and merthiolate, are still available. Algaecides and childhood vaccines are also potential sources. Target organs are the brain and kidneys (Roberts 1999; ASTDR ToxFAQs? for Mercury).
Symptoms & Diagnosis
The symptoms of heavy metal toxicity depend on the metal-sometimes also the chemical species-and the route of exposure. Symptoms are wide ranging for each group of heavy metals, as well as for one specific metal, and are therefore easy to misdiagnose. For example, mercury toxicity affects multiple organ systems and may mimic several diseases. Some of the signs and symptoms include mental disturbance, including insomnia, shyness, memory loss, emotional instability, depression, anorexia, disturbances in the functioning of blood vessels, excess perspiration, blushing, headache, visual disturbances, peripheral neuropathy, salivation, insomnia, and ataxia. Along with the signs and symptoms, the tests for determining the heavy metal load in the body also depend on the type of metal. For a more complete review see the references: Diner and Brenner, 2004; Clarkson et al., 2003; and Patrick, 2002, or visit the website: www.dreliaz.com.
Conventional Treatments vs. Emerging Natural Approaches
Chelation is the process of chemically binding metals and other toxins. Chelation with standard pharmaceutical agents is performed for acute cases and carries the risk of dangerous side effects from the removal of essential nutrients and metals from the body.
The well-known chelation agents are dimercaptosuccinic acid (DMSA), DMPS (Dimercaptopropane Sulfonate) and ethylene diaminetetraacetic acid (EDTA). They are usually administered intravenously and attach to toxins with ionic bonds. Once bonded, the chelation agent will then carry the toxin out of the body. However, since it is usually bonded in only one way, sometimes the toxin is able to react with other cells in the body. Chelation agents may cause serious side effects because they are not exclusively preferential to the toxins, but will bind to other metals in the system as well as calcium, and essential trace minerals.
Alternative treatments for chelation and detoxification are showing a great deal of promise, as they are both effective and free from major side effects.
Low Molecular Weight Pectins and Alginates
Recently, a type of modified citrus pectin (MCP) known as PectaSolŽ (a dietary supplement mostly known for its use in inhibiting cancer metastasis, and reducing tumor growth and development) was identified for its ability to chelate and cleanse the body of mercury (El-Zoghbi and Sitohy, 2001).
In a recent clinical study, MCP was administered to a group of patients, and baseline levels of their total mercury body burden were taken and then compared against levels after treatment with 15 grams of PectaSolŽ daily for four to ten months. The total mercury body burden for each individual was determined for baseline measurements using DMPS (2,3-Dimercapto-1-propanesulfonic acid) challenge of 250 mg i.v., followed by 6 hours of urine collection. The results showed a significant average decrease of over 60% (p=0.03) in the total body mercury burden after treatment with MCP (Eliaz, 2004).
In an earlier study, MCP (PectaSolŽ) was given to patients and shown to increase urinary secretion of heavy metals such as lead, mercury, cadmium and arsenic. The results of the study found that MCP's gentle nature allowed for safe chelation with no side effects. It was suggested to be a promising alternative to the harsher intravenous chelating therapies currently offered as primary therapy for heavy metal toxicity (Eliaz and Rode, 2003).
MCP may be more effective when combined with alginates for gentle chelation. Alginates have also been found to remove heavy metals from the body. They do this by passively binding to heavy metals and sequestering them in an alginate biomass, which then pass out of the body in normal excretory processes. Of the many types of substances that have been tested for their ability to absorb heavy metals, low molecular weight alginates have performed well showing the ability to bind heavy metals, such as mercury, lead, copper, cadmium, and zinc (Davis et al., 2003; Kim et al., 2005; Carr et al., 1968; Korotaev et al., 1992; Sutton et al., 1972; Sutton et al., 1971). Alginates can also bind to heavy metals, especially mercury and lead in the digestive tract. This is of great importance as it can prevent absorption of heavy metals newly digested and can prevent re absorption of heavy metals secreted into the gut through the bile.
Herbs and Other Supplements
Other herbs and supplements have shown the ability to support natural detoxification processes in the body. Alpha-lipoic acid is a well known antioxidant, but it can also negate the effects of several toxic metals. One study specifically focused on the regeneration ability of two different alpha-lipoic acid regimens to improve the condition of neurotoxicity caused by mercury exposure. Glutathione status in individuals has also been found to be an important factor in protecting against the toxic effects of certain metals, such as mercury, lead, iron and cadmium. Additionally, glutathione is known to play a role in immune system and liver function (Patrick, 2002).
Vitamin C can also help reduce the effects of certain toxic heavy metals (Cai et al., 2001; Dhir et al., 1993; Dhir et al., 1990; Vij et al., 1998). Vitamin E is another antioxidant that can protect the lungs from toxins. Studies have shown that vitamin E has a protective effect on tissues from necrosis caused by several other heavy metals, such as cadmium, zinc and cobalt (Tandon et al., 1992; Van Vleet et al., 1981).
Certain herbs that have traditional uses for "blood purification" or detoxification are also showing promise. Cilantro has been found to be able to eliminate mercury deposits in humans. It has been found to increase the efficacy of antibiotic drugs in certain infections that might have a mercury toxicity component and accelerate the elimination of certain metals, such as mercury, lead and aluminum in the urine (Omura and Beckman, 1995). Preliminary research has also shown Chlorella (an algae) may have the ability to detoxify the body of mercury deposits, especially the removal of dental amalgam (Hagino and Ichimura, 1975; Horikoshi et al., 1979).
Importance of Mercury Detoxification in Two Stages
As the accumulation of heavy metals did not happen overnight, it is wise to not remove them overnight. It is important to follow a two-stage detoxification procedure so that chelated heavy metals do not react or get re-deposited to other tissues of the body during the process. As harsher pharmaceutical chelation agents have the ability to remove mercury from the brain, they can also have the ability to aid in the penetration of mercury into these same tissues. However, if chelation is performed over a longer period of time (1-6 months) with a gentle chelating agent, such as MCP and alginates, they may slowly reduce the heavy metal burden on the tissues.
In the second stage, nutrients high in sulfured amino acids or supplements of sulfured amino acids-such as Garlic, Cystein, Methoinine, NAC and MSM-can be used together with botanicals that facilitate the binding of heavy metals in the tissues (Cilantro as an example), and nutrients that can cross the blood brain barrier to help in the elimination of mercury. These nutrients include alpha lipoic Acid, L-Carnitine and others. Such a system enhances the chelation process utilizing botanicals that promote elimination and discharge while supporting the various detoxification systems of the body. They can also help in mitigating the effects of mercury toxicity.
An important auxiliary step is to maintain a healthy gut function and healthy bacterial flora. This can be done by supporting both the prebiotic phase as well as the probiotic phase and supporting healthy digestive function. Digestion and elimination requires energy or "heat." Detoxification is usually a cooling process. Therefore, it is important to make sure that the vitality of the body and especially the digestive and urinary systems are supported in the process. For more information, see: www.DrEliaz.com.
We cannot prevent exposure to mercury, but we can prevent the absorption of it into our systems through gentle chelation. Using healthy and natural dietary supplements, it is possible over time reduce our body burden of the toxic metals that have a tendency to accumulate and causing more serious acute and chronic diseases.
References:
ATSDR ToxFAQs? for Mercury. Agency for Toxic Substances and Disease Registry. http://www.atsdr.cdc.gov/tfacts46.html
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Clarkson, T.W., Magos, L., Myers, G.J. (2003) The toxicology of mercury- current exposures and clinical manifestations. The New England Journal of Medicine. 349:1231-7.
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