Heavy Metals and Disease
Minerals like magnesium, calcium, iron, manganese, copper and zinc are involved in many biochemical reactions in the body, usually as cofactors for enzymatic reactions (in which one chemical is transformed into another). These minerals are generally “good” in a biochemical sense, with the partial exceptions of iron and copper which can, in some individuals, become problematic in excessive quantity.
Other minerals like lead, mercury, cadmium, aluminum, arsenic, tin, among others (”heavy metals”) are known to produce health problems. These occur either because these heavy metals compete with the “good” minerals, and interfere with enzymatic reactions necessary for health, or because they bind to various proteins or membranes in the body and interfere with normal function.
This has a lot of clinical relevance.
Lead, for example, has been shown to lower IQ (reversibly), raise blood pressure and increase the risk of heart attack, to mention only three impacts on well-being. Cadmium (on which I cut my teeth as a researcher years ago) is associated with lung, kidney, nerve and blood vessel disease. Mercury also has many well-documented adverse health impacts (amalgam fillings have been illegal for dental use in much of Europe since 1994), but remains controversial in this county largely due to the political efforts of the American Dental Association, which has major conflicts of interest. Mercury has been shown to cause disease in virtually every organ in the body, but is especially toxic to the nervous system, the heart, kidneys, liver and endocrine glands, as well as energy production within the cell. Arsenic is famous as a poison (e.g., the play Arsenic and Old Lace), but in lesser doses interferes with energy production and causes certain types of cancer.
There is no safe level of any of the toxic heavy metals.
The federal government’s NHANES study showed many Americans carrying significant body burdens of toxic heavy metals. Not everyone with a body burden of toxic heavy metal is sick from that metal. Some are, some are not. Disease caused by metals cannot always be reversed by removal of the offending metal, but a majority of people in various clinical studies have been improved in varying degree. The technology for removing toxic metals from the body has been well worked out over the past fifty years or so, and can be done safely under established protocols, when indicated.
Selected References:
- Ibrahim D, Froberg B, Wolf A, et al. Heavy Metal Poisoning: Clinical presentations and pathophysiology. Clin Lab Med 2006; 26:67-97.
- Monnet-Tschudi F, Zurich MG, Boschat C, et al. Involvement of environmental mercury and lead in the etiology of neurodegenerative diseases. Rev Environ Health 2006; 21(2): 105-17.
- Houston MD. The role of mercury and cadmium heavy metals in vascular disease, hypertension, coronary heart disease and myocardial infarction. Altern Ther Health Med 2007; 13(2):S128-33.
- Kern JK, et al. Sulfhydryl-reactive metals in autism. J Toxicol Environ Health A 2007; 70(8):715-21.
- Soden SE, et al. 24 hour provoked urine excretion test for heavy metals in children with autism and typically developing controls, a pilot study. Clin Toxicol (Phila) 2007; 45(5):476-81.
- Exley C, et al. Non-invasive therapy to reduce the body burden of aluminum in Alzheimer’s disease. J Alzheimers Dis 2006; 10(1):17-24; discussion 29-31
- Hyman MH. The impact of mercury on human health and the environment. Altern Ther Health Med. 2004; 10(6):70-75
- http://www.epa.gov/waterscience/fishadvice/advice.html
- Monnet-Tschudi F, Zurich MG, Boschat C, et al. Involvement of environmental mercury and lead in the etiology of neurodegenerative diseases. Rev Environ Health 2006; 21(2): 105-17.
- Suzuki T, Takemoto TI, Kashiwazaki H, et al. Metabolic fate of ethylmercury salts in man and animal. In: Miller MW, Clarkson TW Ieds) Mercury, Mercurials, and Mercaptans. Springfield: Charles C Thomas, 1973:209-233,
- Nash D, Magder L, Lustberg M, et al. Blood lead, blood pressure, and hypertension in
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- Menke A, Muntner P, Batuman V, et al. Blood lead below 0.48 micromoles per liter (10 micrograms per deciliter) and mortality among US adults. Circulation 2006; 114:1388-1394.
- Nawrot T, Staessen J. Low level environmental exposure to lead unmasked as silent killer. Circulation 2006; 114:1347-1349.
- Clarkson TW, Magos L, Myers GJ. The toxicology of mercury—current exposures and clinical manifestations. N Engl J Med. 2003;349(18):1731-1737.
- Shubert J, Riley E, Tyler S. Combined effects in toxicology – a rapid systemic testing procedure: Cadmium, Mercury and Lead. J Toxicology and Environmental Health 1978;4:763
- Fernandez N, Beiras R. Combined Toxicity of Dissolved Mercury with Copper, Lead and Cadmium on Embryogenesis. Ecotoxicology 2001;10(5):263-271.
- Stratton K, Gable A, McCormick MD, et al. Immunization Safety Review, Institute of Medicine, National Academy Press, Washington, DC, 2001.
- Bernard S, Enayati A, Redwood L, et al. Autism: a novel form of mercury poisoning. Medical Hypotheses 2001; 56(4):462-471.
- Reus IS, Bando I, Andres D, et al. Relationship between expression of HSP70 and metallothionein and oxidative stress during mercury chloride induced acute liver injury in rats. J Biochem Mol Toxicol. 2003: 17(3): 161-8.
- Guha Mazumder DN, et al. Randomized placebo-controlled trial of 2.3-dimercapto-1-propanesulfonate (DMPS) in therapy of chronic arsenicosis due to drinking arsenic-contaminated water. J Toxicol Clin Toxicol 2001; 39:665-74.