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By depleting ergy savings offered by CFLs, which include Nutrition and Physical Degeneration, whose
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glutathione reduced mercury emissions from coal-fired ideas Chris Masterjohn subsequently developed
power plants, make them desirable (a debate that in his research on fat-soluble vitamins; in Sally
and is beyond the scope of this article). Fallon Morell’s and Thomas Cowan’s Nourish-
disabling the Finally, significant sources of local ex- ing Traditions Book of Baby and Child Care;
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glutathione- posure to mercury may include incinerators, and in the more epigenetically focused Deep
coal-fired power plants, crematoria and other Nutrition by Catherine and Luke Shanahan.
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related industrial processes. For over a decade, the EPA
enzymes, has attempted to restrict mercury emissions MERCURY AS ANTINUTRIENT
mercury from U.S. coal plants by about 90 percent, but Mercury readily binds to sulfhydryl, a type
the rule is under litigation, and legal experts of sulfur also called a thiol. The thiol is the major
impairs the predict that enforcement is years away. In some reactive site within the amino acid, cysteine,
detoxification countries, gold mining techniques that employ which is ubiquitous in biochemically active
of many mercury remain a significant source of exposure proteins such as enzymes. The human body
for miners and local populations. U.S. miners contains tens of thousands of enzymes, which
toxicants, used these techniques during the Gold Rush. drive most fundamental biological processes.
ironically Mercury also binds strongly to selenium,
including DEVELOPMENTAL AND a cofactor for several dozen enzymes involved
in vital tasks such as thyroid function and brain
EPIGENETIC TOXICITY
mercury The developmental period from conception antioxidant protection. Although said to protect
itself. through early childhood is a window of vulner- against mercury toxicity, selenium’s protective
ability in which both epigenetic and neurological scope is limited by its intracellular availabil-
damage can occur at exposures far lower than ity. This is governed by kidney processes that
those known to cause toxicity in adults. Epi- limit the amount of such minerals in the blood-
genetics refers to the alteration of gene expres- stream and by specialized channels within the
sion (turning genes on and off)—usually via cell membrane that control mineral transport
environmental factors—without alteration of from the bloodstream into cells. Lipophilic
the DNA nucleotide sequence itself, in a manner mercury, on the other hand, has no such limits
that can be passed to offspring. when entering cells. Moreover, mercury can
Mercury is a potent epigenetic toxicant of block selenoprotein P, a substance that stores
alarming scope, with both direct and indirect and transports selenium to cells. Therefore,
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effects on gene expression. Mercury directly selenium offers only limited protection against
targets the cysteine that comprises the DNA- mercury exposure.
binding sites on most gene transcription fac- The body’s most important intracellular an-
tors. In addition, it targets the cysteine in DNA tioxidant mechanism is the glutathione system.
methyltransferase enzymes, which play a role Glutathione detoxifies mercury by binding it (in
(DNA methylation) in normal gene expression. a process called glutathione conjugation) into a
Indirectly, mercury promotes severe oxidative less toxic form suitable for excretion through the
stress. Early-life stressors are known to induce bile. The glutathione system has been found to
changes in gene expression that set the stage be crucial in the detoxification of thimerosal.
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for disease in later life. Thus, unfortunately, However, because the glutathione molecule and
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exposure to mercury in either parent, even prior its related enzymes employ cysteine, they also
to conception, can affect the child’s own genetic are targets for mercury. Mercury can damage the
expression. body’s glutathione system both by depleting the
Epigenetic damage may range from mild glutathione molecule itself and by blocking the
to severe, and the resulting phenotype may enzymes that synthesize and recycle glutathione
include characteristics such as dental defor- and facilitate its use. By depleting glutathione
mities, myopia, asymmetries of the face and and disabling the glutathione-related enzymes,
disproportions of the body. Such characteristics mercury impairs the detoxification of many
are described in Weston A. Price’s pioneering toxicants, ironically including mercury itself,
20 Wise Traditions SPRING 2018