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are likely to include variants that contribute to  to replace amalgam fillings with less toxic   Mercury
            susceptibility.  Candidate genes are involved  alternatives must evaluate dentists’ use of ad-
                        7
            not only in methylation and detoxification, but  equate protective measures. The International   levels in
            in vitamin and mineral (i.e., enzyme cofactor)  Academy of Oral Medicine and Toxicology  amniotic
            absorption, transport and metabolism. Unfor-  (IAOMT), a professional dental organization,   fluid, cord
            tunately, policy makers, health authorities and  has developed a protocol and training program
            the dental industry have yet to consider the issue  that attempts to minimize the exposure to mer-  blood,
            of genetic susceptibility. Indeed, for millions of  cury vapor to the patient, dentist and staff during  placental
            children and adults covered by subsidized dental  amalgam removal. In women of childbearing   tissue and
            programs (including military family dental care  age, removal of amalgam should be timed so
            and Native American services), amalgam is still  as to avoid the twelve to eighteen months pre-  breast
            virtually the only option for dental restorations.  ceding conception as well as pregnancy and  milk are

               In 2009, despite much scientific evidence to  breastfeeding.                    significantly
            the contrary, the U.S. Food and Drug Admin-
            istration (FDA) reiterated the safety of dental  DIETARY FISH                      associated
            amalgam. As of 2016, public interest groups   Natural releases of mercury from the  in a dose-
            are challenging this “final amalgam rule” in  Earth’s crust and the oceans account for 60 to 70   dependent
            federal court. Issues to be litigated include  percent of the annual releases of mercury to the
            whether amalgam is deemed an implant, which  atmosphere. The remaining 30 to 40 percent is   manner with
            would require manufacturers to provide proof  attributable to human activities.  Once released  the number
                                                                                7
            of safety, and whether the toxicity warnings that  into the atmosphere through either natural or hu-  of maternal
            are given to dentists via labeling requirements  man activities, mercury is deposited in soil and
            should also be given to patients. Norway, Den-  water, where it enters the food chain. Mercury   dental
            mark and Sweden have banned dental amalgam,  accumulates in fish, particularly large, long- amalgam
            and as of May 2015, a scientific committee of  lived ocean fish.                   fillings.
            the European Commission recommends that      Mercury levels in fish vary widely by
            non-mercury alternatives be used in fillings for  species and by individual, ranging from less
            pregnant women and children.              than 0.1 part per million (ppm) for salmon and
                                      20
               In fact, fetal neurons are more sensitive to  sardines to more than 1 ppm for some samples
            the toxic effects of mercury than any other cell  of tilefish, shark, swordfish and king mack-
            type.  Mercury from the mother’s body readily  erel. A typical 3.5-ounce (one-hundred-gram)
                7
            crosses the placenta and accumulates in the  serving of fish could contain anywhere from a
            fetus, as revealed in postmortem human and  few to more than one hundred micrograms of
            animal studies.  In tissue culture, clear effects  mercury. Tuna contains moderate levels, which
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            on nerve growth arise at mercury concentra-  vary by species. The FDA sets an action level
            tions equivalent to those found in newborns  for mercury contamination in commercial fish
            of amalgam-bearing mothers with no other  of 1 ppm. This means that federal officials are
            known exposures.  Furthermore, mercury levels  allowed to confiscate products that exceed this
                           7
            in amniotic fluid, cord blood, placental tissue  threshold—but it does not mean that they actu-
            and breast milk are significantly associated in  ally do so.
            a dose-dependent manner with the number of   Due to natural releases of mercury, hu-
            maternal dental amalgam fillings.  Human  mans have always encountered some mercury
                                          7,21
            and animal studies show increased rates of  in certain fish. As long as the body’s natural
            miscarriage, neonatal death, low birth weight  defense systems are working, one can con-
            and developmental disorders associated with  sume mercury-containing fish in moderation.
            mercury exposure.                         In healthy individuals, intestinal metallothio-
                            7
               As if the cumulative effects of ongoing  neins (a class of metal-storage molecules that
            amalgam exposure were not enough, unsafe  can be cumulatively damaged by mercury) can
            amalgam removal also can cause acute expo-  sequester ingested mercury and slowly allow
            sures to mercury vapor. Thus, patients wishing  its excretion. Selenium, discussed below, also

            SPRING 2018                              Wise Traditions                                                   17
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