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Many commonly used substances like  and fertility problems. These toxic effects have   Mercury
            ethanol (alcoholic beverages), herbicides and  been documented by the U.S. Department of
            even saunas can cause birth defects. Viral in-  Health and Human Services’ Agency for Toxic   is one of
            fections, radiation, drugs, maternal disease or  Substances and Disease Registry (ATSDR). The   the most
            metabolic conditions (diabetes, hypothyroid),  extreme toxicity of mercury can be seen from   insidious and
            heavy metals in the environment, malnutrition  documented effects on wildlife at very low lev-
            or nutrient deficiencies and goitrogens can also  els of exposure. Because of its extreme toxicity,   dangerous
            be major factors.                         only one-half gram of mercury is required to   teratogens on
                          3
                Mercury (Hg) is a major teratogen, consid-  contaminate the ecosystem and fish of a ten-acre   earth because
            ered one of the most toxic substances on earth  lake to the extent that a health warning would
            and a serious global pollutant. Natural emissions  be issued by the government not to eat the fish. 5  it has ready
            of mercury into the air and water occur from     Mercury is one of the most insidious and   access to the
            volcanic eruptions, through weathering of rocks,  dangerous teratogens on earth because it has   human body
            degassing of the earth’s crust and evaporation  ready access to the human body even before
            of water. Man-made sources of mercury include  birth, while the baby is in utero. The unborn   even before
            industrial pollution, burning fossil fuels (the  are most at risk from the effects of mercury.   birth, while
            largest source of pollution), mining (gold, sil-  It can be inhaled, passed through the skin or   the baby is
            ver), refuse incineration, cremation and factory  ingested. Mercury exposure even once during a
            production. Mercury is no longer mined in the  pregnancy can cause harm to the unborn child’s   in utero.
            U.S.—most mercury today comes from mines in  body and mind, while continued exposure
            Spain, China, Kyrgyzstan and Algeria. Mercury  causes increasingly serious defects. 5
            is often used in gold mining, and many small
            operators in Africa use children to separate out  FISH CONSUMPTION
            the gold. Paints and building materials such as     The Food and Drug Administration (FDA)
            roofing shingles contain mercury, which can be  and Environmental Protection Agency (EPA)
            released during use and disposal. Fossil fuel-  recommend that women who are pregnant,
            burning power plants are the largest source of  breastfeeding or plan on becoming pregnant;
            mercury pollution.                        women of childbearing age; and children con-
                            4
                Researchers have positively identified vari-  sume more fish—two to three servings (eight
            ous teratogens through observation, anecdotal  to twelve ounces) from the “Best Choices” list
            evidence, animal studies and examination of  or one serving from the “Good Choices”—but
            human exposures. Studies on animals have  avoid seven specific fish highest in mercury.
            found mercury to be extremely cytotoxic, neu-  They say that children should eat one to two
            rotoxic, immunotoxic and genotoxic; it is also  seafood meals per week starting at age two.
            an endocrine disrupter and a cause of infertility  The 2017 FDA chart “Advice about Eating Fish”



                                              FORMS AND SOURCES OF MERCURY
                Mercury is a heavy metal that occurs in several basic forms: organic methylmercury (MeHg) and ethylmercury (EtHg),
             and inorganic (metallic or elemental) mercury. Organic mercury is the most dangerous form of mercury to human health. 6
                Historically, most of the research and concern regarding mercury’s toxic effects on humans and in particular on fetal
             development has focused on MeHg, which is considered one of the six most dangerous chemicals in the environment.
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             MeHg can easily cross into the brain and body organs and is also extremely neurotoxic, much more so than inorganic
             forms. MeHg is better absorbed and shows a higher mobility in the human body than inorganic mercury. Ethylmercury is
             present in thiomersal, which has been used as a major preservative in vaccines.  Today it is still in use in the flu vaccines
                                                                               8
             recommended for pregnant women and children older than six months of age. 9
                MeHg is found mainly through food, especially fish ingestion, although industrial pollution is also a dangerous source.
             Mass poisonings affected many in Iraq when people consumed bread made from seeds sprayed with mercury. There have
             been highly publicized major acute poisonings affecting many people and infants exposed through eating fish in Japan
             at Minamata Bay in 1956. The Minamata disaster was caused by release of MeHg into the bay by the Chisso Chemical
             Corporation. 10

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