paragraph_text: Research in the field of nutrition has greatly contributed in finding out the essential facts about how environmental depletion can lead to crucial nutrition-related health problems like contamination, spread of contagious diseases, malnutrition, etc. Moreover, environmental contamination due to discharge of agricultural as well as industrial chemicals like organocholrines, heavy metal, and radionucleotides may adversely affect the human and the ecosystem as a whole. As far as safety of the human health is concerned, then these environmental contaminants can reduce people's nutritional status and health. This could directly or indirectly cause drastic changes in their diet habits. Hence, food-based remedial as well as preventive strategies are essential to address global issues like hunger and malnutrition and to enable the susceptible people to adapt themselves to all these environmental as well as socio-economic alterations.

paragraph_text: The Beutong mine is a large copper mine located in the west of Indonesia in Sumatra. Beutong represents one of the largest copper reserve in Indonesia and in the world having estimated reserves of 505 million tonnes of ore grading 0.59% copper, 2.1 million oz of gold and 20 million oz of silver.

paragraph_text: Iron is usually found as iron ore on Earth, except for one deposit of native iron in Greenland, which was used by the Inuit people. Native copper, however, was found worldwide, along with silver, gold and platinum, which were also used to make tools, jewelry, and other objects since Neolithic times. Copper was the hardest of these metals, and the most widely distributed. It became one of the most important metals to the ancients. Eventually, humans learned to smelt metals such as copper and tin from ore, and, around 2500 BC, began alloying the two metals to form bronze, which is much harder than its ingredients. Tin was rare, however, being found mostly in Great Britain. In the Middle East, people began alloying copper with zinc to form brass. Ancient civilizations took into account the mixture and the various properties it produced, such as hardness, toughness and melting point, under various conditions of temperature and work hardening, developing much of the information contained in modern alloy phase diagrams. Arrowheads from the Chinese Qin dynasty (around 200 BC) were often constructed with a hard bronze-head, but a softer bronze-tang, combining the alloys to prevent both dulling and breaking during use.

paragraph_text: Conventional bleaching of wood pulp using elemental chlorine produces and releases into the environment large amounts of chlorinated organic compounds, including chlorinated dioxins. Dioxins are recognized as a persistent environmental pollutant, regulated internationally by the Stockholm Convention on Persistent Organic Pollutants. Dioxins are highly toxic, and health effects on humans include reproductive, developmental, immune and hormonal problems. They are known to be carcinogenic. Over 90% of human exposure is through food, primarily meat, dairy, fish and shellfish, as dioxins accumulate in the food chain in the fatty tissue of animals.

paragraph_text: Radioactive ores were first extracted at Radium Hill in 1906, and Mount Painter in South Australia in the 1930s, to recover radium for medical use. Several hundred kilograms of uranium were also produced. Of the world's proven estimated uranium reserves (5,404,000 tonnes), 31% are held in Australia (1,673,000 tonnes), ahead of the second largest, Kazakhstan (12.1% or 651,800 tonnes). In terms of production, Canada is the largest supplier to export markets, followed by Kazakhstan and Australia. Uranium mined in Australia is mainly for export. Australia exported 50,235 tonnes of uranium oxide concentrate in the five years to 2008, worth A $2.9 billion.

paragraph_text: The was one of the largest copper, lead and zinc mines in Japan. The mine is located in Tōhoku region of northern Japan in the town of Kosaka, Akita Prefecture. The mine had reserves amounting to 30 million tonnes of ore grading 2.84% lead, 8.48% zinc, 1.1 million oz of gold and 177.3 million oz of silver.

paragraph_text: The Phu Kham mine is a large copper mine located in the south of Laos in Savannakhet Province. Phu Kham represents one of the largest copper reserve in Laos and in the world having estimated reserves of 450 million tonnes of ore grading 0.54% copper, 3.46 million oz of gold and 30.2 million oz of silver.

paragraph_text: In 1609, he invented the "pan amalgamation" process (in Spanish the "cazo" or "fondo" process) for extracting silver from ore by mixing it with salt and mercury and heating it in shallow copper vessels. In 1640 he published in Madrid a book entitled "Arte de los Metales", the earliest work on South American ores and minerals. It includes information on mineral localities in Bolivia. The book has been republished in Spanish, French and English.

paragraph_text: In several countries, reductions in the use of some vaccines were followed by increases in the diseases' morbidity and mortality. According to the Centers for Disease Control and Prevention, continued high levels of vaccine coverage are necessary to prevent resurgence of diseases that have been nearly eliminated. Pertussis remains a major health problem in developing countries, where mass vaccination is not practiced; the World Health Organization estimates it caused 294,000 deaths in 2002.

paragraph_text: In 1862, paper money was issued without the backing of precious metals, due to the Civil War. Silver and gold coins continued to be issued and in 1878 the link between paper money and coins was reinstated. This disconnection from gold and silver backing also occurred during the War of 1812. The use of paper money not backed by precious metals had also occurred under the Articles of Confederation from 1777 to 1788. With no solid backing and being easily counterfeited, the continentals quickly lost their value, giving rise to the phrase "not worth a continental". This was a primary reason for the "No state shall... make any thing but gold and silver coin a tender in payment of debts" clause in article 1, section 10 of the United States Constitution.

paragraph_text: Uranium ore is mined in several ways: by open pit, underground, in-situ leaching, and borehole mining (see uranium mining). Low-grade uranium ore mined typically contains 0.01 to 0.25% uranium oxides. Extensive measures must be employed to extract the metal from its ore. High-grade ores found in Athabasca Basin deposits in Saskatchewan, Canada can contain up to 23% uranium oxides on average. Uranium ore is crushed and rendered into a fine powder and then leached with either an acid or alkali. The leachate is subjected to one of several sequences of precipitation, solvent extraction, and ion exchange. The resulting mixture, called yellowcake, contains at least 75% uranium oxides U3O8. Yellowcake is then calcined to remove impurities from the milling process before refining and conversion.

paragraph_text: Zinc metal is produced using extractive metallurgy. After grinding the ore, froth flotation, which selectively separates minerals from gangue by taking advantage of differences in their hydrophobicity, is used to get an ore concentrate. This concentrate consists of about 50% zinc with the rest being sulfur (32%), iron (13%), and SiO
2 (5%). The composition of this is normally zinc sulfide (80% to 85%), iron sulfide (7.0% to 12%), lead sulfide (3.0% to 5.0%) silica (2.5% to 3.5%), and cadmium sulfide (0.35% to 0.41%).

paragraph_text: Many ancient civilizations alloyed metals for purely aesthetic purposes. In ancient Egypt and Mycenae, gold was often alloyed with copper to produce red-gold, or iron to produce a bright burgundy-gold. Gold was often found alloyed with silver or other metals to produce various types of colored gold. These metals were also used to strengthen each other, for more practical purposes. Copper was often added to silver to make sterling silver, increasing its strength for use in dishes, silverware, and other practical items. Quite often, precious metals were alloyed with less valuable substances as a means to deceive buyers. Around 250 BC, Archimedes was commissioned by the king to find a way to check the purity of the gold in a crown, leading to the famous bath-house shouting of "Eureka!" upon the discovery of Archimedes' principle.

paragraph_text: Sandra Steingraber (born 1959) is an American biologist, author, and cancer survivor. Steingraber writes and lectures on the environmental factors that contribute to reproductive health problems and environmental links to cancer.

paragraph_text: Mercury has been smelted from cinnabar for thousands of years. Mercury dissolves many metals, such as gold, silver, and tin, to form amalgams (an alloy in a soft paste, or liquid form at ambient temperature). Amalgams have been used since 200 BC in China for plating objects with precious metals, called gilding, such as armor and mirrors. The ancient Romans often used mercury-tin amalgams for gilding their armor. The amalgam was applied as a paste and then heated until the mercury vaporized, leaving the gold, silver, or tin behind. Mercury was often used in mining, to extract precious metals like gold and silver from their ores.

paragraph_text: Material: First place (the Gold medal): It is composed of silver of at least. 925 grade, plated with 6 grams of gold. Second place (the Silver medal):. 925 silver. Third place (the Bronze medal): It is 97.0% copper with 0.5% tin and 2.5% zinc; the metal value was about US $3 in 2010.

paragraph_text: Small-scale artisanal mining of gold is another source of dangerous child labour in poor rural areas in certain parts of the world. This form of mining uses labour-intensive and low-tech methods. It is informal sector of the economy. Human Rights Watch group estimates that about 12 percent of global gold production comes from artisanal mines. In west Africa, in countries such as Mali - the third largest exporter of gold in Africa - between 20,000 and 40,000 children work in artisanal mining. Locally known as orpaillage, children as young as 6 years old work with their families. These children and families suffer chronic exposure to toxic chemicals including mercury, and do hazardous work such as digging shafts and working underground, pulling up, carrying and crushing the ore. The poor work practices harm the long term health of children, as well as release hundreds of tons of mercury every year into local rivers, ground water and lakes. Gold is important to the economy of Mali and Ghana. For Mali, it is the second largest earner of its export revenue. For many poor families with children, it is the primary and sometimes the only source of income.

paragraph_text: In the United States, the EPA serves as an advisory organ to set the levels of mercury that are non-fatal in humans. Symptoms of exposure to high levels of methyl mercury include disturbed vision, hearing, and speech, lack of coordination, and muscle weakness. Medical studies have examined the correlation of fish consumption and health issues. American studies have presented evidence of fish consumption and its effects on child development. Longitudinal studies agree that human activities are what release and accumulate mercury in marine life. Addressing the issues of fish consumption forces health officials to recognize the sources of mercury in the human body. Specific Native American tribes are vulnerable to a high exposure of mercury. Studies have determined that these native peoples in the United States suffer more from mercury poisoning and illness than any other cohort group in the country. This is due to the fact that fish is a main source of protein. Exposure risk was assessed through a medical study, thus raising judicial issues of whether the public health of these groups is a priority in the United States.

paragraph_text: The use of uranium in its natural oxide form dates back to at least the year 79 CE, when it was used to add a yellow color to ceramic glazes. Yellow glass with 1% uranium oxide was found in a Roman villa on Cape Posillipo in the Bay of Naples, Italy, by R. T. Gunther of the University of Oxford in 1912. Starting in the late Middle Ages, pitchblende was extracted from the Habsburg silver mines in Joachimsthal, Bohemia (now Jáchymov in the Czech Republic), and was used as a coloring agent in the local glassmaking industry. In the early 19th century, the world's only known sources of uranium ore were these mines.

paragraph_text: Zinc is a chemical element with symbol Zn and atomic number 30. It is the first element of group 12 of the periodic table. In some respects zinc is chemically similar to magnesium: its ion is of similar size and its only common oxidation state is +2. Zinc is the 24th most abundant element in Earth's crust and has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest mineable amounts are found in Australia, Asia, and the United States. Zinc production includes froth flotation of the ore, roasting, and final extraction using electricity (electrowinning).

Question: What human health problems has the substance used to extract gold and silver from their ores been directly linked to?
Answer: disturbed vision, hearing, and speech, lack of coordination, and muscle weakness