Encyclopedia of Global Resources part 10 potx

Argentina’s natural gas and petroleum exports are relatively important to the region, but Venezuela and Bolivia exceed Argentina by far in terms of totals for both resources in productio

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The Country

Argentina is a wedge-shaped country at the tip of

South America Physically, the nation has the largest

territory and fourth largest population—after

Mex-ico, Colombia, and Spain—of all Spanish-speaking

countries in the world In total area, it is four times the

size of Texas and is the eighth largest country in the

world Its capital, Buenos Aires, is the largest city in

the Southern Cone, which includes Argentina, Chile,

Paraguay, and Uruguay Argentina’s annual gross

do-mestic product is consistently second in South

Amer-ica Brazil, the largest country in the region, is always

first Argentina clearly has great wealth and greater

economic potential owing to its natural resource base

However, the top 1 percent of the people have nearly

all of the wealth and the bulk of the land, and the

national debt is high Additionally, growing crops for

export and simultaneously producing food crops for

domestic consumption constitute a challenge for

Ar-gentina As world food prices have escalated, export

critics have worried about Argentina’s ability to feed

its own people at affordable prices Thus, Argentina

has natural resource problems for which the

coun-try’s diverse and educated people must eventually

find solutions

Agricultural Land of the Pampas

Agricultural land composes 47 percent of Argentina’s

total area, and agricultural products account for about

one-half the annual value of the country’s exports to

the global economy The bulk of Argentina’s

agricul-tural exports come from the Pampas, which is the

wealthiest rural area in South America The region’s

vast, open plains, deep, rich soil, and moderate

cli-mate are the physical bases for the wealth The plains

topography is conducive to raising large fields of

fod-der crops for livestock yards and for open field

graz-ing The climate of the Pampas area is much like that

of the Middle Atlantic states of the East Coast of the

United States The Pampas has year-round

precipita-tion, a relatively long growing season, and mild winter

temperatures The region’s best-known agricultural

exports are hides (for leather), beef, wool, and wheat

However, its two most valuable commodities are

ani-mal feed (including unmilled cereals) and vegetable

fats, oils, and oil seeds, which come mostly from

soy-beans and sunflower seeds Argentina’s main trading

partners for these products are China, India, Brazil,

and Chile

In addition to the land’s natural resources, outside

influences were important in the development of Ar-gentina’s export trade During the late 1800’s, in addi-tion to capital and business methods, the British trans-planted technology that was especially suitable to the Pampas’ windswept, grassy plains; the windmill and barbed wire spurred the grazing and breeding of high-quality beef cattle Additionally, the British and other foreign interests introduced refrigeration tech-nology, an efficient railroad network, seaport facilities

in Buenos Aires, and swift iron-hulled ships As a re-sult, Argentina was one of the leading agricultural ex-porters in the world by the close of the nineteenth century

In the twenty-first century, the country ranks among the top-ten exporters in more than one dozen agricul-tural categories The “Wet Pampa,” the more humid eastern part of the region, is more productive than the “Dry Pampa” to the west The Wet Pampa pro-duces most of the nation’s exports, serving as the gra-nary of South America, with soybeans, alfalfa, corn, sunflowers, and flax as the principal crops Neverthe-less, experts have expressed concern about degrada-tion of the soil in the Wet Pampa because of overuse and abuse The main crop in the Dry Pampa is wheat Cattle and sheep ranches exist throughout the Pam-pas, especially in the southeast and north The region produces most of the beef and mutton that are ex-ported from the country Dairy products and vegeta-bles, which are destined primarily for Argentine con-sumers, are important near Buenos Aires

Agricultural Land of the Interior Argentines often describe their population as

com-posed of two groups, porteños and people of the inte-rior Porteños live in greater Buenos Aires, which

corre-sponds to the city of Buenos Aires and its intertwining connections of highways, railroads, and cities in the Pampas region People of the interior live outside the Pampas and are much more rural in their outlook and economy

The climate and soils of Argentina’s interior lands vary from humid tropical and subtropical to desert and mountain The Paraná Plateau, which is north of Buenos Aires, is the warmest and wettest part of the country Coffee, tea, and yerba maté, a popular variety

of tea in Argentina and adjoining areas, are the re-gion’s chief export crops

The Mesopotamia lowland is just west of the pla-teau, where the Paraná and Uruguay rivers flow paral-lel to each other The lowland has a subtropical

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cli-Argentina: Resources at a Glance

Official name: Argentine Republic Government: Republic

Capital city: Buenos Aires Area: 1,073,596 mi2; 2,780,400 km2

Population (2009 est.): 40,913,584 Language: Spanish

Monetary unit: Argentine peso (ARS)

Economic summary:

GDP composition by sector (2008 est.): agriculture, 9.9%; industry, 32.7%; services, 57.4%

Natural resources: fertile plains of the Pampas, lead, zinc, tin, copper, iron ore, manganese, petroleum, uranium,

boron, bauxite, precious metals, lithium

Land use (2005): arable land, 10.03%; permanent crops, 0.36%; other, 89.61%

Industries: food processing, motor vehicles, consumer durables, textiles, chemicals and petrochemicals, printing,

metallurgy, steel

Agricultural products: sunflower seeds, lemons, soybeans, grapes, corn, tobacco, peanuts, tea, wheat, livestock

Exports (2008 est.): $70.59 billion

Commodities exported: soybeans and derivatives, petroleum and gas, boron, vehicles, corn, wheat

Imports (2008 est.): $54.55 billion

Commodities imported: machinery, motor vehicles, petroleum and natural gas, organic chemicals, plastics

Labor force (2008 est.): 16.27 million (urban areas only)

Labor force by occupation (2008 est.): agriculture, 1%; industry, 23%; services, 76%

Energy resources:

Electricity production (2006 est.): 109.4 billion kWh

Electricity consumption (2006 est.): 97.72 billion kWh

Electricity exports (2007 est.): 2.628 billion kWh

Electricity imports (2007 est.): 10.27 billion kWh

Natural gas production (2007 est.): 44.8 billion m3

Natural gas consumption (2007 est.): 44.1 billion m3

Natural gas exports (2007 est.): 2.6 billion m3

Natural gas imports (2007 est.): 1.9 billion m3

Natural gas proved reserves ( Jan 2008 est.): 446 billion m3

Oil production (2007 est.): 790,800 bbl/day Oil imports (2005): 23,380 bbl/day Oil proved reserves ( Jan 2008 est.): 2.186 billion bbl

Source: Data from The World Factbook 2009 Washington, D.C.: Central Intelligence Agency, 2009.

Notes: Data are the most recent tracked by the CIA Values are given in U.S dollars Abbreviations: bbl/day = barrels per day;

GDP = gross domestic product; km 2 = square kilometers; kWh = kilowatt-hours; m 3 = cubic meters; mi 2 = square miles.

Buenos Aires

Argentina

Bolivia

Brazil Chile

Paraguay Uruguay

Falkland Islands

A t l a n t i c

O c e a n

P a c i f i c

O c e a n

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mate and exports spices (pepper, cumin, turmeric,

nutmeg, cinnamon, and ginger), tobacco, citrus, and

cattle

The semiarid Gran Chaco, which sits immediately

west of Mesopotamia, exports some live cattle, cotton,

and oil crops, especially peanuts and sunflower seeds

Still farther west is the Dry Chaco, which is truly a

desert because it is in the rain shadow of high summits

of the Andes Mountains Nevertheless, the Gran

Chaco’s fertile valley oases in the states of Jujuy, Salta,

Tucumán, San Juan, and Mendoza export several

products, including sugar, grape juice, fruits, and

corn Wine from these valleys, in particular, has gained

popularity in the U.S market Livestock husbandry,

especially of cattle and sheep, has been important

also

Patagonia is the final agricultural region that

con-tributes to the nation’s export economy Sheep

ranch-ing (chiefly for wool) is a principal product of the

re-gion The poor soils of Patagonia and its cool and dry

climate limit crop production

Petroleum and Natural Gas

Oil and petroleum-related products and natural gas

make up Argentina’s second most valuable category

of exports Together, they amount to about 15

per-cent of the total value of the country’s exports The

main recipients are Chile, the United States, Brazil,

and China, in that order Most of Argentina’s

produc-tion of these two products takes place in Patagonia, the country’s largest state, in the Neuquén and the As-tral basins at the base of the Andes Neuquén ac-counts for the bulk of the national production Other long-standing producing basins are the Cuyo, San Jorge, and Magallenes From 1980 to 2010, national gas production more than quadrupled

Argentina is not a world leader in oil and gas ex-ports, but it plays a relatively significant role supplying these products to its South American neighbors The country was the second largest exporter of natural gas

in South America in 2008 Only Bolivia exported more In that year, Argentina ranked fourth in the ex-portation of petroleum in the South America region, behind Venezuela, Brazil, and Ecuador, in decreasing order Argentina’s natural gas and petroleum exports are relatively important to the region, but Venezuela and Bolivia exceed Argentina by far in terms of totals for both resources in production and proved reserves

In 2008, the leading producing company in the coun-try was YPF S.A., followed by Pan American Energy LLC, Petrobrás Energía S.A., and Chevron Argentina S.R.L., in decreasing order

Copper, Gold, and Silver Economists and geologists classify gold and silver as precious metals because of their relatively high value per unit of weight In contrast, owing to the bulk of im-purities of copper ore, copper is considered an

indus-A soybean farmer in the Pampas region of indus-Argentina inspects his harvest (indus-Andres Stapff/Reuters/Landov)

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trial mineral or nonprecious metal Argentina’s

pro-duction of copper, gold, and silver has increased

rapidly Ores of all three metals can form in similar

geological environments For example, all three are

hidden beneath the dry hills of the Puna region in the

country’s northwest corner The Puna also produces

small amounts of tin, lead, zinc, and ferrous minerals

The grassy knolls of Argentina’s north-central region

have gold and porphyry copper, but also small

amounts of nickel-platinum and manganese

One-third of the mining is done in Patagonia, which makes

up the southern third of the country Scattered in the

region are large epithermal gold and silver deposits as

well as polymetallic lead-zinc deposits The last setting

is the magnificent Andes Mountains region, which

has deposits of porphyry copper and gold as well as

chromium The Andes region is where most of

Argen-tina’s mining takes place, although explorations by

mining companies have indicated that great potential

exists for expanded mining in the other three

re-gions Mineral exploration has increased because of

direct foreign investment ventures by Canadian,

Chi-nese, U.S., and British companies, in decreasing

or-der of investment

Together, copper and gold accounted for about 75

percent of the annual value of all mining in the

coun-try in 2006, but copper is by far the more important of

the two minerals Copper accounted for 98 percent of

value of all nonprecious metal ores that were mined

and exported from the country that year However,

gold exports rose rapidly after the opening of the

Veladero Mine in 2006 Catamarca is the leading

pro-ducing province for gold, most of which comes from

the Bajo de la Alumbrera Mine San Juan Province,

where the Veladero Mine is located, is the number-two

producer Other producing provinces are Santa Cruz

and La Rioja Most of the gold produced in Santa

Cruz is from the Cerro Vanguardia Mine A small

amount of gold is from the Martha Mine in La Rioja

Argentina is the fourth-largest producer of silver in

Latin America In 2006, the leading recipients of

Ar-gentina’s metallic ores were Germany, Spain, South

Korea, India, and Brazil

Aluminum and Water Power

The manufacture of aluminum requires the raw

ma-terial alumina and massive amounts of electricity

Argentina’s alumina comes from smelting bauxite

(alumina ore), which the country imports

Hydro-electricity is a necessary power source because it can

be produced more cheaply than electricity generated

by burning expensive fossil fuels The refining of alu-mina is the last step in aluminum production, which begins with exploratory drilling to locate the ore, then removing overburden through blasting and the use of giant earthmoving equipment

Aluar Aluminio Argentino S.A.I.C., or Aluar, is Ar-gentina’s only producer of aluminum The company is

a privately owned stock-trading company that controls every aspect of the aluminum business It converts alumina to primary aluminum and aluminum prod-ucts for use in transportation, construction, electrical, medical, water treatment, and packaging industries Aluar generates its own electricity at its dam on the Futaleufú River in the Andes Mountains The com-pany transfers the electricity via its own power lines to its aluminum factory near Puerto Madryn in Chubut Province The company’s energy consumption has ex-ceeded its capacity for generating hydroelectricity, so

it has supplemented its needs with electricity from burning natural gas, an abundant and a relatively low-cost power source in Argentina More than 80 percent

of Aluar’s production is exported to other countries The products include aluminum bars, tubes, and pro-files (flat-angle shapes) in a variety of sizes and forms Other products include sheet metal and rolls in a wide range of alloys for multiple uses, including foil for dis-posable food containers and for packaging tobacco, pills, food, and other consumer items The primary importers are the United States, Japan, Chile, Brazil, and Mexico

Boron Argentina was the world’s third largest exporter of bo-ron in 2006 Turkey and the United States were first and second, respectively In that year, the country pro-duced 15 percent of the total world supply Boron is processed from borate ore, which formed in ancient lake beds at different times The Puna region, which includes the northwestern corner of Argentina and adjoining areas in Bolivia and Chile, is the main area

of borate deposits in South America The oldest de-posits in Argentina formed from 6 to 1.5 million years ago The Puna is in the high desert of Salta Province, about 4,000 meters above sea level The main pro-ducer of boron in this area is Salta Mining and Energy Resources, an Argentine company Borax, an Ameri-can company, mines boron in the Loma Blanca area southeast of the Puna region Most of Argentina’s pro-duction is exported to South American customers

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Boron-based compounds are used in the

manufac-ture of such items as boric acid, cosmetics, soaps and

detergents, flame retardants, glazes on ceramics,

fi-berglass, and glass fibers

Lithium

In 2006, Argentina produced 12 percent of the total

world production of lithium Lithium is a rare earth

mineral that forms during mountain building, when

igneous activities enrich lithium-bearing ores in silicic

and pegmatite rocks The weathered products of these

rocks are the most economical sources of lithium;

they appear as lithium carbonate and lithium

chlo-ride in rare brine deposits of ancient lake beds

Lith-ium-bearing deposits are in northwestern Argentina,

in the Puna, Loma Blanca, and Salar de Hombre

Muerto areas The lithium division of the FMC

Corpo-ration, an international and publicly traded company,

established the first and largest commercially viable

lithium-mining operation at Salar de Hombre Muerto

That mine produces lithium chloride from the brine

of the salar (salt flat) using a patented ionic exchange

process

Refined lithium is used in the manufacture of

ce-ramics, glass, batteries, lubricating greases,

pharma-ceuticals and polymers, air-conditioning, and primary

aluminum production Lithium use in batteries has

expanded significantly because such batteries have a

much longer lifetime than ordinary batteries do As a

result, lithium batteries have been used increasingly

in portable electronic devices, such as laptop

comput-ers, and in home fire alarms and electrical tools The

greatest potential market is in batteries for plug-in

hy-brid vehicles The potential market in the United

States expanded significantly when General Motors

announced it would introduce a line of hybrid

vehi-cles in late 2009 Argentina’s northwest could see

greater mining of lithium, as the mineral has

increas-ingly become a strategic material for its projected role

in helping alleviate the automobile’s reliance on fossil

fuels

Other Resources

Argentina is one of six Latin American exporters of

lead and zinc, ranking second to Mexico in lead

Other metallic ores that are mined commercially

in-clude nickel, manganese, chromium, titanium, and

molybdenum The country’s marine resources also

enter the global economy, as Argentine fishing

com-panies catch crustaceans and shellfish that they

ex-port primarily to Spain, Italy, Brazil, and France, in de-scending order A fair amount of agricultural land, which is a natural resource that depends on local cli-mate and soil fertility, is planted with feed crops that support the production of dairy products and eggs to Algeria, Venezuela, Brazil, and Chile Additional Ar-gentine exports are timber products (logs, lumber, and pulpwood), mainly to Brazil, South Africa, and France

Richard A Crooker

Further Reading

Arnold, Guy The Resources of the Third World New York:

Cassell, 1997

Crooker, Richard A Argentina Edgemont, Pa.:

Chel-sea House, 2004

Foster, David William, Melissa Fitch Lockhart, and

Darrell B Lockhart Culture and Customs of Argen-tina Westport, Conn.: Greenwood Press, 1998 Garrett, Donald E Borates: Handbook of Deposits, Pro-cessing, Properties, and Use San Diego: Academic

Press, 1998

Kogel, Jessica Elzea, et al., eds Industrial Minerals and Rocks: Commodities, Markets, and Uses 7th ed

Little-ton, Colo.: Society for Mining, Metallurgy, and Ex-ploration, 2006

Lewis, Daniel K The History of Argentina Westport,

Conn.: Greenwood Press, 2001

Rotolo, G C., et al “Energy Evaluation of Grazing

Cat-tle in Argentina’s Pampas.” Agriculture, Ecosystems, and Environment 119, no 3 (March, 2007): 383-395.

Web Sites Central Intelligence Agency The World Fact Book

https://www.cia.gov/library/publications/the-world-factbook/index.html

Food and Agriculture Organization of the United Nations

Country Profiles http://faostat.fao.org/site/342/default.aspx International Trade Centre

Countries http://www.intracen.org/menus/countries.htm U.S Geological Survey

Aluminum http://minerals.usgs.gov/minerals/pubs/

commodity/aluminum/myb1-2006-alumi.pdf

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U.S Geological Survey

Boron

http://minerals.usgs.gov/minerals/pubs/

commodity/boron/boronmcs07.pdf

Lithium

http://minerals.usgs.gov/minerals/pubs/

commodity/lithium/lithimcs07.pdf

2006 Minerals Yearbook, Argentina

http://minerals.usgs.gov/minerals/pubs/country/

2006/myb3-2006-ar.pdf

World Bank

http://www.worldbank.org/

See also: Agricultural products; Agriculture

indus-try; Aluminum; Boron; Farmland; Forests; Lithium;

Oil and natural gas distribution

Army Corps of Engineers, U.S.

Category: Organizations, agencies, and programs

Date: Established 1802

The U.S Army Corps of Engineers has historically

been one of the most important government agencies

affecting the development, use, and conservation of

natural resources, especially water resources Since its

founding in 1802, the organization has engaged in a

multitude of civil and military activities It has

some-times been in conflict with other agencies with

overlap-ping responsibilities.

Background

The U.S Army Corps of Engineers was established by

an act of Congress on March 16, 1802 This legislation

stationed the group at West Point, New York, where, in

addition to performing work on coastal defenses, it

was to operate a military academy that would train

critically needed engineers

Impact on Resource Use

The U.S Army Corps of Engineers’ relationship to

natural resources, particularly water resources, came

into focus gradually One important statement of

na-tional responsibility concerning water came in 1824

when the Supreme Court ruled that the federal

gov-ernment had broad interstate commerce regulatory power, covering river navigation Following this Court decision, Congress gave the Corps of Engineers im-portant responsibilities relating to the development

of civil works During this period, and for a long time thereafter, natural resources were seen as virtually in-exhaustible, and the emphasis was overwhelmingly

on development, not on conservation

The General Survey Act of 1824 seemed to repre-sent a commitment to engage in professional and sys-tematic national planning for resource development However, this was not to be the case Congress, operat-ing accordoperat-ing to procedures that encouraged indi-vidual congressional members to promote localized projects of benefit to their particular constituencies, essentially converted the Corps of Engineers into a tool for spending sizable amounts of federal money in congressional members’ own states and districts The funds were spent on river and harbor improvements and on roads Sometimes the engineers lobbied Con-gress for permission to participate in projects in which they were especially interested Corps activities re-lated to canal-building were most visible Construc-tion of large and increasingly controversial waterways continued until the late twentieth century

By the late twentieth century, support for costly public works projects was far less than it had once been For fiscal as well as environmental reasons, ap-proval for such projects became more difficult than had been the case previously An important piece of legislation bearing on the missions of the U.S Army Corps of Engineers was the Water Resources Develop-ment Act of 1986 It states explicitly that environmen-tal factors are crucial in all planning related to water resources All projects are subject to modification to produce environmental benefits The Corps became committed to an enlightened handling of environ-mental concerns and to safeguarding as well as devel-oping natural resources When the problem of water pollution first began to be perceived as an important area of government concern, the Army Corps of Engi-neers’ position typically was that the problem should

be handled at state and local levels Later, however, the Corps considered its antipollution activities to be among its most important responsibilities

The Corps started promoting flood control in the years following the Civil War Not until 1936 did Con-gress officially state that flood control was a legitimate federal function The Corps played an important role

in the building of levees affecting the

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hurricane-ravaged coastal regions of the states adjacent to the

Gulf of Mexico The Corps has also developed ways

for many areas throughout the country to obtain

water, and many communities draw their water from

Corps projects

William H Stewart

Web Site

U.S Army Corps of Engineers

http://www.usace.army.mil/Pages/default.aspx

See also: Bureau of Land Management, U.S.; Bureau

of Reclamation, U.S.; Dams; Environmental

move-ment; Floods and flood control

Arsenic

Category: Mineral and other nonliving resources

Where Found

Elemental arsenic is occasionally found in minerals,

but more frequently it is combined chemically with

sulfur, either alone or with metals such as copper,

nickel, cobalt, or iron China is the world’s largest

pro-ducer of elemental arsenic Because of the health

risks of arsenic, there has been no U.S production of

arsenic trioxide or arsenic metal since 1985

Primary Uses

Wood preservatives, herbicides, and insecticides are

major uses of arsenic chemicals Arsenic is used to

harden lead alloys for battery plates, solder, and lead

shot, while arsenides of gallium and indium have uses

in lasers, light-emitting diodes, and transistors In the

United States, approximately 4 percent of arsenic

(measured in metric tons of arsenic content) goes to

agricultural chemicals, 3 percent to glass products, 3

percent to nonferrous alloys and electronics, and 90

percent to pressure-treated wood The electronics

industry uses a very pure form of arsenic in

gallium-arsenide semiconductors for solar cells, space

re-search, and telecommunications

Technical Definition

Arsenic (abbreviated As), atomic number 33, belongs

to Group V of the periodic table of the elements and is

classified as a metalloid, rather than a metal or

non-metal There is only one naturally occurring isotope,

with an atomic weight of 74.93 Elemental arsenic ex-hibits gray, yellow, and black forms with densities of 5.73, 1.97, and 4.73 grams per cubic centimeter The common gray form sublimes when heated to 613° Cel-sius and melts under a pressure of 28 atmospheres (2.8 million pascals) at 817° Celsius

Description, Distribution, and Forms Arsenic is widely distributed and is found in soils and seawater in trace amounts: 1 to 40 parts per million in soil, and 2 to 5 parts per billion in seawater It averages about 1.8 parts per million by weight The most abun-dant arsenic mineral is arsenical pyrite (also called ar-senopyrite or mispickel), a sulfide of iron and arsenic Other significant ores are arsenolite (arsenious ox-ide), orpiment (As2S3), and realgar (As4S4) Seawater averages 0.5 to 2 parts per billion of arsenate, but lakes and streams often have higher concentrations; these vary from one body of water to another Lake Michigan, for example, has levels of 0.5 to 2.4 parts per billion Fish and shellfish have arsenic levels about one thousand times greater than seawater and much higher than federal drinking water standards (0.05 part per million) Arsenobetaine, with a formula of (+)(CH3)3As-CH2-CO2(−), is common in fish, and many other methylated compounds are found in ma-rine organisms

Arsenic toxicity is highly dependent on the state of chemical combination of the element Elemental ar-senic is less toxic than combined forms; the most dan-gerous forms are arsine, arsenites, and arsenious ox-ide Ingestion of as little as 0.1 gram of arsenious oxide has caused death Methylated compounds such

as arsenobetaine are much less toxic

Arsenic intoxication symptoms include skin rashes, anemia, gastrointestinal distress, internal bleeding, and shock Chronic poisoning can result in a gangre-nous condition of the feet (“blackfoot disease”), and the action of arsenic as a carcinogen and teratogen has been established Paradoxically, arsenic, like sele-nium, is an essential trace nutrient for some species The toxicity of arsenic is only partly understood, par-ticularly its carcenogenicity Arsenate, AsO4(3−), be-cause of its similarity to phosphate, can react with adenosine, leading to uncoupling of oxidative phos-phorylation, an important energy-producing system

in plants and animals Arsenite, AsO3(3−), inhibits many enzymes by binding to thiol (−SH) groups that exist, for example, in pyruvate oxidase The vital tricarboxylic acid cycle is thereby disrupted

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Admin-istration of antidotes such as penicillamine or

dimer-captopropanol that contain −SH groups will bind

preferentially to the arsenite and keep it from the

en-zymes Ingested arsenic tends to accumulate in the

hair and can be detected by neutron activation

analy-sis Atomic absorption spectroscopy can also detect

and measure trace amounts of arsenic

History

Arsenic was known in early times in India, Persia, and

Mesopotamia, and it is mentioned in the writings of

Aristotle, Hippocrates, and Pliny the Elder These

an-cient writings are often vague and do not allow the

modern reader to decide exactly whether elemental

arsenic or some compound such as an oxide or sulfide

is described European alchemists such as Albertus

Magnus (thirteenth century) and Johannes Schröder

(seventeenth century) published procedures for

pre-paring arsenic from orpiment (As2S3) or arsenious

ox-ide (As2O3), but priority in discovery is considered

un-certain

The toxic characteristics of arsenious oxide were noticed long ago, and the substance became notori-ous in varinotori-ous homicidal poisoning cases The Roman emperor Nero, for example, poisoned his own brother Accidental arsenic poisoning is exemplified by the events reported in 1973 in Pelham, Minnesota, where

a well had been drilled on land that had received heavy dosages of arsenic insecticides

In spite of the danger, pigments containing arsenic were still used in cakes and candy in the nineteenth century, and arsenic-containing medicines of dubi-ous value were used in the early twentieth century Ar-senicals are still occasionally used to treat stubborn parasitic diseases (trypanosomiasis, amoebiasis)

Obtaining Arsenic There are more than two hundred recognized ar-senic-containing minerals Arsenic is leached into water by weathering of rocks and is distributed by vol-canic action In the soil, microorganisms can metabo-lize arsenate or arsenite, producing a variety of

or-Data from the U.S Geological Survey, U.S Government Printing Office, 2009.

Source: Mineral Commodity Summaries, 2009

1,000

11,500

25,000 1,500

1,500

7,000 4,000

1,500 500

Metric Tons

30,000 25,000

20,000 15,000

10,000 5,000

Russia

Mexico

Kazakhstan

China

Chile

Belgium

Morocco

Peru

Other countries

Arsenic Trioxide: World Production, 2008

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ganic methylated compounds that find their way into

water and into the bodies of all sorts of marine

crea-tures An estimated 40,000 metric tons of arsenic are

added to the world’s oceans annually by weathering of

rocks, as compared with world industrial production

of 55,000 to 70,000 metric tons per year

Human activity accounts for significant releases of

arsenic into the air, water, and soil Smelters emit

ar-senic oxide dust, and herbicides and insecticides

re-main in the soil One of the large smelters in the

United States (no longer operating) emitted 181

met-ric tons of arsenious oxide per year into the area

sur-rounding Tacoma, Washington

Uses of Arsenic

Production of arsenic has ceased in the United States,

and uses are subject to increasingly severe regulation

Nevertheless, the United States still imports about

sev-eral thousand metric tons per year, mainly for wood

preservation and pesticide uses

John R Phillips

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