Encyclopedia of Global Resources part 100 doc

Peru Categories: Countries; government and resources Peru is extraordinarily rich in mineral resources, some of which, silver and gold especially, were produced in large quantities in th

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perlite’s distinctive fracture pattern are often called

“perlite” if they contain enough water to expand in a

similar fashion

Description, Distribution, and Forms

Perlite is a form of natural glass Natural glasses form

when molten lava from volcanoes is cooled rapidly

The lava hardens too quickly to allow crystals to grow,

resulting in a substance with a glassy rather than a

stony texture Perlite is distinguished from other

forms of natural glass in that it contains many tiny

curved fractures structured like the layers of an

on-ion These fractures may be microscopic or may be

vis-ible to the naked eye Because of these fractures,

perlite breaks apart into small, round, pearl-like

parti-cles Perlite has a waxy or pearly luster and may be

gray, green, brown, blue, or red The term “perlite” is

also more loosely used to mean any natural glass that

expands into a light, frothy material when heated

Most of the world’s perlite is found in the western

half of the United States New Mexico supplies about

three-quarters of the nation’s perlite Because

under-ground deposits of natural glass slowly crystallize into

stony substances over time, perlite is almost always

found at or near the Earth’s surface Greece,

Hun-gary, Japan, Mexico, and Turkey are also major

pro-ducers of perlite

History

Though perlite has been known as a volcanic rock for

more than two thousand years, it was not used

indus-trially until the twentieth century By the 1970’s, it was

a common product used in the horticultural industry

Obtaining Perlite

Because perlite is found near the surface, it is mined

using the open-pit method It is then crushed to the

desired particle size and transported to a processing

center, where it is heated to expand it

Uses of Perlite

The expanded perlite is used as an aggregate; that is,

it is mixed with other substances such as gypsum to

form plaster or cement to form concrete Although

perlite is not as strong or inexpensive as other

aggre-gates such as sand or gravel, it has the advantages of

being light, fire-resistant, and a good insulator of heat

and sound Perlite is also used as insulation or filler

and in ceramics and filters

Rose Secrest

Web Site U.S Geological Survey Mineral Information: Perlite Statistics and Information

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

commodity/perlite/

See also: Cement and concrete; Glass; Gypsum; Igne-ous processes, rocks, and mineral deposits; Magma crystallization; Open-pit mining; Pumice; Volcanoes

Peru

Categories: Countries; government and resources

Peru is extraordinarily rich in mineral resources, some

of which, silver and gold especially, were produced in large quantities in the Spanish colonial period, as early as the mid-sixteenth century After gaining inde-pendence, Peru took on global importance as a source for a number of other key minerals, especially copper, tin, and, by the late twentieth century, petroleum and natural gas However, Peru suffers from the fact that a large proportion of the exploitation of its natural re-sources is undertaken by foreign companies.

The Country Peru rises from its long western coast along the Pacific Ocean eastward toward the peaks of the Andes Moun-tains It has borders with Bolivia and Chile to the south, with Ecuador, Colombia, to the north, and with Brazil to the east Although much of the country con-sists of high mountains, low coastal regions are hot and dry, running southward to join similar terrain in coastal Chile By contrast, the vast northeastern inte-rior of Peru joins the Amazon River basin, which is characterized by hot, humid tropical forests Peru’s largest city and governmental capital, Lima, is located

on the Pacific coast

Tin Peru is the third largest producer of tin in the world, topped only by China and Indonesia In contrast to most of Peru’s capital-intensive mining ventures, the tin sector is dominated by a family-owned company, Minsur, founded in 1966 The Brescia family kept con-trolling interests following incorporation in 1977 Minsur’s operations are concentrated in the

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south-Peru: Resources at a Glance

Official name: Republic of Peru Government: Constitutional republic Capital city: Lima

Area: 496,261 mi2; 1,285,216 km2

Population (2009 est.): 29,546,963 Languages: Spanish and Quechua Monetary unit: nuevo sol (PEN)

Economic summary:

GDP composition by sector (2008 est.): agriculture, 8.5%; industry, 21.2%; services, 70.3%

Natural resources: copper, tin, silver, gold, petroleum, timber, fish, iron ore, coal, phosphate, potash, hydropower,

natural gas

Land use (2005): arable land, 2.88%; permanent crops, 0.47%; other, 96.65%

Industries: mining and refining of minerals; steel, metal fabrication; petroleum extraction and refining, natural gas;

fishing and fish processing, textiles, clothing, food processing

Agricultural products: asparagus, coffee, cocoa, cotton, sugarcane, rice, potatoes, corn, plantains, grapes, oranges,

pineapples, guavas, bananas, apples, lemons, pears, coca, tomatoes, mango, barley, medicinal plants, palm oil, marigold, onion, wheat, dry beans, poultry, beef, dairy products, fish, guinea pigs

Exports (2008 est.): $31.53 billion

Commodities exported: copper, gold, zinc, crude petroleum and petroleum products, coffee, potatoes, asparagus,

textiles, fishmeal

Imports (2008 est.): $28.44 billion

Commodities imported: petroleum and petroleum products, plastics, machinery, vehicles, iron and steel, wheat, paper Labor force (2008 est.): 10.2 million

Labor force by occupation (2005): agriculture, 0.7%; industry, 23.8%; services, 75.5%

Energy resources:

Electricity production (2008 est.): 30.57 billion kWh

Electricity consumption (2008 est.): 28.97 billion kWh

Electricity exports (2008 est.): 0 kWh

Electricity imports (2008 est.): 0 kWh

Natural gas production (2008 est.): 3.4 billion m3

Natural gas consumption (2008 est.): 3.4 billion m3

Natural gas exports (2008 est.): 0 m3

Natural gas imports (2008 est.): 0 m3

Natural gas proved reserves ( Jan 2008 est.): 334.7 billion m3

Oil production (2008 est.): 110,800 bbl/day Oil imports (2007 est.): 109,000 bbl/day Oil proved reserves ( Jan 2008 est.): 930 million 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.

Lima

Peru

Bolivia Brazil

Chile

Colombia

Ecuador

P a c i f i c

O c e a n

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eastern high-mountain region near Juliaca, more

than seven hundred kilometers from Lima Minsur

also controls the Funsur tin smelting and refining

in-stallation in Pisco, south of Lima Annual production

from its San Raphael mine was more than 38,000

met-ric tons in 2005 Tin mining in Peru, like other sectors

of the mining industry, suffers from recurring strikes

of its workers In midsummer 2008, for example, both

the San Raphael mine and Funsur smelting

opera-tions were shut down as miners tried to pressure the

Peruvian government to pass legislation improving

working conditions and wages not only in tin mining

but also in the copper, gold, silver, and iron ore

sec-tors

Silver

Silver mining has been extremely important for

Peru’s economy since the 1500’s The Spanish

colo-nial administration based in Lima began to exploit a

number of rich veins from the mid-sixteenth century

forward Particularly rich were mines in the region

around the legendary “silver capital” in Potosí (now

in Bolivia), from which Spain shipped an imperial

for-tune in silver ingots both to Europe and to China

In modern times the Caylloma mining district

(about 200 kilometers northwest of Arequipa), among

others areas, continued to mine enough silver to

make Peru the second largest producer in the world,

with potential annual output averaging around 2.8

million kilograms The Vancouver, British Columbia,

mining firm Fortuna Silver obtained 100 percent

fi-nancial control over the main Caylloma operation in

2005, investing major funds to modernize both

min-ing methods and processes used to extract silver from

ore Fortuna transports silver to the port city of Callao

for export marketing Although the Peruvian-run

Buenaventura mining company does not limit itself to

silver mining, its extensive operations place it among

the ten major producers of silver in the world In the

first decade of the twenty-first century, mining

compa-nies like the Canadian Silver Standard and

Colorado-based Apex Silver financed new prospecting projects

along the Pan-American highway transportation

net-work, with particular interest in prospects in Peru

Such projects can run substantial risks (Apex, for

ex-ample, filed preliminary bankruptcy claims in 2009)

Pan American Silver of British Columbia, another

rel-ative “newcomer” founded in 1994, has obtained at

least two Peruvian silver mines that rank among the

top fifteen producers of silver in the world Peru’s

sil-ver output continues to rise, marking gains of almost

10 percent per year (up 9.78 percent between 2008 and the first quarter of 2009) However, apparent ad-vances can be offset by a number of limiting factors One of these is the volatility of global silver prices

An example of Peru’s tactical response to down-ward trends in world silver prices occurred in 1989, when the government attempted to restrict supplies

of silver globally by buying silver from local mining companies (with a premium of 5 percent more than prevailing prices) and stockpiling what it purchased

in hopes that prices would recover within a few months Not only did such tactics fail to attain their goals, but also Peru was criticized internationally for introducing fears of shortages (and price increases)

by disregarding normal world market supply-and-demand principles

Another factor affecting silver output in Peru is la-bor unrest Striking workers at Buenaventura’s Uchuc-chacua mine (deemed to be the largest silver mine in Peru), in Oyón Province near Lima, have caused peri-odic closures, forcing the company to rely on continu-ing but precarious labor cooperation in two other Buenaventura mines (Orcopampa and Antapite) to maintain acceptable levels of production

Gold Estimates indicate that nearly one-half the value (not output) of all mining exports from Peru is earned from gold In 2003, Peru’s mines produced more than 170,000 kilograms of gold, marking clear increases over previous years Although Peru enjoys major earn-ings from gold exports (more than $2 billion in 2003) closer examination of the sector shows that it relies on

a very heavy concentration of foreign companies to exploit this vital resource An example of this is the huge Yanacocha gold mine near Cajamarca in north-ern Peru, considered by many to be the largest and richest gold mine in the world It has produced more than $7 billion of gold, mined out of an open pit measuring more than 250 square kilometers The Peruvian-run mining corporation Compania de Minas Buenaventura (CMB) holds only 43 percent of the mine’s capital, while Newmont Mining, of Denver, Colorado, holds more than 50 percent, with remain-ing capital supplies by the International Finance Cor-poration (under World Bank aegis)

This giant mine, together with the Pierina mine in central northern Peru (developed by the giant Cana-dian Barrick Gold Corporation), has been strongly

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criticized by environmental and human-rights groups,

which charge that irresponsible operations, especially

dangers created by cyanide leach tailing dams, have

gone uncorrected and should be subject to closer

control by the Peruvian authorities

Copper

Peru ranks as the world’s third largest producer of

copper (preceded by Chile and the United States) In

2008, production figures totaled more than 1.2

mil-lion metric tons, most of which was exported

Copper mines are located in several regions of the

country, some (the Toquepala and Cuajone mines)

high in the Andes, 400 kilometers southeast of Lima;

others (mainly the La Granja copper mine) also in the

Andes, northeast of the capital The Toquepala and

Cuajone mines, originally discovered by a German

freelance miner/explorer, have been exploited for

more than a century Since the mid-1950’s a giant

firm, the Southern Peru Copper Corporation (SPCC,

with major stakes at that time held by four U.S

compa-nies), has been the prime motor for exploitation of Toquepala and Cuajone SPCC has undergone a num-ber of major changes, especially between 1968 (when

a Peruvian military junta cancelled large parts of its concession) and the conclusion of agreements in the mid-1970’s, leading to expansion of production in the Cuajone mining zone In the 1990’s, SPCC profits set records when global copper prices were at an all-time high In 1999, another major change came when Grupo Mexico bought out the Tucson, Arizona, com-pany ASARCO’s shares in SPCC (at a cost of $2.5 bil-lion), thereby gaining a 54 percent majority interest

in the giant firm

Although the SPCC’s activities are unique, one can gain an impression of the overall status of Peruvian copper on the international market from SPCC’s an-nual production and export sales figures When cop-per prices slumped in 1999 (eventually reaching the lowest point in sixty years, at about twenty-seven cents per kilogram), SPCC was producing more than 337 million kilograms yearly (yielding about 250 million

Peruvians depend on water provided by glaciers like this one in the Andes Mountains of Patawasi (Getty Images)

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kilograms of refined copper) Leading up to what

be-came a turning point at the end of the 1990’s, sales of

SPCC’s Peruvian copper were going to Northern

Eu-rope (about 34 percent), Asia (30 percent), other

Latin American countries (about 15 percent), and

the United States (4 percent) Even though a partial

recovery of global prices brought copper back to

nearly two dollars per kilogram by 2006, chances of

continued fluctuation continued to suggest that the

halcyon days of copper returns were unlikely in the

first decade of the twenty-first century

However, some developments after 2000 suggested

that Peru’s global position could change, as plans for

exploiting new or previously only partially exploited

reserves went forward Notable new developments

were symbolized by the emergence after October,

2001, of the Antamina company’s exploitation of

what may be one of the largest reserves of copper and

zinc in the world Antamina operations are located

almost 300 kilometers north of Lima and have a

state-of-the-art pipeline connection capable of carrying

slurry, or processed and concentrated ore mixed with

water, to coastal transshipment facilities Joint

partici-pating members of the Antamina operation include

one-third capital subscription by Noranda,

Incorpo-rated (one of the world’s largest mining companies,

originally founded in Ontario, Canada); one-third

held by BHP Billiton Base Metals (a multinational

gi-ant originally involved in tin mining in the nineteenth

century in the Dutch East Indies—later Indonesia—

taken over by Royal Dutch Shell in the 1970’s); and

the remainder split between Teck Cominco (of

Van-couver, British Columbia) and the Mitsubishi

Corpo-ration of Japan This situation of Peruvian

depen-dence on foreign investment for exploiting mineral

resources is as visible, and potentially even more

con-troversial, in another key sector: petroleum and

natu-ral gas

Petroleum and Natural Gas

Beginning in the 1970’s, the Upper Amazonian area

of Peru promised to offer an important addition to

the country’s exportable resources From relatively

modest 1977 figures (export values of $52 million),

production increased rapidly to almost $650 million

in 1985

By 2000, estimates of known oil reserves topped

350 million barrels By 2001, production was more

than one hundred thousand barrels a day In

addi-tion, Peru possesses, at Camisea, deep within the

Am-azonian rain forest, what is deemed to be the largest natural gas field in South America Although the exis-tence of natural gas reserves was known for some time, operational exploitation of the Camisea field dates from only 2004 Gas was initially transported

by impressive pipelines over the Andes to the Pacific Ocean port of Pisco In 2007 and 2008, following rising controversy over pipeline leakage, two foreign firms, Suez Energy and Kuntur Gas Transport, pre-sented the Lima government with proposals to build two more efficient pipelines, one of which would end and be combined with a gas-run power plant at the port zone of Ilo in southern Peru In 2009, Suez En-ergy predicted that its pipeline facilities could be-come operational by 2011

It is impossible to discuss plans to expand exploita-tion of Peru’s petroleum and natural gas resources without mentioning operations in the northern pre-Amazon, with a proposed pipeline system of transport

to Talara on the Pacific coast The Camisea Project, which aims at involving a number of multinational companies in exploitation of northern Amazonian re-serves, projects delivery of gas and oil to the United States, Mexico, and other countries bordering the Pa-cific In 2003, in order to encourage the Camisea Proj-ect, the Peruvian government reduced royalties that would normally be owed to it by foreign concession-aires As plans moved ahead, an unprecedented pub-lic reaction—mainly from ecologists abroad—criti-cized the project as not only ecologically destructive but also a menace looming over the lives of indige-nous tribal populations in the tropical forest area to

be affected Critics underline Camisea’s apparent dis-regard for respecting the ecological conditions that traditionally support very rare flora; among them ex-ist approximately seventy plants that are considered important in pharmaceutical treatment of cancer

Other Resources Peru is not a major producer of iron, although the one important company involved in iron-ore mining (Shougang Hierro Peru, a Chinese-owned business with head offices in Lima) has succeeded in increas-ing the country’s production of ore in stages From a production level of about 3 million metric tons of ore exported in 2003, valued at about $95 million, the company registered a notable annual increase, reach-ing 4 million metric tons in 2005 Shougang Hierro Peru operates several open-pit mines in the coastal desert region about 500 kilometers south of Lima A

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combination of conveyor belts and a trucking

net-work connects the mines to the Pacific coast port of

San Nicolas, from which the ore is exported

Although there is only one significant manganese

mining area in Peru (at Berenguela in the

southeast-ern zone), already existing exploitation of copper

and silver at that location was substantial enough for

one company, Lampa Mining, to hold exclusive

min-ing rights for more than half a century (between 1905

and 1965) About 500,000 metric tons of ore were

ex-tracted by Lampa, but only a small part of the

manga-nese content of this mass was processed for sale In

later decades manganese extraction became more

economically viable and attracted a Canadian firm,

Blackstone Resources, to acquire 80 percent interest

in a Peruvian holding company venture, the Mining

Society of Bernguela (SOMINBESA)

Byron D Cannon

Further Reading

Arellano-Yanguas, Javier A Thoroughly Modern Resource

Curse? The New Natural Resource Policy Agenda and the

Mining Revival in Peru Brighton, East Sussex,

En-gland: Institute of Development Studies at the

Uni-versity of Sussex, 2008

DeWind, Josh Peasants Become Miners: The Evolution of

Industrial Mining Systems in Peru New York:

Gar-land, 1987

Dore, Elizabeth The Peruvian Mining Industry: Growth,

Stagnation, and Crisis Boulder, Colo.: Westview

Press, 1988

Hall, Anthony L Amazonia at the Crossroads: The

Chal-lenge of Sustainable Development London: Institute of

Latin American Studies, 2000

See also: Copper; Ecozones and biogeographic

realms; Forests; Gold; Silver; Tin

Pesticides and pest control

Categories: Environment, conservation, and

resource management; pollution and waste

disposal

Pesticides are agents used to kill or otherwise control

or-ganisms that are harmful to humans or crops In

addi-tion to chemical agents, alternative pest-control

meth-ods are available.

Background

An animal or plant is regarded as a pest if it causes a nuisance or harm to humans or crops or otherwise negatively impacts human health, well-being, or qual-ity of life Pests such as silverfish consume paper and fabrics Termites cause serious damage to houses and other wooden structures Weeds, aphids, and snails play havoc with flower gardens Beetles and fungi at-tack shade trees, timber, crops, orchards, and stored foods Mosquitos, ticks, mites, and rodents transmit vi-ruses and other disease organisms to humans Pest control is the ongoing process of managing in-sects, rodents, weeds, fungi, and other pest organisms where their lives intersect human lives The twentieth century saw a rapid escalation in the use of chemical pesticides, which have become a mainstay of pest con-trol These chemicals have suppressed pest popula-tions, increased crop yields, protected property, and kept disease in check However, indiscriminate use of chemical pesticides has damaged the environment, which has led to governmental regulation of pesti-cides, outright bans on some substances, and increased interest in alternative pest-control methods

Types of Chemical Pesticides Chemical pesticides are often classed based on the or-ganisms that they target Avicides kill or repel bird pests Rodenticides are for use against rats and mice Acaracides and miticides target ticks and mites Insec-ticides, the largest category of pesticide, are used against insects Nematicides are used to kill nema-todes, soil- and water-dwelling roundworms that are often parasitic on plants and animals Fungicides are used to treat crops and other plants for fungal (and sometimes bacterial) conditions such as root rot, smut, gall, rust, and blight Herbicides target the weeds and other unwanted vegetation that encroach on lawns, gardens, crops, and paths Defoliants are a class of herbicide that induces leaf fall from trees and other plants

Pesticides can also be categorized on the basis of chemical composition Mineral pesticides such as ar-senic, borax, copper, lead, and zinc were among the first pesticides employed by humans; these minerals have mostly been replaced by more efficient chemical compounds Botanical pesticides are insecticidal sub-stances derived from plants or are synthetic analogs to such substances These include pyrethrins, chrysan-themum-derived insecticides which are not highly toxic to humans Chlorinated hydrocarbons, which

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include chlorine, hydrogen, and oxygen in

their chemical makeup, are highly effective

poisons that do not readily degrade in the

envi-ronment Compounds such as aldrin, endrin,

dieldrin, chlordane, and

dichloro-diphenyl-trichloroethane (DDT) were widely employed

before the environmental implications of their

persistence were fully understood

Organo-phosphate pesticides are organic Organo-phosphate

compounds that break down in the

environ-ment more easily than the chlorinated

hydro-carbons, particularly in the presence of water

Examples include malathion, naled,

dichlor-vos, methyl and ethyl parathion, and diazinon

Carbamates, characterized by carbamic acid,

include carbaryl, carbofuran, and

methylcar-bamate; these compounds degrade more

quickly than organophosphates

Pesticides may be categorized further as

se-lective or nonsese-lective A sese-lective pesticide

targets a particular pest, while a nonselective pesticide

(also called a broad-spectrum or general-usage

pesti-cide) is toxic to a wide range of organisms and does

not confine its effects to the target species once it is

re-leased into the environment Selectively toxic

chemi-cals minimize the pesticide’s impact on the

environ-ment Chemical pesticides are applied in various

forms, including wet sprays, dusts, atomizable fluids,

low-pressure aerosols, smokes, gases, and seed

treat-ments

History of Use

The “first generation” of chemical pesticides was the

minerals and botanicals In 1867, farmers in the

United States began using Paris green, a

then-com-mon pigment containing arsenic and copper, to

con-trol outbreaks of the Colorado potato beetle Lead

arsenate was introduced as an insecticide in 1892 By

the 1920’s, pesticide use in the United States had

become commonplace, and concerns over arsenical

residues in foods had begun to arise

In 1939, the next generation of chemical pesticides

was ushered in with the discovery of DDT’s

insecti-cidal properties The compound was first

dissemi-nated on a large scale during the Naples typhus

epi-demic of 1943-1944, and it found widespread use

during the remainder of World War II DDT and

other potent broad-spectrum poisons were popular

pesticides from the early 1940’s through the 1960’s

However, as concerns mounted over the

environmen-tal impact of these chemicals—contaminated water-sheds; the dying off of beneficial species coupled with pests becoming pesticide resistant; the accumulation

of pesticides in the bodies of higher animals, includ-ing humans; and poisoned food chains—use of chlo-rinated hydrocarbons fell into disfavor Use of DDT and similar chemicals has been banned or restricted

in many countries, including the United States The disadvantages of chemical pesticides have led

to an increased interest in alternative pest-control methods Biological control agents include microor-ganisms that are harmful to pests but not to other life; natural predators and parasites; and the release of large numbers of laboratory-sterilized insects, which then mate with normal insects without producing off-spring While biological control agents usually involve

no environmental pollutants and are often highly se-lective, the many complex factors that affect their ac-tion sometimes hinder their effectiveness

U.S Regulation of Chemical Pesticides The Insecticide Act of 1910 prohibited adulteration

of insecticides and fungicides In 1947, the Federal In-secticide, Fungicide, and Rodenticide Act (FIFRA) authorized the United States Department of Agricul-ture (USDA) to oversee registration of pesticides and

to determine their safety and effectiveness In Decem-ber, 1970, the newly formed U.S Environmental Pro-tection Agency (EPA) assumed statutory authority from the USDA over pesticide regulations Under the

An American farmworker takes health precautions while preparing pesticides for use on crops (United States Department of Agriculture)

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Federal Environmental Pesticide Control Act of 1972,

an amendment to FIFRA, manufacturers must

regis-ter all marketed pesticides with the EPA before the

product is released Before registration, the chemicals

must undergo exhaustive trials to assess their

poten-tial impact on the environment and human health

The EPA’s decision to grant registration is based on

the determination that unreasonable adverse effects

on human health or the environment are not

antici-pated within the constraints of approved usage

Be-ginning in October, 1977, the EPA has classified all

pesticides to which it has granted registration as either

a restricted-usage (to be applied only by certified pest

control operators) or unclassified (general-usage)

pes-ticide

Karen N Kähler

Further Reading

Carson, Rachel Silent Spring Drawings by Lois and

Louis Darling Boston: Houghton Mifflin, 1962

Cremlyn, R J Agrochemicals: Preparation and Mode of

Ac-tion New York: Wiley, 1991.

Levine, Marvin J Pesticides: A Toxic Time Bomb in Our

Midst Westport, Conn.: Praeger, 2007.

Lopez, Andrew Natural Pest Control: Alternatives to

Chemicals for the Home and Garden Rev ed Malibu,

Calif.: Invisible Gardener, 2005

Matthews, G A Pesticides: Health, Safety, and the

Envi-ronment Ames, Iowa: Blackwell, 2006.

Stenersen, Jørgen Chemical Pesticides: Mode of Action

and Toxicology Boca Raton, Fla.: CRC Press, 2004.

Ware, George W Fundamentals of Pesticides: A

Self-Instruction Guide 3d ed Fresno, Calif.: Thomson,

1991

Ware, George W., and David M Whitacre The Pesticide

Book 6th ed Willoughby, Ohio: MeisterPro

Infor-mation Resources, 2004

Whorton, James Before “Silent Spring”: Pesticides and

Public Health in Pre-DDT America Princeton, N.J.:

Princeton University Press, 1974

Web Site

U.S Environmental Protection Agency

About Pesticides

http://www.epa.gov/pesticides/about/index.htm

See also: Agriculture industry; Carson, Rachel;

Envi-ronmental Protection Agency; Food chain;

Herbi-cides; Monoculture agriculture

Petrochemical products

Category: Products from resources

Petrochemicals are organic chemicals derived from petro-leum or natural gas They are of extreme importance in contemporary life, accounting for the production of al-most all plastics, other synthetic materials, and organic chemicals Although an enormous variety of organic chemicals can be (and are) made from petroleum or nat-ural gas, usually the term “petrochemicals” is restricted

to those substances produced in very large amounts.

Background The origin of the petrochemical industry may be traced to the first production of isopropyl alcohol from propylene in 1920 This effort was originated by the Standard Oil Company in New Jersey The indus-try grew slowly but steadily during the 1920’s and 1930’s and then received an enormous boost from World War II, with its tremendous demand for syn-thetic materials By about 1950 the industry was firmly established in the United States

Ethylene and Polyethylene The most important petrochemical is ethylene It is manufactured in greater quantity than any other or-ganic chemical Various raw materials can be used to manufacture ethylene, including ethane, propane, and petroleum distillates such as naphtha Regardless

of the raw material, the ethylene production process involves thermally driven reactions (so-called crack-ing) in a temperature range between 750° and 900° Celsius Steam is used to dilute the feed to the ethyl-ene production furnace The amount of steam used varies, depending on the specific material used to make the ethylene The annual worldwide produc-tion of ethylene exceeds 100 million metric tons About half of the ethylene produced is converted

to polyethylene The two major types of polyethylene are known as low-density polyethylene (often abbre-viated as LDPE) and high-density polyethylene (HDPE) One of the most important applications of LDPE is in clear plastic wrapping film HDPE has a wider range of uses by virtue of its superior mechani-cal properties Familiar applications of HDPE include bottles, such as those used for laundry detergents, and housewares, such as storage crates and home cleaning accessories such as buckets, pans, and pails

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Vinyl Chloride and Ethylene Glycol

A second major use of ethylene is its conversion to

vi-nyl chloride This conversion is effected by a process

called oxychlorination: reaction of ethylene with

hy-drogen chloride and oxygen Vinyl chloride is used in

the manufacture of polyvinyl chloride, or poly, most

commonly known as PVC Depending on how the

PVC is produced (specifically, through the addition

of “plasticizers” that alter its physical or mechanical

properties), it can have a range of hardness and

flexi-bility Consequently, PVC is a versatile material with

many common uses that include floor tile, garden

hose, artificial leather, house siding, plastic films,

pipe, and toys In the days when music was recorded

on phonograph records, they were usually made of

PVC—hence the slang term “vinyl.”

The oxidation of ethylene produces ethylene

ox-ide, a chemical that easily reacts with water to form

ethylene glycol, a useful component of antifreeze

Ethylene glycol is also used in the manufacture of

polyethylene terephthalate, commonly known as PET

This polymer is an example of the largest class of

syn-thetic textile fibers, the polyesters PET is also used

for both audio and video magnetic recording tapes,

in soft drink bottles, and in “microwave-in-a-pouch”

food containers

Propylene, Polypropylene, and Propylene

glycol

Propylene is the second most important of the

petro-chemicals Although ethylene superseded it in

impor-tance (in terms of tonnage production), propylene was the first significant petrochemical In the 1920’s and 1930’s, propylene was a by-product of gasoline manufacture To increase the yield of gasoline from a refinery, other petroleum products of lower value were subjected to intense heating (thermal cracking), which broke the molecules into new, smaller com-pounds, many of which could be used in gasoline In addition, however, thermal cracking led to some by-products, such as propylene, of molecular size even smaller than gasoline The beginning of the petro-chemical industry was the use of this by-product pro-pylene for producing isopropyl alcohol Most people encounter isopropyl alcohol primarily as the active in-gredient in “rubbing alcohol,” but it has more impor-tant uses as an industrial solvent and as raw material for making acetone, another useful solvent

Today the propylene situation is greatly changed The thermal cracking process for gasoline is obsolete,

so there is no by-product propylene Instead, propyl-ene is made in much the same way as ethylpropyl-ene, using either propane or naphtha as the raw material The raw material, mixed with steam, is cracked at tempera-tures of 800° to 900° Celsius The dominant use of propylene is in the production of polypropylene The properties of polypropylene—and conse-quently its uses—depend heavily on the way the pro-pylene molecules are connected Special catalysts to control the outcome of the polymerization of poly-propylene were discovered by Karl Ziegler and Giulio Natta, for which achievement they were awarded the

1963 Nobel Prize in Chemistry A common application for high-qual-ity polypropylene is in microwave-safe dishes and food containers Some of the lower-strength grades of polypropylene are useful as flexible, clear plastic films—for example, as food wrap and as the plastic cover-ings on disposable diapers Poly-propylene and “copolymers” of poly-propylene and polyethylene are widely used as materials in automo-biles Examples of automotive appli-cations include bumper covers, air ducts, body trim panels, interior trim and seat covers, and battery casings Propylene can also be converted

to propylene oxide and then to pro-pylene glycol This material is used

This 1942 display of petrochemical products illustrates the United States’ shift away from

cost-prohibitive metals during World War II Plastic products have became integral in

multiple aspects of modern life (AP/Wide World Photos)

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directly in antifreeze, brake fluid, and hydraulic fluid.

It is also used as a moisturizer in pet foods and tobacco

products Propylene glycol is converted to a special

family of compounds called urethanes, the basic

ma-terials for the production for polyurethane products

Many kinds of urethanes can be made from propylene

glycol, depending on the chemicals chosen for the

process Consequently, the eventual polyurethanes

have, as a family, a wide range of properties Common

applications of polyurethanes include sound and heat

insulation, furniture cushions, automobile bumpers,

and plastic flooring and roofing

Acrylics, Polyacrylates, and

Polyacrylonitrile

A more severe oxidation of propylene leads to acrylic

acid, the starting material for acrylic paints Sodium

or ammonium salts of acrylic acid polymerize to the

polyacrylates When polyacrylates are mixed with small

amounts of other copolymers, they form polyacrylate

“super-absorbing” polymers that have an exceptional

capacity for absorbing water or water solutions The

major use of these remarkable materials is in the

lin-ing of disposable diapers

The reaction of propylene with ammonia in the

presence of oxygen (“ammoxidation”) forms

acrylo-nitrile This is the starting material for

polyacryloni-trile, or PAN Acrylic textiles, such as Acrilan and

Or-lon, amount to about 20 percent of all synthetic fibers

produced PAN is also used to make carbon fibers

Ini-tially, PAN-based carbon fibers were extremely

expen-sive (about $100 per kilogram), so they were limited

to military and aerospace applications As an

exam-ple, about 10 percent of the weight of an F-18 fighter

aircraft is PAN-based materials Other applications

in-clude use in the space shuttle’s cargo bay doors and in

nozzles in the shuttle’s rockets Improved

manufac-turing know-how reduced the cost of carbon fibers

sig-nificantly, and carbon- or graphite-fiber items are

in-creasingly available to consumers; among them are

graphite tennis rackets and golf clubs

The BTX Compounds and Styrene

Catalytic reforming of petroleum, a process used to

enhance the octane number of gasoline, produces as

by-products the family of compounds benzene,

tolu-ene, and xyltolu-ene, sometimes lumped together and

called BTX They are high-tonnage materials but not

as important as ethylene and propylene

Benzene and ethylene react to produce

ethylben-zene, which is converted to styrene Styrene is the raw material for making polystyrene Polystyrene is an-other example of the petrochemical products that seem ubiquitous in modern life Applications of poly-styrene include Styrofoam food cartons (such as those used for eggs in supermarkets), cups and food pack-aging at fast food restaurants, plastic utensils, toys, and the foam “peanuts” used as packaging material Polystyrene and other uses of benzene are so impor-tant that the major use of toluene is conversion to benzene Xylenes are used as solvents One particular xylene, para-xylene, is converted to terephthalic acid This compound, reacted with ethylene glycol (de-scribed above), produces PET

The petrochemical industry has an immense eco-nomic impact, both in the United States and world-wide In the United States, twenty-nine of the top fifty industrial chemicals are organic (though not all are petrochemicals)

Harold H Schobert

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