Environmental Encyclopedia

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Environmental Encyclopedia 3

Arctic National Wildlife Refuge

succession

of studies has been conducted on the

chemistry of the particles in that

haze

, and those trapped

in the snow and ice. Much of the time the mix of trace

elements in the particles is very close to that found in the

industrial emissions from northern Europe and Siberia and

quite different from that in such emissions from northern

North America. Concentrations decrease rapidly with depth

in the ice layers, indicating that these trace elements began

to enter the atmosphere within the past few centuries. It is

now generally conceded that most of the haze particles are

derived from human activities, primarily—though not exclu-

sively—in northern Eurasia.

Since the haze scatters light, including sunlight, it

decreases the

solar energy

received at the ground level in

polar regions and may, therefore, have the potential to de-

crease arctic temperatures. Arctic haze also constitutes a

nuisance because it decreases visibility. The trace elements

found in arctic haze apparently are not yet sufficiently con-

centrated in either atmosphere or precipitation to constitute

a significant toxic hazard.

[James P. Lodge Jr.]

ESOURCES

ERIODICALS

Nriagu, J. O., et al. “Origin of Sulfur in Canadian Arctic Haze From

Isotope Measurements.” Nature 349 (10 January 1991): 142–5.

Soroos, M. S. “The Odyssey of Arctic Haze: Toward a Global Atmospheric

Regime.” Environment 36 (December 1992): 6–-11+.

Arctic National Wildlife Refuge

Beyond the jagged Brooks Range in Alaska’s far northeastern

corner lies one of the world’s largest

nature

preserves, the

19.8-million acre (8-million ha) Arctic

National Wildlife

Refuge

(ANWR). A narrow strip of treeless coastal plain

in the heart of the refuge presents one of nature’s grandest

spectacles, as well as one of the longest-running environmen-

tal battles of the past century. For a few months during the

brief arctic summer, the

tundra

teems with

wildlife

. This

is the calving ground of the 130,000 caribou of the Porcupine

herd, which travels up to 400 mi (640 km) each summer to

graze and give birth along the Arctic Ocean shore. It also

is important

habitat

for tens of thousands of snow geese,

tundra swans, shorebirds and other migratory waterfowl; a

denning area for polar bears, arctic foxes and arctic

wolves

;

and a year-round home to about 350 shaggy musk ox. In

wildlife density and diversity, it rivals Africa’s Serengeti.

When Congress established the

Wildlife Refuge

1980, a special exemption was made for about 600,000 ha

(1.5 million acres) of coastline between the mountains and

the Beaufort Sea where geologists think sedimentary strata

may contain billions of barrels of oil and trillions of cubic

feet of

natural gas

. Called the 1002 area for the legislative

provision that put it inside the wildlife refuge but reserved

the right to drill for

fossil fuels

, this narrow strip of tundra

may be the last big, on-shore, liquid

petroleum

field in

North America. It also is

critical habitat

for one of the

richest biological communities in the world. The possibility

of extracting the fossil fuels without driving away the wildlife

and polluting the pristine landscape is supported by oil indus-

try experts and disputed by biologists and environmentalists.

The amount of oil and gas beneath the tundra is uncer-

tain. Only one seismic survey has been done and a few test

wells

drilled. Industry geologists claim that there may be

16 billion barrels of oil under ANWR, but guessing the size

and content of the formation from this limited evidence is

as much an art as a science. Furthermore, the amount of oil

it’s economical to recover depends on market prices and

shipping costs. At current wholesale prices of $25 per barrel,

the U.S.

Geological Survey

estimates that 7 billion barrels

might be pumped profitably. If prices drop below $10 per

barrel, as they did in the early 1990s, the economic resource

might be only a few hundred million barrels.

Energy companies are extremely interested in ANWR

because any oil found there could be pumped out through

the existing

Trans-Alaska pipeline

, thus extending the life

of their multibillion-dollar investment. The state of Alaska

hopes that revenues from ANWR will replenish dwindling

coffers as the oil supply from near-by Prudhoe Bay wells

dry up.

Automobile

companies, tire manufacturers, filling

stations, and others who depend on our continued use of

petroleum argue that domestic oil supplies are rapidly being

depleted, leaving the United States dependent on foreign

countries for more than half of its energy consumption.

Oil drilling

proponents point out that prospecting will

occur only in winter when the ground is covered with snow

and most wildlife is absent or hibernating. Once oil is lo-

cated, they claim, it will take only four or five small drilling

areas, each occupying no more than a few hundred hectares,

to extract it. Heavy equipment would be hauled to the sites

during the winter on ice roads built with water pumped

from nearby lakes and rivers. Each two-meter-thick, gravel

drilling pad would hold up to 50 closely spaced wells, which

would penetrate the

permafrost

and then spread out hori-

zontally to reach pockets of oil up to 6 mi (10 km) away

from the wellhead. A central processing facility would strip

water and gas from the oil, which would then be pumped

through elevated, insulated pipelines to join oil flowing from

Prudhoe Bay.

Opponents of this project argue that the noise,

pollu-

tion

, and construction activity accompanying this massive

operation will drive away wildlife and leave scars on the

landscape that could last for centuries. Pumping the millions

Environmental Encyclopedia 3

Arctic National Wildlife Refuge

A map of the Arctic National Wildlife Refuge (ANWR) in Alaska. (Map by World Management. Reproduced by permission.)

of gallons of water needed to build ice roads could dry up

local ponds on which wildlife depends for summer habitat.

Every day six to eight aircraft—some as big as the C-130

Hercules—would fly into ANWR. The smell of up to 700

workers and the noise of numerous trucks and enormous

power-generating turbines, each as large and loud as a jumbo

aircraft engine, would waft out over the tundra. Pointing to

the problems of other Arctic oil drilling operations where

drilling crews dumped

garbage

, sewage, and toxic drilling

waste into surface pits, environmentalists predict disaster if

drilling is allowed in the refuge. Pipeline and drilling spills

at Prudhoe Bay have contaminated the tundra and seeped

into waterways. And scars from bulldozer tracks made 50

years ago can still be seen clearly today. John Adams, Presi-

dent of the

Natural Resources Defense Council

claims

that the once pristine wildlife habitat of Prudhoe Bay has

become a toxic, industrial wasteland.

Oil companies planning to drill in ANWR, on the

other hand, claim that old, careless ways are no longer per-

mitted in their operations. Wastes are collected and either

burned or injected into deep wells. Although some animals

do seem to have been displaced at Prudhoe Bay, the Central

Arctic herd with 27,000 caribou is five times larger now

than it was in 1978 when drilling operations began there.

But in ANWR the Porcupine herd has five times as many

animals crowded into one-fifth the area and may be much

more sensitive to disturbance than their cousins to the west.

Native people are divided on this topic. The coastal

Inupiat people, many of whom work in the oil fields, support

opening the refuge to oil exploration. They hope to use their

share of the oil revenues to build new schools and better

housing. The Gwich’in people, who live south of the refuge,

would gain nothing from oil exploitation. They worry that

migrating caribou on which they depend might be decline

as a result of drilling on critical calving grounds.

Even if ANWR contains seven billion barrels of oil,

it will take at least a decade to begin to get it to market and

the peak production rate will probably be about one million

barrels of oil per day in 2030. Flow from the 1002 area would

then meet less than 4% of the U.S. daily oil consumption.

Improving the average fuel efficiency of all cars and light

trucks in America by just one mile per gallon would save

more oil than is ever likely to be recovered from ANWR,

Environmental Encyclopedia 3

Arid landscaping

and it would do so far faster and cheaper than extracting

and transporting crude oil from the arctic. Cutting our fossil

fuel consumption also is vital if we are to avoid catastrophic

global

climate

change.

In 1995, Congress passed a budget that included a

provision to allow drilling in ANWR, but President Bill

Clinton vetoed the bill. In 2002, the Republican-controlled

House of Representatives once again passed an energy bill

that authorized oil and gas exploration in ANWR. President

Bush strongly supported this bill and promised to sign it if

given an opportunity. The Senate energy bill, however, re-

jected ANWR drilling by a vote of 54 to 46, and the measure

was abandoned by its sponsors.

Undoubtedly, this debate won’t disappear anytime

soon. With a potential of billions of dollars to be made from

oil and gas formations, the industry won’t give up easily.

For many conservatives, this issue has become a matter of

principle. They believe we have both a right and a duty to

exploit the resources available to us. Environmental groups

feel equally strongly about the value of wildlife,

wilderness

and one of the “last remaining great places” in the world.

Protecting this harsh but beautiful land garnered more dona-

tions and public passions than any other environmental issue

in the past decade. Clearly, how we decide to manage

ANWR will be a landmark in

environmental history

[William P. Cunningham]

ESOURCES

OOKS

Lentfer, Hank and Carolyn Servid, eds. Arctic Refuge: A Circle of Testamony.

Minneapolis, MN: Milkweed Press, 2001.

ERIODICALS

Gibbs, W. Wayt. “The Arctic Oil & Wildlife Refuge.” Scientific American

284(2001): 62-69.

Miller, Debbie S. “Ground Zero” The Amicus Journal 23(2001): 29-34.

McGrath, Susan. “The last great wilderness.” Audubon 103(2001): 52-65.

Rauber, Paul. “Snake Oil for Fossil Fools.” Sierra 88(2001): 56-61,86-87.

Arid

Arid lands are dry areas or deserts where a shortage of rainfall

prevents permanent rain-fed agriculture. They are bordered

by, and interact with, marginal or semi-arid lands where the

annual rainfall (still only 10–15 in; 25–38 cm) allows limited

agriculture and light grazing. However, in many parts of the

world human mismanagement, driven by increasing popula-

tions, has degraded these areas into unusable arid lands. For

example, clearing natural vegetation and

overgrazing

have

led to

soil erosion

, reduced land productivity, and ultimately

reduced water availability in the region. This degradation

of semi-arid lands to deserts, which can also occur naturally,

is known as

desertification

Arid landscaping

Arid

landscaping, or xeriscaping (from the Greek word xeros,

meaning dry), is the integration of practicality and beauty

in drought-prone public and private gardens. Xeriscaping is

part of a larger trend among environmentalist gardeners to

incorporate native rather than imported

species

within local

ecosystems.

In drought-prone areas like California, where

water

conservation

is imperative and lawns and flower gardens

are at risk, gardeners have taken several steps to cope with

drought

. A 20-by-40-ft (6-by-12 m) green lawn requires

about 2,500 gal (9,475 l) of water a month, enough for

a four-member family for 10 days. Some arid landscapers

eliminate lawns altogether and replace them with flagstone

or concrete walkways; others aerate the

soil

or cut the grass

higher for greater water retention. More popular is replacing

imported grasses with native grasses, already adapted to the

local

climate

, and letting them grow without being cut.

Some big trees, such as oak, do better in drought than

others, such as birches or magnolias. To save big trees that are

expensive and important providers of shade, some gardeners

place “soaker” hoses, in which water flows out through holes

in the length of the hose in concentric circles at the base of

trees and water them deeply once or twice a season.

More commonly, arid landscapers replace water-loving

shrubs and trees with those best adapted to drought condi-

tions. These include some herbs, such as rosemary, thyme,

and lavender, and shrubs like the silvery santolina, which

are important in color composition of gardens.

Other plants that grow well in semi-arid and arid

conditions are legumes (Leguminosae), poppies (Papavera-

ceae), daisies (Compositae), black-eyed susans (Rudbeckia

fulgida), goldenrod (Solidago), honeysuckle (Lonicera), sun-

flowers (Helianthus), daylilies (Hemerocallis), and eucalyptus.

Generally, drought-resistant plants have silvery leaves that

reflect sunlight (argentea); hairy (tomentosum) or stiff haired

(hirsuta) leaves that help retain moisture; long narrow leaves

(angustifolia), threadlike leaves (filimentosa), and aromatic

leaves (aromatica) that provide a moisture-protecting

haze

in heat.

Drip irrigation

, hoses with small regular holes, whose

amount is regulated by timers, is the most efficient xeriscape

watering technique. Mulching with dead leaves, pine bark,

straw, and other organic matter helps retain soil moisture.

Soil types are a critical part of arid landscaping: one inch

(2.5 cm) of water, for example, will penetrate 6–8 in (15–

Environmental Encyclopedia 3

Army Corps of Engineers

20 cm) into loam (a sand, peat, and clay mixture), but only

4–5 in (10–13 cm) into dense clay.

Arid landscapers monitor plant health and soil dryness

only when necessary, often in the early morning or in the

evening to avoid evaporation by the sun.

Recycling

“gray”

water,

runoff

from household sinks and washing machines,

is best if the water is used quickly before bacteria collects

and if laundry

detergents

are

biodegradable

. Arid land-

scapers, using native and drought-resistant plant species in

conjunction with stone and concrete walkways and

mulch

create gardens that are not only aesthetically pleasing but

ecologically healthy.

[Stephanie Ocko]

ESOURCES

OOKS

Ball, K. Xeriscape Programs for Water Utilities. Denver: American Water

Works Association, 1990.

ERIODICALS

Ball, K., and G. O. Robinette. “The Water-Saving Garden Landscape.”

Country Journal (September/October 1990): 62–69.

Army Corps of Engineers

The United States Army Corps of Engineers, headquartered

in Washington, D.C., is the world’s largest engineering orga-

nization. The Corps was founded on June 16, 1775, the eve

of the Battle of Bunker Hill, as the Continental Army fought

cannon bombardments from British ships.

From early in the history of the Corps, the organiza-

tion has handled both military and civil engineering needs

of the United States. In earlier times those needs included

coastal fortifications and lighthouses, surveying and explor-

ing the frontier, construction of public buildings, snagging

and clearing river channels, and operating early national

parks such as Yellowstone. Under Corps’ direction, the Pan-

ama Canal and

St. Lawrence Seaway

were built, and the

Corps administered the Manhattan Project which led to the

development of the atomic bomb during World War II.

Today, the Corps of Engineers provides engineering

and related services in four areas: water and natural resource

management (civil works), military construction and sup-

port, engineering research and development, and support to

other government agencies.

In its military role, the Corps of Engineers provides

support on the battlefield, enhancing movement and opera-

tions of American forces while impeding or delaying enemy

actions. Corps engineers also plan, design, and supervise

construction of military facilities and operate and maintain

Army installations worldwide.

In its civil role, the Corps is responsible for the devel-

opment of the nation’s

water resources

and the operation

and maintenance of completed water resource projects.

Emerging engineering needs include renewal of infrastruc-

ture, management and control of

wetlands

development

and

ocean dumping

waste management

, including haz-

ardous and toxic waste,

solid waste

, and nuclear waste, and

disaster response and preparedness.

The Corps undertook the task of “unstraightening”

the Kissimmee River in south Florida. The river had been

straightened into a canal for flood control between 1961 and

1971, losing half its length and most of its marshes. In the

first reversal of a Corps’ project, the river is slated to regain

its curves. The restoration is due to be completed in 2005,

but already there have been an increase in the

flora

and

fauna

around the developed areas.

The Corps employees more than 48,000 military and

civilian members, has 13 regional headquarters, 39 district

offices, and four major laboratories and research centers

throughout the country.

[Linda Rehkopf]

ESOURCES

ERIODICALS

Duplaix, N. “Paying the Price.” National Geographic 178 (July 1990): 96.

Historical Highlights of the United States Army Engineers. Publication

EP 360-1-13. Washington, DC: U. S. Government Printing Office,

March, 1978.

Svante August Arrhenius (1859 –

1927)

Swedish chemist and physicist

Young Svante gave evidence of his intellectual brilliance at

an early age. He taught himself to read by the age of three

and learned to do arithmetic by watching his father keep

books for the estate of which he was in charge. Arrhenius

began school at the age of eight, when he entered the fifth-

grade class at the Cathedral School in Uppsala. After gradu-

ating in 1876, Arrhenius enrolled at the University of Up-

psala.

At Uppsala, Arrhenius concentrated on mathematics,

chemistry, and physics and passed the candidate’s examina-

tion for the bachelor’s degree in 1878. He then began a

graduate program in physics at Uppsala, but left after three

years of study. He was said to be dissatisfied with his physics

advisor, Tobias Thale

n, and felt no more enthusiasm for the

only advisor available in chemistry, Per Theodor Cleve. As

a result, he obtained permission to do his doctoral research

in absentia with the physicist Eric Edlund at the Physical

Institute of the Swedish Academy of Sciences in Stockholm.

Environmental Encyclopedia 3

Arsenic

The topic Arrhenius selected for his dissertation was

the electrical conductivity of solutions. In 1884 Arrhenius

submitted his thesis on this topic. In the thesis he hypothe-

sized that when salts are added to water, they break apart

into charged particles now known as ions. What was then

thought of as a molecule of sodium chloride, for example,

would dissociate into a charged sodium atom (a sodium

ion

)

and a charged

chlorine

atom (a chloride ion). The doctoral

committee that heard Arrhenius’s presentation in Uppsala

was totally unimpressed by his ideas. Among the objections

raised was the question of how electrically charged particles

could exist in water. In the end, the committee granted

Arrhenius his Ph.D., but with a score so low that he did

not qualify for a university teaching position.

Convinced that he was correct, Arrhenius had his

thesis printed and sent it to a number of physical chemists

on the continent, including Rudolf Clausius, Jacobus van’t

Hoff, and Wilhelm Ostwald. These men formed the nucleus

of a group of researchers working on problems that over-

lapped chemistry and physics, developing a new discipline

that would ultimately be known as physical chemistry. From

this group, Arrhenius received a much more encouraging

response than he had received from his doctoral committee.

In fact, Ostwald came to Uppsala in August 1884 to meet

Arrhenius and to offer him a job at Ostwald’s Polytechnikum

in Riga. Arrhenius was flattered by the offer and made plans

to leave for Riga, but eventually declined for two reasons.

First, his father was gravely ill (he died in 1885), and second,

the University of Uppsala decided at the last moment to

offer him a lectureship in physical chemistry.

Arrhenius remained at Uppsala only briefly, however,

as he was offered a travel grant from the Swedish Academy

of Sciences in 1886. The grant allowed him to spend the next

two years visiting major scientific laboratories in Europe,

working with Ostwald in Riga, Friedrich Kohlrausch in

rzburg, Ludwig Boltzmann in Graz, and van’t Hoff in

Amsterdam. After his return to Sweden, Arrhenius rejected

an offer from the University of Giessen, Germany, in 1891

in order to take a teaching job at the Technical University

in Stockholm. Four years later he was promoted to professor

of physics there. In 1903, during his tenure at the Technical

University, Arrhenius was awarded the Nobel Prize in chem-

istry for his work on the dissociation of electrolytes.

Arrhenius remained at the Technical University until

1905 when, declining an offer from the University of Berlin,

he became director of the physical chemistry division of the

Nobel Institute of the Swedish Academy of Sciences in

Stockholm. He continued his association with the Nobel

Institute until his death in Stockholm on October 2, 1927.

Although he was always be remembered best for his

work on dissociation, Arrhenius was a man of diverse inter-

ests. In the first decade of the twentieth century, for example,

he became especially interested in the application of physical

and chemical laws to biological phenomena. In 1908 Arrhen-

ius published a book entitled Worlds in the Making in which

he theorized about the transmission of life forms from planet

to planet in the universe by means of spores.

Arrhenius’s name has also surfaced in recent years

because of the work he did in the late 1890s on the

green-

house effect

. He theorized that

carbon dioxide

in the

atmosphere

has the ability to trap heat radiated from the

earth’s surface, causing a warming of the atmosphere.

Changes over time in the concentration of

carbon

dioxide

in the atmosphere would then, he suggested, explain major

climatic variations such as the glacial periods. In its broadest

outlines, the Arrhenius theory sounds similar to current spec-

ulations about

climate

changes resulting from global

warming.

Among the honors accorded Arrhenius in addition to

the Nobel Prize were the Davy Medal of the Royal Society

(1902), the first Willard Gibbs Medal of the Chicago section

of the American Chemical Society (1911), and the Faraday

Medal of the British Chemical Society (1914).

ESOURCES

OOKS

Arrhenius, Svante. Chemistry in Modern Life. Van Nostrand, 1925.

———. Theories of Solutions. Yale University Press, 1912.

———. Worlds in the Making: The Evolution of the Universe. Harper, 1908.

Fleck, George. “Svante Arrhenius.” In Nobel Laureates in Chemistry: 1901–

1992, edited by Laylin K. James. American Chemical Society and the

Chemical Heritage Foundation, 1993.

Arsenic

Arsenic is an element having an atomic number of 33 and

an atomic weight of 74.9216 that is listed by the U.S.

Envi-

ronmental Protection Agency

(EPA) as a hazardous sub-

stance (

Hazardous waste

numbers P010, P012) and as a

carcinogen

. The Merck Index states that the symptoms of

acute

poisoning

following arsenic ingestion are irritation of

the gastrointestinal tract, nausea, vomiting, and diarrhea that

can progress to shock and death. According to the 2001

Update Board on Environmental Studies and Toxicology,

such toxic presentations generally require weeks to months

of exposure to arsenic at high doses, as much as 0.04mg/

kg/day (0.02mg/lb/day). Furthermore, long-term, or chronic

poisoning can result in skin thickening, exfoliation, and hy-

perpigmentation. Continuing exposure also has been associ-

ated with development of herpes, peripheral neurological

manifestations, and degeneration of the liver and kidneys. Of

primary importance, however, is the association of chronic

arsenic exposure with increased risk of developing high blood

Environmental Encyclopedia 3

Arsenic-treated lumber

pressure, cardiovascular disease, and skin

cancer

, diseases

that are increasing public health concerns.

Variations of arsenic were used in everyday life. In the

early nineteenth century, it was discovered that a fungus,

Scopulariopsis brevicaulis, was eating away at the starches

found in certain forms of wallpaper. The fungus also altered

the arsenate dyes, changing them into trimethylarsine oxide,

which is further converted to the extremely toxic trimethylar-

sine gas. The gas was then released into the room, killing

the people who spent long amounts of time there, usually

sleeping. This process was discovered in 1897 but the gas

itself was not discovered and named until 1945.

Safe drinking water standards are regulated by the

EPA in the United States. In February 2002, the EPA

revised the former standard for acceptable levels of arsenic

in drinking water. The revision of the

Safe Drinking Water

Act

reduced the standard from 50

parts per billion

(ppb)

to 10 ppb of arsenic as the acceptable level for drinking

water. The regulation requires that all states must comply

with the new standard by January 2006. Sources of arsenic

contamination of drinking water include

erosion

of natural

deposits and run-off of waste from glassmaking and electron-

ics industries. Also, arsenic is used in insecticides and roden-

ticides, although much less widely than it once was due to

new information regarding its toxicity.

Arsenic-treated lumber

Arsenic-treated wood is wood that has been pressure-treated

with a

pesticide

containing inorganic

arsenic

(i.e., the arse-

nic compound does not contain

carbon

) to protect it from

dry rot,

fungi

, molds, termites, and other pests. The arsenic

can be a part of a CCA (chromated

copper

arsenate) chemi-

cal mixture consisting of three pesticidal compounds, copper,

chromate, and arsenic; the most commonly used type of

CCA contains 34% arsenic as arsenic pentoxide. Less com-

monly used wood preservatives containing arsenic include

the pesticide ACA (ammoniacal copper arsenate), which

contains ammonium, copper, and arsenic, and the pesticide

ACZA (ammoniacal copper zinc arsenate), which contains

ammonia, copper, zinc, and arsenic. In 1996, the United

States wood product industry used 30 million pounds of

arsenic, or half of all the arsenic produced worldwide.

Inorganic arsenic in CCA has been used since the

1940s. CAA is injected into wood through a process that uses

high pressure to saturate wood products with the

chemicals

Preserved wood products, such as utility poles, highway noise

barriers, sign posts, retaining walls, boat bulkheads, dock

pilings, and wood decking, are used in the construction,

railroad, and utilities industries. Historically CCA has been

the principal chemical used to treat wood for outdoor uses

around a home. Residential uses of arsenic-treated woods

include play structures, decks, picnic tables, gazebos, land-

scaping timbers, residential fencing, patios, and walkways/

boardwalks. After wood is pressure-treated with arsenic

compounds, residues of the preservatives can remain on the

surface. The initial residues wash off, but as the wood weath-

ers, new layers of treated wood and pesticides are exposed.

Arsenic is also present in paints that are used to cover the

cut ends of treated wood. Freshly arsenic-treated wood, if

not coated, has a greenish tint, which fades over time.

Arsenic is acutely toxic. Contact with arsenic may

cause irritation of the stomach, intestines, eyes, nose, and

skin, blood vessel damage, and reduced nerve function. In

addition, according to the

National Academy of Sciences

and the

National Research Council

, exposure to arsenic

increases the risk of human lung, bladder, and skin

cancer

over a lifetime and is suspected as a cause of kidney, prostate,

and nasal passage cancer. The National Academy of Sciences

and the Science Advisory Board of the United States

Envi-

ronmental Protection Agency

has also reported that arse-

nic may cause high blood pressure, cardiovascular disease,

and diabetes.

Arsenic may enter the body through the skin, by inges-

tion, or by inhalation. Ingestion occurs most frequently when

contaminated hands are put in the mouth, or when contami-

nated hands are used for eating food. Repeated exposure

will increase risks of adverse health effects. Splinters of wood

piercing the skin may also be a means of entry of arsenic

into the body, but the importance of this route has not been

well-studied.

The use of most pesticides containing arsenic had

been banned by the United States Environmental Protection

Agency, but in 1985 CCA was designated as a restricted-

use pesticide. However, CCA-treated wood products were

not regulated like the pesticides the wood products contained

because it was assumed that the pesticides would stay in the

wood. Unfortunately adequate information was not available

on whether arsenic is fixed in the wood permanently and

whether the wood product is safe. It is known that fixation

of the chemicals in the wood matrix is enhanced if the treated

wood is wrapped in tarps and stored for a sufficient length

of time, which varies with the temperature. For example, to

achieve fixation, the wood must be stored for 36 days in 50°

F (21° C) weather and for 12 days in 70° F (10° C) weather.

At 32° F., no fixation occurs.

However, research by the Florida Center for Solid

and Hazardous

Waste Management

and the Connecticut

Agricultural Experiment Station suggests that

leaching

arsenic into the soils or into surface water under CCA-

treated structures occurs at greater than safe levels. Florida

studies showed that arsenic was found in soils underneath

the eight pressure treated decks that were investigated. Of

Environmental Encyclopedia 3

Arsenic-treated lumber

73 samples taken, 61 samples had levels of arsenic higher

than the Florida clean up levels for industrial sites. One

sample had arsenic levels 300 times higher than the state’s

mandated clean up level.

Based on the potential for adverse health effects, the

United States Protection Agency announced in February

2002 that the use of consumer products made with CCA,

including play structures, decks, picnic tables, landscaping

timbers, patios, walkways, and board walks, will be phased

out voluntarily by the wood treating industry by December

31, 2003. Wood treated prior to December 31, 2003, can

still be used, and already-built structures using CCA-treated

wood and the

soil

surrounding the structures will not have

to be replaced or removed. As of August 2001, Switzerland,

Vietnam, and Indonesia had already banned the use of CCA-

treated wood, while Germany, Sweden, Denmark, Japan,

Australia

, and New Zealand restricted its use.

The United States Environmental Protection Agency

has issued cautionary recommendations to reduce consumer

exposure to arsenic-contaminated wood. Treated wood

should not be used where the preservative can become a

component of water, food or animal feed. Treated wood

should not be used where it may come into direct or indirect

contact with drinking water, except for uses where there is

incidental contact, such as docks and bridges. Treated wood

should not be used for cutting boards or counter tops, and

food should not be placed directly on treated wood. Children

and others should wash their hands after playing or working

outdoors, as arsenic may be swallowed from hand-to-mouth

activity. Children and pets should be kept out from under-

deck areas. Edible plants should not be grown near treated

decks or other structures contructed of treated wood. A

plastic liner should be placed on the inside of arsenic-treated

boards used to frame garden beds. Sawdust from treated

wood should not be used as animal bedding, and treated

boards should not be used to construct structures for storage

of animal feed or human food. Treated wood should not be

used in the construction of the parts of beehives that may

come into contact with honey.

Only wood that is visibly clean and free of surface

residues (e.g., wood that does not show signs of crystalliza-

tion or resin on its surface) should be used for patios, decks,

and walkways. Consumers working with arsenic-treated

wood should reduce their exposure by only sawing, sanding,

and machining treated wood outdoors and by wearing a dust

mask, goggles, and gloves when performing these types of

activities. They should also wash all exposed areas of their

bodies thoroughly with soap and water before eating, toilet-

ing, drinking, or using

tobacco

products. Work clothes

should be washed separately from other household clothing

before being worn again. Sawdust, scraps, and other con-

struction debris from arsenic-treated wood should not be

composted or used as

mulch

, but caught on tarps for disposal

off-site. Pressure-treated wood has an exemption from

haz-

ardous waste

regulations and can be disposed of in munici-

pal landfills without a permit. Pressure-treated wood should

not be burned in open fires or in stoves, fireplaces, or residen-

tial boilers, as both the

smoke

and the ash may contain

toxic chemicals. Treated wood from commercial or industrial

uses, such as from construction sites, may only be burned in

commercial or industrial incinerators or boilers in accordance

with state and federal regulations.

The United States Consumer Product Safety Com-

mission has recommended that playground equipment be

painted or sealed with a double coat of a penetrating, non-

toxic and non-slippery sealant (e.g., oil-based or semi-trans-

parent stains) every one or two years, depending upon wear

and

weathering

. However, available data are limited on

whether sealants will reduce the

migration

of wood preser-

vative chemicals from CCA-treated wood. Other potential

treatments include the use of polyurethane or other hard

lacquer, spar varnish, or pain. However, the use of film-

forming or non-penetrating stains are not recommended, as

subsequent flaking and peeling may later increase exposure to

preservatives in the wood. Structures constructed of arsenic-

treated wood should be inspected regularly for wood decay

and/or structural weakness. If the treated wood cracks and

exposes the interior of the wood is still structurally sound,

the affected area should be covered with a double coat of a

sealant.

Alternatives to the use of arsenic-treated lumber in-

clude the use of painted metal, stones or brick, recycled

plastic lumber, which may be all plastic or a composite of

plastic and wood fiber, lumber that has been treated with

an alternative pesticide ACQ (alkaline copper quaternary),

which does not contain arsenic, or untreated rot-resistant

wood such as cedar and redwood.

Arsenic compounds are referred to as arsenicals.

[Judith L. Sims]

ESOURCES

OOKS

Frankenberger, William T., Jr.Environmental Chemistry of Arsenic.???: Mar-

cel Dekker, 2001.

THER

Chromated Copper Arsenate (CCA) and Its Use as a Wood Preservative.Office

of Pesticide Programs, U.S. Environmental Protection Agency, Washing-

ton, DC, June 20, 2002. [cited June 25, 2002]. <http://www.epa.gov/

pesticides/citizens/1file.htm>.

Chromated Copper Arsenate (CCA) Wood: WMRC Library Reference

Guide.Waste Management & Research Center, Illinois Department of

Natural Resources, Champaign, IL, May 29, 2002. [cited June 25, 2002].

<http://www.wmrc.uiuc.edu/library/libraryinfo/refguides/ccawood.htm>.

Environmental Encyclopedia 3

Artesian well

A well that discharges water held in a confined

aquifer

Artesian

wells

are usually thought of as wells whose water

is free flowing at the land surface. However, there are many

other natural systems that can result in such wells. The

classic concept of artesian flow involves a basin with a water-

intake area above the level of

groundwater discharge

These systems can include stabilized sand

dunes

; fractured

zones along bedrock faults; horizontally layered rock forma-

tions; and the intermixing of

permeable

and impermeable

materials along glacial margins.

Asbestos

Asbestos is a fibrous mineral silicate, occurring in numerous

forms, of which amosite [Fe

(Si

)(OH)

] has been

shown to cause mesothelioma, squamous cell carcinoma and

adenocarcinoma of the lung after long exposure times. This

substance has been listed by the

Environmental Protection

Agency

(EPA). Lung

cancer

is most likely to occur in

those individuals who are exposed to high air-borne doses

of asbestos and who also

smoke

. The pathogenic potential

of asbestos appears to be related to its aspect ratio (length-

to-diameter ratio), size (particles less than 2 micrometers in

length are the most hazardous), and to its surface reactivity.

Asbestos exposure causes thickening of and calcified

plaques on the lining of the chest cavity. When inhaled it

forms “asbestos bodies” in the lungs, yellowish-brown parti-

cles created by reactions between the fibers and lung tissue.

This disease was first described by W. E. Cooke in 1921 and

given the name

asbestosis

. The

latency

period is generally

longer than 20 years—the heavier the exposure, the more

likely and the earlier is the onset of the disease. In 1935

an association between asbestos and cancer was noted by

Kenneth M. Lynch. However, it was not until 1960 that

Christopher Wagner demonstrated a particularly lethal asso-

ciation between cancer of the lining of the lungs and asbestos.

By 1973 the

National Institute of Occupational Safety

and Health

recommended adoption of an occupational stan-

dard of two asbestos fibers per cubic centimeter of air.

During this time, many cases of lung cancer began to

surface, especially among asbestos workers who had been

employed in shipbuilding during World War II. The com-

pany most impacted by lawsuits was the Manville Corpora-

tion which had been the supplier to the United States gov-

ernment. Manville Corporation eventually sought Title 11

Federal Bankruptcy protection as a result of these law suits.

More recently, the Reserve Mining Company, a taco-

nite (iron ore) mining operation in

Silver Bay

, Minnesota,

was involved in litigation over the dumping of

tailings

(wastes) from their operations into Lake Superior. These

tailings contained amositic asbestos particles which appeared

to migrate into the Duluth, Minnesota water supply. In an

extended law suit, Reserve Mining Company was ordered

to shut down their operations. One controversial question

raised during the legal action was whether cancer could be

caused by from drinking water containing asbestos fibers.

In other cancer cases related to asbestos, the asbestos was

inhaled rather than ingested. Federal courts held that there

is reasonable cause to believe that asbestos in food and drink

is dangerous—even in small quantities—and ordered Re-

serve Mining to stop dumping tailings in the lake.

A significant industry has developed for removing as-

bestos materials from private and public buildings as a result

of the tight standards placed on asbestos concentrations by

the

Occupational Safety and Health Administration

.At

one time, many steel construction materials, especially hori-

zontal beams, were sprayed with asbestos to enhance their

resistance

to fires. Wherever these materials are now ex-

posed to

ambient air

in buildings, they have the potential

to create a hazardous condition. The asbestos must either

be covered or removed, and another insulating material sub-

stituted as great cost. Removal, however, causes its own

problems, releasing high concentrations of fibers into the

air. Many experts regard covering asbestos in place with a

plastic covering to be the best option in most cases. What

was once considered a life-saving material for its flame re-

tardancy, now has become a hazardous substance which must

be removed and sequestered in sites specially certified for

holding asbestos building materials.

[Malcolm T. Hepworth]

ESOURCES

OOKS

Bartlett, R. V. The Reserve Mining Controversy: Science, Technology, and

Environmental Quality. Bloomington: Indiana University Press, 1980.

Brodeur, P. Asbestos and Enzymes. New York: Ballantine Books, 1972.

Asbestos removal

Asbestos

is a naturally occurring mineral, used by humans

since ancient times but not extensively until the 1940s. After

World War II and for the next 30 years, it was widely

used as a construction material in schools and other public

buildings. The United States

Environmental Protection

Agency

(EPA) estimates that there are asbestos-containing

materials in most of the primary and secondary schools as

well as in most public and commercial buildings in the

nation. It is estimated that 27 million Americans had signifi-

cant occupational exposure to asbestos between 1940 and

1980. Asbestos has been popular because it is readily avail-

Environmental Encyclopedia 3

Asbestos removal

able, low in cost, and has very useful properties. It does

not burn, conducts heat and electricity poorly, strengthens

concrete products into which it is incorporated, and is resis-

tant to chemical corrosion. It has been used in building

materials as a thermal and electrical insulator and has been

sprayed on steel beams in buildings for protection from heat

in fires. Asbestos has also been used as an acoustical plaster.

In 1984, an EPA survey found that approximately 66% of

those buildings containing asbestos had damaged asbestos-

containing materials in them. The EPA distinguishes be-

tween two types of asbestos damage. If the material, when

dry, can be crumbled by hand pressure, it is called “friable.”

If not, it is called “non-friable.” The friable form is much

more likely to release dangerous fibers into the air. Fluffy,

spray-applied asbestos fireproofing material is an example

of friable asbestos. Vinyl-asbestos floor tile is an example of

a non-friable material, although it too can release fibers

when sanded, sawed, or aggressively disturbed.

Growing recognition that asbestos dust is a dangerous

air pollutant has led to government regulation of its

use and provisions for removal of asbestos and asbestos-

containing products from dwellings, schools, and the work-

place. In the United States, the Federal Government has

taken steps to prevent unnecessary exposure to asbestos

since the 1970s. Six different agencies have authority to

regulate some aspect of asbestos use in the United States.

The authorized agencies are the EPA,

Occupational

Safety and Health Administration

(OSHA),

Food and

Drug Administration

, Consumer Product Safety Commis-

sion, Department of

Transportation

, and the Mine Safety

and Health Administration.

The EPA has authority to oversee use of asbestos

in commerce and has developed standards controlling its

handling and use. It administers the Asbestos Hazard Emer-

gency Response Act (AHERA) of 1986 that regulates asbes-

tos in schools. The Act prescribes management practices

and abatement standards for both public and private schools,

and it follows a 1979 rule that launched a technical assistance

program to aid schools in efforts to identify asbestos-con-

taining materials. AHERA requires schools to develop a

management plan concerning their asbestos-containing ma-

terials. Schools must appoint an asbestos manager to be

responsible for a number of activities, which include imple-

menting a plan to manage asbestos-containing building ma-

terials and ensuring compliance with federal asbestos regula-

tions. AHERA also requires local officials to carry out

inspections to identify asbestos-containing materials in pub-

lic and private elementary and secondary schools, and to

comply with AHERA’s record keeping requirements. The

emphasis on asbestos abatement in schools arises from the

recognition that children are especially vulnerable to a viru-

lent form of lung

cancer

called mesothelioma caused by

asbestos.

The EPA also administers the Asbestos School Haz-

ard Abatement Reauthorization Act (ASHARA) of 1990

which requires that accredited personnel be used to work

with asbestos in schools and in public and commercial build-

ings. The Act sets training requirements for asbestos profes-

sionals, contractors, and abatement workers. It is estimated

that 733,000 public buildings in the United States (about

20% of the total) have some type of defective or deteriorating

asbestos-containing material in them. Asbestos is frequently

found in pipe and boiler insulation, caulking putties, joint

compounds, linoleum, acoustical plaster, ceiling tiles, and

other building components. ASHARA does not require

owners of public and commercial buildings to conduct in-

spections for asbestos-containing materials, but it does re-

quire owners who opt for inspections to use accredited in-

spectors. To obtain accreditation, asbestos workers must take

a 4-day, 32-hour EPA-approved training course covering

topics such as potential health effects of asbestos exposure,

the use of personal protective equipment, and up-to-date

work practices. Detached single-family homes and residen-

tial apartment buildings of fewer than 10 units are not cov-

ered by the Act.

The EPA is also responsible for the 1989 Asbestos

Ban and Phase out Rule that was partially overturned by a

Federal Court in 1991. Originally, the ban applied to a

wide variety of asbestos-containing products including roof

coatings, floor tile, brake pads and linings, and pipeline wrap.

Although these products and many others were removed

from the ban, it still applies to all new uses of asbestos. The

ban remains in effect for the sprayed-on asbestos fireproofing

that has been prohibited since 1978.

Individual home owners may seek advice from local

health officials concerning potential asbestos problems in or

on their dwelling. State agencies often publish pamphlets

or brochures that offer help in identifying and correcting

problems. Common places to find asbestos in homes include

wall, ceiling, and pipe insulation in structures built between

1930 and 1950, and in sheet vinyl, vinyl tile, and vinyl

adhesive used in floor coverings. These materials are consid-

ered safe, and need not be removed unless they are damaged

or disturbed. Wall and ceiling surfaces may contain troweled-

on or sprayed-on surface material containing asbestos. If the

material is hard, firmly attached, and does not produce a

powder or dust when hand pressure is applied, it is probably

not hazardous. On the exterior of many older homes, a

cement asbestos board called Transite™ has been used

as sheet or lap siding and has sometimes been shaped to

mimic wood shingles. This material, too, is considered safe

unless it has been damaged or disturbed. Other asbestos-

containing objects in the home include older electrical lamp

Environmental Encyclopedia 3

Asbestos removal

Asbestos removal from a building. (Photograph by Eugene Smith. Black Star Publishing Company Inc. Reproduced by permission.)

socket collars, switch and receptacle boxes, fuse boxes, and

old-fashioned “knob and tube” wiring. Asbestos is found in

insulation blankets of older ovens, dishwashers, water heat-

ers, and freezers. These items need not be removed if they

are intact and not damaged.

There is no safe and reliable way for an untrained

individual to identify asbestos except to have it analyzed

by a competent testing laboratory. In taking a sample for

laboratory analysis, it is important that one not release

fibers into the air or get them into one’s clothes. To

avoid this, it is often helpful to spray the material with

a fine mist of water before sampling. The material should

not be disturbed more than necessary, and the sample for

testing should be enclosed in a sealed plastic or glass vial.

If asbestos-containing materials must be removed, they

should not be placed with other household trash. Local

health officials should be contacted for instructions on

safe disposal.

Most public buildings with asbestos-containing mate-

rials do not pose an immediate risk to the occupants. As

long as the asbestos is sealed and not releasing fibers, there

is no health threat. Since asbestos is easily disturbed during

building alterations, routine maintenance, and even normal

use, it is wise to take precautions to control or eliminate

exposure. When asbestos-containing objects are identified,

removal, encapsulation, and containment may be used to

protect occupants. If the objects are damaged or in poor

condition, they should be removed. Proper removal tech-

niques must be strictly followed to avoid spreading contami-

nation. Encapsulation is accomplished by sealing objects

with an approved chemical sealant. Containment can be

accomplished by constructing suitable physical barriers

around the objects to contain any fibers that may be released.

Air monitoring and inspection of buildings with asbestos-

containing material should be performed regularly to be

sure that fiber releases have not occurred. Maintenance and

operations crews should be notified of an asbestos threat in

their building, and they should be taught proper precautions

to avoid accidental disturbance.

The Occupational Safety and Health Administration

(OSHA), under the jurisdiction of the United States

Department of Labor, is charged with protection of worker

safety on the job. OSHA estimates that 1.3 million

employees in construction and general industry face signifi-