Environmental Encyclopedia

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Environmental Encyclopedia 3

Environmental estrogens

These wide-ranging examples are typical of the solu-

tions which are being developed by a new generation of

technically-trained individuals. In an increasingly populated

and industrialized world, environmental engineers will con-

tinue to play a pivotal role in devising technologies needed

to minimize the impact of humans on the earth’s resources.

[Malcolm T. Hepworth]

ESOURCES

OOKS

American Academy of Environmental Engineers. AAEE Bylaws. Annapo-

lis, Maryland: 1990.

Cartledge, B., ed. Monitoring the Environment. New York: Oxford Univer-

sity Press, 1992.

Corbitt, Robert A.: Standard Handbook of Environmental Engineering. New

York: McGraw-Hill, 1989.

Jacobsen, J., ed. Human Impact on the Environment: Ancient Roots, Current

Challenges. Boulder, CO: Westview Press, 1992.

ERIODICALS

Crucil, C. “Environmentally Sound Buildings Now Within Reach.” Alterna-

tives 19 (January-February 1993): 9-10.

THER

Gilbertson, W. E. “Environmental Quality Goals and Challenges.” Proceed-

ings of the Third National Environmental Engineering Education Conference

edited by P. W. Purdon. American Academy of Environmental Engineers

and the Association of Environmental Engineering Professors, Drexel Uni-

versity, 1973.

Environmental estrogens

The United States

Environmental Protection Agency

(

EPA

) defines an environmental endocrine disruptor—the

term the Agency uses for environmental estrogens—as “an

exogenous agent that interferes with the synthesis, secretion,

transport, binding, action, or elimination of natural hor-

mones in the body that are responsible for the maintenance of

homeostasis

, reproduction, development, and/or behavior.”

Dr. Theo Colborn, a zoologist and senior scientist with the

World Wildlife Fund

, and the person most credited with

raising national awareness of the issue, describes these

chem-

icals

as “hand-me-down poisons” that are passed from

mothers to offspring and may be linked to a wide range of

adverse effects, including low sperm counts, infertility, geni-

tal deformities, breast and prostate

cancer

, neurological dis-

orders in children such as hyperactivity and attention deficits,

and developmental and reproductive disorders in

wildlife

Colborn discusses these effects in her 1996 book, Our Stolen

Future—co-authored with Dianne Dumanoski and John Pe-

terson Myers—which asks: “Are we threatening our fertility,

intelligence, and survival?” Some other names used for the

same class of chemicals are hormone disruptors, estrogen

487

mimics, endocrine disrupting chemicals, and endocrine

modulators.

While EPA takes the position that it is “aware of and

concerned” about data indicating that exposure to environ-

mental

endocrine disruptors

may cause adverse impacts

on human health and the

environment

, the Agency at

present does not consider endocrine disruption to be “an

adverse endpoint per se.” Rather, it is “a mode or mechanism

of action potentially leading to other outcomes"—such as

the health effects Colborn described drawing from extensive

research of numerous scientists—but, in EPA’s view, the

link to human health effects remains an unproven hypothesis.

For Colborn and a significant number of other scientists,

however, enough is known to support prompt and far-reach-

ing action to reduce exposures from these chemicals and

myriad products that are manufactured using them. Foods,

plastic packaging, and pesticides are among the sources of

exposure Colborn raises concerns about in her book.

Ultimately, the environmental estrogens issue is about

whether these chemicals are present in the environment at

high enough levels to disrupt the normal functioning of

wildlife and human endocrine systems and thereby cause

harmful effects. The endocrine system is one of at least three

important regulatory systems in humans and other animals

(the nervous and immune systems are the other two) and

includes such endocrine glands as the pituitary, thyroid,

pancreas, adrenal, and the male and female gonads, or testes

and ovaries. These glands secrete hormones into the blood-

stream where they travel in very small concentrations and

bind to specific sites called “cell receptors” in target tissues

and organs. The hormones affect development, reproduc-

tion, and other bodily functions. The term “endocrine dis-

ruptors” includes not only estrogens but also antiandrogens

and other agents that act on the endocrine system.

The question of whether environmental endocrine dis-

ruptors may be causing effects in humans has arisen over

the past decade based on a growing body of evidence about

effects in wildlife exposed to dichlorodiphenyl-trichlore-

thane (DDT),

polychlorinated biphenyls

(PCBs), and

other chemicals. For instance, field studies have proven that

tributyltin (TBT), which is used as an antifouling paint on

ships, can cause “imposex” in female snails, which are now

commonly found with male genitalia, including a penis and

vas deferens, the sperm-transporting tube. TBT has also

been shown to cause decreased egg production by the peri-

winkle (Littorina littorea). As early as 1985, concerns arose

among scientists and the public in the United Kingdom over

the effects of synthetic estrogens from birth control pills

entering rivers, a concern that was heightened when anglers

reported catching fish with both male and female character-

istics. Other studies have found

Great Lakes salmon

invariably have thyroids that were abnormal in appearance,

Environmental Encyclopedia 3

Environmental estrogens

even when there were no overt goiters. Herring gulls (Larus

argentatus) throughout the Great Lakes have also been found

with enlarged thyroids. In the case of the salmon and gulls,

no agent has been determined to be causing these effects.

But other studies have linked DDT exposure in the Great

Lakes to eggshell thinning and breakage among bald eagles

and other birds. In Lake Apopka, Florida, male alligators

(Alligator mississippiensis) exposed to a mixture of dicofol,

DDT, and dichlorodiphenyldichloroethylene (DDE) have

been “demasculinized,” with phalluses one-half to one-

fourth the normal size. Red-eared turtles (Trachemys scripta)

in the lake have also been demasculinized. One 1988 study

reported that four of 15 female black bears (Ursus americanus)

and one of four female brown bears (Ursus arctos) had, to

varying degrees, male sex organs. These and nearly 300 other

peer-reviewed studies have led EPA—in conjunction with

the multi-agency White House Committee on Environment

and Natural Resources—to develop a “framework for plan-

ning” and an extensive research agenda to answer questions

about the effects of endocrine disruptors. The goal is to

better understand the potential effects of such chemicals on

human beings before implementing regulatory actions.

The federal research agenda has been evolving through

a series of workshops. As early as 1979, the

National Insti-

tute of Environmental Health Sciences

(NIEHS), based

in Research Triangle Park, North Carolina, held an “Estro-

gens in the Environment” conference to evaluate the chemi-

cal properties and diverse structures among environmental

estrogens. NIEHS held a second conference in 1985 that

addressed numerous potential toxicological and biological

effects from exposure to these chemicals. NIEHS’s third

conference, held in 1994, focused on detrimental effects in

wildlife. At an April 1995 EPA-sponsored workshop on

“Research Needs for the

Risk Assessment

of Health and

Environmental Effects of Endocrine Disruptors,” a number

of critical research questions were discussed: What do we

know about the carcinogenic effects of endocrine-disrupting

agents in humans and wildlife? What are the research needs

in this area, including the highest priority research needs?

Similar questions were discussed for reproductive effects,

neurological effects, immunological effects, and a variety of

risk assessment issues. Drawing on the preceding conferences

and workshops, in February 1997 EPA issued a Special Re-

port on Environmental Endocrine Disruption: An Effects Assess-

ment and Analysis that recommended key research needs to

better understand how environmental endocrine disruptors

may be causing the variety of specific effects in human beings

and wildlife hypothesized by some scientists. For instance,

male reproductive research should include tests that evaluate

both the quantity and quality of sperm produced. Further-

more, when testing the endocrine-disrupting potential of

chemicals, it is important to test for both estrogenic and

488

antiandrogenic activity because new data suggest that it is

possible the latter—antiandrogenic activity—not estrogenic

activity, is causing male reproductive effects. In the area of

ecological research, EPA’s special report highlighted the

need for research on such issues as what chemicals or class

of chemicals can be considered genuine endocrine disruptors

and what dose is needed to cause an effect.

Even before environmental estrogens received a place

on the federal environmental agenda as a priority concern,

Colborn and other scientists first met in July 1991 in Racine,

Wisconsin, to discuss their misgivings about the prevalence

of estrogenic chemicals in the environment. From that meet-

ing came the landmark “Wingspread Consensus Statement”

of 21 leading researchers. The statement asserted that the

scientists were certain that a large number of human-made

chemicals that have been released into the environment, as

well as a few natural ones, “have the potential to disrupt the

endocrine system of animals, including humans,” and that

many wildlife populations are already affected by these

chemicals. Furthermore, the scientists expressed certainty

that the effects may be entirely different in the embryo,

fetus, or perinatal organisms than in the adult; that effects

are more often manifested in offspring than in exposed par-

ents; that the timing of exposure in the developing organism

is crucial; and that, while embryonic development is the

critical exposure period, “obvious manifestations may not

occur until maturity.” Besides these and other “certain” con-

clusions, the scientists estimated with confidence that “some

of the developmental impairments reported in humans today

are seen in adult offspring of parents exposed to synthetic

hormone disruptors (agonists and antagonists) released in

the environment” and that “unless the environmental load

of synthetic hormone disruptors is abated and controlled,

large scale dysfunction at the population level is possible.”

The Wingspread Statement included numerous other con-

sensus views on what models predict and the judgment of

the group on the need for much greater research and a

comprehensive inventory of these chemicals.

The Food Quality Protection Act of 1996 (FQPA)

and the

Safe Drinking Water Act

Amendments of 1996

require EPA to develop a screening program to determine

whether pesticides or other substances cause effects in hu-

mans similar to effects produced by naturally occurring estro-

gens and other endocrine effects. The FQPA requires

pesti-

cide

registrants to test their products for such effects and

submit reports, and it requires that registrations be sus-

pended if registrants fail to comply. Besides the EPA screen-

ing program, the

United Nations Environment Pro-

gramme

is pursuing a multinational effort to manage

“persistent organic pollutants,” including DDT and PCBs,

which, though banned in the United States, are still used

elsewhere and can persist in the environment and be trans-

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Environmental ethics

ported long-distance. In February 1997, Illinois became the

first state to issue a strategy for endocrine disruptors that

requires every Illinois EPA program to assess its current

activities affecting these chemicals and to begin monitoring

a list of known, probable, and suspected chemicals in case

further action is needed in the future.

[David Clarke]

ESOURCES

OOKS

Colborn, T., D. Dumanoski, and J. P. Myers. Our Stolen Future. New

York: Penguin Books, 1996.

“Estrogens in the Environment.” Environmental Health Perspectives Supple-

ments 3, supplement 7. North Carolina: Research Triangle Park, 1995.

National Science and Technology Council. Committee on Environment

and Natural Resources. The Health and Ecological Effects of Endocrine Dis-

rupting Chemicals, A Framework for Planning. Washington, D.C., 1996.

U.S. Environmental Protection Agency. Special Report on Environmental

Endocrine Disruption: An Effects Assessment and Analysis. (EPA/630/R-96/

012). Washington, D.C.: GPO, 1997.

Environmental ethics

Ethics is a branch of philosophy that deals with morals and

values. Environmental ethics refers to the moral relationships

between humans and the natural world. It addresses such

questions as, do humans have obligations or responsibilities

toward the natural world, and if so, how are those responsi-

bilities balanced against human needs and interests? Are

some interests more important than others?

Efforts to answer such ethical questions have led to

the development of a number of schools of ethical thought.

One of these is

utilitarianism

, a philosophy associated with

the English eccentric Jeremy Bentham and later modified

by his godson John Stuart Mill. In its most basic terms,

utilitarianism holds that an action is morally right if it pro-

duces the greatest good for the greatest number of people.

The early environmentalist

Gifford Pinchot

was inspired by

utilitarian principles and applied them to

conservation

Pinchot proposed that the purpose of conservation is to

protect

natural resources

to produce “the greatest good

for the greatest number for the longest time.” Although

utilitarianism is a simple, practical approach to human moral

dilemmas, it can also be used to justify reprehensible actions.

For example, in the nineteenth century many white Ameri-

cans believed that the extermination of native peoples and

the appropriation of their land was the right thing to do.

However, most would now conclude that the good derived

by white Americans from these actions does not justify the

genocide and displacement of native peoples.

The tenets of utilitarian philosophy are presented in

terms of human values and benefits, a clearly anthropocentric

489

world view. Many philosophers argue that only humans are

capable of acting morally and of accepting responsibility for

their actions. Not all humans, however, have this capacity

to be moral agents. Children, the mentally ill, and others are

not regarded as moral agents, but, rather, as moral subjects.

However, they still have rights of their own—rights that

moral agents have an obligation to respect. In this context,

moral agents have

intrinsic value

independent of the beliefs

or interests of others.

Although humans have long recognized the value of

non-living objects, such as machines, minerals, or rivers, the

value of these objects is seen in terms of money, aesthetics,

cultural significance, etc. The important distinction is that

these objects are useful or inspiring to some person—they

are not ends in themselves but are means to some other end.

Philosophers term this instrumental value, since these objects

are the instruments for the satisfaction of some other moral

agent. This philosophy has also been applied to living things,

such as domestic animals. These animals have often been

treated as simply the means to some humanly-desired end

without any inherent rights or value of their own.

Aldo Leopold

, in his famous essay on environmental

ethics, pointed out that not all humans have been considered

to have inherent worth and intrinsic rights. As examples

he points to children, women, foreigners, and indigenous

peoples—all of whom were once regarded as less than full

persons; as objects or the property of an owner who could

do with them whatever he wished. Most civilized societies

now recognize that all humans have intrinsic rights, and, in

fact, these intrinsic rights have also been extended to include

such entities as corporations, municipalities, and nations.

Many environmental philosophers argue that we must

also extend recognition of inherent worth to all other compo-

nents of the natural world, both living and non-living. In

their opinion, our anthropocentric view, which considers

components of the natural world to be valuable only as

the means to some human end, is the primary cause of

environmental degradation

. As an alternative, they pro-

pose a biocentric view which gives inherent value to all the

natural world regardless of its potential for human use.

Paul Taylor outlines four basic tenets of biocentrism

in his book, Respect for Nature. These are: 1) Humans are

members of earth’s living community in the same way and

on the same terms as all other living things; 2) Humans and

other

species

are interdependent; 3) Each organism is a

unique individual pursuing its own good in its own way; 4)

Humans are not inherently superior to other living things.

These tenets underlie the philosophy developed by Norwe-

gian Arne Naess known as

deep ecology

From this biocentric philosophy Paul Taylor devel-

oped three principles of ethical conduct: 1) Do not harm

any natural entity that has a good of its own; 2) Do not try

Environmental Encyclopedia 3

Environmental health

to manipulate, control, modify, manage or interfere with the

normal functioning of natural ecosystems, biotic communi-

ties, or individual wild organisms; 3) Do not deceive or

mislead any animal capable of being deceived or misled.

These principles led Professor Taylor to call for an end to

hunting

, fishing and

trapping

, to espouse

vegetarianism

and to seek the exclusion of human activities from

wilder-

ness

areas. However, Professor Taylor did not extend intrin-

sic rights to non-living natural objects, and he assigned only

limited rights to plants and domestic animals. Others argue

that all natural objects, living or not, have rights.

Regardless of the appeal that certain environmental

philosophies may have in the abstract, it is clear that humans

must make use of the natural world if they are to survive.

They must eat other organisms and compete with them for

all the essentials of life. Humans seek to control or eliminate

harmful plants or animals. How is this intervention in the

natural world justified? Stewardship is a principle that phi-

losophers use the justify such interference. Stewardship holds

that humans have a unique responsibility to care for domestic

plants and animals and all other components of the natural

world. In this view, humans, their knowledge, and the prod-

ucts of their intellect are an essential part of the natural

world, neither external to it nor superfluous. Stewardship

calls for humans to respect and cooperate with

nature

achieve the greatest good. Because of their superior intellect,

humans can improve the world and make it a better place,

but only if they see themselves as an integral part of it.

Ethical dilemmas arise when two different courses of

action each have valid ethical underpinnings. A classic ethical

dilemma occurs when any course of action taken will cause

harm, either to oneself or to others. Another sort of dilemma

arises when two parties have equally valid, but incompatible,

ethical interests. To resolve such competing ethical claims

Paul Taylor suggests five guidelines: 1) it is usually permissi-

ble for moral agents to defend themselves; 2) basic interests,

those interests necessary for survival, take precedence over

other interests; 3) when basic interests are in conflict, the

least amount of harm should be done to all parties involved;

4) whenever possible, the disadvantages resulting from com-

peting claims should be borne equally by all parties; 5) the

greater the harm done to a moral agent, the great is the

compensation required.

Ecofeminists do not find that utilitarianism, bio-

centrism or stewardship provide adequate direction to solve

environmental problems or to guide moral actions. In their

view, these philosophies come out of a patriarchal system

based on domination—of women, children, minorities and

nature. As an alternative, ecofeminists suggest a pluralistic,

relationship-oriented approach to human interactions with

the

environment

Ecofeminism

is concernedwith nurturing,

reciprocity, and connectedness, rather than with rights, re-

490

sponsibilities, and ownership. It challenges humans to see

themselves as related to others and to nature. Out of these

connections, then, will flow ethical interactions among indi-

viduals and with the natural world. See also Animal rights;

Bioregionalism; Callicott, J. Baird; Ecojustice; Environmen-

tal racism; Environmentalism; Future generations; Human-

ism; Intergenerational justice; Land stewardship; Rolston,

Holmes; Speciesism

[Christine B. Jeryan]

ESOURCES

OOKS

Devall, B., and G. Sessions. Deep Ecology. Layton, UT: Gibbs M.

Smith, 1985.

Odell, R. Environmental Awakening: The New Revolution to Protect the

Earth. Cambridge, MA: Ballinger, 1980.

Olson, S. Reflections From the North Country. New York: Knopf, 1980.

Plant, J. Healing the Wounds: The Promise of Ecofeminism. Santa Cruz, CA:

New Society Publishers, 1989.

Rolston, H. Environmental Ethics. Philadelphia, Temple University

Press, 1988.

Taylor, P. Respect for Nature. Princeton, NJ: Princeton University Press,

1986.

Environmental health

Environmental health is concerned with the medical effects

chemicals

, pathogenic (disease-causing) organisms, or

physical factors in our

environment

. Because our environ-

ment affects nearly every aspect of our lives in some way or

other, environmental health is related to virtually every

branch of medical science. The special focus of this disci-

pline, however, tends to be health effects of polluted air and

water, contaminated food, and toxic or hazardous materials

in our environment. Concerns about these issues makes envi-

ronmental health one of the most compelling reasons to be

interested in

environmental science

For a majority of humans, the most immediate envi-

ronmental health threat has always been pathogenic organ-

isms. Improved

sanitation

, nutrition, and modern medicine

in the industrialized countries have reduced or eliminated

many of the

communicable diseases

that once threatened

us. But for people in the

less developed countries

where

nearly 80% of the world’s population lives, bacteria, viruses,

fungi

parasites

, worms, flukes, and other infectious agents

remain major causes of illness and death. Hundreds of mil-

lions of people suffer from major diseases such as

malaria

gastrointestinal infections (diarrhea, dysentery,

cholera

), tu-

berculosis, influenza, and pneumonia spread through the air,

water, or food. Many of these terrible diseases could be

eliminated or greatly reduced by a cleaner environment, inex-

pensive dietary supplements, and better medical care.

Environmental Encyclopedia 3

Environmental health

For the billion or so richest people in the world—

including most of the population of the United States and

Canada—diseases related to lifestyle or longevity tend to be

much greater threats than more conventional environmental

concerns such as dirty water or polluted air. Heart attacks,

strokes,

cancer

, depression and hypertension, traffic acci-

dents, trauma, and

AIDS

lead as causes of sickness and death

in wealthy countries. These diseases are becoming increas-

ingly common in the developing world as people live longer,

exercise less, eat a richer diet, and use more drugs,

tobacco

and alcohol. Epidemiologists predict that by the middle of

the next century, these diseases of affluence will be leading

causes of sickness and death everywhere.

Although a relatively minor cause of illness compared

to the factors above, toxic or hazardous synthetic chemicals

in the environment are becoming an increasing source of

concern as industry uses more and more exotic materials to

manufacture the goods we all purchase. There are many of

these compounds to worry about. Somewhere around five

million different chemical substances are known, about

100,000 are used in commercial quantities, and about 10,000

new ones are discovered or invented each year. Few of these

materials have been thoroughly tested for toxicity. Further-

more, the process of predicting what our chances of exposure

and potential harm might be from those re-leased into the

environment remains highly controversial.

Toxins

are poi-

sonous, which means that they react specifically with cellular

components or interfere with unique physiological processes.

A particular chemical may be toxic to one organism but not

another, or dangerous in one type of exposure but not others.

Because of this specificity, they may be harmful even in very

dilute concentrations. Ricin, for instance, is a protein found

in castor beans and one of the most toxic materials known.

Three hundred picograms (trillionths of a gram) injected

intravenously is enough to kill an average mouse. A single

molecule can kill an individual cell. If humans were as sensi-

tive as mice, a few teaspoons of this compound, divided

evenly and distributed uniformly could kill everyone in the

world. By the way, this points out that not all toxins are

produced by industry. Many natural products are highly

toxic.

Toxins that have chronic (long-lasting) or irreversible

effects are of special concern. Among some important exam-

ples are neurotoxins (attack nerve cells), mutagens (cause

genetic damage), teratogens (result in

birth defects

), and

carcinogens (cause cancer). Many pesticides and metals such

mercury

lead

, and chromium are neurotoxins. Loss of

even a few critical neurons can be highly noticeable or may

even be lethal making this category of great importance.

Chemicals or physical factors such as radiation that damage

genetic material can harm not only cells produced in the

491

exposed individual, but also the offspring of those individuals

as well.

Among the most dread characteristics of all these

chronic environmental health threats are that the initial ex-

posure may be so small or have results so unnoticeable that

the victim doesn’t even know that anything has happened

until years later. Furthermore the results may be catastrophic

and irreversible once they do appear. These are among our

worst fears and are powerful reasons that we are so apprehen-

sive about environmental contaminants. There may be no

exposure—no matter how small—of some chemicals that is

absolutely safe. Because of these fears, we often demand

absolute protection from some of the most dread contami-

nants. Unfortunately, this may not be possible. There may

be no way to insure that we are never exposed to any amount

of some hazards. It may be that our only recourse is to ask

how we can reduce our exposure or mitigate the conse-

quences of that exposure.

In spite of the foregoing discussion of the dangers of

chronic effects

from minute exposures to certain materials

or factors, not all pollutants are equally dangerous nor is

every exposure an unacceptable risk. Our fear of unknown

and unfamiliar industrial chemicals can lead to hysterical

demands for zero exposure to risks. The fact is that life is

risky. Furthermore, some materials are extremely toxic while

others are only moderately or even slightly so.

This is expressed in the adage of the German physi-

cian, Paracelsus, who said in 1540 that “The dose makes

the poison.” It has become a basic principle of toxicology

that nearly everything is toxic at some concentration but

most materials have some lower level at which they present

an insignificant risk. Sodium chloride (table salt), for in-

stance, is essential for human life in small doses. If you were

forced to eat a kilogram all at once, however, it would make

you very sick. A similar amount injected all at once into

your blood stream would be lethal.

How a material is delivered—at what rate, through

which route of entry, in what form—is often as important

as what the material is. The movement, distribution, and

fate of materials in the environment are important aspects of

environmental health. Solubility is one of the most important

characteristics in deter- mining how, when, and where a

material will travel through the environment and into our

bodies. Chemicals that are water soluble move more rapidly

and extensively but also are easier to wash off, excrete, or

eliminate. Oil or fat soluble chemicals may not move through

the environment as easily as water-soluble materials but may

penetrate very efficiently through the skin and into tissues

and organs. They also may be more likely to be concentrated

and stored permanently in fat deposits in the body.

The most common route of entry into the body for

many materials is through ingestion and

absorption

in the

Environmental Encyclopedia 3

Environmental health

gastrointestinal (GI) tract. The GI tract, along with the

urinary system are the main routes of excretion of dangerous

materials. Not surprisingly, those cells and tissues most inti-

mately and continuously in contact with dangerous materials

are among the ones most likely to be damaged. Ulcers,

infections, lesions, or tumors of the mouth, esophagus, stom-

ach, intestine, colon, kidney, bladder, and associated glands

are among the most common manifestations of environmen-

tal toxins. Other common routes of entry for toxins are

through the respiratory system and the skin. These also

are important routes for excreting or discharging unwanted

materials.

Some of our most convincing evidence about the toxic-

ity of particular chemicals on humans has come from experi-

ments in which volunteers (students, convicts, or others)

were deliberately given measured levels under controlled

conditions. Because it is now considered unethical to experi-

ment on living humans, we are forced to depend on proxy

experiments using computer models, tissue cultures, or labo-

ratory animals. These proxy tests are difficult to interpret.

We can’t be sure that experimental methods can be extrapo-

lated to how real living humans would react. The most

commonly used laboratory animals in toxicity tests are ro-

dents like rats and mice. However, different

species

can

react very differently to the same compound. Of some 200

chemicals shown to be carcinogenic in either rats or mice,

for instance, about half caused cancer in one species but not

the other. How should we interpret these results? Should

we assume that we are as sensitive as the most susceptible

animal, as resistant as the least sensitive, or somewhere in

between?

It is especially difficult to determine responses to very

low levels of particular chemicals, especially when they are

not highly toxic. The effects of random events, chance, and

unknown complicating factors become troublesome, often

resulting in a high level of uncertainty in predicting risk.

The case of the sweetener saccharin is a good example of

the complexities and uncertainties in

risk assessment

Studies in the 1970s suggested a link between saccharin and

bladder cancer in male rats. Critics pointed out that humans

would have to drink 800 cans of soft drink per day to get a

dose equivalent to that given to the rats. Furthermore, they

argued, most people are not merely large rats.

The

Food and Drug Administration

uses a range of

estimates of the probable toxicity of saccharine in humans.

At current rates of consumption, the lower estimate predicts

that only one person in the United states will get cancer every

1,000 years from saccharine. That is clearly inconsequential

considering the advantages of reduced weight, fewer cases

of diabetes, and other benefits from this sugar substitute.

The upper estimate, however, suggests that 3,640 people

492

will die each year from this same exposure. That is most

certainly a risk worth worrying about.

An emerging environmental health concern with a

similarly high level of uncertainty but potentially dire conse-

quences is the disruption of endocrine hormone functions by

synthetic chemicals. About ten years ago,

wildlife

biologists

began to report puzzling evidence of reproductive failures

and abnormal development in certain wild animal popula-

tions. Alligators in a lake in central Florida, for instance,

were reported to have a 90% decline in egg hatching and

juvenile survival along with feminization of adult males in-

cluding abnormally small penises and lack of sperm produc-

tion. Similar reproductive problems and developmental de-

fects were reported for trout in the

Great Lakes

, seagulls

in California, panthers in Florida, and a number of other

species. Even humans may be effected if reports of global

reduction of sperm counts and increases of hormone-depen-

dent cancers prove to be true.

Both laboratory and field studies point to a possible

role of synthetic chemicals in these problems. More than

50 chemicals, if present in high enough concentrations, are

now known to mimic or disrupt the signals conveyed by

naturally occurring endocrine hormones that control almost

every aspect of development, behavior, immune functions,

and

metabolism

. Among these chemicals are

dioxin

, poly-

chlorinated biphenyl, and several persistent pesticides. This

new field of research promises to be of great concern in the

next few years because it combines dread factors of great

emotional power such as undetectable exposure, threat to

future generations

, unknown or delayed consequences, and

involuntary or inequitable distribution of risk.

In spite of the seriousness of the concerns expressed

above, the

Environmental Protection Agency

warns that

we need to take a balanced view of environmental health.

The risks associated with allowable levels of certain organic

solvents in drinking water or some pesticides in food are

thought to carry a risk of less than one cancer in a million

people in a lifetime. Many people are outraged about being

exposed to this risk, yet they cheerfully accept risks thousands

of times as higher from activities they enjoy such as smoking,

driving a car, or eating an unhealthy diet. According to the

EPA, the most important things we as individuals can do

to improve our health are to reduce smoking, drive safely,

eat a balanced diet, exercise reasonably, lower stress in our

lives, avoid dangerous jobs, lower indoor pollutants, practice

safe sex, avoid sun exposure, and prevent household acci-

dents. Many of these factors over which we have control

are much more risky than the unknown, uncontrollable,

environmental hazards we fear so much.

[William P. Cunningham Ph.D.]

Environmental Encyclopedia 3

Environmental history

ESOURCES

OOKS

Foster, H. D. Health, Disease and the Environment. Boca Raton: CRC

Press, 1992.

Moeller, D. W. Environmental Health. Cambridge: Harvard University

Press, 1992.

Morgan, M. T. Environmental Health. Madison: Brown & Benchmark,

1993.

ERIODICALS

Hall, J. V., et al. “Valuing the Health Benefits of Clean Air.” Science 255

(February 14, 1991): 812–17.

Environmental history

Much of human history has been a struggle for food, shelter,

and survival in the face of nature’s harshness. Three major

events or turning points have been the use of fire, the devel-

opment of agriculture, and the invention of tools and ma-

chines. Each of these advances has brought benefits to hu-

mans but often at the cost of

environmental degradation

Agriculture, for instance, increased food supplies but also

caused

soil erosion

, population explosions, and support of

sedentary living and urban life. It was the Industrial Revolu-

tion that gave humankind the greater power to conquer and

devastate our

environment

. Jacob Bronowski called it an

energy revolution, with power as the prime goal. As he

noted, it is an ongoing revolution, with the fate of literally

billions of people hanging on the outcome.

The Industrial Revolution, with its initial dependence

on the steam engine, iron works, and heavy use of

coal

, made

possible our modern lifestyle with its high consumption of

energy and material resources. With it, however, has come

devastating levels of air, water, land, and chemical

pollution

In essence, environmental history is the story of the growing

recognition of our negative impact upon

nature

and the

corresponding public interest in correcting these abuses.

Cunningham and Saigo describe four stages of

conserva-

tion

history and environmental activism: 1) pragmatic re-

source conservation; 2) moral and aesthetic resource preser-

vation; 3) growing concern over the impact of pollution on

health and ecosystems; and 4) global environmental citi-

zenship.

Environmental history, like all history, is very much

a study of key individuals and events. Included here are

Thomas Robert Malthus, George Perkins Marsh,

Theodore

Roosevelt

, and Rachel Carson. Writing at the end of the

eighteenth century, Malthus was the first to develop a coher-

ent theory of population, arguing that growth in food supply

could not keep up with the much larger growth in popula-

tion. Of cruel necessity,

population growth

would inevita-

bly be limited by

famine

, pestilence, disease, or war. Modern

493

supporters are labeled “neoMalthusians” and include notable

spokespersons Paul Erlich and Lester Brown.

In his 1864 book Man in Nature, George Perkins

Marsh was the first to attack the American myth of super-

abundance and inexhaustible resources. Citing many exam-

ples from Mediterranean lands and the United States, he

described the devastating impact of land abuse through

de-

forestation

and soil erosion. Lewis Mumford called this

book “the fountainhead of the conservation movement,” and

Stewart Udall described it as the beginning of land wisdom

in this country. Marsh’s work led to forest preservation and

influenced President Theodore Roosevelt and his chief for-

ester,

Gifford Pinchot

Effective forest and

wildlife

protection began during

Theodore Roosevelt’s presidency whose term of office

(1901–1909) has been called “The Golden Age of Conserva-

tion.” His administration established the first wildlife refuges

and national forests.

At this time key differences emerged between propo-

nents of conservation and preservation. Pinchot’s policies

were utilitarian, emphasizing the wise use of resources. By

contrast, preservationists led by

John Muir

argued for leaving

nature untouched. A key battle was fought over the

Hetch

Hetchy Reservoir

Yosemite National Park

, a proposed

water supply for San Francisco, California. Although Muir

lost, the

Sierra Club

(founded in 1882) gained national

prominence. Similar battles are now being waged over

petro-

leum

extraction in Alaska’s

Arctic National Wildlife Ref-

uge

and mining permits on federal lands, including

wilder-

ness

areas.

Rachel Carson gained widespread fame through her

battle against the indiscriminate use of pesticides. Her 1962

book Silent Spring has been hailed as the “fountainhead of

the modern environmental movement.” It has been trans-

lated into over 20 languages and is still a best seller. She

argued against

pesticide

abuse and for the right of common

citizens to be safe from pesticides in their own homes.

Though vigorously opposed by the chemical industry, her

views were vindicated by her overpowering reliance on scien-

tific evidence, some given surreptitiously by government sci-

entists. In effect, Silent Spring was the opening salvo in the

battle of ecologists against chemists. Much of the current

mistrust of

chemicals

stems from her work.

Several historical events are relevant to environmental

history. The closing of the American frontier at the end of

the nineteenth century gave political strength to the Theo-

dore Roosevelt presidency. The 1908 White House Confer-

ence on Conservation, organized and chaired by Gifford

Pinchot, is perhaps the most prestigious and influential

meeting ever held in the United States.

During the 1930s, the

drought

in the American

Dust

Bowl

awakened the country to the soil erosion concerns first

Environmental Encyclopedia 3

Environmental history

voiced by Marsh. The establishment of the

Soil Conserva-

tion Service

in 1935 was a direct response to this national

tragedy.

In 1955, an international symposium entitled “Man’s

Role in Changing the Face of the Earth” was held at

Princeton University. An impressive assemblage of scholars

led by geographer Carl Ortwin Sauer, zoologist Marston O.

Bates, and urban planner Lewis Mumford documented the

history of human impact on the earth, the processes of

human alteration of the environment, and the prospects for

future habitability.

The Apollo moon voyages, especially Apollo 8 in De-

cember 1968 and the dramatic photos taken of Earth from

space, awakened the world to the concept of “spaceship

earth.” It was as though the entire human community gave

one collective gasp at the small size and fragile beauty of

this one planet we call home.

The two energy price shocks of the 1970s spawned by

the 1973 Arab-Israeli War and the 1979 Iranian Islamic

Revolution fundamentally altered American energy habits.

Our salvation came in part from our horrific waste. Simple

energy conservation

measures and more fuel-efficient au-

tomobiles, predominantly of foreign manufacture, produced

enough savings to cause a mid-1980s crash in petroleum

prices. Nonetheless, many efficiencies begun during the

1970s remain.

The Montreal Accord of 1988 is notable for being

the first international agreement to phase out a damaging

chemical,

chlorofluorocarbons

(CFCs). This was a direct

response to evidence from satellite data over

Antarctica

that

chlorine-based compounds were destroying the stratospheric

ozone

shield, which provides vital protection against dam-

aging

ultraviolet radiation

Key accidents and corresponding media coverage of

environmental concerns have powerfully influenced public

opinion. Common themes during the 1960s and 1970s in-

cluded the “death of Lake Erie,” the ravages of

strip mining

for coal, the confirmation of

automobile

exhaust as a key

source of

photochemical smog

, destruction of the ozone

layer, and the threat of global warming. The ten-hour An-

nenberg CPB project, Race to Save the Planet, is now com-

mon fare in

environmental science

telecourses.

Media coverage of specific accidents or sites has had

some of the greatest impact on public awareness of environ-

mental problems.

Oil spills

have provided especially vivid

and troubling images. The wreck of the

Torrey Canyon

1967 off southern England was the first involving a super-

tanker, and a harbinger of even larger disasters to come,

such as the

Exxon Valdez

spill in Alaska. The blowout of

an oil well in California’s Santa Barbara Channel played

nightly on network television news programs. Scenes of oil-

494

covered birds and muddy shorelines were powerful images

in the battle for environmental awareness and commitment.

The

Cuyahoga River

in Cleveland was so polluted

with petroleum waste that it actually caught fire twice.

Love

Canal

, a forgotten chemical waste dump in Niagara Falls,

New York, became the inspiration for passage of the Su-

perfund Act, a tax on chemical companies to pay for cleanup

of abandoned

hazardous waste

sites. It was also personal

vindication for

Lois Marie Gibbs

, leader of the Love Canal

Homeowners Association.

One

air pollution

episode in New York City was

blamed for the deaths of about 300 people. In response to

another in Birmingham, Alabama, a federal judge ordered

the temporary shutdown of local steel mills.

The loudest alarms raised against the growing use of

nuclear power

in the U.S. were sounded by the combina-

tion of the 1979 near-meltdown at

Three Mile Island Nu-

clear Reactor

in Pennsylvania and the subsequent (1986)

Chernobyl Nuclear Power Station

disaster in the Ukraine.

Media coverage and growing public awareness of pol-

lution problems, has led to widespread support for corrective

legislation. A large body of such legislation was passed be-

tween 1968 and 1980. Especially notable were the

National

Environmental Policy Act

, which created the

Environmen-

tal Protection Agency

, clean air and water acts, Superfund,

and the

Surface Mining Control and Reclamation Act

The latter required miners to reshape the land to near its

original contour and to replace

topsoil

, both essential keys

to the long-term recovery of the land.

Earlier noteworthy legislation includes the establish-

ment in 1872 of Yellowstone as the world’s first

national

park

; establishment of national wildlife refuges, forests, and

parks, and the agencies to oversee them; and the creation

of the

Soil Conservation

Service. The

Wilderness Act

1964 sought to set aside government land for nondestructive

uses only.

Much has been accomplished, and environmental is-

sues now command widespread public attention. A list of

books, journals, environmental organizations, and relevant

government agencies now fills six pages of small print in

one popular environmental textbook. Nonetheless, impor-

tant challenges lie ahead in the pursuit of a quality environ-

ment that will tax environmental organizations, government

policymakers, and voters.

Some key issues for the future can be grouped into

the following four categories. 1) Rapidly increasing costs

as control standards reach higher and higher levels. The

inexpensive and easy solutions have mostly been tried.

Solving the air pollution problems within the

Los Angeles

basin

is a prime example of this challenge. 2) Control

phosphates

and

nitrates

in our waterways will require

increasing commitment to tertiary (or chemical)

sewage

Environmental Encyclopedia 3

Environmental impact assessment

treatment

plants. We may also find it necessary to reroute

all

urban runoff

through such plants. 3) Solutions to the

global warming problem, if supported by ongoing scientific

research, will require alternative energy strategies, especially

as large, newly emerging economies of China, India, Brazil,

and other countries seek a growing share of the total

energy pie. 4) There is a growing conservative trend and

related hostility to environmental concerns among our

younger population. Consequently, the need for meaningful

environmental education

and dialogue will only continue

to increase.

[Nathan H. Meleen]

ESOURCES

OOKS

The American Experience. “Rachel Carson’s Silent Spring.” Boston: Public

Broadcasting System, 1993.

Cunningham, W. P., and B. W. Saigo. Environmental Science: A Global

Concern. 4th ed. Dubuque, IA: Wm. C. Brown, 1997.

Marsh, G. P. Man and Nature, or Physical Geography as Modified by Human

Action. 1864. Reprint, Cambridge, MA: Harvard University Press, 1965.

Miller Jr., G. T. Living in the Environment. 9th ed. Belmont, CA: Wadsw-

orth, 1996.

Thomas Jr., W. L., ed. Man’s Role in Changing the Face of the Earth.

Chicago: University of Chicago Press, 1956.

Environmental impact assessment

A written analysis or process that describes and details the

probable and possible effects of planned industrial or civil

project activities on the

ecosystem

, resources, and

environ-

ment

. The

National Environmental Policy Act

(NEPA)

first promulgated guidelines for environmental impact as-

sessments with the intention that the environment receive

proper emphasis among social, economic, and political prior-

ities in governmental decision-making. This act required

environmental impact assessments for major federal actions

affecting the environment. Many states now have similar

requirements for state and private activities. Such written

assessments are called Environmental Impact Statements

or EISs.

EISs range from brief statements to extremely detailed

multi-volume reports that require many years of data collec-

tion and analysis. In general, the environmental impact as-

sessment process requires consideration and evaluation of

the proposed project, its impacts, alternatives to the project,

and mitigating strategies designed to reduce the severity of

adverse effects. The assessments are completed by multi-

disciplinary teams in government agencies and consulting

firms. The experience of the United States

Army Corps of

Engineers

in detailing the impacts of projects such as

dams

and waterways is particularly noteworthy, as the Corps has

495

developed comprehensive methodologies to assess impacts

of such major and complex projects. These include evaluation

of direct environmental impacts as well as social and eco-

nomic ramifications.

The content of the assessments generally follows

guidelines in the National Environmental Policy Act. As-

sessments usually include the following sections:

Background information describing the affected population

and the environmental setting, including archaeological

and historical features, public utilities, cultural and social

values,

topography

hydrology

, geology and

soil

, clima-

tology,

natural resources

, and terrestrial and aquatic com-

munities;

Description of the proposed action detailing its purpose,

location, time frame, and relationship to other projects;

The environmental impacts of proposed action on natural

resources, ecological systems, population density, distribu-

tion and growth rate,

land use

, and human health. These

impacts should be described in detail and include primary

and secondary impacts, beneficial and adverse impacts,

short and long term effects, the rate of recovery, and impor-

tantly, measures to reduce or eliminate adverse effects;

Adverse impacts that cannot be avoided are described in

detail, including a description of their magnitude and im-

plications;

Alternatives to the project are described and evaluated.

These must include the “no action” alternative. A compara-

tive analysis of alternatives permits the assessment of envi-

ronmental benefits, risks, financial benefits and costs, and

overall effectiveness;

The reason for selecting the proposed action is justified as

a balance between risks, impacts, costs, and other factors

relevant to the project;

The relationship between short and long term uses and

maintenance is described, with the intent of detailing short

and long term gains and losses;

Reversible and irreversible impacts;

Public participation in the process is described;

Finally, the EIS includes a discussion of problems and

issues raised by interested parties, such as specific federal,

state, or local agencies, citizens, and activists.

The environmental impact assessment process pro-

vides a wealth of detailed technical information. It has been

effective in stopping, altering, or improving some projects.

However, serious questions have been raised about the ade-

quacy and fairness of the process. For example, assessments

may be too narrow or may not have sufficient depth. The

alternatives considered may reflect the judgment of decision-

makers who specify objectives, the study design, and the

alternatives considered. Difficult and important questions

exist regarding the balance of environmental, economic, and

Environmental Encyclopedia 3

Environmental Impact Statement

other interests. Finally, these issues often take place in a

politicized and highly-charged

atmosphere

that may not be

amenable to negotiation. Despite these and other limitations,

environmental impact assessments help to provide a system-

atic approach to sharing information that can improve public

decision-making. See also Risk assessment

[Stuart Batterman]

ESOURCES

OOKS

Rau, J., and D. G. Wooten, eds. Environmental Impact Analysis Handbook.

New York, McGraw-Hill, 1980.

THER

The National Environmental Policy Act of 1969, as Amended, P.L. 91-

140 (1 January 1970), amended P.L. 94-83 (9 August 1975).

Environmental Impact Statement

The

National Environmental Policy Act

(1969) made all

federal agencies responsible for analyzing any activity of

theirs “significantly affecting the quality of the human envi-

ronment.” Environmental Impact Statements (EIS) are the

assessments stipulated by this act, and these reports are

required for all large projects initiated, financed, or permitted

by the federal government. In addition to examining the

damage a particular project might have on the

environment

federal agencies are also expected to review ways of minimiz-

ing or alleviating these adverse effects a review which can

include consideration of the environmental benefits of aban-

doning the project altogether. The agency compiling an EIS

is required to hold public hearings; it is also required to

submit a draft to public review, and it is forbidden from

proceeding until it releases a final version of the statement.

The NEPA has been called “the first comprehensive

commitment of any modern state toward the responsible

custody of its environment,” and the EIS is considered one

of the most important mechanisms for its enforcement. It

is often difficult to identify environmental damages with

remedies that can be pursued in court, but the filing of an

EIS and the standards the document must meet are clear

and definite requirements for which federal agencies can be

held accountable. These requirements have allowed environ-

mental groups to focus legal challenges on the adequacy

of the report, contesting the way an EIS was prepared or

identifying environmental effects that were not taken into

account. The expense and the delays involved in defending

against these challenges have often given these groups pow-

erful leverage for convincing a company or an agency to

change or omit particular elements of a project. Many envi-

ronmental organizations have taken advantage of these op-

496

portunities; between 1974 and 1983, over 100 such suits

were filed every year.

Although litigation over impact statements can have

a decisive influence on a wide range of decisions in govern-

ment and business, the legal status of these reports and the

legal force of the NEPA itself are not as strong as many

environmentalists believe they should be. The act does not

require agencies to limit or prevent the potential environ-

mental damage identified in an EIS. The Supreme Court

upheld this interpretation in 1989, deciding that agencies

are “not constrained by NEPA from deciding that other

values outweigh the environmental costs.” The government,

in other words, is required only to identify and evaluate the

adverse impacts of proposed projects; it is not required, at

least by NEPA, to do anything about them. Environmental-

ists have long argued that environmental protection needs

a stronger legal grounding than this act provides; some such

as Lynton Caldwell, who was originally involved in the

drafting of the NEPA, maintain that only a constitutional

amendment will serve this purpose.

In addition to the controversies over what should be

included in these reports and what should be done about

the information, there have also been a number of debates

over who is required to file them. Environmental groups

have filed suit in the Pacific Northwest alleging that the

government should require

logging

companies to file impact

statements. And many people have observed that an EIS is

not actually required of all government agencies; the U. S.

Department of Agriculture, for instance, is not required to

file such reports on its commodity support programs.

Impact statements have been opposed by business and

industrial groups since they were first introduced. An EIS

can be extremely costly to compile, and the process of filing

and defending them can take years. Businesses can be left

in limbo over projects in which they have already invested

large amounts of money, and the uncertainties of the process

itself have often stopped development before it has begun.

In the debate about these statements, many advocates for

business interests have pointed out that environmental regu-

lation accounts for 23% of the 400 billion dollars the federal

government spends on regulation each year. They argue that

impact statements restrict the ability of the United States

to compete in international markets by forcing American

businesses to spend money on compliance that could be

invested in research or capital improvements. Many people

believe that impact statements seriously delay many aspects

of economic growth, and business leaders have questioned

the priorities of many environmental groups, who seem to

value

conservation

over social benefits such as high-levels

of employment.

In July of 1993, a judge in a federal district court

ruled that the

North American Free Trade Agreement