Environmental Encyclopedia

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Environmental Encyclopedia 3

Cholinesterase inhibitor

Zurer, P. S. “Producers Grapple with Realities of CFC Phaseout.” Chemi-

cal & Engineering News (24 July 1989): 7-13.

Cholera

Cholera is one of the most severe and contagious diseases

transmitted by water. It is marked by severe diarrhea, re-

sulting in fluid loss and dehydration, sometimes followed

by shock and death. If not treated,

mortality

occurs in over

60% of cases. The Latin American cholera epidemic claimed

4,002 lives in 1991, and resulted in 391,742 reported cases

that year, mostly in Peru and Ecuador. Cholera is caused

by the bacillus Vibrio cholerae, a member of the family Vib-

rionaceae, which are described as Gram negative, non-sporu-

lating rods that are slightly curved, motile, and have a fer-

mentative

metabolism

The natural

habitat

of V. cholerae is human feces, but

some studies have indicated that natural waters may also be

a habitat of the organism. Fecal contamination of water is

the most common means by which V. cholerae is spread,

however, food, insects, soiled clothing, or person-to-person

contact may also transmit sufficient numbers of the

patho-

gen

to cause cholera.

The ability of V. cholerae to survive in water is depen-

dent upon the temperature and water type. V. cholerae report-

edly survive longer at low temperatures, and in seawater,

sterilized water, and

nutrient

rich waters. Also, the particular

strain of V. cholerae affects the survival of the organism in

water, since some strains or types are hardier than others.

Most methods to isolate V. cholerae from water include con-

centration of the sample, by

filtration

, exposure to high

and selective media. Identification of pathogenic strains of

V. cholerae is dependent upon agglutination tests. Final con-

firmation of the strain or type must be done in a specialized

laboratory.

Persons infected with V. cholerae produce 10

to 10

organisms per milliliter in the stool at the height of the

disease, but the number of excreted organisms drops off

quickly as the disease progresses. Asymptomatic carriers of

V. cholerae excrete 10

to 10

organisms per gram of feces.

The mild form of the illness lasts for five to seven days.

Hydration therapy is the treatment of choice for cholera.

It is suggested that antibiotics not be used, following the

emergence of multiple antibiotic resistant strains in many

areas. Vaccines exist to prevent cholera, however, they do not

prevent the acquisition of the bacteria in the gastrointestinal

tract, do not diminish symptoms in persons already infected,

and are effective for well less than a year. Proper

water

treatment

should eliminate V. cholerae from drinking water,

247

however, the most effective control of this pathogen is de-

pendent upon good sanitary practices.

[E. K. Black and Gordon R. Finch]

ESOURCES

OOKS

Christie, A. B. Infectious Diseases: Epidemiology and Clinical Practice. 4th

ed. Edinburgh, Scotland: Churchill Livingstone, 1987.

Feachem, R. G., et al. Sanitation and Disease: Health Aspects of Excreta and

Wastewater Management. New York: Wiley, 1983.

Mitchell, R., ed. Environmental Microbiology. New York: Wiley-Liss, 1992.

ERIODICALS

Foliguet, J. M., P. Hartemann, and J. Vial. “Microbial Pathogens Transmit-

ted by Water.” Journal of Environmental Pathology, Toxicology, and Oncology

7 (1987): 39-114.

Cholinesterase inhibitor

Insecticides kill their target insect

species

in a variety of

ways. Two of the most commonly used classes of insecticide

are the organophosphates (nerve gases) and the carbamates.

These compounds act quickly (in a matter of hours), are

lethal at low doses (

parts per billion

), degrade rapidly (in

hours to days) and leave few toxic residues in the

environ-

ment

. Organophosphates kill insects by inducing loss of

control of the peripheral nervous system, leading to uncon-

trollable spasms followed by paralysis and, ultimately, death.

This is often accomplished by a biochemical process called

cholinesterase inhibition.

Most animals’ nervous systems are composed of indi-

vidual nerve cells called neurons. Between any two adjacent

neurons there is always a gap, called the synaptic cleft; the

neurons do not actually touch each other. When an animal

senses something—for example, pain—the sensation is

transmitted chemically from one neuron to another until the

impulse reaches the brain or central nervous system. The first

neuron (pre-synaptic neuron) releases a substance, known as

a transmitter, into the synaptic cleft. One of the most com-

mon chemical transmitters is called acetylcholine. Acetyl-

choline then diffuses across the gap and binds with receptor

sites on the second neuron (post-synaptic neuron). Reactions

within the target neuron triggered by occupied receptors

result in further transmission of the signal. As soon as the

impulse has been transmitted, the acetylcholine in the gap

is immediately destroyed by an

enzyme

called cholinester-

ase; the destruction of the acetylcholine is an absolutely

essential part of the nervous process. If the acetylcholine

is not destroyed, it continues to stimulate indefinitely the

transmission of impulses from one neuron to the next, lead-

ing to loss of all control over the peripheral nervous system.

When control is lost, the nervous system is first overstimu-

Environmental Encyclopedia 3

Chromatography

lated and then paralyzed until the animal dies. Thus,

or-

ganophosphate

insecticides bind to the cholinesterase en-

zyme, preventing the cholinesterase from destroying the

acetylcholine and inducing the death of the insect.

Some trade names for organophosphate insecticides

are malathion and parathion. Carbamates include aminocarb

and carbaryl. The carbamates produce the same effect of

cholinesterase inhibition as the organophosphates, but the

chemical reaction of the carbamates is more easily reversible.

The potency or power of these compounds is usually mea-

sured in terms of the quantity of the

pesticide

(or inhibitor)

that will produce a 50% loss of cholinesterase activity. Since

acetylcholine transmission of nervous impulses is common

to most vertebrates as well as insects, there is a great potential

for harm to non-target species from the use of cholinesterase-

inhibiting insecticides. Therefore the use of these insecticides

is highly regulated and controlled. Access to treated areas

and contact with the compounds is prohibited until the time

period necessary for the breakdown of the compounds to

non-toxic end products has elapsed.

[Usha Vedagiri]

ESOURCES

OOKS

Connell, D. W., and G. J. Miller. Chemistry and Ecotoxicology of Pollution.

New York: Wiley, 1984.

Chromatography

Chromatography is the process of separating mixtures of

chemicals

into individual components as a means of identi-

fication or purification. It derives from the Greek words

chroma, meaning color, and graphy, meaning writing. The

word was coined in 1906 by the Russian chemist Mikhail

Tsvett who used a column to separate plant pigments. Cur-

rently chromatography is applied to many types of separa-

tions far beyond those of just color separations. Common

chromatographic applications include gas-liquid chromatog-

raphy (GC), liquid-solid chromatography (LC), thin layer

chromatography (TLC),

ion exchange

chromatography,

and gel permeation chromatography (GPC). All of these

methods are invaluable in analytical

environmental chem-

istry

, particularly GC, LC, and GPC.

The basic principle of chromatography is that different

compounds have different retentions when passed through

a given medium. In a chromatographic system, one has a

mobile phase and a stationary phase. The mixture to be

separated is introduced in the mobile phase and passed

through the stationary phase. The compounds are selectively

248

retained by the stationary phase and move at different rates

which allows the compounds to be separated.

In gas chromatography, the mobile phase is a gas and

the stationary phase is a liquid fixed to a solid support.

Liquid samples are first vaporized in the injection port and

carried to the chromatographic column by an inert gas which

serves as the mobile phase. The column contains the liquid

stationary phase, and the compounds are separated based on

their different vapor pressures and their different affinities

for the stationary phase. Thus different types of separations

can be optimized by choosing different stationary phases,

and by altering the temperature of the column. As the com-

pounds elute from the end of the column, they are detected

by one of a number of methods that have specificity for

different chemical classes.

Liquid chromatography consists of a liquid mobile

phase and a solid stationary phase. There are two general

types of liquid chromatography: column chromatography

and high pressure liquid chromatography (HPLC). In col-

umn chromatography, the mixture is eluted through the

column containing stationary packing material by passing

successive volumes of solvents or solvent mixtures through

the column. Separations result as a function of both chemi-

cal-solvent interactions as well as chemical-stationary phase

interactions. Often this technique is used in a preparative

manner to remove interferences from environmental sample

extracts. HPLC refers to specific instruments designed to

perform liquid chromatography under very high pressures

to obtain a much greater degree of resolution. The column

outflow is passed through a detector and can be collected

for further processing if desired. Detection is typically by

ultraviolet light or fluorescence.

A variation of column chromatography is gel perme-

ation chromatography (GPC), which separates chemicals

based on size exclusion. The column is packed with porous

spheres, which allow certain size chemicals to penetrate the

spheres and excludes larger sizes. As the sample mixture

traverses the column, larger molecules move more quickly

and elute first while smaller molecules require longer elution

times. An example of this application in environmental anal-

yses is the removal of lipids (large molecules) from fish tissue

extracts being analyzed for pesticides (small molecules).

[Deborah L. Swackhammer]

ESOURCES

OOKS

McNair, H. M., and E. J. Bonelli. Basic Gas Chromatography. Palo Alto,

CA: Varian Instruments, 1969.

Peters, D. G., J. M. Hayes, and G. M. Hieftje. Chemical Separations and

Measurements. Philadelphia: Saunders, 1974.

Environmental Encyclopedia 3

Cigarette smoke

Chronic effects

Chronic effects occur over a long period of time. The length

of time termed “long” is dependent upon the life cycle of

the organism being tested. For some aquatic

species

chronic effect might be seen over the course of a month.

For animals such as rats and dogs, chronic would refer to a

period of several weeks to years.

Chronic effects can be either caused by chronic or

acute exposures. Acute exposure to some metals and many

carcinogens can result in chronic effects. With certain toxi-

cants, such as cyanide, it is difficult, if not impossible, to

cause a chronic effect. However, at a higher dosage, cyanide

readily causes

acute effects

. Examples of chronic effects

include pulmonary tuberculosis and, in many cases,

lead

poisoning

. In each disease the effects are long-term and

cause damage to tissues; acute effects generally result in little

tissue reaction. Thus, acute and chronic effects are frequently

unrelated, and yet it is often necessary to predict chronic

toxicity based on acute data. Acute data are more plentiful

and easier to obtain. To illustrate the possible differences

between acute and chronic effects, consider the examples of

halogenated solvents,

arsenic

, and lead.

In halogenated solvents, acute exposure can cause ex-

citability and dizziness, while chronic exposure will result

in liver damage. Chronic effects of arsenic poisoning are in

blood formation and liver and nerve damage. Acute poison-

ing affects the gastro-intestinal tract. Lead also effects blood

formation in chronic exposure, and damages the gastro-

intestinal tract in acute exposure. Other chronic effects of

exposure to lead include changes in the nervous system and

muscles. In some situations, given the proper combination

of dose level and frequency, those exposed will experience

both acute and chronic effects.

There are

chemicals

that are essential and beneficial

for the functions and structure of the body. The chronic

effect is therefore better health, although people generally

do not refer to chronic effects as being positive. However,

vitamin D, fluoride, and sodium chloride are just a few

examples of agents that are essential and/or beneficial when

administered at the proper dosage. Too much of any of the

three or too little, however, could cause acute and/or chronic

toxic effects.

aquatic toxicology

, chronic toxicity tests are used

to estimate the effect and no-effect concentrations of a chem-

ical that is continuously applied over the reproductive life

cycle of an organism; for example, the time needed for

growth, development, sexual maturity, and reproduction.

The range in chemical concentrations used in the chronic

tests is determined from acute tests. Criterion for effects

might include the number and percent of embryos that de-

249

velop and hatch, the survival and growth of larvae and juve-

niles, etc.

The maximum acceptable toxicant concentration

(MATC) is defined through chronic testing. The MATC

is a hypothetical concentration between the highest concen-

tration of chemical that caused no observed effect (NOEC)

and the lowest observed effect concentration (LOEC).

Therefore,

LOEC > MATC > NOEC

Furthermore, the MATC has been used to relate

chronic toxicity to acute toxicity through an application fac-

tor (AF). AF is defined as follows:

MATC

AF =

The AF for one aquatic species might then be used

to predict the chronic toxicity for another species, given the

acute toxicity data for that species.

The major limitations of chronic toxicity testing are

the availability of suitable test species and the length of time

needed for a test. In animal testing, mice, rats, rabbits, guinea

pigs, and/or dogs are generally used; mice and rats being

the most common. With respect to aquatic studies, the most

commonly used vertebrates are the fathead (fresh water) and

sheepshead (saltwater) minnows. The most commonly used

invertebrates are freshwater water fleas (Daphnia) and the

saltwater mysid shrimp (Mysidopsis). See also Aquatic chemis-

try; Detoxification; Dose response; Heavy metals and heavy

metal poisoning; LD

; Plant pathology; Toxic substance

[Gregory D. Boardman]

ESOURCES

OOKS

Manahan, S. E. Toxicological Chemistry. 2nd ed. Ann Arbor, MI: Lewis

Publishers, 1992.

Cigarette smoke

Cigarette

smoke

contains more than 4,000 identified com-

pounds. Many are known irritants and carcinogens. Since

the first Surgeon General’s Report on smoking and health

in 1964, evidence linking the use of

tobacco

to illness,

injury, and death has continued to mount. Many thousands

of studies have documented the adverse health consequences

of any type of tobacco, including cigarettes, cigars, and

smokeless tobacco.

Specific airborne contaminants from cigarette smoke

include respirable particles, nicotine,

polycyclic aromatic

hydrocarbons

arsenic

, DDT, formaldehyde,

hydrogen

Environmental Encyclopedia 3

Cigarette smoke

cyanide,

methane

carbon monoxide

, acrolein, and

nitro-

gen

dioxide. Each one of these compounds impacts some

part of the body. Irritating gases like ammonia, hydrogen

sulfide and formaldehyde affect the eyes, nose and throat.

Others, like nicotine, impact the central nervous system.

Carbon

monoxide reduces the oxygen-carrying capacity of

the blood, starving the body of energy. Carcinogenic agents

come into prolonged contact with vital organs and with the

delicate linings of the nose, mouth, throat, lungs and airways.

Cigarette smoke is one of the six major sources of

indoor

air pollution

, along with

combustion

by-products,

microorganisms

and allergens, formaldehyde and other or-

ganic compounds,

asbestos

fibers, and

radon

and its air-

borne decay products. The carbon monoxide concentration

in cigarette smoke is more than 600 times the level consid-

ered safe in industrial plants, and a smoker’s blood typically

has 4 to 15 times more carbon monoxide in it than that of

a nonsmoker. Airborne particle concentrations in a home

with several heavy smokers can exceed

ambient air

quality

standards.

Sidestream, or second-hand, smoke actually has higher

concentrations of some

toxins

than the mainstream smoke

the smoker inhales. Second-hand smoke carries more than

30 known carcinogens. According to a study by the

Centers

for Disease Control and Prevention

(CDC) released in

1996, nearly nine out of 10 nonsmoking Americans are

exposed to environmental tobacco smoke as measured by

the levels of cotinine in their blood. The presence of cotinine,

a chemical the body metabolizes from nicotine, is documen-

tation of exposure to cigarette smoke. On the basis of health

hazards of second-hand smoke, the

Environmental Protec-

tion Agency

has classified second-hand smoke as a Group

carcinogen

, known to cause

cancer

in humans.

Cigarettes probably represent the single greatest source

radiation exposure

to smokers in the United States

today. Two naturally occurring radioactive materials, lead-

210 and polonium-210, are present in tobacco. Both of

these long-lived decay products of radon are deposited and

retained on the large, sticky leaves of tobacco plants. When

the tobacco is made into cigarettes and the smoker lights

up, the radon decay products are volatilized and enter the

lungs. The resulting dose to small segments of the bronchial

epithelium of the lungs of about 50 million smokers in the

United States is about 160 mSv per year. (One Sv = 100

rem of radiation.) The dose to the whole body is about 13

mSv, more than 10 times the long-term dose rate limit for

members of the public.

The U. S. Department of Health and Human Services

reported in 1996 that more than 430,000 Americans die

each year from smoking. One in every five deaths in the

United States is smoking related, the largest preventable

cause of illness and premature death in the United States

250

About 10 million people in the United States have died

from causes attributed to smoking, including heart disease,

emphysema

, and other respiratory disease, since the first

Surgeon General’s report on smoking and health in 1964.

Death is caused primarily by heart disease, lung cancer,

heart disease, and chronic obstructive lung diseases such as

emphysema or chronic

bronchitis

. In addition, the use of

tobacco has been linked to cancers of the larynx, mouth and

esophagus, and as a contributory factor in the development

of cancers of the bladder, kidney, pancreas, and cervix. Ciga-

rette smoke aggravates

asthma

, triggers allergies, and causes

changes in bodily tissues that can leave smokers and non-

smokers prone to illness, especially heart disease.

About 180,000 Americans will die prematurely of cor-

onary heart disease every year due to smoking. The risk of

a stroke or heart attack is greatly increased by nicotine, which

impacts the platelets which enable the blood to clot. Nicotine

causes the surface of the platelets to become stickier, thereby

increasing the platelets’ ability to aggregate. Thus, a blood

clot or thrombus forms more easily. A thrombus in an artery

of the heart results in a heart attack; in an artery of the brain

it results in a stroke.

Epidemiological studies reveal a direct correlation be-

tween the extent of maternal smoking and various illnesses

in children. Also, studies show significantly lower heights

and weights in six to 11-year olds whose mothers smoke.

A pregnant woman who smokes faces increased risks of

miscarriage, premature birth, stillbirth, infants with low birth

weight, and infants with physical and mental impairments.

Cigarette smoking also impairs fertility in women and men,

contributes to earlier menopause, and increases a woman’s

risk of osteoporosis.

Cigarette smoke contains

benzene

which, when com-

bined with the radioactive toxins, can cause

leukemia

. Al-

though smoking does not cause the disease, smoking may

boost a person’s risk of getting leukemia by 30%.

A long-time smoker increases his risk of lung cancer

by 1,000 times. In 1986, according to the CDC, about

117,000 people died of lung cancer directly attributed to

cigarette smoke. More than 3,000 people each year develop

lung cancer from second-hand smoke. Between 1960 and

1990, deaths from lung cancer among women have increased

by more than 400%—exceeding breast cancer deaths.

The addiction to nicotine in cigarette smoke, a chemi-

cal and behavioral addiction as powerful as that of heroin,

is well documented. The immediate effect of smoking a

cigarette can range from tachycardia (an abnormally fast

heartbeat) to arrhythmia (an irregular heartbeat). Deep inha-

lations of smoke lower the pressure in a smoker’s chest and

pulmonary blood vessels, which increases the amount of

blood flow to the heart. This increased blood flow is experi-

enced as a relaxed feeling. Seconds later, nicotine enters the

Environmental Encyclopedia 3

Citizen science

liver and causes that organ to release sugar, which leads to

a “sugar high.” The pancreas then releases insulin to return

the blood sugar level to normal, but it makes the smoker

irritable and hungry, stimulating a desire to smoke and re-

cover the relaxed, high feeling.

Nicotine also stimulates the nervous system to release

adrenaline, which speeds up the heart and respiratory rates,

making the smoker feel more tense. Lighting the next ciga-

rette perpetuates the cycle. The greater the number of behav-

iors linked to the habit, the stronger the habit is and the

more difficult to break. Quitting involves combating the

physical need and the psychological need, and complete

physical withdrawal can take up to two weeks.

From an economic point of view, the Department of

Health and Human Services estimates that smoking costs

the United States $50 billion in health expenses. That figure

is most likely conservative because the medical costs attribut-

able to burn care from smoking-related fires, perinatal care

for low birth weight infants of mothers who smoke, and

treatment of disease caused by second-hand smoke were not

included in the calculation.

[Linda Rehkopf]

ESOURCES

OOKS

Haas, F., and S. Haas. The Chronic Bronchitis and Emphysema Handbook.

New York: Wiley, 1990.

Moeller, D. W. Environmental Health. Cambridge, MA: Harvard Univer-

sity Press, 1992.

ERIODICALS

Baker, S., and S. Carl. “Saving Your Lungs and Your Life.” Health (June

1991): 64.

CITES

see

Convention on International Trade in

Endangered Species of Wild Fauna and Flora

(1975)

Citizen science

Becoming a Citizen Scientist, according to the Cornell Uni-

versity Laboratory of Ornithology, can be as simple as glanc-

ing periodically at your backyard bird feeder, or as compli-

cated as getting out in the field, collecting data about the

relationship between an environments characteristics and the

success of bird-nesting in that milieu. Put simply, citizen

science is the practice of involving individual citizens,

through their voluntary efforts, in the work of

environmen-

tal science

. Such voluntary assistance encompasses a wide

variety of environmentally-related issues and projects, in-

251

cluding the counting of various

species

of bird, monitoring

rainfall amounts, or observing and surveying the habits of

threatened species of

wildlife

. The goal of all environmental

science, whether performed by private citizens or environ-

mental scientists, is the same: to provide for the health of

the planet, its

natural resources

, and all living beings.

John Fein, an internationally-renowned science educa-

tor, and associate professor at Griffith University (Brisbane,

Queensland,

Australia

), described this participatory process

as one that can “bridge the gap between science and the

community and between scientific research and policy, deci-

sion-making and planning.” “Bridging these gaps,” he went

on to note, “involves a process of social learning through

sound environmental research, full public participation, the

adoption of

adaptive management

practices and the de-

velopment of the democratic values, skills and institutions

for an active civil society.”

In the United States, citizen science began in the

1800s, and became more formalized in 1886, when the

Na-

tional Audubon Society

was created. According to its pre-

amble, the societys aim was to: promote the

conservation

of wildlife and the natural environment, and educate man

regarding his relationship with, and place within, the natural

environment as an ecological system. Public awareness of

environmental concerns increased with the first Earth Day

in 1970. The significance of

Earth Day

has served as a

reminder to the world community that it is not only the

scientists who are responsible for the health of the

environ-

ment

. The general public, each individual, has been given

the challenge to take measures large or small that might add

up to an enormous improvement in the ecological scheme

of life.

Today there are so many citizen science projects initi-

ated by various environmental organizations that it would

be impossible to list all of them. However, some of the better

known include:

The Christmas Bird Count, the oldest citizen science proj-

ect in existence, according to the National Audubon Soci-

ety. It occurs on a daily basis across the United States

between December 14th and January 5th each year. Until

the recent era of the home computer, it had been the

practice for groups to go on birding outings, “into nature”

in order to do the count.

The Great Backyard Bird Count, occurring for three days

commencing on Valentine Day involves volunteers count-

ing the birds visiting in their backyards or in nearby parks,

and entering the data into their computers. This count is

then analyzed and becomes available information to the

bird counters” through tables, maps, and in other forms.

The director of the Audubon Society in 2002, Frank Gill,

worked in coordinated effort with Dr. John W. Fitzpatrick,

Environmental Encyclopedia 3

Citizen science

director of the Cornell Lab of Ornithology, in order to

calculate the results.

Project Feeder Watch, a winter-long survey of birds that

visit feeders in backyards,

nature

centers, community areas,

and other locales that takes place November through

March.

The Birdhouse Network—involving the installation of bird

houses with volunteers monitoring bird activity throughout

the breeding season, collecting data on location,

habitat

characteristics, nestings and the number of eggs produced.

Project Pigeon Watch, counting the number of each differ-

ent color, recording the colors of courting birds, and help-

ing scientists determine the mystery of why there are so

many different colors of pigeons.

House Finch Disease Survey— the monitoring of backyard

feeders, reporting presence or absence of House Finch eye

disease.

Birds in Forested Landscapes— study sites established in

forests of varying sizes with volunteers counting the birds

during at least two visits (using recordings of vocalizations),

and searching for markers that breeding was successful,

recording landscape characteristics of the site;

Golden-winged Warbler Project— the study to survey and

conduct point counts at known and potential breeding sites

of this bird, using both professionals and volunteers;

Citizen Science in the Schoolyard— projects in elementary

and middle schools that educate children in various aspects

of bird-watching and counting;

BirdSource— an interactive online database operated in

conjunction with the Audubon Society collecting informa-

tion from numerous projects.

Adirondack Cooperative Loon Program, an ongoing proj-

ect with volunteers through the Natural History Museum

of the Adirondacks, with observation of the common loon

as well as the annual count that occurs every July.

The Mid-Atlantic Integrated Assessment (MAIA). A re-

search, monitoring, and assessment initiative under the

auspices of the

Environmental Protection Agency

, in or-

der to provide high-quality scientific information on the

condition of natural resources of the Mid-Atlantic region

of the east coast, including the Delaware and Chesapeake

Bays, Albemarle-Pamlico Sound, and the Delmarva

Coastal Bays, utilizing professional researchers and volun-

teers.

Smithsonian Neighborhood Nest-watch. Utilizing back-

yard bird counters during breeding season to assist the

Smithsonian Environmental Research Center in gathering

scientific data on various birds.

Citizen Collaborative for

Watershed

Sustainability. A

project conducted within the Southeast Minnesota Bluff-

lands region, and coordinating with other farming regions

252

across the state, in order to conserve the watersheds of

southeastern Minnesota.

Connecticut Department of Environmental Protection. A

citizen-based project to monitor streams and rivers, de-

termining the chemical, physical, and biological health of

the water.

Citizen science projects such as these have provided

information used in decision-making resulting in the pur-

chasing of lands that host certain threatened species during

breeding time and the development of bird population man-

agement guidelines. Further, data obtained from these sur-

veys is often published in scientific and educational journals.

Citizens respond

The

“explosion”

of popularity and participation in

citizen science has been a welcome development. Both the

United Nations and individual national governments have

become involved, sponsoring events such as the planned

2002 U.N. global summit scheduled for Johannesburg, South

Africa, between August 26th and September 4th, 2002 to

examine poverty, development, and the environment.

For citizens unaware of environmental issues, it ap-

pears that more information and publicity is necessary. In

an article for the Environmental News Network (ENN) in

October 2001, Erica Gies states, “As a person who cares

about environmental issues, I often find myself preaching

to the choir. But when I have an opportunity to converse with

people who are either uninformed or inclined to disagree, it

can be difficult to communicate my passion effectively with-

out alienating them, especially if they are people I have a

long history with, such as family.” To attain that goal of

increasing awareness, Gies suggests using art, literature and

the media. There are a variety of nonfiction books and essays,

poetry; art, and music featuring environmental or nature

themes, as well as the films focusing on environmental issues

featured each spring at an Environmental Film Festival held

in Washington, D.C. But even a comic strip can give an

ecological focus. Gies quotes Dilbert creator, Scott Adams

from his book, The Dilbert Future irreverently noting that,

“The children are our future. And that is why, ultimately, we’re

screwed unless we do something about it. If you haven’t noticed,

the children who are our future are good looking but they aren’t

all that bright. As dense as they might be, they will eventually

notice that adults have spent all the money, spread disease, and

turned the planet into a smoky, filthy ball of death.”

David Suzuki also offered his insights into the chal-

lenges facing the environment in an article for ENN in June

2002. Enumerating the biggest challenges for the environ-

ment in the next century, Suzuki noted, “I’m beginning to

think one of the biggest challenges is overcoming the fact

that people are tired of all the depressing news about the

environment.” Citizen science was offering a solution for

positive approaches and answers to these issues, giving the

Environmental Encyclopedia 3

Citizens for a Better Environment

public a reason to be hopeful and cherish their involvement

in seeing things change. One such person, Robert Boyle, of

Cold Spring, NY and author of the 1969 book, The Hudson

River: A Natural and Unnatural History continued his strug-

gle for 30 years after the publication of his book alerting

people to the decay of the

Hudson River

. His book was the

waterways equivalent of the Silent Spring (Rachel Carson’s

book that alerted the public to the danger of pesticides and

was responsible for much of the environmental movement

of the 1960s). Boyles book was instrumental in beginning

the process of cleaning up not only the Hudson River, but

all other polluted waterways across the United States. In

2002, Boyle continued to fight major industrial polluters

and the government in courts in his effort to preserve the

natural bounty of the Hudson River.

[Joan M. Schonbeck]

ESOURCES

THER

Adirondack Cooperative Loon Project. 2002 Annual Census. [cited June

2002]. <http://www.adkscience.org/>

Citizen Collaborative for Watershed Sustainability. About the Citizen Col-

laborative. [cited June 2002]. <http://www.sustain.org/>

Connecticut Department of Environmental Protection. A Volunteer opportu-

nity for citizens to monitor wadeable streams and rivers. 1998 [cited 2002].

<http://www.dep.state.ct.us/>

Cornell Lab of Ornithology. “Citizen Science.” What We Do. [cited June

2002]. <http://www.birds.cornell.edu/>

Environmental Protection Agency.Mid-Atlantic Integrated Assessment. May

15, 2002. <http://www.epa.gov/maia/>

Fein, John; Tim Smith; and, James Whelan. Cooperative Research Centre

for Coastal Zone, Estuary and Waterway Management. “Citizen Science and

Education—Theme 2.” January 3, 2002. <http://www.coastal.crc.org.au/>

Gies, Erica. Environmental News Network. “Responses to ’Fun literary

strategies for environmental debate’ An ENN perspective.” October 12,

2001. <http://www.enn.com/>

Gorman, James. “Naturalists share their findings online.” New York Times/

on the web. December 13, 2001.

Kansas State University. Citizen Science. “Links to help you participate in

scientific ornithological research.” [cited June 2002]. <http://

www.ksu.edu/>

Los Alamos. Citizen-Based Science: Collaboration between the U.S. Geological

Survey (USGS) and the Volunteer Task Force. [cited June 2002]. <http://

www.losalamos.com/mavtf/>

Smithsonian Environmental Research Center. Avian Ecology. “Neighbor-

hood Nestwatch.” [cited June 2002]. <http://www.serc.si.edu/>

Stoddard, Ed. Reuters. “Planet’s health source of much debate.” April 19,

2002. <http://www.enn.com/news/wire-stories/>

Suzuki, David. Environmental News Network. “Time to pull our heads out

of the sand.” June 13, 2002. <http://www.enn.com/>

University of Massachusetts. About the Ecological Cities Project. March 15,

2002. <http://www.umass.edu/ecologicalcities/>

Vermont Institute of Natural Science. Citizen Science. [cited June 2002].

<http://www.vinsweb.org/>

Virtanen, Michael. Associated Press. “At age 73, advocate refuses to quit

fight to keep the Hudson River free of pollution.” March 22, 2002. <http://

www.enn.com/news/wire-stories/>

253

RGANIZATIONS

Cornell Lab of Ornithology, P. O. Box 11, Ithaca, NY USA 14851 Toll

Free: (800) 843-2473, <http://www.birds.cornell.edu>

The Natural History Museum of the Adirondacks, P. O. Box 897, Tupper

Lake, NY USA 12986 (518) 359-2533, Fax: (518) 523-9841, <http://

www.adkscience.org>

Smithsonian Environmental Research Center, 647 Contees Wharf Road,

Edgewater, MD USA 21037 (443) 482-2200, Fax: (443) 482-2380,

<http://www.serc.si.edu>

Citizen’s Clearinghouse for Hazardous

Waste

see

Gibbs, Lois

Citizens for a Better Environment

Citizens for a Better Environment (CBE) is an organization

that works to reduce exposure to toxic substances in land,

water, and air. Founded in 1971, CBE has 30,000 members

and operates with a $1.8 million budget. The organization

also maintains regional offices in Minnesota and in Wis-

consin.

CBE staff and members focus on research, public in-

formation, and advocacy to reduce toxic substances. They

also meet with policy-makers on state, regional, and national

levels. A staff of scientists, researchers, and policy analysts

evaluate specific problems brought to the attention of CBE,

testify at legislative and regulatory agency hearings, and file

lawsuits in state and federal courts. The organization also

conducts public education programs, and provides technical

assistance to local residents and organizations that attempt

to halt toxic chemical exposures.

The Chicago office won a Supreme Court decision

against the construction of an incinerator in a low-income

neighborhood in the Chicago area and is researching the

issues on volume-based

garbage

for suburban Chicago

areas. In Minnesota, the staff has developed a “Good Neigh-

bor” program of agreements between community groups,

environmental activists, businesses, and industries along the

Mississippi River to reduce

pollution

of the river. In Wis-

consin,

transportation

issues under study include selling

ride-sharing credits to meet

Clean Air Act

standards. Selling

and buying of credits between and among individuals, busi-

nesses, and polluting industries has become a lucrative way

for polluters to continue their practices. CBE is attempting

to close the legislative loopholes that allows this practice to

continue.

The Chicago office maintains a library of books, re-

ports, and articles on environmental pollution issues. Publi-

cations include CBE’s Environmental Review, a quarterly

Environmental Encyclopedia 3

Clay minerals

journal on the public health effects of pollution; it includes

updates of CBE activities and research projects.

[Linda Rehkopf]

ESOURCES

RGANIZATIONS

Citizens for a Better Environment, 1845 N. Farwell Ave., Suite 220,

Milwaukee, WI USA 53202 (414) 271-7280, Fax: (866) 256-5988, Toll

Free: (414) 271-5904, Email: cbewi@cbemw.org, <http://

www.cbemw.org>

Clay minerals

Clay minerals contribute to the physical and chemical prop-

erties of most soils and sediments. At high concentrations

they cause soils to have a sticky consistency when wet. Indi-

vidual particles of clay minerals are very small with diameters

less than two micrometers. Because they are so finely divided,

clay minerals have a very high surface area per unit weight,

ranging form 5 to 800 square meters per gram. They are

much more reactive than coarser materials in soils and sedi-

ments such as

silt

and sand and clay minerals account for

much of the reactivity of soils and sediments with respect

adsorption

and

ion exchange

Mineralogists restrict the definition of clay minerals

to those aluminosilicates (minerals predominantly composed

aluminum

, silicon, and oxygen) which in

nature

have

particle sizes two micrometers or less in diameter. These

minerals have platy structures made up of sheets of silica,

composed of silicon and oxygen, and alumina, which is

usually composed of aluminum and oxygen, but often has

iron and magnesium replacing some or all of the aluminum.

Clay minerals can be classified by the stacking of these

sheets. The one to one clay minerals have alternating silica

and alumina sheets; these are the least reactive of the clay

minerals, and kaolinite is the most common example. The

two to one minerals have layers made up of an alumina sheet

sandwiched between two silica sheets. These layers have

structural defects that result in negative charges, and they

are stacked upon each other with interlayer cations between

the layers to neutralize the negative layer charges. Common

two to one clays are illite and smectite.

In smectites, often called montmorillonite, the inter-

layer ions can undergo cation exchange. Smectites have the

greatest

ion

exchange capacity of the clay minerals and are

the most plastic. In illite, the layer charge is higher than for

smectite, but the cation exchange capacity is lower because

most of the interlayer ions are potassium ions that are trapped

between the layers and are not exchangeable.

Some

iron minerals

also can be found in the clay-

sized fraction of soils and sediments. These minerals have

254

a low capacity for ion exchange but are very important in

some adsorption reactions. Gibbsite, an aluminum hydroxide

mineral, is also found in the clay-sized fraction of some soils

and sediments. This mineral has a reactivity similar to the

iron minerals.

[Paul R. Bloom]

Clay-hard pan

A compacted subsurface

soil

layer. Hard pans are frequently

found in soils that have undergone significant amounts of

weathering

. Clay will accumulate below the surface and

cause the

subsoil

to be dense, making it difficult for roots

and water to penetrate. Soils with clay pans are more suscep-

tible to water

erosion

. Clay pans can be broken by cultiva-

tion, but over time they will re-form.

Clayoquot Sound

Clayoquot (pronounced CLACK wit) Sound, located about

half way up the west coast of British Columbia’s Vancouver

Island, is a spectacular complex of interconnecting ocean

inlets, rocky islands, and narrow fjords cut into densely for-

ested mountains. Home to black bears, cougars,

wolves

bald eagles, marbled murrelets, five

species

salmon

, and

lush with ferns, mosses and other water-loving plants, the

area contains the largest remaining tract of

temperate rainf-

orest

on Vancouver Island. It also contains the southern-

most pristine, coastal rainforest valleys in North America.

The forest is dominated by Sitka Spruce, Western Hemlock,

Western Red Cedar, and Douglas Fir, many of which can

grow to 300 ft (100 m) high and 15 ft (5 m) in diameter,

and live over 1,500 years.

Temperate rainforests only occur in areas with a mild,

humid

climate

where a cold ocean is close to mountains.

They need at least 80 in (190 cm) of rain spread fairly evenly

throughout the year to keep the vegetation moist and lush.

These conditions occur only along the west coasts of North

America, Chile, New Zealand and Tasmania. Today, over

half of these magnificent forests are gone and the only re-

maining large tracts on earth are in southeastern Alaska,

coastal British Columbia, and Chile. This thin band of

coastal temperate

rain forest

contains some of the oldest

and largest trees on Earth and has more

biomass

(volume

of organic material) per unit area than any other

ecosystem

in the world.

Countless complex and unique ecological processes

take place in ancient forests, most of which scientists don’t

fully understand. A typical, old growth rain forest contains

trees of all ages, but many are between 250 and 1,000 years

Environmental Encyclopedia 3

Clayoquot Sound

old. A verdant collection of ferns, mosses, and

lichens

car-

pets the forest floor and forms thick blankets that smother

fallen tree trunks and drape the branches of standing trees.

Battered by centuries of wind and rain, the canopy of the

old growth forest is ragged and uneven with many broken

treetops and snags. A single ancient tree can provide life-

sustaining

habitat

for innumerable species of insects, birds,

and small mammals that burrow in its bark, nest in its

branches, den in hollow cavities in its trunk, and feed on

the garden of vegetation that festoons its branches. Many

of these animals never descend from the forest canopy and

have yet to be studied by scientists.

Dead trees also play important ecological roles in the

forest. Standing snags are home to many species of insects

and cavity-nesting birds. Fallen tree trunks, decaying slowly

on the humid forest floor, provide nutrients and habitat

to a flourishing community of

fungi

, insects, and other

woodland creatures. Tree seedlings germinate and thrive on

the spongy, nutrient-rich wood of fallen “nurse logs.” Over

90% of the trees in the temperate rainforest grew initially

on these nurse logs. Salmon connect the coastal forest to

the sea. Vast schools of salmon ascending the rivers to spawn

provide a key food for at least 22 animal species including

bears, eagles, and Orca

whales

. When they die, the salmon

fertilize streams, providing most of the nutrients that support

aquatic life that will feed young salmon until they return to

the ocean. Furthermore, salmon carcasses, dragged to the

shore by creatures that feed on them, provide up to half the

carbon

and

nitrogen

that nourishes streamside vegetation.

With about one quarter of the world’s remaining tem-

perate rain forest, British Columbia has been the site of

intense controversy over forest harvest policies and practices,

and Clayoquot Sound has been the focal point for much of

that debate. For more than 20 years, the area around Clayo-

quot was the site of confrontations and mass demonstrations

both for and against

logging

. In 1993, the area witnessed

the largest peaceful civil disobedience action in Canadian

history. Clayoquot became an international environmental

icon. Protests in support of activists there were held at Cana-

dian Embassies throughout the world, and a boycott of

Canadian timber products threatened the country’s biggest

industry.

Part of the basis for opposing further logging is the

scarcity

of coastal, temperate rain forest. More than 73%

of Vancouver Island has either already been logged or is

slated for future harvest. While about 13% of the Island’s

area is set aside in parks or preserves, less than 6% of the

original rain forest is protected. Of the 170 watersheds (val-

leys) on Vancouver Island greater than 10,000 acres (about

4,000 hectares) in size, only 12 remain undeveloped, and

half of those are in Clayoquot Sound.

255

Logging protests began in Clayoquot Sound in the

early 1980s, focusing first on Meares Island, where 90% of

the forest was designated for harvest. Environmentalists and

First Nations people work together to stop this logging. In

1984, the Tla-o-qui-aht and Ahousaht Bands declared the

island a Tribal Park, and loggers were turned away. This

was the first logging blockade in Canadian history, and it

attracted strong local and national support. The two largest

logging companies working in Clayoquot Sound at the time

were MacMillan Bloedel and the International Forest Prod-

ucts (Interfor). Together, in the 1980s, these two companies

were cutting nearly 1 million cubic meters (32,000 large

truck loads) per year from Clayoquot Sound forests.

In 1993, the British Columbia government announced

a new forestry and land-use decision that aimed to compro-

mise between environmental, economic, and social needs of

the area. It would reduce the size of clearcuts, and set aside

areas deemed exceptionally valuable or sensitive. A

Sierra

Club

mapping project revealed, however, that 74% of the

ancient temperate rain forests would be harvested under this

plan, and that many of the protected areas were bog and

marginal forest. Through the summer of 1993, mass protests

and road blockades occurred on a daily basis at Clayoquot

Sound. Altogether, more than 12,000 people traveled to this

remote location that summer to protest old growth forest

logging, and 856 were arrested for blockading roads into

logging areas. Rather than simply paying a fine and going

home, many of the protesters insisted on going to trial so

they could express their love for the forest and their dismay

that it was being cut down. A collection of statements made

in court was published in Clayoquot Mass Trials: Defending

the Rainforest.

As protests continued, tempers flared. Radicals on

both sides of the controversy engaged in hostile and destruc-

tive acts. Property damage included several logging bridges

burned, equipment vandalized, and tree spiking. On the

other side, angry loggers attacked and injured several pro-

testors. In August, more than 5,000 people from all over

British Columbia attended a demonstration in the nearby

town of Ucluelet to support logging. A poll conducted about

this time found that 52% of British Columbians support

the Clayoquot Compromise (in favor of continued logging)

while 39% opposed it. Fifty seven percent of the respondents

opposed the blockades, with 35% in favor and the remainder

undecided. About the same time, the Nuu-Chah-Nulth

Tribal Council announced that Native bands would not

support any land-use decision in Clayoquot Sound that ex-

cludes logging. It said such a decision would affect the area’s

economic viability and further alienate the land from poten-

tial Native use.

Probably the most powerful weapon in the environ-

mentalists arsenal was a worldwide consumer blockade of

Environmental Encyclopedia 3

Clean Air Act (1963, 1970, 1990)

Canadian wood products. A highly effective public relations

campaign mounted in Europe,

Australia

, and the United

States made logging of ancient forests at Clayoquot an inter-

national scandal. Several large firms including General Tele-

phone Company, Scott Paper, Walmart and Home Depot

announced that they would no longer buy or sell wood

or wood products harvested from old-growth forests in an

unsustainable manner. To counter the bad publicity, the

Provincial Government reduced the harvest at Clayoquot

from 959,000 cubic meters in 1988 to 0 in 1998.

In 1999 MacMillan Bloedel signed a Memorandum

of Understanding with the First Nations Tribal Council and

several national environmental groups. The memorandum

set up a joint venture called Iisaak Forest Resources, owned

51% by the the Nuu-chah-nulth Tribal Council, and 49%

by MacMillan Bloedel. Iisaak promised it would not log

areas larger than 2,470 acres (1,000 hectares) in any of Clayo-

quot’s untouched valleys, and would practice sustainable

practices focused on small scale logging,

non-timber forest

products

and eco-tourism rather than clearcutting of old-

growth trees. However, it said, during a transition period

of 50 years or so, some old-growth logging will continue

until second-growth timber grows big enough to harvest.

This joint venture presents a dilemma for many envi-

ronmentalists. On one hand, they want to respect indigenous

land rights, and often regard native people as having greater

environmental knowledge and sensitivity than those who

haven’t lived on the land for so long. On the other hand, if

the forestry practices of the native corporation turn out to

not really be sustainable, it may be difficult for environmen-

talists to criticize their former allies. The Friends of Clayo-

quot Sound, for example, refused to sign the Memorandum

of Understanding because they don’t support any further

cutting of old growth trees for any reason.

In 2000, Clayoquot Sound was designated a United

Nations Biosphere Reserve. However, this title doesn’t give

the rain forest any further protection. Perhaps more valuable

is the establishment of the Pacific Rim

National Park

along

the coast south of the town of Tofino. Nearly 125,000 acres

(50,000 hectares), much of it

old-growth forest

, is included

in this new national park. MacMillan Bloedel, once the

largest logging company in Canada, has been bought by the

U.S.-based Weyerhaeuser Corporation. Weyerhaeuser says

it intends to continue collaboration with Iisaak joint venture

and will honor the memorandum of understanding on man-

agement of Clayoquot Sound. Meanwhile, Interfor contin-

ues logging ancient forests, and environmentalists fear that

the cumulative effect of many small cuts will be the same

as if massive clearcuts had continued.

Much of the recent environmental activism in Clayo-

quot Sound has focused on salmon farming. Protestors claim

excess food and feces from caged fish pollutes water in the

256

Sound. Antibiotics and

chemicals

used to prevent diseases

in the densely packed fish pens can harm other sea life, and

escaped domesticated fish can be a threat to wild populations.

Furthermore, fish farm employees often kill marine mam-

mals and sea birds that approach open net-cage salmon pens.

It remains to be seen whether

sustainable forestry

can preserve the ancient forests or new regulations on fish

farming can protect

wildlife

and

water quality

. Even in

its less than pristine state, however, the Sound is a beautiful

place and offers great opportunities for a variety of types of

outdoor

recreation

[William P. Cunningham Ph.D.]

ESOURCES

OOKS

Berman, Tzeporah. Clayoquot & Dissent. Vancouver: Ronsdale Press, 1994.

Breen-Needham, Howard, et al, eds. Witness to Wilderness: the Clayoquot

Sound Anthology. Vancouver: Arsenal Pulp Press, 1994.

Krawczyk, Betty Shiver. Clayoquot: the Sound of My Heart. Custer, WA:

Orca Book Publishers, 1996.

MacIsaac, Ronald and Anne Champagne, eds. Clayoquot Mass Trials: De-

fending the Rainforest.. Gabriola Island, BC: New Society Publishers, 1994.

Mackenzie, Ian. Ancient Landscapes of British Columbia: a Photographic

Journey Through the Remaining Wilderness of British Columbia. Edmonton,

AB: Lone Pine Publishing, 1995.

McLaren, Jean. Spirits rising: the story of the Clayoquot Peace Camp, 1993.

Vancouver, BC: Pacific Edge Publishing, 2000.

Streetley, Joanna. Paddling Through Time: A Sea Kayaking Journey Through

Clayoquot Sound. Raincoast Books, 2000.

THER

Ross, Andrew. Chronology of Clayoquot Sound events. October 1996.

Department of Political Science, University of Victoria, BC. [cited July 9,

2002]. <http://sitka.dcf.uvic.ca/CLAYOQUOT/chronolo.htm#notes>.

Clean Air Act (1963, 1970, 1990)

The 1970 Clean Air Act and major amendments to the act

in 1977 and 1990 serve as the backbone of efforts to control

air pollution

in the United States. This law established one

of the most complex regulatory programs in the country.

Efforts to control air

pollution

in the United States date

back to 1881, when Chicago and Cincinnati passed laws to

control industrial

smoke

and soot. Other municipalities

followed suit and the momentum continued to build. In

1952, Oregon became the first state to adopt a significant

program to control air pollution, and three years later, the

federal government became involved for the first time, when

the

Air Pollution Control

Act was passed. This law provided

funds to assist the states in their air

pollution control

activ-

ities.

In 1963, the first Clean Air Act was passed. The act

provided permanent federal aid for research, support for the