EPA’s Draft Report on the Environment 2003

Message from the Administrator

I am pleased to present the U.S. Environmental Protection Agency’s 

Draft Report on the Environment, a key step toward building a set of

environmental indicators that will help answer the important questions

Americans have about the environment, and that will guide our environmental decision-making in the future. This draft report provides a frank

discussion of what we know—and what we don’t know—about the

condition of our nation’s environment. 

As we look over the past three decades, we see a real record of success in

cleaning up and protecting our nation’s environment. By many measures,

our environment is healthier today than it was in 1970. The nation’s

commitment to environmental protection has produced cleaner air, safer

drinking water for more Americans, and a much improved approach to

managing wastes. Where we once took our environment for granted, we

now intuitively understand the importance of environmental quality for

our future. Much work remains to be done, however, and we must

continue to build on our record of progress. 

With this draft report, we begin an important national dialogue on how we

can improve our ability to assess the nation’s environmental quality and human health, and how we use that knowledge to

better manage for measurable environmental results. I invite you to participate in this dialogue with us and our partners.

Your comments and feedback are essential to our future efforts.

The President has called for a government focused on priorities and dedicated to excellence in public service. His

Management Agenda is designed to improve the ability of the federal government to manage for results. 

I thank the many EPA staff members from every program and region, our federal, tribal, state and local government

partners, and the independent scientists and research institutions that contributed to this draft report. 

We are all stewards of this shared planet, responsible for protecting and preserving a precious heritage for our children

and grandchildren. As long as we work together and stay firmly focused on our goals, I am confident we will make our air

cleaner, our water purer, and our land better protected for future generations. 

Christine Todd Whitman

Administrator
EPA’s Draft Report on the Environment 2003

Executive Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i

Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii

Environmental Protection in Context . . . . . . . . . . . . . . . . . . . . . . x

Chapter 1 - Cleaner Air. . . . . . . . . . . . . . . . . . 1-1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Outdoor Air Quality. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3

Indoor Air Quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10

Global Issues. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11

Limitations of Air Indicators . . . . . . . . . . . . . . . . . . . . . . 1-13

Endnotes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14

Chapter 2 - Purer Water . . . . . . . . . . . . . . . . . 2-1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

Waters and Watersheds . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

Drinking Water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-12

Recreation in and on the Water . . . . . . . . . . . . . . . . . . . 2-15

Consumption of Fish and Shellfish . . . . . . . . . . . . . . . . . 2-17

Limitations of Water Indicators. . . . . . . . . . . . . . . . . . . . 2-21

Endnotes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-23

Chapter 3 - Better Protected Land. . . . . . . . . 3-1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

Land Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

Chemicals in the Landscape . . . . . . . . . . . . . . . . . . . . . . . 3-8

Waste and Contaminated Lands . . . . . . . . . . . . . . . . . . . 3-14

Limitations of Land Indicators . . . . . . . . . . . . . . . . . . . . 3-22

Endnotes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-23

Chapter 4 - Human Health . . . . . . . . . . . . . . .4-1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2

Health Status of the United States . . . . . . . . . . . . . . . . .4-3

Environmental Pollution and Disease . . . . . . . . . . . . . . .4-10

Measuring Exposure to Environmental Pollution . . . . . .4-17

Challenges in Developing Human Health Indicators . .4-20

Endnotes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-21

Chapter 5 - Ecological Condition . . . . . . . . . .5-1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-2

Landscape Condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-5

Biotic Condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-7

Chemical and Physical Characteristics . . . . . . . . . . . . . . .5-9

Ecological Processes . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-10

Hydrology and Geomorphology . . . . . . . . . . . . . . . . . . .5-12

Natural Disturbance Regimes . . . . . . . . . . . . . . . . . . . . .5-14

Ecological Condition as an Environmental Result . . . . .5-15

Challenges in Developing Ecological Condition 

Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-18

Endnotes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-20

Chapter 6 - Working Together for Environmental

Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-1

Appendix A - Summary of Questions and Indicators . . . . . . . . . .A-1

Appendix B - Types of Waste and Contaminated Lands . . . . . . .B-1

Appendix C - Acronyms and Abbreviations . . . . . . . . . . . . . . . . .C-1

Appendix D - Glossary of Terms . . . . . . . . . . . . . . . . . . . . . . . . . .D-1

Appendix E - Sources for Environmental Protection in Context . .E-1

Contents
i

EPA’s Draft Report on the Environment 2003

Executive Summary

Executive Summary

In this Report on the Environment, the U.S. Environmental

Protection Agency (EPA) presents its first-ever national

picture of the U.S. environment. The report describes

what EPA knows—and doesn't know—about the

current state of the environment at the national level,

and how the environment is changing. The report highlights the progress our nation has made in protecting its

air, water, and land resources, and describes the measures that can be used to track the status of the environment and human health. Key conclusions from this

report are summarized below. 

This report is the first step in EPA's Environmental

Indicators Initiative. Launched in November 2001, this

initiative seeks to develop better indicators that EPA can

use to measure and track the state of the environment

and support improved environmental decision-making.

As a first step in developing this report, EPA identified a

series of key questions about the environment—

questions such as: What is the condition of waters and

watersheds in the United States? What is the quality of

outdoor air in the United States? The Agency then

carefully examined data sources, including those from

other federal agencies, to identify indicators (e.g., the

extent of wetlands and the concentrations of criteria

pollutants in air) that could answer these questions on

a national level. 

These indicators provide the basis for this report. They

also reveal that there is much we don't know about the

status of our environment because we currently lack

sufficient information to provide a more complete picture. An important next step in EPA's initiative will be

working closely with other federal agencies, tribes,

states, local governments, non-governmental organizations, and the private sector to create a long-term

strategy for developing an integrated system of local,

regional, and national indicators. This work will involve a

number of challenges, including developing better data

to support better indicators, making indicators more

understandable and usable, and more fully elucidating

the linkage between the causes and effects of environmental pollution and stressors. 

EPA is issuing this report as a draft to stimulate dialogue

and invite input into developing and improving environmental indicators in the future. EPA welcomes your suggestions about how well this report communicates

environmental status and trends and how to better

measure and manage for environmental results. To learn

more about the Environmental Indicators Initiative, to

access the Technical Document that provides the

detailed scientific foundation for this report, or to provide comment and feedback on this report, please visit

http://www.epa.gov/indicators/.
T

he nation's air is much cleaner today than it was 30 years ago. Remarkably, this progress has occurred even while,

during the same 30-year period, the U.S. Gross Domestic Product increased 161 percent, energy consumption

increased 42 percent, and vehicle miles traveled increased 149 percent. Notwithstanding this progress, challenges

remain in attaining health based-standards for ozone and particulate matter, in improving visibility, and in understanding the nature and magnitude of issues posed by indoor air pollution.

ii

EPA’s Draft Report on the Environment 2003

Executive Summary

Cleaner Air

Outdoor Air

Emissions of the six principal air pollutants have

decreased. Over the last 30 years, total emissions of six

principal air pollutants have decreased by nearly 25 percent,

resulting in lower concentrations of these pollutants in ambient air. Many people live in areas of the country that do not

always meet the health-based standards for certain pollutants. More than 133 million people live in areas where monitored air quality in 2001 was unhealthy at times because of

high levels of at least one criteria air pollutant. At the same

time, the percentage of days across the country that air quality violated a health standard dropped from almost 10 percent in 1998 to 3 percent in 2001. 

Air toxics emissions have declined. The National Toxics

Inventory, which tracks 188 toxic pollutants, estimates that

nationwide air toxics emissions decreased almost 24 percent

from baseline levels (1990–1993) to 4.7 million tons annually in 1996. Although data and tools for assessing the impacts

of air toxics are limited, available evidence suggests that emissions of air toxics may still pose health and ecological risks in

certain areas of the U.S. 

One of the major components of acid rain, wet sulfate

deposition, has declined. Wet sulfate deposition levels for

1999–2001 showed reductions of 20 to 30 percent compared to levels for 1989–1991 over widespread areas in the

Midwest and the eastern U.S., where acid rain has had its

greatest impact. Wet nitrogen deposition decreased slightly

in some areas of the eastern U.S. but increased in others,

including those with significant agricultural activity.

Indoor Air

Indoor air quality remains a concern. Because the

American public spends most of its time indoors, indoor air

quality is a serious issue. While more information is needed

about pollutant exposures and their effects in indoor environments, national studies have shown that levels of some pollutants indoors can be much higher than outdoor levels. Two

indoor air pollutants of particular concern are radon and

environmental tobacco smoke (ETS), the latter especially for

children. We are achieving, however, decreases in exposure to

ETS. In 1998, young children were exposed to ETS in

approximately 20 percent of homes in the U.S.—down from

approximately 39 percent in 1986.

Global Issues

The stratospheric ozone layer has become thinner in

recent decades, principally over the Antarctic. While

acknowledging high uncertainties in the data, scientists calculate that since the 1980s, ultraviolet radiation levels at 10

stations in both the northern and southern hemispheres have

increased by 6 to 14 percent. However, it is believed that

because of the phase-out of ozone-depleting substances, the

stratospheric ozone layer will recover, and ultraviolet radiation

levels from human-induced stratospheric ozone depletion are

close to the maximum they will reach.
P

ristine waterways, safe drinking water, lakes for swimming and fishing, and aquatic life habitat are treasured

resources. The nation has made significant progress in protecting these resources in the last 30 years. For example, concerted action to protect the nation's waters has reduced discharges of pollutants to surface water and

improved safety of drinking water supplies. Challenges remain, however, including polluted runoff, landscape modification, changes to water flow, airborne pollutants settling into surface water, and the aging of both wastewater and

drinking water infrastructures. The precise scope and scale of these challenges—at the local and the national scale—

are uncertain.

iii

EPA’s Draft Report on the Environment 2003

Executive Summary

Purer Water

Waters and Watersheds

We know a great deal about the condition of the nation's

waters at the regional, state, tribal, and local levels, but

we do not have enough information to provide a comprehensive picture at the national level. The way in which the

nation collects water quality data does not support a comprehensive picture of watershed health at the national level.

The nation’s estuaries are in fair to poor condition, varying from poor conditions in the northeast, Gulf, and Great

Lakes regions to fair conditions in the West and Southeast,

based on measurements of seven coastal condition indicators. 

Rates of annual wetland losses have decreased from

almost 500,000 acres a year three decades ago to a loss of

less than 100,000 acres averaged annually since 1986.

Nevertheless, in key parts of the U.S., we continue to lose

valuable wetlands.

Drinking Water

An increasing number of people are served by community

water systems that meet all health-based drinking water

standards. In 2002, states reported that 94 percent of the

population served by community water systems were served

by systems that met all health-based standards, up from 79

percent in 1993. Underreporting and late reporting of data

affect the accuracy of this information. 

Recreation in and on the Water

The number of beach closings has increased, but this likely reflects more consistent monitoring, reporting, and use

of state-wide advisories over time, rather than a decline

in the condition of recreational waters. From 1997 to

2001, the percentage of beaches affected by advisories or

closings rose from 23 to 27 percent. During that same period, the number of agencies reporting to EPA on beach advisories and closings rose from 159 to 237. 

Consumption of Fish and Shellfish

The percentage of U.S. fresh waters under fish consumption advisories has increased in recent years. Similar to

beach closings, these increases may be the result of more

consistent monitoring and reporting, so they do not necessarily indicate that conditions are getting worse. An estimated

14 percent of river miles, 28 percent of lake acreage, and 100

percent of the Great Lakes and their connecting waters were

under fish consumption advisories for at least some portion

of 2001. Following the U.S. ban in the mid-1970s, PCB concentrations significantly declined in Lake Michigan fish and

concentrations of PCBs in lake trout declined consistently

through the year 2000 in Lakes Ontario, Huron, and

Michigan. 
T

he U.S. is a nation rich in land resources. Much like air and water, land is a resource that must be carefully protected. Protecting land resources means ensuring that lands meet current societal needs and support healthy communities and ecosystems. To this end, EPA's land protection activities focus on prevention, management, control, and

cleanup of various substances that are released to or used on land. Many other governmental and private agencies at

the federal, state, and local levels manage land for natural resource and conservation purposes.

iv

EPA’s Draft Report on the Environment 2003

Executive Summary

Land Use

The U.S. contains approximately 2.3 billion acres of land.

That total area includes 1,055 million acres of grasslands and

shrublands, 749 million acres of forests, 410 million acres of

agricultural lands, and 98 million acres of developed land.

The majority of land within the U.S. is privately owned.

Almost 1.5 billion acres of private and tribal land are managed solely by their owners, with zoning and other land use

regulations as the only constraints. The federal government

manages nearly 28 percent of the nation's land.

While land conservation efforts continue, the amount and

rate of land development has increased. More than 4 percent of the nation is designated as wilderness, and millions of

other acres are protected in parks, refuges, or other classifications of reserved land. In 1997, 4.3 percent of U.S. total land

area—98 million acres—was developed, up from 3.2 percent

in 1982. The pace of land development in the 1990s was 1.5

times that in the 1980s. 

Chemicals in the Landscape

Industrial releases of toxic chemicals as reported to the

Toxics Release Inventory have declined in recent years.

EPA's Toxics Release Inventory (TRI) tracks releases of more

than 650 chemicals. The original set of chemicals (332 of

the 650 TRI chemicals) from industries that have reported

consistently since 1988 shows that total on- and off-site

releases decreased 48 percent between 1988 and 2000, a

reduction of 1.55 billion pounds. In addition, between 1998

and 2000, toxic releases of all 650 TRI chemicals decreased

by approximately 409 million pounds. 

Testing of foods for pesticide residues in 2000 found

that no more than 1.4 percent of samples exceeded regulatory limits. Each year, the U.S. Department of Agriculture

works with states to collect and analyze samples of a variety

of foods for pesticide residues using methods that can detect

concentrations orders of magnitude lower than levels that

might cause health concerns.

Waste and Contaminated Lands

Over the last 40 years, the total amount of municipal

solid waste generated in the U.S. has increased, though

per capita generation has remained relatively constant

over the last decade. While the nation is generating more

waste, its waste management practices have improved, particularly through increased recycling. The amount of municipal

solid waste recovered (recycled or composted) increased

more than 1,100 percent in the last decade. 

The nation is making progress in dealing with hazardous

waste. In 1999, EPA estimated that the 20,000 businesses

within the U.S. classified as “large quantity generators”

(defined as those that generate more than 2,200 pounds of

hazardous waste each month) collectively generated 40 million tons of Resource Conservation and Recovery Act (RCRA)

hazardous waste. Between 1991 and 1998, for 17 of the most

toxic chemicals in hazardous waste, the total amount fell by

44 percent. Between 1998 and 2000, 12 billion pounds—

approximately one third—of all toxic chemicals used in industrial processes were recycled. Today, virtually all hazardous

waste is either recycled, or processed by treatment that

destroys the toxic pollutants or reduces the ability of the pollutants to enter the environment. Once treated, this waste is

disposed of in landfills designed to prevent any releases. This

represents a vast improvement over the disposal practices

used 25 years ago.

Better Protected Land
P

rotecting the health of the American public from environmental pollutants is a key part of EPA’s mission. People

need clean air, water, and land to live, breathe, eat, and drink. Over the past 100 years, our understanding of the

potential threats to our health from environmental pollution has grown, but there is still much to learn about environmental condition and human health.

v

EPA’s Draft Report on the Environment 2003

Executive Summary

The nation is making progress in cleaning up contaminated lands. As of October 2002, there were 1,498 sites on

the Superfund National Priorities List (NPL)—a list of the

most toxic waste sites in the nation. Of these, 846 sites are

construction completion sites (i.e., sites where physical construction of all cleanup actions are complete, immediate

threats are addressed, and all long-term threats are under

control). This is up from 149 construction completes in

1992. In addition, approximately 3,700 hazardous waste

management sites are subject to RCRA corrective action

which would provide for investigation and cleanup and remediation of releases of hazardous waste and constituents. Of

these, 1,714 high-priority sites are targeted for immediate

action by federal, state, and local agencies.

The health of the American public is generally good and

improving. People are living longer than ever before—in the

last century, life expectancy at birth increased from 51 to

79.4 years for women and from 48 to 73.9 years for men.

Infant mortality has dropped to the lowest level ever recorded

in the United States. Infant mortality is still higher in this

country than in other developed nations, however, and life

expectancy is somewhat lower. The death rate for the nation's

main health threats—heart disease, cancer, and stroke—is

decreasing, although the number of people developing some

diseases, such as childhood asthma, is increasing.

Many studies in people have demonstrated an association

between environmental exposure and certain diseases or

health problems. Examples include radon and lung cancer;

arsenic and cancer in several organs; lead and nervous system

disorders; disease-causing bacteria such as E. coli O157: H7

(e.g., in contaminated meat and water) and gastrointestinal

illness and death; and particulate matter and aggravation of

heart and respiratory diseases. 

There are still unanswered questions about the links

between some environmental pollution and health problems. Factors such as the amount and frequency of exposure

and a person's age, health, genetic make-up, and lifestyle

affect whether a person will show symptoms of exposure or

develop disease. Better disease data that could be linked

directly with environmental monitoring data would support

efforts to determine stronger connections between disease

and environmental exposure.

Some segments of the population, especially children and

the elderly, may be more susceptible to adverse health

effects from some environmental pollutants. People with

existing health problems and with compromised immune systems may also be at higher risk. Understanding the potential

impacts of pollutants on such sensitive groups is important in

shaping national health standards and policies.

Biomonitoring has helped document the reduction in

blood lead levels of young children in the past 25 years due

largely to the ban of leaded gasoline, as well as the reduction

of cotinine, a measure of the exposure to environmental

tobacco smoke, in children, partly due to declining numbers

of adult smokers. Using biomonitoring to measure pollutant

residues in the body is one way to identify the levels of pollutants that may cause health problems and can help gauge the

success of actions to limit exposure. Biomonitoring involves

taking samples (usually in blood or urine) from people to

measure individual exposure. 

Human Health
T

he nation's air, water, land, and living things interact in diverse and complex ways to shape the nation's ecological

condition. Currently, we lack the means of capturing all of the appropriate measures for the physical, chemical, and

biological factors that influence ecological condition on a national basis. Recognizing that ecological condition is best

described by considering the integration of all of the environment's parts and processes, we are beginning to get a

sense for how the conditions of our air, water, and land impact the health of our ecosystems.

vi

EPA’s Draft Report on the Environment 2003

Executive Summary

Ecological Condition

EPA is moving in the direction of using ecological condition to measure for results. For example, efforts to reduce

acid rain have had significant results: One-quarter to onethird of lakes and streams in three regions previously affected

by acid rain are no longer acidic. Measuring for ecological

results will require data about both ecological stressors (e.g.,

air and water pollutants) and ecological condition. It will also

require an understanding of the relationship between the two. 

The EPA Science Advisory Board's framework for assessing ecological condition provides a key organizational

tool for assessing ecological condition. This tool contains

six essential ecological attributes that characterize the health

and diversity of every ecosystem type. In this report, EPA has

examined various indicators that address these six attributes.

Assessments of condition that use many variables can be

summarized to make them more understandable and

usable. The index of biotic integrity (IBI), for example, is a

useful approach that combines multiple variables that reflect

the ecological condition of a place, such as biological diversity and the health of individual organisms. For example, a Fish

IBI, used to assess the condition of mid-Atlantic streams,

showed that 53 percent of these streams were in good or fair

condition and 31 percent were in poor condition (evaluation

of the remaining 16 percent was inconclusive). 

Currently, there are significant gaps in our ability to

describe ecological condition at the national level.

Ultimately, we want to have indicators that provide a national

picture and that can be used across the various ecosystem

types. Rare and at-risk species and population trends in bird

communities are promising indicators that may be used

across different ecosystems. 
vii

EPA’s Draft Report on the Environment 2003

Introduction

Working with Partners

Protecting the environment and human health is not EPA's task alone. Many federal departments implement legislation and manage

programs that contribute directly to those goals. State, local, and county governments, along with federally recognized tribes, administer environmental programs as well. Many other factors influence human and environmental health: individual choices, collective

actions by citizens, and decisions made by industry all contribute to the health of society as a whole, and of its surrounding environment. 

In developing this draft report, EPA learned much from the experiences of others: the White House Council on Environmental Quality,

other federal departments and agencies, tribes, and states; The H. John Heinz III Center for Science, Economics and the Environment;

NatureServe; the EPA Science Advisory Board; and the National Research Council. This draft report is much stronger as a result of

the comments, advice, and data they made available to EPA.

Introduction

How clean are our nation's air, water, and land? How

healthy are its people and ecosystems? How can we

measure the success of policies and programs to protect health and the environment?

This report provides the U.S. Environmental Protection

Agency's (EPA's) response to these questions, with the aim of

sparking a broader dialogue and discussion about how to

answer them in the future. The report has two key purposes:

■ To describe what EPA knows—and doesn't know—about

the current state of the environment at the national level,

and how the environment is changing.

■ To identify measures that can be used to track the status

of and trends in the environment and human health, and to

define the challenges to improving those measures.

This report is the first step in EPA's Environmental Indicators

Initiative. Launched in November 2001, this initiative seeks to

develop an improved set of environmental indicators that will

enable EPA to better manage for results and better communicate the status of the environment and human health. These

indicators will provide critical tools for EPA to define environmental management goals and measure progress toward

those goals. Early drafts of this report have already been

helpful in developing EPA's strategic plan for 2003 to 2008.

An important next step in EPA's initiative will include working

closely with partners—other federal agencies, states, tribes,

local government, non-governmental organizations, and the

private sector—to create a long-term strategy for developing

an integrated system of local, regional, and national indicators. This report is issued as a draft to stimulate dialogue and

invite input into developing and improving environmental

measures in the future. EPA welcomes your suggestions about

how well this report communicates environmental status and

trends and how to better measure and manage for results. To

learn more about the initiative and to provide your comments

and feedback, please visit http://www.epa.gov/indicators/.

Using Indicators to Measure Results

This report uses the lens of environmental and health indicators to bring the current state of the U.S. environment into

focus. Environmental indicators are measures that track environmental conditions over time. For example, they help measure the state of air, water, and land; the pressures on those

resources; the status of human health; and the integrity of

our nation's ecosystems. Examples of environmental indicators include concentrations of criteria air pollutants in ambient air, the extent of wetlands, and the levels of lead in the

blood of Americans.

Environmental and human health indicators focus on outcomes—actual environmental results, such as cleaner air and
viii

EPA’s Draft Report on the Environment 2003

Introduction

water or improved human health or ecosystem condition—

rather than on administrative actions, such as the number of

permits issued. At one time, administrative measures of performance were considered sufficient indicators of progress.

While administrative measures track what actions have been

taken, they don't tell us whether those actions actually

improved the environment or human health. Understanding

the effectiveness of environmental programs, and measuring

actual progress, requires indicators of health and environmental conditions. 

Exhibit i-1 depicts this “hierarchy” of measures. Levels 1 and

2 are indicators of “response”—government administrative

actions, such as the issuing of discharge permits, and

responses to those actions. Level 3 indicators measure pressures on the environment, such as changes in the quantities

of discharges to water. Levels 4, 5, and 6 all measure the

state of the resource—such as changes in ambient levels of a

pollutant or changes in the health of an ecosystem. To link

environmental protection with real-world results, indicators

and performance measures at each level of the hierarchy are

required.

This report focuses, where possible, on indicators that

describe environmental status and trends at a national level.

In many cases, however, national-level indicators do not yet

exist or are not supported by adequate data. In some of

these cases, local and regional indicators do exist and are featured as examples in this report; these indicators are valuable

for a number of reasons. They serve as examples of what

national indicators might look like in the future. They provide

important perspective on conditions at the local and regional

levels, they are critical to understanding cause-and-effect

relationships in the environment, and they provide an important tool for local decision-making.

Exhibit i-1: Hierarchy of Indicators

Source: Revised from EPA, Chesapeake Bay Program. Chesapeake Bay Hierarchy of Indicators. 2000. 

LEVEL 1 LEVEL 2LEVEL 3LEVEL 4LEVEL 5 LEVEL 6

Administrative Environmental

TOTAL PHOSPHORUS Wastewater Discharge Permit

O K

85 86 87 88 89 90 91 92 93 94 95 96 97 98

0.02

0.03

0.04

0.05

0.06

EPA, State/Tribal 

or Other 

Governments' 

Regulations/ 

Activities

Actions/ 

Responses by 

Regulated and 

Nonregulated 

Parties

Changes in 

Pressure or 

Stressor 

Quantities

Ambient 

Conditions

Exposure or 

Body 

Burden/Uptake

Ultimate Impacts: 

Changes in Human 

Health or 

Ecological 

Condition

Fish Index Macroinvertebrate Index

Fish and macroinvertebrate 

indices of biotic integrity 

(Mid-Atlantic Highlands)

26%

Poor

57%

17%

Good

21%

No fish

caught

14%

Poor

38%

27%

Good

Phosphorus Nitrogen

1985 2000 1985 2000

Total nutrient loads delivered 

to the Chesapeake Bay from 

MD, PA, VA, and DC, 1985 and 2000 

Phosphorus Goal Nitrogen Goal

Invitation to a Dialogue

EPA invites your participation in the discussion about this draft

report. We welcome your suggestions about this draft report,

the future directions for EPA’s Environmental Indicators

Initiative, how best to measure and manage for results, and how

to effectively communicate about environmental status and

trends to the public. To learn more about the initiative and to

provide your comments and feedback, please visit

http://www.epa.gov/indicators/.
ix

EPA’s Draft Report on the Environment 2003

Introduction

About This Report

This report is organized around five core chapters (see chart

below). The first three describe the current state of the primary components of the physical environment—air, water,

and land—and the principal stressors that can affect their

conditions. The final two chapters present indicators on

human health and ecological condition.

The report was driven by a series of questions, developed by

EPA, that address three themes: what is happening, why is it

happening, and what are the effects. For example, in the area

of outdoor air, the questions address the quality of the

nation's air (what is happening), the factors contributing to

outdoor air pollution (why), and the human health and ecological effects of outdoor air pollution (what are the effects). 

Once the questions were developed, EPA examined data

sources to identify potential indicators to address these

questions on a national level. Scientists from inside and outside EPA then screened these indicators for their scientific

soundness and relevance to the questions. Only indicators

judged to be scientifically sound were included in this report.

The questions posed in each chapter, and the indicators

selected to answer them, are listed in Appendix A. Chapter 6

describes some of the challenges in developing and using

indicators at the national level. The scientific foundation and

more detailed information for the indicators listed in this

report are presented in the accompanying Report on the

Environment Technical Document (available online at

http://www.epa.gov/indicators/).

This report provides significant information about the

nation's environment; however, its scope is limited in several

ways. First, the report focuses primarily on the U.S.; it does

not address international environmental conditions or issues

that may affect environmental quality in this country. Second,

the report provides information on status and condition, but

does not describe the many important initiatives that EPA

and its partners are undertaking to protect the environment

and human health. More information about specific program

initiatives and other indicator-related background materials, as

well as links to EPA partners, can be found online at

http://www.epa.gov/indicators/.

Chapter 1 - Cleaner Air Chapter 2 - Purer Water Chapter 3 - Better Protected Land Chapter 4 - Human Health Chapter 5 - Ecological Condition

Introduction

Chapter 6 - Working Together for Environmental Results

Outdoor Air Quality

Indoor Air Quality

Global Issues

Limitations of 

Air Indicators

Limitations of 

Water Indicators

Waters and Watersheds

Drinking Water

Recreation on and 

on the Water

Consumption of

Fish and Shellfish

Land Use

Chemicals in the 

Landscape

Limitations of 

Land Indicators

Waste and 

Contaminated Lands

Health Status of the 

United States

Environmental Pollution 

and Disease

Measuring Exposure to

Environmental Pollution

Challenges in Developing 

Human Health Indicators

Landscape Condition

Biotic Condition

Ecological Processes

Chemical and Physical

Characteristics

Hydrology and

Geomorphology

Natural Disturbance

Regimes

Ecological Condition as an 

Environmental Result

Challenges in Developing 

Ecological Condition

Indicators 
x

EPA’s Draft Report on the Environment 2003

In the mid 1990s, there were105.5 million acres of 

wetlands in the lower 48 states; based on estimates 

in the late 1980s, there were 170 million acres in 

Alaska, 52,000 acres in Hawaii.

66,645 miles of coastline

2000 Census recorded 281 

million people in the U.S.

The population increased by 38% 

between 1970 and 2000

Life expectancy for men 

and women increased 8% 

since 1970

More than half of 

the U.S. population 

lives within 50 

miles of the coast

PEOPLE

WATER 

RESOURCES

The Great Lakes are 60.2 million acres and 

contain 18% of the world's fresh water

Public 

supply

Total water 

withdrawals

402,000

Fresh water withdrawals - millions 

of gallons per day, 1995

40,200 8,890

134,000

190,000

Rural 

domestic 

livestock

Irrigation Thermoelectric 

power

Year 2000 population 

of the U.S.

26%

62%

12%

Children

under 18 years

Between 18 and

64 years

65 years and

older

Life expectancy for 

men born in 1999 is 

73.9 years and 79.4 

years for women 

born in 1999

3.7 million miles of 

rivers and streams in

the lower 48 states

Ground water 

provides 

approximately 50% 

of the nation's 

public water supply

Exhibit i-2 Environmental Protection in Context

EPA recognizes the importance of quality of life and sustainability in any effort to measure outcomes. The nation’s

environmental protection laws aim to improve Americans’ quality of life by simultaneously protecting health and

environmental resources and promoting economic prosperity. This exhibit provides some statistical context for

understanding environmental progress. See Appendix E for all source information.

Introduction
xi

EPA’s Draft Report on the Environment 2003

Introduction

Coastal waters support more 

than $54 billion in goods 

and services each year

*does not include Hawaii **includes cropland, pastureland, and Conservation 

Reserve Program land; does not include Alaska

749 million 

acres of forest

1,066 million 

acres of grasslands 

and shrublands*

98 million acres of 

developed land

530 million acres of agricultural land**

Area: 2.3 billion acres of U.S. land, 28% federally owned LAND 

USE

ENERGY 

AND 

ECONOMY

GDP 

increased 

160%, 

1970-2001

Energy consumption 

increased 43%, 

1970-2001

Change in energy 

used per unit of GDP, 

1970-2001

More than 4% of the nation is designated as wilderness and millions of other acres are protected 

in national parks, state parks, wildlife refuges, or other classifications of conserved land.

1970:

$3,578*

2001:

$9,215* 1970:

18.97**

2001:

10.39**

(*billions of chained

(1996) dollars)

(**thousand Btu per 

chained (1996) dollar)

Vehicle miles traveled increased 

149%, 1970-2001

Exhibit i-2 Environmental Protection in Context
xii

EPA’s Draft Report on the Environment 2003

Introduction
1-1

Chapter 1 -

Cleaner Air
standards. We have much to learn about the levels of toxic air

pollutants and the quality of air indoors. 

This chapter has three main sections: outdoor air quality,

indoor air quality, and global issues. Each section tries to

answer two general questions: What are the current conditions? What are the major contributors to change? Questions

about health and ecological effects are posed and explored

for a number of air quality issues. The chapter concludes

with a section on the limitations of the indicators to address

these questions.

Chapter 1 - Cleaner Air

1-2

EPA’s Draft Report on the Environment 2003

Introduction

How clean is the air we breathe outdoors? How does

pollution in the air affect the quality of land and

water? How healthful is the air in our homes and

offices? 

The air we breathe today is cleaner and more healthful than it

was 3 decades ago. Since 1970, total national emissions of

the six most common air pollutants have been reduced 25

percent. Remarkably, this improvement in national air quality

has occurred even while, during the same 30-year period, the

U.S. Gross Domestic Product increased 161 percent, energy

consumption increased 42 percent, and vehicle miles traveled

increased 149 percent (Exhibit 1-1).1

Building on this progress, work remains to ensure steady

improvements in air quality. For example, certain areas of the

country at times exceed national health-based air quality -50

0

50

100

150

200 Percent of Change from 1970

70 01

161%

149%

42%

39%

-25%

80909697989900 95

Energy Consumption

Aggregate Emissions

(Criteria Air Pollutants)

U.S. Population

Vehicle Miles

Traveled

Gross Domestic

Product

Exhibit 1-1: Comparison of growth measures and 

emission trends, 1970–2001

Source: EPA, Office of Air Quality Planning and Standards. Latest Findings on National 

Air Quality: 2001 Status and Trends. September 2002.

Introduction

Chapter 1: Cleaner Air

Outdoor Air Quality

Indoor Air Quality

Limitations of 

Air Indicators

Global Issues
1-3

Chapter 1 - Cleaner Air

EPA’s Draft Report on the Environment 2003

Outdoor Air Quality

I

n the 1970s, the U.S. Environmental Protection Agency

(EPA) identified six common—or “criteria”—air pollutants

for which it established National Ambient Air Quality

Standards (NAAQS) under the Clean Air Act: ground-level

ozone, particulate matter, carbon monoxide (CO), nitrogen

dioxide (NO2), sulfur dioxide (SO2), and lead.

At elevated ambient levels, these pollutants—both alone and

in combination—are associated with adverse effects on

human health and on the environment. Breathing those pollutants at harmful levels can result in respiratory problems, hospitalization for heart or lung disease, and even premature

death. They can also harm

aquatic life, vegetation, and

animals, as well as create

haze and reduce visibility. In

setting the national primary

standards for each of the

pollutants, EPA intended to

protect public health and

the environment, as required

by the Clean Air Act. By law,

the standards are to be periodically reviewed and revised

as appropriate. 

Information on air quality

trends for criteria air pollutants is based on actual

measurements of pollutant

concentrations in the ambient air at more than 5,000

monitoring sites across the

country. The data from

those readings support EPA’s

key indicators for measuring

outdoor air quality trends

and determine which areas

meet Clean Air Act standards.

What is the quality of the

outdoor air in the United

States?

Trends in criteria air pollutants, visibility, acid deposition, and

toxic air pollutants provide a picture of the nation’s air quality. The nation’s air quality is generally improving as measured

by declining concentrations of criteria air pollutants. Acid

deposition levels of sulfate are declining in the eastern U.S.,

the area most affected by deposition. Toxic air pollutants,

though not as widely measured as criteria pollutants, also

appear to be declining. Visibility in parks and other protected

areas remained relatively steady over the last decade, and

challenges remain in improving visibility. 

Criteria Air Pollutants

Average ambient concentrations of the six criteria polluOutdoor Air Quality

Indicators

Number and percentage of days that

metropolitan statistical areas have

Air Quality Index (AQI) values

greater than 100

Number of people living in areas with

ozone (8-hour) and particulate

matter (PM2.5) levels above the

NAAQS

Ambient concentrations of 

ozone, 8-hour

Ambient concentrations of

particulate matter (PM2.5)

Visibility

Deposition: wet nitrogen and 

wet sulfate 

Ambient concentrations of 

selected air toxics

Emissions of particulate matter,

sulfur dioxide, nitrogen oxides, and

volatile organic compounds

Lead emissions

Air toxics emissions

Emissions (utility): sulfur dioxide 

and nitrogen oxides

Outdoor Air Quality

Concentrations

versus

Emissions

Ambient—or surrounding—air concentration levels are the key measure of air quality and are based on the monitored amount (e.g., in

units of micrograms per cubic meter [μg/m3] or parts per million

[ppm]) of a pollutant in the air. Emissions levels are based on estimates and monitored measurements of the amount (e.g., in units of

tons) of a pollutant released to the air from various sources, such as

vehicles and factories. Some emissions travel far from their source to

be deposited on distant land and water; others dissipate over time and

distance. The health-based standards (National Ambient Air Quality

Standards) for criteria pollutants are based on concentration levels.

The pollutant concentration to which a person is exposed is just one of

the factors that determines if health effects occur—and their severity

if they do occur. 
Chapter 1 - Cleaner Air

1-4

EPA’s Draft Report on the Environment 2003

tants have shown improvements over the past 20 years.2 For

most parts of the country, the average ambient levels of lead,

CO, SO2, and NO2 are lower than the standards. But many

people live in areas of the country that do not always meet

the health-based standards for certain pollutants, especially

ozone and particulate matter. 

In fact, more than 133 million people lived in areas where

monitored air quality in 2001 was unhealthy at times because

of high levels of at least one criteria air pollutant (Exhibit

1-2).3 Based on EPA’s Air Quality Index (AQI) data the percentage of days across the country on which air quality

exceeded a health standard dropped from almost 10 percent

in 1988 to 3 percent in 2001 (Exhibit 1-3).4,5 Also, EPA has

conducted an analysis of 260 metropolitan statistical areas

(MSAs) for the 1990 to 1999 time period. This study shows

that in 212 MSAs the average ambient concentrations for at

least one of the criteria pollutants had downward trends, and

in 57 MSAs there were upward trends for at least one pollutant (with 34 of the 57 MSAs showing significant upward

Outdoor Air Quality

Air Quality Index

The Air Quality Index (AQI) is used for daily reporting of air quality as

related to ozone, PM, CO, SO2, and NO2. It describes the health

effects that may be associated with exposure to different levels of these

pollutants, the groups likely to be most sensitive to the pollutant, and

simple measures that can be taken to reduce exposure. 

AQI values range from 0 to 500. The higher the AQI value, the greater

the level of air pollution—and the greater the health danger. An AQI

value of 100 generally corresponds to the national air quality standard

for a pollutant. Thus, AQI values of less than 100 are usually considered satisfactory. When AQI values are higher than 100, air quality is

deemed unhealthy for certain sensitive groups of people; as values rise,

everyone becomes at risk. However, unusually sensitive people may experience health effects when AQI values are between 50 and 100.

The AQI scale is divided into six categories, each of which is identified

with a particular color that corresponds to a level of concern for

health. “Code orange,” for example, means that the air is “unhealthy

for sensitive groups,” and “code red” means that the air may be

unhealthy for everyone. The highest of the AQI values for the individual

pollutants becomes the AQI value for that day. For example, if one day

a certain area had AQI values of 150 for ozone and 120 for particulate matter, the AQI value would be 150 for the pollutant ozone on

that day. Appropriate sensitive groups are always cautioned about any

AQI value higher than 100.

In a recent “Roper Green Gauge Report,” based on a nationwide poll of

more than 2,000 people, 54 percent of those surveyed said they had

heard of “ozone days” or “code orange”/“code red” air quality days,

and 46 percent said they had reduced their exposure to air pollution by

modifying outdoor exercise or work habits.7

Exhibit 1-2: People living in areas with air quality 

concentrations at times above the level of the National 

Ambient Air Quality Standards (NAAQS) in 2001

0 50 100 150

Sulfur Dioxide

Particulate 

Matter (≤10μm)

Particulate 

Matter (≤2.5μm)

Carbon 

Monoxide

Lead

Any 

NAAQS

Ozone

Nitrogen 

Dioxide

Millions of People

Source: EPA, Office of Air Quality Planning and Standards. Latest Findings on National 

Air Quality: 2001 Status and Trends. September 2002. Pollutants

110.3 

(8-hour)

0.007

11.1

72.7

0.7

2.7

133.1

40.2 (1-hour)

0 Number of days with AQI > 100

3500

3000

2500

2000

1500

1000

500

198919911993

Year

1995199719992001 0 Percent of Total Days

24

20

16

12

8

4

0

Exhibit 1-3: Number and percentage of days with 

Air Quality Index (AQI) greater than 100, 1988–2001

Number of Days

Percent of Total Days

Note: Data are for MSAs > 500,000.

Source: Data used to create graphic are drawn from EPA, Office of Air Quality 

Planning and Standards. National Air Quality and Emissions Trends Report, 1997. 

Table A-15. December 1998; EPA, Office of Air Quality Planning and Standards. 

Air trends: Metropolitan area trends, Table A-17. 2001 (February 25, 2003; 

http://www.epa.gov/airtrends/metro.html).
1-5

Chapter 1 - Cleaner Air

EPA’s Draft Report on the Environment 2003

trends). Taken as a whole, the results of the study demonstrate significant improvements in urban air quality over the

past decade.6

Ozone is not emitted directly into the air but formed by the

reaction of volatile organic compounds (VOCs), nitrogen

oxides (NOX), and other chemical compounds in the presence of heat and sunlight, particularly in hot summer weather.

Chemicals such as those that contribute to formation of

ozone are collectively known as ozone “precursors.” Particulate matter is emitted directly, and is also formed when emissions of NOX, SO2, and other gases react in the atmosphere.

With decreases in emissions of VOCs and other ozone precursors, 8-hour ozone concentrations fell by 11 percent

nationally between 1982 and 2001.8 All regions experienced

improvement in 8-hour ozone levels during the last 20 years

except the North Central region, which showed little change

(Exhibit 1-4). However, in 2001 more than 110 million people

lived in counties with concentrations higher at times than the

8-hour standard for ozone.9 Southern California, the eastern

U.S., and many major metropolitan areas have continuing

ozone problems. 

In 2001, some 73 million people lived in counties where

monitored air quality at times exceeded the standard for fine

particulate matter (PM2.5)—those particles less than or equal

to 2.5 micrometers (μm).10 Concentrations of PM2.5 vary

regionally. California and much of the eastern U.S. have annual average PM2.5 concentrations higher than the level of the

Outdoor Air Quality

Exhibit 1-4: Trends in ozone levels, 1982–2001, averaged across EPA Regions

20%

8%

4%

2%

9%

0%

9%

9% 21%

24%

11%

1982 2001

.092 .082

1982 2001

.090 .082

1982 2001

.112 .090

1982 2001

.101 .093

1982 2001

.096 .092

1982 2001

.082 .080

1982 2001

.089 .081

1982 2001

.074 .074

1982 2001

.081 .074

1982 2001

.102 .078

1982 2001

.072 .057

The National Trend

Note: Alaska levels are included in EPA region 10 averages; Hawaii levels are included in EPA region 9 averages; and Puerto Rico levels are included in EPA region 

2 averages.

Source: EPA, Office of Air Quality Planning and Standards. Latest Findings on National Air Quality: 2001 Status and Trends. September 2002.

EPA Region 10

EPA Region 9

EPA Region 8

EPA Region 7

EPA Region 6

EPA Region 5

EPA Region 4

EPA Region 3

EPA Region 2

EPA Region 1

Based on annual 4th maximum 8-hour average Concentrations are in ppm
Chapter 1 - Cleaner Air

1-6

EPA’s Draft Report on the Environment 2003

annual PM2.5 standard (Exhibit 1-5). The number of people

living in counties with air quality levels that exceed the standards for ozone and PM signals continuing problems.

Visibility

Pollution is impairing visibility

in some of the nation’s parks

and other protected areas. In 1999, average visibility for the

worst days in the East was approximately 15 miles. In the

West, average visibility for the worst days was approximately

50 miles in 1999.11 Particulate matter is the major contributor to reduced visibility, which can obscure natural vistas.

Outdoor Air Quality

Without the effects of pollution, the natural visibility in the

U.S. is approximately 47 to 93 miles in the East and 124 to

186 miles in the West. The higher relative humidity levels in

the East result in lower natural visibility. 

Acid Deposition

Two of the key pollutants

that contribute to the formation of particulate matter—SO2 and NOX—react in the

atmosphere with water, oxygen, and oxidants to form acid

droplets. Rain, snow, fog, and other forms of precipitation

containing the mixture of sulfuric and nitric acids fall to the

Micrograms per Cubic Meter ( g/m

> 20

15 - 20

12 - 15

< 12

Do not meet minimum data completeness.

Minimum 11 samples per calendar quarter required.

Data unavailable.

PM2.5 Standard (annual arithmetic mean) is 15 g/m

Exhibit 1-5: 2001 annual average particulate matter (PM2.5) concentrations

Source: EPA, Office of Air Quality Planning and Standards. Latest Findings on National Air Quality: 2001 Status and Trends. September 2002.
1-7

Chapter 1 - Cleaner Air

EPA’s Draft Report on the Environment 2003

earth as acid rain (wet deposition). The particles also may be

deposited without precipitation, known as “dry deposition.”

Wet sulfate deposition has decreased substantially—20 to

30 percent—throughout the Midwest and Northeast, where

acid rain has had its greatest impact, between the periods

1989–1991 and 1999–2001 (Exhibit 1-6). During the same

period, wet nitrogen deposition decreased slightly in some

areas of the eastern U.S. but increased in other areas, including those with significant agricultural activity (Exhibit 1-7).12

Outdoor Air Quality

Toxic Air Pollutants

In addition to the six criteria

pollutants, the Clean Air Act

identifies 188 toxic air pollutants to be regulated. Among

those pollutants are benzene, found in gasoline; perchloroethylene, emitted from some dry cleaning facilities; and methylene chloride, used as a solvent by a number of industries.

Often referred to as “air toxics,” these are pollutants that may

cause cancer or other serious health effects—reproductive

effects or birth defects, for example—and may also cause

adverse ecological effects. 

Source: EPA, Office of Air and Radiation, Clean Air Markets Program. EPA Acid Rain Program: 2001 Progress Report. November 2002.

Exhibit 1-6: Wet sulfate deposition, 1989−1991 vs. 1999−2001

 Average of 1989-1991 Average of 1999-2001

(kg/ha)

>40

35

30

25

20

15

10

Wet SO Wet SO

(kg/ha)

>40

35

30

25

20

15

10

Source: EPA, Office of Air and Radiation, Clean Air Markets Program. EPA Acid Rain Program: 2001 Progress Report. November 2002. 

Exhibit 1-7: Wet nitrogen deposition, 1989−1991 vs. 1999−2001

(kg/ha)

>10

(kg/ha)

>10

Average of 1989-1991 Average of 1999-2001
Chapter 1 - Cleaner Air

1-8

EPA’s Draft Report on the Environment 2003

Because there is currently no national monitoring network for

toxics, concentrations of toxic air pollutants cannot be quantified on a comprehensive, national level. Data from several

metropolitan areas do show downward trends in selected

toxic air pollutants. For example, the levels of benzene measured at 95 urban monitoring sites decreased 47 percent from

1994 to 2000.13 Although data and tools for assessing the

impacts of air toxics are limited, available evidence suggests

that emissions of air toxics may still pose health and ecological risks in certain areas of the U.S.14

What contributes to outdoor

air pollution?

Both manmade and natural sources contribute to criteria and

toxic air pollutants. Emissions from factories, electric utilities,

oil refineries, waste incinerators, smelters, dry cleaners, agricultural facilities, construction equipment, woodstoves, slash

pile burning, cars, buses, planes, trucks, trains, and lawn mowers—among many other sources—contribute to outdoor air

pollution. Applying commercial products such as paints and

strippers can also produce air pollution through the release

of VOCs. Air pollution can also stem from natural processes

such as volcanoes, windblown dust, and wildfires. 

Most of the six criteria air pollutants show declining emissions since 1982 (Exhibit 1-1). But as reported in Latest

Findings on National Air Quality: 2001 Status and Trends, emissions of NOX, a contributor to ozone, particulate matter, and

acid rain formation, increased by 9 percent between 1982

and 2001, with a slight decrease (3 percent) between 1992

and 2001.15 A significant amount of that increase is attributed to growth in emissions from non-road engines, including

construction and recreation equipment and diesel vehicles.16

Data from the National Emissions Inventory (NEI) are used

for tracking trends in emissions over time. State and local

agencies, tribes, and industry provide input to the NEI database, which includes estimates of annual emissions, by source,

of air pollutants in each area of the country, on an annual

basis. EPA continuously reviews and improves estimates of

pollutant emissions. Emissions estimates for criteria pollutants

are currently under such evaluation and may be updated. 

Actual emissions of SO2 and NOX from electric utility plants,

which are significant sources of both pollutants, are monitored for a program designed to reduce acid rain. Sulfur dioxide emissions from sources affected by the Acid Rain Program

declined from nearly 16 million tons in 1990 to 10.6 million

tons in 2001.17 NOX emissions from utility sources decreased

from 6.7 million tons in 1990 to 4.7 million tons in 2001.18

The National Toxics Inventory, which uses data from the

Toxics Release Inventory and other sources, estimates that

nationwide air toxics emissions dropped approximately 24

percent between their baseline (1990 to 1993) and 1996 to

4.7 million tons annually.19

What human health effects are

associated with outdoor air

pollution? 

Outdoor air pollution can cause a wide variety of adverse

health problems. Some of the criteria pollutants, particularly

ozone, NO2, and SO2, are primarily associated with respiratory-related effects, including aggravation of asthma and other

respiratory diseases, irritation of the lungs, and respiratory

symptoms (e.g., cough, chest pain, difficulty breathing).

Short-term exposure to ozone has also been linked to lung

inflammation and an increased number of hospital admissions

and emergency room visits.20,21,22,23,24 Repeated short-term

exposures to ozone may damage children’s developing lungs

and may lead to reduced lung function later in life, whereas

long-term exposures to high ozone levels are a possible cause

of an increased incidence of asthma in children who engage in

outdoor sports.25 Carbon monoxide, on the other hand, primarily affects people with cardiovascular disease by reducing

oxygen in the blood, which aggravates angina.26

Particulate matter is associated with both respiratory-related

and cardiovascular effects, exhibiting a broader range of

effects. For example, short-term exposures to particulate matter may aggravate asthma and bronchitis and have been associated with heartbeat irregularities and heart attacks.27 Such

exposures have been linked to increased school absences and

lost workdays, hospital admissions, and emergency room visits, and even death from heart and lung diseases.28 Long-term

exposures have also been linked to deaths from heart and

lung disease, including lung cancer.29,30

People exposed to certain toxic air pollutants at sufficient

concentrations may also experience harmful health effects,

including cancer, respiratory and cardiovascular effects, damOutdoor Air Quality
1-9

Chapter 1 - Cleaner Air

EPA’s Draft Report on the Environment 2003

age to the immune system, and neurological, reproductive,

and developmental problems. Even at low doses, lead—both

a criteria and toxic air pollutant—is associated with damage

to the nervous systems of fetuses and young children, resulting in learning deficits and lowered IQ.31 Exposure to benzene, a widely monitored air toxic, has been linked to

increases in the risk of two types of cancer: leukemia and multiple myeloma.32 (For additional information on health effects

associated with outdoor air pollution, see Chapter 4 –

Human Health.)

What ecological effects are

associated with outdoor air

pollution?

Many health effects are associated with breathing polluted air,

but air also transports pollutants and deposits them onto

soils or surface waters, where they can potentially affect

plants, crops, property, and animals. Toxic substances in

plants and animals can move through the food chain and

pose potential risks to human health. Airborne mercury from

incineration, for example, can settle in water and contaminate

fish. People and other animals higher on the food chain (e.g.,

bald eagles, bears, and cougars)

that eat contaminated fish are

then exposed to potentially

harmful levels of mercury, which

is known to affect the nervous

system. (For additional information, see the section on

“Contaminated Fish and

Shellfish” in Chapter 2 – Purer

Water.)

Direct exposure to ozone under

certain conditions can be harmful to plants and forests; it

reduces overall plant health and

interferes with the ability of

plants to produce and store

food. Such weakened plants are

in turn more susceptible to

harsh weather, disease, and

pests. Through its effects on

plants, ozone can also pose

risks to ecological functions such as water movement, cycling

of mineral nutrients, and habitats for various animal and plant

species. Airborne particles also can have an adverse impact

on vegetation and ecosystems.33

Increased acid levels damage soils, lakes, and streams, rendering some waterbodies unfit for certain fish and wildlife

species. Indirect effects of acid deposition are also responsible for damage to forest ecosystems. Excess deposition of

acid ions in the soil causes calcium and other essential plant

nutrients to be leached from the soil, and thus no longer

available to sustain normal plant growth and maintenance.

The calcium depletion also causes a scarcity of worms and

other prey, affecting the ability of some birds to lay eggs and

bring them to term. 

Acid ions also can increase the movement of aluminum in soil,

which competes with calcium and other nutrients in plant

roots during absorption, further limiting plant growth. Acid

deposition can also produce elevated levels of aluminum in

waterbodies. This results either from direct deposits acidifying the waterbody itself or from water passing through soil

that is high in aluminum and then entering the waterbody

from adjacent terrestrial systems. Those elevated levels of aluminum in water can be toxic to fish and other aquatic life.34

The nitrogen in acid rain is one of

the sources contributing to the total

amount of nitrogen in terrestrial and

aquatic systems. Although nitrogen

is a necessary nutrient in productive

ecosystems, too much nitrogen in

terrestrial systems can cause

changes in biodiversity. In aquatic

systems, it fuels excessive growth of

algae in coastal waters. When the

dense algal blooms die, bacteria

decay them. That process uses up

the oxygen that is needed by fish to

survive. (For additional information

on the effects of nitrogen on waterbodies, see the section on “Waters

and Watersheds” in Chapter 2 –

Purer Water.)

Outdoor Air Quality
Chapter 1 - Cleaner Air

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Indoor Air Quality

Air pollution is also an issue indoors. There are many

potential sources of indoor pollution, such as tobacco

smoke, building materials, cleaning fluids, pesticides,

and outdoor air pollution that seeps inside. But few studies

have examined the overall presence of indoor pollutants or

the extent of human exposure to them. Scientists know that

indoor air pollutants can cause long- and short-term health

effects, but experts face challenges in determining the consequences of exposure to various indoor air pollutants at low

levels for long periods of time. 

What is the quality of the air in

buildings in the United States?

There is no comprehensive monitoring of the quality of

indoor air in the U.S., and the actual levels for many pollutants are not well understood. Nonetheless, studies have

demonstrated that indoor levels of some pollutants can be

much higher than outdoor levels. Because most people spend

the majority of their time indoors, the indoor air quality of

the nation’s homes, work places, and schools is a serious

issue.

Two indoor air pollutants of

particular concern are environmental tobacco smoke

(ETS) and radon. A 1998

survey estimated that young

children were exposed to

ETS in approximately 20

percent of homes in the

U.S.—down from approximately 39 percent in

1986.35 Based on a representative 1991 survey of all

homes in the U.S., an estimated 6 million homes had high

radon levels—levels equal to or greater than EPA’s action level

of 4 picocuries per liter.36 Those homes represented about 6

percent of housing units in the U.S. 

What contributes to indoor air

pollution?

Indoor air pollutants include naturally occurring radon, ETS,

particulate matter, asbestos, molds, dust mites, lead and other

toxic air pollutants, VOCs, pesticides, and gases emitted from

Indoor Air Quality

Indicators

U.S. homes above EPA’s radon 

action levels

Percentage of homes where young

children are exposed to environmental

tobacco smoke

Indoor Air Quality

Indoor Air Quality in Office Buildings

The goal of the EPA’s Building Assessment Survey and Evaluation (BASE) Study was to define the status of U.S. office buildings with respect to indoor

air quality and occupants’ perceptions of that quality. In this study, conducted between 1994 and 1998, a sample of 100 office buildings was used to

characterize the central tendency—mean or median levels—of indoor air quality in commercial or public office buildings, representing the size building

in which 73 percent of all office employees work. In a subset of the first 56 of those buildings, EPA measured the indoor concentrations of 48 VOCs. In

a preliminary analysis, 34 VOCs were detected in 81 percent or more of the samples. All measurable VOCs were present at higher levels indoors than

outdoors, suggesting the presence of indoor sources.37 In most buildings, the indoor concentration of particulate matter was lower than or nearly equal

to the measured outdoor level. However, 11 of the buildings had PM10 (particles less than or equal to 10 μm) levels at least 50 percent higher than

outdoor levels, which could be a significant factor in a person’s total exposure.38
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inadequately vented heaters and pilot lights. Sources also

include certain furnishings and improperly stored solvents,

cleaners, pesticides, paints, and other household chemicals.

Concentrations of certain

chemical compounds and radon

can become particularly problematic when homes or buildings are tightly sealed and have

little exchange of indoor and

outdoor air. Like many other air

pollutants, concentrations of

indoor radon vary widely from

one location to another, and

around the country as well.

What human health effects are

associated with indoor air

pollution?

Poor indoor air quality can cause short-term problems, including headaches, fatigue, dizziness, nausea, and a scratchy

throat. But its other effects include cancer—particularly from

long-term exposures to high ETS and radon concentrations—

and aggravation of chronic respiratory diseases such as asthma. Exposure to naturally occurring radon gas is the second

leading cause (after smoking tobacco) of lung cancer among

Americans.39 The most sensitive and vulnerable population

groups—older people, the young, and the chronically ill—

tend to spend the most time indoors and may therefore face

higher-than-usual exposures.

Global Issues

Global Issues 

Ozone depletion has global consequences for human

health and the environment. Ozone depletion takes

place when pollution damages the thin layer of beneficial ozone in the stratosphere, about 6 to 30 miles above

the Earth, which protects living beings from harmful ultraviolet

(UV) radiation from the sun. 

The issue of global climate change involves changes in the

radiative balance of the Earth—the balance between energy

received from the sun and emitted from Earth. This report

does not attempt to address the complexities of this issue.

For information on the $1.7 billion annual U.S. Global

Climate Research Program and Climate Change Research

Initiative, please find Our Changing Planet: The Fiscal Year

2003 U.S. Global Climate Research Program (November 2002)

at http://www.usgcrp.gov and the Draft Ten–Year Strategic

Plan for the Climate Change Science Program at http://www.

climatescience.gov.

Ozone depletion in the

stratosphere and climate

change are separate environmental issues but are related

in some ways. Specifically,

some substances that

deplete the stratospheric

Global Issues

Indicators

Ozone levels over North America

Worldwide and U.S. production 

of ozone-depleting substances
ozone layer also are potent and very long-lived greenhouse

gases that absorb outgoing radiation and warm the atmosphere. Ozone itself is a greenhouse gas when it absorbs

incoming solar radiation and its depletion in the stratosphere

over the polar zones results in localized cooling at times. 

What is happening to the

Earth’s ozone layer?

In recent decades, the Earth’s stratospheric ozone layer has

become substantially thinner. The thinning has occurred principally over Antarctica and is referred to as the “ozone hole.”

The ozone layer over the Northern Hemisphere’s middle latitudes is about 2 percent below normal

during summer and autumn

and about 4 percent below

normal in winter and

spring.40 Between

1979 and 1994, the

ozone layer thinned

8 percent over

Seattle, 10 percent

over Los Angeles, and

2 percent over

Miami.41 

Scientists generally agree that a

thinning of the stratospheric ozone layer causes an increase

in the amount of ultraviolet (UV) radiation. While acknowledging high uncertainty in the data, scientists have calculated

that UV radiation levels at more than 10 sites in both hemispheres have increased by 6 to 14 percent since the 1980s.42

EPA, in partnership with the National Weather Service, publishes an index that predicts UV intensity levels for different

cities on a scale of 0 to 10+, where 0 indicates a minimal risk

of overexposure and 10+ means a very high risk. 

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EPA’s Draft Report on the Environment 2003

Global Issues

What is causing changes to the

ozone layer?

Stratospheric ozone depletion is associated with the use of

chlorofluorocarbons (CFCs), halons used to extinguish fires,

and other chemicals used as solvents. Air conditioners, refrigerators, insulating foams, and some industrial processes all

emit those substances. Air currents carry molecules with chlorine and bromine from those pollutants into the stratosphere,

where they react to destroy ozone molecules. 

The U.S. virtually ceased production of most ozone-depleting

substances in January 1996, because of its participation in an

international agreement, the Montreal Protocol on Substances

that Deplete the Ozone Layer. Nonetheless, ozone-depleting

substances are still being released into the environment, as

reported in the Toxics Release Inventory. Along with other

developed countries, the U.S. makes substitutes for the

strong ozone-depleting CFCs. These substitutes are themselves less ozone-depleting than the substances they replace.

Also, because the Montreal Protocol controls production but

not use, emissions continue from materials made before

January 1996. Even though scientists believe that recovery is

under way, full restoration of the stratospheric ozone layer will

take decades because of the continued use of products manufactured before the ban.

What are the human health and

ecological effects of stratospheric ozone depletion?

Thinning of the stratospheric ozone layer allows more of the

sun’s UV radiation to reach Earth, where it contributes to

increased incidences of human skin cancers, the most common of all cancers. Cataracts and suppression of the human

immune system may also result from increased exposure to

UV radiation. In addition, productivity of some marine phytoplankton, essential to the ocean’s food chain, may be unduly

stressed by high levels of UV radiation.43
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Many sources of data support indicators that help to

answer questions about the trends in outdoor and

indoor air quality and stratospheric ozone. But

there are limitations in using the indicators to fully answer the

questions.

Outdoor Air

In general, there are some very

good measures of outdoor air

quality. Although the national air monitoring network for the six

criteria air pollutants is extensive, there are far more monitors in

urban areas than in rural areas. That helps to characterize population exposures, because population tends to be concentrated

in developed areas, but it may make it more difficult to assess

effects associated with the transport of air pollutants and ecological effects. Recently, EPA and states have begun evaluating

and planning a nationwide monitoring network for air toxics.

With a few notable exceptions such as power plants, emissions

quantities for both the criteria pollutants and air toxics are

based on engineering estimates derived from more limited actual

data. There is a need for measures to compare actual and predicted human health and ecological effects related to exposure

to air pollutants. 

Indoor Air

Although environmental indicators have been developed for

some aspects of indoor air, significant gaps exist in knowledge

about the conditions inside the nation’s buildings. For schools

and residences, a large amount of information on indoor air

quality is available, but it comprises primarily case studies and

small, at best, regional studies. More comprehensive data from

national exposure studies for schools and residential indoor

environments, including multiple-family residences, would be

helpful in understanding the condition of indoor air environments. Ideally, such studies would collect exposure data on air

toxics and particulate matter in those indoor environments, as

well as data for molds and other biological contaminants found

in indoor air. 

Global Issues

In general, high quality data

exists with which to predict the

human health effects of increased ultraviolet exposure resulting

from depletion of the stratospheric ozone. These include robust

satellite data on stratospheric ozone concentrations and UV levels, comprehensive and well documented incidence and mortality

rates for cutaneous melanoma, and well characterized action

spectra for skin cancers and cataracts. However, there are areas

where additional data would be useful. First, no national system

exists that collects incidence data for squamous cell carcinoma

and basal cell carcinoma, the non-melanoma skin cancers caused

by increased UV exposure. Thus, our incidence estimates are

modeled using data from a nation-wide survey of non-melanoma

skin cancer incidence and mortality, and may not represent the

most current non-melanoma skin cancer rates. Second, there is

a lack of adequate ground level UV monitoring with which to

compare the satellite data. Satellites cannot directly measure

ground level UV, and are sensitive to pollution. Therefore, while

satellite data compare fairly well to ground level UV measurements in clean locations, this is not the case in polluted areas.

Additional UV monitoring in cities is crucial to support future

epidemiological research on the human health effects of UV

exposure. Third, increased UV levels have been associated with

other human and non-human endpoints including immune suppression and effects on aquatic ecosystems and agricultural

crops. However, additional research on these topics is necessary

before these effects can be modelled or quantified. Finally, the

future behavior of the ozone layer will be affected by changing

atmospheric abundances of various atmospheric gases. It

remains unclear how these changes will affect the predicted

recovery of the ozone layer. Additional research on the interaction between climate and stratospheric ozone could provide

more accurate predictions of ozone recovery and the human

health effects resulting from ozone depletion.

Limitations of Air Indicators

Limitations of Air Indicators
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EPA’s Draft Report on the Environment 2003

Endnotes

1 U.S. Environmental Protection Agency. Latest Findings on

National Air Quality: 2001 Status and Trends, EPA 454-K-02-

001. Research Triangle Park, NC: U.S. Environmental

Protection Agency, Office of Air Quality Planning and

Standards, September 2002.

2 Ibid.

3 Ibid. 

4 U.S. Environmental Protection Agency. National Air Quality

and Emissions Trends Report, 1997. Table A-15. EPA 454-R-98-

016. Research Triangle Park, NC: U.S. Environmental

Protection Agency, Office of Air Quality Planning and

Standards, December 1998.

5 U.S. Environmental Protection Agency. Air Trends:

Metropolitan area trends, Table A-17. 2001. (February 25,

2003; http://www.epa.gov/airtrends/metro.html).

6 U.S. Environmental Protection Agency. Latest Findings on

National Air Quality: 2001 Status and Trends, September

2002. op. cit.

7 Roper A.S.W. Roper Green Gauge Report. 2002. (February

14, 2003; http://www.roperasw.com). 

8 U.S. Environmental Protection Agency. Latest Findings on

National Air Quality: 2001 Status and Trends, September

2002. op. cit.

9 Ibid. 

10 Ibid.

11 Ibid.

12 U.S. Environmental Protection Agency. EPA Acid Rain

Program: 2001 Progress Report, EPA 430-R-02-009.

Washington, DC: U.S. Environmental Protection Agency,

Office of Air and Radiation, November 2002.

13 U.S. Environmental Protection Agency. Latest Findings on

National Air Quality: 2001 Status and Trends, September

2002. op. cit.

14 U.S. Environmental Protection Agency, Office of Air and

Radiation, Technology Transfer Network. National air toxic

assessment: summary of results. September 18, 2002

(January 27, 2003;

http://www.epa.gov/ttn/atw/nata/risksum.html).

15 U.S. Environmental Protection Agency. Latest Findings on

National Air Quality: 2001 Status and Trends, September

2002. op. cit.

16 Ibid.

17 U.S. Environmental Protection Agency. EPA Acid Rain

Program: 2001 Progress Report, November 2002. op. cit. 

18 Ibid. 

19 U.S. Environmental Protection Agency. Latest Findings on

National Air Quality: 2001 Status and Trends, September

2002. op. cit.

20 U.S. Environmental Protection Agency. Air Quality Criteria

for Ozone and Related Photochemical Oxidants, EPA 600-P-93-

004aF-cF. Research Triangle Park, NC: U.S. Environmental

Protection Agency, Office of Research and Development,

National Center for Environmental Assessment, July 1996. 

21 U.S. Environmental Protection Agency. Air Quality Criteria

for Oxides of Nitrogen, EPA 600-8-91-049aF-cF. Research

Triangle Park, NC: U.S. Environmental Protection Agency,

Office of Research and Development, Environmental Criteria

and Assessment Office, August 1993.

22 U.S. Environmental Protection Agency. Air Quality Criteria

for Particulate Matter and Sulfur Oxides, EPA 600-P-82-020ac. Research Triangle Park, NC: U.S. Environmental Protection

Agency, Office of Research and Development, Environmental

Criteria and Assessment Office, 1982.

Endnotes
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Chapter 1 - Cleaner Air

EPA’s Draft Report on the Environment 2003

23 U.S. Environmental Protection Agency. Second Addendum to

the Air Quality Criteria for Particulate Matter and Sulfur Oxides

(1982): Assessment of Newly Available Health Effects

Information, EPA-450-5-86-012. Research Triangle Park, NC:

U.S. Environmental Protection Agency, Office of Research and

Development, Environmental Criteria and Assessment Office,

1986.

24 U.S. Environmental Protection Agency. Supplement to the

Second Addendum (1986) to Air Quality Criteria for Particulate

Matter and Sulfur Oxides (1982): Assessment of New Findings on

Sulfur Dioxide Acute Exposure Health Effects in Asthmatic

Individuals, EPA 600-FP-93-002. Research Triangle Park, NC:

U.S. Environmental Protection Agency, Office of Research and

Development, Office of Health and Environmental

Assessment, Environmental Criteria and Assessment Office,

August 1994.

25 McConnell, R., K. Berhane, F. Gilliland, S.J. London, T. Islam,

W. Gauderman, A. James, M. Edward, H.G. Margolis, and J.M.

Peters. Asthma in exercising children exposed to ozone: a

cohort study. The Lancet 359: 386-391 (2002).

26 U.S. Environmental Protection Agency. Air Quality Criteria

for Carbon Monoxide, EPA 600-P-99-001F. Research Triangle

Park, NC: U.S. Environmental Protection Agency, Office

Research and Development, National Center for

Environmental Assessment. June 2000. 

27 U.S. Environmental Protection Agency. Air Quality Criteria

for Particulate Matter, EPA 600-P-95-001aF-cF.3v. Research

Triangle Park, NC: U.S. Environmental Protection Agency,

Office of Research and Development, National Center for

Environmental Assessment, April 1996.

28 Ibid.

29 U.S. Environmental Protection Agency. Air Quality Criteria

for Particulate Matter, Third External Review Draft, Volume II, EPA

600-P-99-002bC. Research Triangle Park, NC: U.S.

Environmental Protection Agency, Office of Research and

Development, National Center for Environmental Assessment,

April 2002.

30 Pope, C.A., III, R.T. Burnett, M.J. Thun, E.E. Calle, D. Krewski,

K. Ito, and G.D. Thurston. Lung cancer, cardiopulmonary mortality, and long-term exposure to fine particulate air pollution.

Journal of American Medical Association 287: 1132-1141

(2002).

31 U.S. Environmental Protection Agency. Latest Findings on

National Air Quality: 2001 Status and Trends, September

2002. op. cit.

32 U.S. Environmental Protection Agency. Regulatory Impact

Analysis for the Petroleum Refinery NESHAP, EPA 452-R-95-

004. Research Triangle Park, NC: U.S. Environmental

Protection Agency, Office of Air Quality Planning and

Standards, July 1995.

33 U.S. Environmental Protection Agency. Latest Findings on

National Air Quality: 2001 Status and Trends, September

2002. op. cit.

34 U.S. Environmental Protection Agency. EPA Acid Rain

Program: 2001 Progress Report, November 2002. op. cit. 

35 U.S. Department of Health and Human Services, National

Center for Health Statistics. Healthy People 2000 Final Review,

DHHS Publication No. 01-0256. Hyattsville, MD: Public

Health Service, October 2001.

36 U.S. Environmental Protection Agency. National Residential

Radon Survey: Summary Report, EPA-402-R-92-011.

Washington, DC: U.S. Environmental Protection Agency,

Office of Air and Radiation, October 1992.

37 Girman, J.R., G.E. Hadwen, L.E. Burton, S.E. Womble, and J.F.

McCarthy. “Individual volatile organic compound prevalence

and concentrations in 56 buildings of the building assessment survey and evaluation (BASE) study.” In Proceedings of

the 8th International Conference on Indoor Air Quality and

Climate. Indoor Air 2: 460-465 (1999). London, UK:

Construction Research Communications, Ltd. 

Endnotes
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Endnotes

38 Burton, L.E., J.G. Girman, and S.E. Womble. “Airborne particulate matter within 100 randomly selected office buildings

in the United States (BASE).” In Proceedings of Healthy

Buildings 2000 1: 157-162 (2000). Helsinki, Finland: SIY

Indoor Air Information OY.

39 National Research Council. Health Effects of Exposure to

Radon: BEIR VI; Sixth Committee on Biological Effects of Ionizing

Radiation. Washington, DC: National Academies Press, 1998.

40 Scientific Assessment Panel of the Montreal Protocol on

Substances that Deplete the Ozone Layer. Scientific

Assessment of Ozone Depletion: 2002, Executive Summary,

Report No. 47. Geneva, Switzerland: World Meteorological

Organization, Global Ozone Research and Monitoring Project,

2003.

41 National Aeronautics and Space Administration. Ozone

Levels Over North America - NIMBUS-7/TOMS. March 1979

and March 1994. (January 24, 2003;

http://www.epa.gov/ozone/science/glob_dep.html).

42 Scientific Assessment Panel of the Montreal Protocol on

Substances that Deplete the Ozone Layer. Scientific

Assessment of Ozone Depletion: 2002, Executive Summary,

2003. op. cit.

43 DeMora, S., S. Demers, and M. Vernet. The Effects of UV

Radiation in the Marine Environment, Cambridge, UK:

Cambridge University Press, 2000.
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Chapter 2 -

Purer Water
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Introduction

Introduction

P

ristine waterways, safe drinking water, lakes for swimming

and catching fish, and aquatic life habitat are treasured

resources. The nation has made significant progress in

protecting these resources in the last 30 years. Many

Americans remember the burning of the severely polluted

Cuyahoga River in the late 1960s, and the strong actions

taken by many to reduce pollution to the nation’s waters in

the years since. 

These actions have resulted in real progress, but water pollution problems and threats to surface and drinking water

remain. For example, the aging of the nation’s wastewater and

drinking water infrastructure has highlighted the need to

ensure that these critical resources are managed in a sustainable way. Other threats to water resources include landscape

modification, invasive species, changes to water flow, overharvesting of fish and shellfish, and deposition of pollutants from

the air.

This chapter describes what is known about the condition of

waters, watersheds, coastal waters, and wetlands nationwide;

the quality of the nation’s drinking water; the condition of

waters used for recreation; and the condition of waters supporting fish and shellfish consumption. Because the data are

lacking—and often inconsistent—the picture is not complete. The chapter, therefore, also discusses the shortcomings

of the data and the challenges that remain. 

Chapter 2: Purer Water

Waters and Watersheds

Drinking Water

Recreation in and 

on the Water

Consumption of

Fish and Shellfish

Limitations of

Water Indicators
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EPA’s Draft Report on the Environment 2003

Waters and Watersheds

Waters and Watersheds

Awatershed is a geographic area in which all the water

drains to a common waterbody (e.g., river, lake, or

stream). Watersheds may be as small as a few acres or

larger than several states. For example, the Chesapeake Bay

watershed extends across six

states and the District of

Columbia, whereas a small

stream running through a

farmer’s field in Pennsylvania

may drain only a few acres

within the larger

Susquehanna River watershed, which is a portion of

the even larger Chesapeake

Bay watershed. 

Healthy watersheds lead to

cleaner water. Maintaining

that health requires careful

identification and management of human and natural

activities that affect water.

Although federal and state

governments provide technical and financial support for

watershed protection and

restoration efforts, local

stakeholders have led many

such efforts. 

Details on the extent of the

nation’s water resources

(e.g., lakes, ponds, reservoirs,

streams, rivers, wetlands,

Great Lakes, and coastal

areas) can be found in the

Introduction of this report

(see Exhibit i-2, “U.S.

Environmental Protection in

Context”). 

Ground Water 

Of all the fresh water that

exists, about 75 percent is

estimated to be stored in polar ice and glaciers, about 25

percent is estimated to be stored as ground water, and less

than 1 percent is stored as surface water. Ground water is the

source of much of the water used for irrigation, is the principal reserve of fresh water, and represents much of the potential future water supply. It is a major contributor to flow in

many streams and rivers. Indeed, hydrologists estimate that

the ground water contribution to stream flow in the eastern

U.S. may be as large as 40 percent.1 Underground aquifers

(or ground water) supply drinking water to about 50 percent

of the U.S. population.2

Approximately 77 billion gallons per day of fresh ground

water was pumped in the U.S. in 1995.3 This amounts to

about 18 percent of the estimated 1 trillion gallons per day

of natural recharge to the nation’s ground water systems.4

The availability of ground water varies widely on a local scale. 

Waters and

Watershed

Indicators

Water clarity in coastal waters

Dissolved oxygen in coastal waters

Benthic Community Index (coastal)

Wetland extent and change

Sources of wetland change/loss

Altered fresh water ecosystems

Percent urban land cover in 

riparian areas

Agricultural lands in riparian areas

Changing stream flows

Atmospheric deposition of nitrogen

Nitrate in farmland, forested, and

urban streams and ground water

Total nitrogen in coastal waters

Phosphorous in farmland, forested,

and urban streams

Total phosphorous in coastal waters

Phosphorous in large rivers

Atmospheric deposition of mercury

Chemical contamination in streams

Sediment contamination of 

inland waters

Sediment contamination of 

coastal waters

Pesticides in farmland streams and

ground water

Toxic releases to water of mercury,

dioxin, lead, PCBs, and PBTs

Water Quality Standards

The Clean Water Act sets a national goal to restore and protect the

biological, chemical, and physical integrity of the nation’s waters.

Meeting that goal involves maintaining water quality that protects balanced indigenous populations of fish, shellfish, and wildlife and preserves recreational use of those waters. States, territories, and

authorized tribes have the authority and responsibility to establish

water quality standards for their waters. EPA assists by developing recommendations for criteria to protect human health and aquatic life.

Pollutant standards are not the same from state to state because they

address different designated uses and government policies, variations

in natural conditions and ecosystem characteristics, and geological

influences on the natural chemistry of water.
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Waters and Watersheds

What is the condition of waters

and watersheds in the United

States?

At this time, there is not sufficient information to provide a

national answer to this question with confidence and scientific credibility. A great deal is currently known, however, about

the condition of regional, state, and local waters due to the

tremendous monitoring efforts of state and local authorities

and watershed groups and citizens. What they have learned

from these efforts has been useful in managing water

resources. 

States, territories, and authorized tribes have major responsibilities under the Clean Water Act, including the task of

assessing the quality of their waters. That information is compiled by EPA and sent to Congress every two years in the

National Water Quality Inventory. The assessments performed

under Section 305(b) of the Act are to determine if water

quality is supporting “designated uses” in state water quality

standards. Typically, water quality is protected for use by

aquatic life, for use as drinking water supplies, to support

water for fish and shellfish for consumption, and for recreational, agricultural, industrial, and domestic uses.

Yet a number of factors limit what the Section 305(b) data

can say about condition at the national level. Most states,

territories, and tribes collect data and information on only a

portion of their waterbodies. Also, their programs, sampling

techniques, and standards differ. Many have targeted their

monitoring programs to known problem areas. Although the

use of targeted sampling informs local decision-making, it

does not present a comprehensive understanding of the condition of water resources.

To confidently assess the condition of the nation’s waters

using regional and state information, a consistent, representative sample design and comparable data collection and analysis procedures are needed. A number of states are

implementing such programs (see box, “New Directions in

State Water Quality Assessment Programs”). 

A number of other programs collect information that contributes to our understanding of the condition of the nation’s

waters (see box “Who Is Assessing Water and Watershed

Conditions?”). Many of them specifically address the imporNew Directions in State Water Quality Assessment Programs

■ In its “2002 State of the Environment Report,”5 the Indiana Department of Environmental Management used a statistical

survey to report stream-water quality assessments by major watersheds. Since 1996, the department’s Watershed Monitoring

Program has assessed 20 percent of the state’s streams each year for their ability to support aquatic life. Indiana completed

the first comprehensive assessment of more than 99 percent of its streams and rivers in 2001. Of the 35,430 stream miles

assessed, approximately 64.5 percent were estimated to fully support the maintenance of well-balanced aquatic communities. 

■ Maryland Biological Stream Survey (MBSS) uses a probability-based survey design to assess the status of biological resources

in Maryland’s non-tidal streams. In the fifth year of the survey, it intends to (1) characterize biological resources and ecological conditions, (2) assess their condition, and (3) identify the likely sources of degradation. The state has developed an interim framework to apply “biocriteria” in its water quality inventory (its 305[b] report) and list of impaired waters (its 303[d]

list). To date, the proposed biocriteria rely on two biological indicators from the MBSS, the Fish and Benthic Indices of Biotic

Integrity. (Benthic organisms include worms, clams, and crustaceans that live at the bottom of streams, lakes, ponds, estuaries,

and the sea.) A preliminary evaluation using MBSS 2000 data was conducted to identify watersheds that fail to meet the

requirements of the interim biocriteria framework. For a portion of the state, three larger watersheds that were assessed passed,

and six assessments were inconclusive. Of the 123 sub-watersheds studied, 69 failed, 32 passed, and 22 were inconclusive.

■ Kentucky has published the results of probabilistic surveys on the first three of its basin management units. The state’s 2004 water quality report

is expected to include results of additional surveys covering the watersheds of the entire state.

■ Other statistically designed studies are under way in Alabama, Delaware, Florida, Idaho, Iowa, Kansas, Minnesota, Mississippi, Missouri, Nebraska,

New Jersey, Oregon, South Carolina, Virginia, West Virginia, and Wisconsin. The studies will allow those states to provide statewide characterizations of the waters being sampled.
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Waters and Watersheds

tance of watersheds as geographical groupings of waters and

landscapes. This allows a better characterization of conditions

than focusing on the waters alone, as well as a better understanding of how stressors affect water quality and the plants

and animals that depend on water. An improved ability to

report nationally on the condition of surface waters would

also require a collaboration of states, tribal authorities, and

federal agencies. 

What is the condition of coastal

waters?

The 2001 National Coastal Condition Report found the

nation’s estuaries to be in “fair” to “poor” condition, varying

from region to region (Exhibit 2-1). The study determined

the overall condition of the estuaries based on measurements

of seven coastal condition indicators: eutrophication, dissolved oxygen, water clarity, sediments, benthic condition,

fish contamination, and loss of coastal wetlands. No overall

assessments were completed for Alaska, Hawaii, or the island

territories. 

Estuaries are the most productive surface waters for plant

and animal life. Near-coastal habitats provide critical spawning

grounds, nurseries, shelter, and food for fish, shellfish, birds,

and other wildlife. Coastal areas also provide essential nesting, feeding, and breeding habitat for 85 percent of the

nation’s waterfowl and other migratory birds.6 Benthic organisms are important to the food chain. They are also key indicators of the health of coastal waters because they do not

migrate and tend to have more concentrated interactions with

their surroundings (e.g., sediment, water) than do many fish

(Exhibit 2-1).

All seven indicators can help describe the condition of the

nation’s estuaries and near-coastal waters in more detail; this

report focuses on three of them: eutrophication, dissolved

oxygen, and water clarity.

Eutrophication

Eutrophication is a natural

process characterized by a

high rate of algal production. In recent years, human activities

have substantially increased the delivery rate of nutrients to

Who Is Assessing Water and Watershed

Conditions?

■ The U.S. Geological Survey’s (USGS’s) National Water-Quality

Assessment (NAWQA) Program is a perennial program designed to

provide consistent descriptions of the status and trends in some of

the largest and most important streams and aquifer systems of the

nation and to link the status and trends with an understanding of

the natural and human factors that affect the quality of water. The

studies cover 42 large hydrologic systems; however, the sampling for

surface waters may not present statistically valid data for those systems. 

■ EPA’s Environmental Monitoring and Assessment Program (EMAP)

has conducted representative sampling of estuarine and stream

resources, and then incorporated biological measures in estimates of

condition. In most cases, however, those were one-time only assessments. In addition, geographic coverage for fresh water resources is

limited to the mid-Atlantic region and the western states. Also,

studies of estuarine resources were primarily limited to eastern areas

south of Cape Cod, Gulf of Mexico coastal areas, and some western

states. 

■ The National Oceanic and Atmospheric Administration’s (NOAA’s)

National Status and Trends Program collects information on the

chemical contamination of sediments and organisms, and on potential biological effects in the nation’s coastal areas. Although the

NOAA coastal studies of chemicals in sediments and bivalve tissues

are multiyear in nature, most of the detailed chemical and toxicity

assessments of estuarine areas are single point-in-time studies that

were not meant to be repeated.

■ The Natural Resources Conservation Service’s (NRCS’s) National

Resources Inventory (NRI) is a statistically based sample of land

use and natural resource conditions and trends on U.S. non-federal

lands. NRI periodically collects data on land cover and use, soil

erosion, prime farmland soils, wetlands, habitat diversity, selected

conservation practices, and related resource attributes. No samples

are taken on federally owned land.

■ The U.S. Fish and Wildlife Service’s (USFWS’s) National Wetlands

Inventory produces information on the characteristics, extent, and

status of the nation’s wetlands. 

■ Other major watershed protection programs collect data of local

significance. The EPA Great Lakes National Program Office, for

example, conducts statistically based monitoring of the open waters

of the five Great Lakes covering trophic (nutrient level) conditions,

nutrient concentrations, and biological indicators. Similar programs

are found in the Chesapeake Bay, the Florida Everglades, Long

Island Sound, and other areas. Atmospheric deposition of nutrients

and toxic contaminants is monitored in many of these watersheds as

well. 
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Waters and Watersheds

many coastal waters, resulting in greater algal production than

would have occurred naturally. A NOAA survey between 1992

and 1998 assessed symptoms of eutrophication, including

high levels of algae and toxic algal blooms, lack of oxygen,

and loss of aquatic plants that provide shelter and habitat for

many species of bottom-living organisms (Exhibit 2-2).7

Although the assessments were more a subjective determination of expert opinion than a systematic data analysis, they

suggest that 40 percent of U.S. estuarine waters—as measured by surface area—are degraded by excess nutrients. That

condition can lead to high levels of algae, and eventually to

lower levels of oxygen in the water. 

Overall National

Condition of Estuaries

and Great Lakes

Ecological Health

Water Clarity

Dissolved Oxygen**

Coastal Wetlands

Eutrophic Condition

Sediment

Benthos

Fish Tissue

No indicator data available. ** Does not include the hypoxic zone in offshore Gulf of Mexico waters. Note: no assessments were completed for Alaska, 

Hawaii, or island territories.

Source: EPA, Office of Research and Development and Office of Water. National Coastal Condition Report. September 2001.

Exhibit 2-1: Overall condition of estuaries and Great Lakes, 2000

Overall

West

Overall

Gulf

Overall

Southeast

Good Fair Poor

O

Good Fair Poor

O

Good Fair Poor

O

Overall

Great Lakes

Good Fair Poor

O

Overall

Northeast

Good Fair Poor

O

Good Fair Poor

O

Low

High

Moderate

Exhibit 2-2: Percent of estuaries with high, moderate, and 

low levels of eutrophic condition, 1998

Source: Bricker, S.B. et al. National Estuarine Eutrophication Assessment: Effects of 

Nutrient Enrichment in the Nation's Estuaries.1999; EPA, Office of Research and 

Development and Office of Water. National Coastal Condition Report. September 

2001.

25%

35%

40%
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Waters and Watersheds

Dissolved Oxygen

Dissolved oxygen is a fundamental requirement for aquatic

life. Low levels of dissolved oxygen, a condition called “hypoxia,” are a problem in some coastal areas. This condition

occurs when too many nutrients flow into coastal waters,

overstimulating the growth of algae. The organic matter produced by the algae eventually decomposes, using up oxygen

in the process. Hypoxia can contribute to algal scums, fish

kills, noxious odors, habitat loss, and diminished aesthetic

values. During hypoxic periods—which usually occur in the

summer when high temperatures impede the mixing of oxygen

from surface to deeper layers—dissolved oxygen levels fall

below 2 parts per million (ppm, or 2 milligrams per liter

[mg/L]), well below the 5 ppm needed to support healthy

populations of aquatic life.8 As oxygen levels fall, the effects

on aquatic life become more severe. At about 3 ppm, bottomliving fish start to leave the area and the growth of some

species is reduced. At levels less than 2 ppm, some juvenile

fish and crustaceans start to die. At levels less than 1 ppm,

fish totally avoid the area or begin to die in large numbers. 

Generally, dissolved oxygen conditions in the nation’s estuaries are good, judging from data gathered through EMAP.

Similarly, according to the National Coastal Condition Report,

80 percent of sampled estuaries were in good condition with

respect to levels of dissolved oxygen (more than 5 ppm dissolved oxygen), and 4 percent were in poor condition (less

than 2 ppm dissolved oxygen). Low dissolved oxygen levels,

however, are a seasonal problem in many estuarine systems

such as the Neuse River Estuary in North Carolina and parts

of Chesapeake Bay, Long Island Sound, and Tampa Bay.

Further, although the report describes dissolved oxygen conditions in Gulf of Mexico estuaries as good, it also describes a

hypoxic zone about the size of Massachusetts in the offshore

waters of the northern Gulf (see box, “Hypoxia in the Gulf of

Mexico and Long Island Sound”). 

Water Clarity

Water clarity, measured as the

distance light penetrates into

water, is another important characteristic of estuarine and

coastal habitats and of all surface waters. Reduced light penetration is often the result of rainstorms, runoff from farmland

and urban areas, eutrophic conditions, and algal blooms.

Reduced clarity can impair normal algal growth and both the

extent and vitality of submerged aquatic vegetation, which is

a critical habitat component for many aquatic animals. EMAP

data indicate that, overall, the nation’s estuaries have good

water clarity.

What are the extent and

condition of wetlands?

Wetlands provide critical habitat, breeding grounds, resting

places, and sources of food for fish, shellfish, birds, and other

wildlife. They also filter pollutants, which helps protect water

quality, limit flooding, and buffer coastal areas from storm

damage. An estimated 95 percent of commercial fish and 85

percent of sport fish spend a portion of their lives in coastal

wetlands.9 Shellfish—shrimp, crab, and oysters—also rely on

healthy wetlands for food and habitats.

Wetland extent serves as a partial surrogate to address wetland condition. The loss of wetlands in the landscape has a

negative impact on the condition of the remaining wetlands

by decreasing the physical connections among aquatic

resources and decreasing diversity of the landscape, which

lead to diminished opportunity for biological exchange and

increased habitat fragmentation. 

In 1997, the conterminous U.S. had approximately 105.5

million acres of wetlands, less than half the 220 million acres

that likely existed in 1600. Nearly 95 percent, or 100.2 million acres, of those wetlands are fresh water, and about 5 percent—5.3 million acres—are intertidal marine and estuarine

water.10 Based on estimates made in the late 1980s, Hawaii

had 51,800 acres of wetlands, and Alaska had 170 million.11

Exhibit 2-5 portrays the loss of wetlands since the mid1950s. Until the 1970s, conversion to agricultural lands was

the predominant cause of wetland loss. Since then, rates of

annual wetland losses have been dropping—from almost

500,000 acres to less than 100,000 acres averaged annually

since 1986. The U.S. Fish and Wildlife Service National

Wetlands Inventory survey estimated the annual rate of loss

at 58,500 acres per year between 1986 and 1997. That represents an 80 percent reduction in the rate of loss from the

previous decade.12
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Waters and Watersheds

Hypoxia in the Gulf of Mexico and Long Island Sound

The area and duration of hypoxia are tracked in the Gulf of Mexico and Long Island Sound as indicators of the natural variability in those waterbodies to determine whether actions to control nutrients are having the desired effect and how local species are affected. 

The largest zone of oxygen-depleted coastal waters in the U.S. is in the northern Gulf of Mexico on the Louisiana/Texas continental shelf. Hypoxic

waters are most prevalent from late spring through late summer and are more widespread and persistent in some years than in others, depending on

river flow, winds, and other environmental variables. Hypoxia occurs mostly in the lower water column, but can encompass as much as the lower half to

two-thirds of the entire column. 

The midsummer bottom areal extent of hypoxic waters in the Gulf of Mexico increased from 3,500 square miles (9,000 square kilometers) in 1985

to 8,500 square miles (22,000 square kilometers) in July 2002 (Exhibit 2-3). The primary cause of the hypoxic conditions is probably the

eutrophication of those waters from nutrient enrichment delivered to the Gulf by the Mississippi River and its drainage basin.13,14

The maximum area of hypoxia in Long

Island Sound averaged 201 square

miles (521 square kilometers) from

1987 through 2001. The largest area

was 395 square miles (1,023 square

kilometers) in 1994, and the smallest

was 30 square miles (78 square kilometers) in 1997 (Exhibit 2-4). The duration of hypoxia averaged 56 days

during the same period, with a low of

34 days in 1996 and a high of 82 days

in 1989. Hypoxia is typically more

severe in the western portions of the

sound, where the nitrogen load is higher

and mixing of fresh and salt water is

more restricted.15 Square Kilometers

20,000

(7,772 square miles)

25,000

(9,702 square miles)

15,000

(5,792 square miles)

10,000

(3,861 square miles)

5,000

(1,930 square miles)

19851986198719881989

No 

Data

1990199119921993199419951996199719981999200020012002

Exhibit 2-3: Areal extent of midsummer hypoxia in the Gulf of Mexico, 1985–2002

Note: Hypoxia in the Gulf is defined as less than 2.0 parts per million (ppm).

Annual midsummer cruises have been conducted systematically over the past 15 years (with the exception of 1989). Hypoxia in bottom waters covered an average of 

8,000-9,000 km in 1985-92 but increased to 16,000-20,000 km in 1993-99.

Source: For 1985-1999 data years: Rabalais, Nancy N. et al. Characterization of Hypoxia: Topic 1 Report for the Integrated Assessment on Hypoxia in the Gulf of Mexico. May 

1999, updated July 2000; for 2000-2002 data years: Rabalais, Nancy N., Louisiana Universities Marine Consortium. Unpublished data, personal communication. 

February 11, 2003.

Exhibit 2-4: Maximum area and duration of hypoxia in Long Island Sound, 1987–2001 Square Miles Days

450 90

80

70

60

50

40

30

20

10

0

350

250

150

100

200

300

400

50

19871989199119931995199719992001

0

Note: Hypoxia in Long Island Sound is defined as less than 3.0 parts per million (ppm).

Source: EPA, Long Island Sound Office. Sound Health 2001: Status and Trends in the Health of Long Island Sound. 2001.

Area of hypoxia Duration of hypoxia
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Waters and Watersheds

Between 1986 and 1997, 98 percent of all wetland losses in

the conterminous U.S. were fresh water wetlands. Since the

1950s, fresh water emergent wetlands (marshes) have

declined by nearly 24 percent, and 10.4 million acres of fresh

water forested wetlands have been lost. Coastal and estuarine

losses during the same time were much lower on an absolute

scale—about 1.4 million acres—but that loss represents a

nearly 12 percent decline in coastal and estuarine wetlands.16

Loss of land to open water is a particular problem in

Louisiana, whose 3.5 million acres of coastal wetlands represent about 40 percent of all of the coastal wetlands in the

continental U.S. The state has lost more than 600,000 acres

of coastal vegetated wetlands and is now losing coastal wetlands at an average annual rate of 16,000 to 19,000 acres

per year.17 In addition to flood controls and altered channels

to facilitate navigation, rising sea level, marshland sloughing

(sections breaking off) into deeper bays and sounds, and

land subsidence (sinking) may have contributed to those

losses.18

Additionally, major ecological effects have occurred from the

conversions of one wetland type to another: clearing trees

from a forested wetland or excavating a shallow marsh to create an open water pond, for example. Such conversions

change habitat types and community structure in watersheds

and have an impact on the plant and animal communities that

depend on them.

What are stressors to waters

and watersheds?

Stressors affecting waters include alteration of natural water

ecosystems, excess nutrients, toxic chemicals, and viruses and

bacteria (pathogens, which are described in the following sections covering Drinking Water, Recreation in and on the Water,

and Consumption of Fish and Shellfish). Some human activities associated with these stressors are illustrated in Exhibit

2-6. The indicators presented here to identify water stressors

are drawn from national surveys or assessments. There are,

however, strong indications from state-reported causes of

impaired waters that stressors responsible for locally degraded water quality include sediments from non-point sources,

nutrients from point and non-point sources, pathogens from

point and non-point sources, and metals—largely as a result

of point source discharges from years ago and atmospheric

deposition.19 All these conditions and situations may harm

humans and aquatic species, reduce recreational opportunities, and increase the treatment costs for drinking water. 

Under the Clean Water Act, states evaluate their waters and

list impaired waters for potential reductions in point and nonpoint sources or for habitat restoration. In 1998, more than

20,000 waterways were identified as impaired under Section

303(d) of the Clean Water Act.20 States have identified the

principal causes of such impairments as siltation, pathogens,

metals (particularly mercury), nutrients, habitat alteration,

pesticides, organic enrichment/low dissolved oxygen, thermal

modifications, low or high pH, and fish consumption advisories. The major transport mechanism for mercury is atmospheric deposition, which is also a significant source of

nitrogen to waters. 

Losing natural areas adjacent to waterbodies—and forested

areas to development and agricultural activities—raises concerns about both water quality and quantity, especially in

fast-growing areas such as the southeastern U.S. When impervious surfaces—asphalt and concrete, for example—impede

or accelerate natural flows, water cannot percolate through

soil. As a result, rain water rushes off, picking up pollutants

and overwhelming local streams. Recent trends toward lowdensity development leave fewer pristine natural areas and

100,000

0

200,000

300,000

400,000

500,000

600,000

1954–74 1974–83 1986–97 Acres

458,000

290,000

58,500

Exhibit 2-5: Average annual wetland loss, 

1954–1974, 1974–1983, 1986–1997

Source: Frayer, W.E. et al. Status and Trends of Wetlands and Deepwater Habitats in 

the Conterminous United States 1950s to 1970s. 1983; Dahl, T.E. and C.E. Johnson. 

Wetland Status and Trends in the Conterminous United States 1970's to 1980's. 

1991; Dahl, T.E. Status and Trends of Wetlands in the Conterminous United States 

1986 to 1997. 2000.
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Waters and Watersheds

fewer trees and expose more land to pesticides and chemical

fertilizers. (For a more detailed discussion of those stressors,

see the “Land Use” section of Chapter 3 – Better Protected

Land.)

Physical alteration of a waterbody—damming or cutting

channels in a river, or developing along shorelines or on adjacent wetlands—can have significant effects on water and on

aquatic life. Although waterbodies are usually modified to

achieve some gain—flood control, easier navigation, reduced

erosion, or more area for farming or development—such

alterations may also reduce fish and wildlife habitat, disrupt

the patterns and timing of water flows, block the movement of

wildlife, and reduce or eliminate the natural filtering of sediment and pollutants.

An analysis of rivers, streams, lakes, and reservoirs (excluding

very small streams where data were not collected), based on

remote sensing and U.S. Geological Survey (USGS) data,

found that 23 percent of the stream banks, lake shorelines,

and adjacent wetlands had been altered by use as croplands

or by urban development. The natural habitat and function of

those waterbodies is probably altered as well.21 The data are

not collected in a manner that allows for aggregation to provide a national perspective. At present, data for lakes and

reservoirs are aggregated, even though a reservoir is a manmade structure or seriously altered habitat. Data on the

degree to which streams and rivers are channelized, leveed, or

dammed are not available, but these alterations result in similar impacts. 

Urban and suburban activities

Agricultural practices

Air deposition

Forestry practices

Industrial

activities

Exhibit 2-6: Selected activities affecting water, watersheds, and drinking water resources
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Although nitrogen and phosphorus are beneficial plant nutrients, human activities have increased their flow into waterbodies—in some cases to harmful levels. Runoff from farms

and urban and suburban areas, nitrogen from power plants,

emissions from vehicles and industry, and discharges from

sewage treatment plants and septic systems can be sources

of excess nutrients, causing excessive algae and plant growth.

The resulting eutrophication harms aquatic life, fouls swimming beaches, causes odor from excess decaying algae, and

may increase blooms of harmful algae such as red or brown

tides.22

Ground water in agricultural areas often has higher nitrogen

concentrations than that in non-agricultural areas. For example, approximately 10 percent of streams and 20 percent of

wells in farming areas exceed federal drinking water standards

for nitrate.23

Contaminated sediments can be a serious problem in certain

areas and may be associated with industrial activity that predated awareness of the harmful effects of certain pollutants

and the adoption of pollution control programs.24 Pollutants

such as dioxins, mercury, lead, polychlorinated biphenyls

(PCBs), and other persistent bioaccumulative toxic chemicals

in sediments can affect water quality and aquatic life.

Industrial releases of metals, as reported through the Toxics

Release Inventory, remain potential stressors to water quality.

Some toxic sediments kill benthic organisms, reducing the

food available to larger animals such as fish. Some contaminants in sediment are taken up by organisms, which are then

eaten by next-level predators. In that way, contaminants can

move up the food chain in increasing concentrations, affecting fish, shellfish, waterfowl, and mammals, including people. 

The USGS has synthesized contaminant and nutrient data

from its 1992–1998 National Water Quality Assessment

(NAWQA) program on 36 study units. Some of the major

findings include: detectable concentrations of pesticides are

widespread in urban, agricultural, and mixed-use area streams;

streams in urban areas generally have higher concentrations

of insecticides than streams in agricultural areas; elevated

(above background) levels of selected heavy metals are found

in waters; and widespread volatile organic compounds are

seen in shallow urban ground water.25

What ecological effects are

associated with impaired

waters?

Biological communities reflect the cumulative effect of virtually all watershed stressors over time. Waters stressed by increased chemical contamination or altered habitats become

impaired, which changes their structure, composition, and

function. Pollution-sensitive species, along with organisms

that require particular habitats, yield to more pollutiontolerant species and organisms that can adapt to a variety of

habitat alterations and changes. Such changes can ultimately

lead to a loss of aquatic diversity and abundance. 

Several federal, regional, state, and tribal monitoring programs

examine factors that affect aquatic communities. They have

established direct and indirect relationships between the

pressures on a community and its organisms by noting the

changes in the structure, composition, and function of the

animals and plants. Those “biological response signatures”

help provide clues to watershed problems—including the

types and sources of pressures.

The Macroinvertebrate Index of Biotic Integrity (IBI) and the

Fish IBI are examples of such response signatures. They are

indices that can measure incremental changes in the condition of waters and provide clues to the pressures affecting

aquatic communities. IBIs have also been developed for

coastal waters, wetlands, and lakes, and their use is growing at

the regional, state, tribal, watershed, and local levels.26 (See

Chapter 5 – Ecological Condition, for further discussion of

IBIs.) IBIs for benthos were assessed for the Northeast,

Southeast, and Gulf Coastal areas. Assessments showed that

56 percent of the coastal waters were in good condition, 22

percent were in fair condition, and 22 percent were in poor

condition. Of the 22 percent with poor benthic condition, 62

percent also had sediment contamination, 11 percent had low

dissolved oxygen concentrations, 7 percent had low light

penetration, and 2 percent showed sediment toxicity.27
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Drinking Water

Drinking Water

What is the quality of drinking

water?

I

n 2002, state data reported to EPA showed that approximately 251 million people were served by community water

systems that met all health-based standards (i.e., reported

no health-based violations). This number represents 94 percent of the total population served by community water systems, up from 79 percent in 1993 (Exhibit 2-7).28

Underreporting and late reporting of violations data by states

to EPA, however, affect the accuracy of these data. The water

used by community water systems comes from both surface

water and ground water. 

The nation has some 55,000 community water systems (a

subset of all public water systems), all of which must test

their water and treat it as needed to remove contaminants to

specified levels before distributing it to customers. In 2002,

community water systems

served about 268 million people. Large-scale water supply

systems usually rely on surface

waters; smaller water systems

tend to use ground water. Noncommunity water systems are

also required to test and treat

water. There are no national

treatment or monitoring

requirements for private wells.

(The “Ground Water” discussion, under the “Waters and

Watersheds” section of this

chapter, provides more detail

on the use of ground water as

a drinking water resource.)

National drinking water standards apply to public water

systems, which include

municipally or privately

owned water systems, homeowner associations, and

other entities such as some

schools, businesses, campgrounds, and shopping malls

that draw their own water.

National health-based standards exist for about 90 regulated contaminants. These

intensive technical evaluations include many factors: occurrence in the environment; human exposure and risks of harmful health effects in the general population and sensitive

subpopulations; analytical methods of detection; technical

feasibility; and impacts of the regulation on water systems

and public health.

National drinking water standards also prescribe protocols,

frequencies, and locations for monitoring. Water systems

monitor at treatment plants

and also in distribution systems

for contaminants such as disinfection by-products and coliform bacteria that may form or

recur there. Monitoring locations generally depend on the

contaminant of interest.

Annually, community drinking

water suppliers report their

overall water test results to

their customers. Suppliers also

must notify their customers of

violations that pose an immediate threat to health. Noncommunity public water

systems are not required to

provide this annual report but

are required to notify customers when drinking water

standards are violated. 

Fiscal Year

Exhibit 2-7: Population served by community water systems 

with no reported violations of health-based standards, 

1993–2002

Population served by 

CWSs that had no 

reported violations

Percent of CWS-served 

population that was served 

by systems with no reported 

violations

2002

2001

2000

1999

1998

1997

1996

1995

1994

1993

250,596,287

239,927,650

239,299,701

229,805,285

224,808,251

215,351,842

213,109,672

208,700,100

202,626,433

196,229,162

94

91

91

91

89

87

86

84

83

79

Source: EPA, Office of Water. Safe Drinking Water Information Systems/Federal version 

(SDWIS/FED). 2003.

Drinking Water

Indicators

Population served by community

water systems that meet all healthbased standards
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Drinking Water

What are sources of drinking

water contamination?

Microbiological, chemical, and radiological contaminants can

enter water supplies as a result of human activity and release

from natural sources. For instance, chemicals can migrate from

disposal sites or underground storage systems and contaminate sources of drinking water. Animal wastes, pesticides, and

fertilizers may be carried to lakes and streams by rainfall

runoff or snow melt. Nitrates from fertilizers also can be carried by runoff and percolate through soil to contaminate

ground water (see Chapter 3 – Better Protected Land, for

more discussion of nitrates). Arsenic and radon are examples

of naturally occurring contaminants that may be released into

ground water as it travels through rock and soil. 

Human wastes from poorly managed or maintained septic and

sewage systems as well as wastes from animal feedlots and

wildlife carrying microbial pathogens (e.g., Giardia, Cryptosporidium, and E. coli) may get into waters ultimately used for

drinking. All drinking water supply systems in the U.S. that

use surface water or ground water with close hydrological

connections to surface water must disinfect water and most

must also filter it to remove pathogens. Disinfecting drinking

water is a key element of treatment because it provides a barrier against harmful microbes. Disinfectants such as chlorine,

however, react with naturally occurring organic matter in

source water and in distribution systems to form chemical byproducts such as trihalomethane and haloacetic acid compounds. Generally, the older a system’s infrastructure, the

greater the risk for breaches or infiltrations in the distribution

system, which increase the risk of contamination.

What human health effects are

associated with drinking

contaminated water?

The potential health effects of consuming contaminated

drinking water range from minor to fatal. Drinking inadequately treated water could result in nervous system or organ damage, developmental or reproductive effects, or cancer.29

Consuming water with nitrates at sufficiently high levels can

result in potentially fatal alterations in the hemoglobin (the

iron-containing pigment in red blood cells) of infants and

very young children, called “blue baby syndrome.”30 National

standards for public water systems are designed to provide

levels of treatment that are protective against adverse health

effects.

The consequences of consuming water contaminated with

pathogens can include gastrointestinal illnesses that cause

stomach pain, diarrhea, headache, vomiting, and fever (see

box, “Waterborne Disease Outbreaks Associated with

Drinking Water 1971–2000,” and discussions on

“Waterborne Diseases” and “Gastrointestinal Illnesses” in

Chapter 4 – Human Health). A microbial outbreak of

Cryptosporidium in Milwaukee in 1993 sickened about

400,000 people and killed more than 50, most of whom had

seriously weakened immune systems.31

Disinfection of drinking water is one of the major public

health advances of the 20th century and has been a critical

factor in reducing the incidence of waterborne diseases,

including typhoid, cholera, hepatitis, and gastrointestinal illness in the U.S.32 By-products of disinfection have also been

associated with potential cancer, developmental, and reproductive risks, although the extent of risk posed is still uncertain. Limiting concentrations of disinfection by-products in

drinking water, while ensuring that microbes are kept in check,

will have a positive effect on public health. 

The Safe Drinking Water Act

The Safe Drinking Water Act, as amended in 1996, mandates that

EPA, states, and water systems implement multiple barriers to protect

consumers from the risks of unsafe drinking water. Key activities

include protection of source water, development and implementation of

regulations based on sound science and risk assessments, improvements to drinking water infrastructure, certification of water system

operators, technical assistance to water systems, and improving consumer awareness. 
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Waterborne Disease Outbreaks Associated with Drinking Water 1971-2000

Since 1971, the Centers for Disease Control and Prevention (CDC), EPA, and the Council of State and Territorial Epidemiologists have maintained a

collaborative surveillance system for the occurrences and causes of waterborne disease outbreaks (WBDO). These data are only a small part of the

larger body of information related to drinking water quality in the U.S. State, territorial, and local public health agencies are primarily responsible for

detecting and investigating WBDOs and voluntarily reporting them to CDC. These data are used to identify types of water systems, their deficiencies,

the etiologic agents (e.g., microorganisms and chemicals) associated with outbreaks, and to evaluate current technologies for providing safe drinking

water and safe recreational waters. This system reports outbreaks and estimated numbers of people who become ill. It does not provide information on

non-outbreak related or endemic levels of waterborne illness. Moreover, the focus is on acute illness. The system does not address chronic illnesses

such as cancer, reproductive, or developmental effects. CDC and EPA are collaborating on a series of epidemiology studies to assess the magnitude of

non-outbreak waterborne illness associated with consumption of municipal drinking water.

Between 1971 and 2000, there were 751 reported waterborne disease outbreaks associated with drinking water from individual, non-community systems, and community water systems (Exhibit 2-8). During 1999-2000, a total of 44 outbreaks (18 from private wells, 14 from non-community systems, and 12 from community systems) associated with drinking water were reported by 25 states.33

However, these data should be interpreted with caution. Many factors can influence whether a WBDO is recognized and investigated by local, territorial, and state public health agencies. For example, the size of the outbreak, severity of the disease caused by the outbreak, public awareness of the outbreak, whether people seek medical care or report to a local health authority, reporting requirements, routine laboratory testing for organisms, and

resources for investigation can all influence the identification and investigation of a WBDO. This system underreports the true number of outbreaks

because of the multiple steps required before an outbreak is identified and investigated. Thus, an increase in the number of outbreaks reported could

either reflect an actual increase or improved surveillance and reporting at the local and state level.

10

20

30

40

50

60

Exhibit 2-8: Number of reported waterborne disease outbreaks associated 

with drinking water by year and type of water system, United States, 1971–2000 (n=751)

Year

1971

1973 1975

1977

1979

1981

1983

1985

1987

1989 1991 1993

1995

1997

19992000 Number of outbreaks Non-community

Individual

Community

Type of Water System**

*A WBDO is defined as an event in which (1) more than two persons have experienced an illness after either the ingestion of drinking water or exposure to water encountered 

in recreational or occupational settings, and (2) epidemiologic evidence implicates water as the probable source of illness.

**Non-community water systems are systems that either (1) regularly supply water to at least 25 of the same people at least 6 months per year, but not year round (e.g., 

schools, factories, office buildings, and hospitals that have their own water systems), or (2) provide water in a place where people do not remain for long periods of time (e.g., 

a gas station or campground).

Individual water systems are not regulated by the Safe Drinking Water Act and serve fewer than 25 persons or 15 service connections, including many private wells.

Community water systems provide water to at least 25 of the same people or service connections year round.

Source: Based on data presented in Craun, G.F. and R.L. Calderon. Waterborne Outbreaks in the United States,1971-2000. 2003.

Drinking Water
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EPA’s Draft Report on the Environment 2003

Recreation in and on the Water

Recreation in and on the Water

F

ederal, state, and local governments monitor the water

quality at many beaches, and issue advisories or close

beaches when the water is contaminated and may pose

health risks. 

What is the condition of waters

supporting recreational use? 

EPA collects information from 237 agencies on beach closings

and advisories through its National Health Protection Survey

of Beaches, which is one way to measure the condition of

recreational waters. Between 1997 and 2001, the percentage

of beaches affected by advisories or closings rose from 23 to

27 percent. During the same period, the number of local,

state, and federal agencies participating in the survey

increased from 159 in 1997 to 237 in 2001. Survey respondents (primarily for coastal and Great Lakes beaches) reported that beaches were closed or under advisory on more than

19,000 beach days, or about 6 percent of total beach days,

during the 2001 swimming season.34 (The increase in the

percentage of beaches

affected is likely a reflection

of more consistent monitoring and reporting.) 

Because reporting under the

survey is voluntary and data

are drawn primarily from

coastal and Great Lakes

beaches rather than inland beaches, the survey’s reliability as

a national indicator is unknown. Furthermore, monitoring and

reporting vary by state, with some states having very aggressive programs.35

California, for example, has one of the most highly developed

beach monitoring and notification programs in the nation.

State law requires frequent monitoring at high-use beaches

and establishes well-defined thresholds for issuing beach

advisories. A committee made up of state, federal, and local

agency officials, as well as representatives from the environmental community and the Beach Water Quality Workgroup

helps coordinate the efforts.

California beaches are monitored at least once a week, with

some in Southern California monitored 5 to 7 days each

week. Other states generally monitor once a week, although

some monitor twice a month or less. The monitoring involves

testing for several indicators including total coliform bacteria,

fecal coliform, and the EPA-recommended indicator

Enterococcus. If a standard is exceeded, local health departments use various methods to notify the public promptly. 

Recreational Water

Indicators

Number of beach days that

beaches are closed or under

advisory
What are sources of

recreational water pollution?

EPA asks survey respondents to identify the sources of pollution that cause advisories or closings. Without precise information, respondents use their best judgment to identify

sources. In more than half the cases, the source is unknown

(Exhibit 2-9). The most frequently identified source is storm

water runoff that contains harmful contaminants such as bacteria from livestock or pet waste, inadequate sewage treatment, or poorly designed or operated septic systems.36

What human health effects are

associated with recreation in

contaminated waters?

The health effects of swimming in contaminated waters are

usually minor and temporary—sore throats, ear infections,

and diarrhea—but can be more serious, even fatal.

Waterborne microbes can cause meningitis, encephalitis, and

severe gastroenteritis.37 However, data on the effects and

number of occurrences are limited. The number of occurrences may be underreported because people may not link

common symptoms with exposure to contaminated recreational waters and, unless symptoms are debilitating, do not

seek medical attention. Additional research and information

are needed to improve understanding of the types and extent

of health effects associated with swimming in contaminated

waters (For additional information see the discussions on

“Waterborne Diseases” and “Gastrointestinal Illnesses” in

Chapter 4 – Human Health). 

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EPA’s Draft Report on the Environment 2003

Recreation in and on the Water

CSO - Combined Sewer Overflow

SSO - Sanitary Sewer Overflow

POTW - Publicly Owned Treatment Works

Exhibit 2-9: Reported sources of pollution that 

resulted in beach closings or advisories, 2001

Sewage line blockage/break 4% Septic system 3% POTW 1%

SSO 2%

Boat discharge 2%

CSO 3%

Wildlife

10%

Stormwater

runoff

20%

Other

3%

Unknown

52%

Source: EPA, Office of Water. EPA's BEACH Watch Program: 2001 Swimming Season. 

May 2002.
F

ish and shellfish are important and desirable sources of

nutrition for many people. However, chemical and biological (bacteria, pathogens) contaminants can accumulate in fish and shellfish, making it unhealthy to consume

them, especially in large quantities. 

What is the condition of waters

that support consumption of

fish and shellfish?

Most states sample fish in their waters and then issue fish

consumption advisories as a way of informing the public of

risks associated with eating certain types and sizes of fish

from certain waterbodies. Advisories are based on fish tissue

monitoring data collected by states and tribes and are largely

focused on areas of known or suspected contamination. 

In the U.S., 14 percent of the river miles, 28 percent of lake

acreage, and 100 percent of the Great Lakes and their connecting waters are under fish

consumption advisories.38

Those percentages have

increased in recent years

(Exhibit 2-10). The increases

are most likely the result of

more consistent monitoring

and reporting and decreases

in concentration criteria, and

are not necessarily an indication that conditions are

getting worse. 

Fish advisories that limit or

restrict consumption, especially of top-level predators (e.g., walleye and lake trout), are

widespread across the U.S. Advisories are issued for various

contaminants—mercury, dioxin, and PCBs are responsible for

many of the advisories throughout the U.S. In January 2001,

EPA and the U.S. Food and Drug Administration issued a

nationwide advisory for women who are pregnant or may

2-17

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EPA’s Draft Report on the Environment 2003

Consumption of Fish and Shellfish

Consumption of Fish

and Shellfish

Indicators

Percent of river miles and lake acres

under fish consumption advisory

Contaminants in fresh water fish

Number of watersheds exceeding

health-based national water quality

criteria for mercury and PCBs in fish

tissue

Consumption of Fish and Shellfish Percent of total acres or miles under advisory 30

25

20

15

10

199319941995199619971998199920002001

Exhibit 2-10: Trends in percentage of river miles and lake acres under fish consumption advisory, 1993–2001

River Miles

Lake Acres

Source: EPA, Office of Water. Update: National Listing of Fish and Wildlife Advisories. May 2002.
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EPA’s Draft Report on the Environment 2003

Consumption of Fish and Shellfish

become pregnant, nursing mothers, and young children to

limit the consumption of certain species of fish that may contain mercury to one meal per week. The jointly issued nationwide advisory applies to fresh water fish and fish bought from

stores and restaurants (i.e., commercially caught fish, including ocean and coastal fish).

Criteria used to issue advisories vary among states. Some

have more stringent criteria and more robust advisory programs than others. Fish advisory data presented in Exhibit

2-10 are intended to show total number of miles and acres

under advisory—rather than the number of advisories—to

clearly represent the amount of area covered and to track

trends.

Coastal states also identify, survey, and classify waters where

shellfish grow and then prohibit the harvesting of shellfish if

the water quality does not meet certain federal standards.

Data indicate improvements since testing began in 1966. The

percentage of prohibited waters decreased from a high of 26

percent in 1974 to 13 percent in 1995.39 Because the survey

has not been repeated since 1995, information on more

recent conditions is not available.

What are contaminants in fish

and shellfish, and where do

they originate?

Most advisories about fish consumption involve one or more

of five primary contaminants: DDT, PCBs, chlordane, dioxins,

and mercury.40 Mercury is a naturally occurring element that

is present throughout the environment and in plants and animals. Human activity can release some of that mercury,

increasing the amount available to accumulate in humans and

other animals. Mercury, which is detectable in most U.S.

waters, comes from a number of sources (e.g., from burning

fossil fuels and from wastes that create mercury emissions

that settle on land and water). In some areas, mercury contamination is the result of activities and practices that have

ceased. In soils and sediments, bacteria convert mercury to

highly toxic methylmercury, which is absorbed by fish and

accumulates in their tissue.

Some synthetic toxic substances such as DDT and PCBs are

common in fresh and coastal waters. Although manufacture

and use of PCBs and DDT have been banned in the U.S. for

many years, sediments deposited years ago, and residual

amounts in soil, continue to contaminate U.S. watersheds

(Although production ceased in 1997, PCBs can be found in

some products manufactured prior to the ban (e.g., electrical

transformers).41 PCBs, DDT, and mercury can contaminate

fish and shellfish and be carried up the food chain to larger

fish, such as large-mouth bass, tuna, swordfish, and some

sharks. Such concerns led to the nationwide mercury

advisory.

Officials in the Great Lakes region are using a multimedia

approach to focus on persistent toxic chemicals in air, sediments, and fish tissue (see box, “Bioaccumulative Toxics in

the Great Lakes: A Multimedia Look”). Threats to shellfish

also include bacterial contamination from human and animal

wastes and naturally occurring toxins that shellfish accumulate

from consuming certain algae.42 Although closings of shellfish

beds generally result from excessive coliform concentrations,

other pathogens are not always measured and could be a

concern. In addition, state and local agencies use different

procedures to determine what factors (e.g., presence of

chemical contaminants) should be used to dictate closings. 

What human health effects are

associated with consuming

contaminated fish and shellfish?

The effects of eating contaminated fish or shellfish vary

greatly. The greatest risks come from consuming contaminated fish and shellfish regularly over a period of time.

Assessments show a measurable risk of cancer from some

chemical contaminants that are sometimes found in fish tissues (e.g., DDT, PCBs). Mercury is toxic in sufficient quantities, especially to the nervous system. Shellfish contaminated
2-19

Chapter 2 - Purer Water

EPA’s Draft Report on the Environment 2003

Consumption of Fish and Shellfish

Bioaccumulative Toxics in the Great Lakes: A Multimedia Look

Toxic chemicals enter the water of the Great Lakes (and therefore fish)

from the atmosphere, tributaries, and sediments. These chemicals can

be retained by plants and animals and increase in concentration though

the food chain, a process called “bioaccumulation.” Environmental data

and modeling were used to estimate the relative contributions from each

pathway to Lake Michigan. Total contaminant loads have decreased

since the 1970s, and atmospheric deposition has increased in importance over time because of decreases in direct discharges to the lake and

levels in sediments (Exhibit 2-11). 

The Integrated Atmospheric Deposition Network (IADN) and the Great

Lakes Fish Monitoring Program (GLFMP) monitor persistent bioaccumulative toxic (PBT) pollutants in the air and fish, respectively, of the

Great Lakes. Both programs show decreases in PBTs over time (Exhibits

2-12 and 2-13). In spite of these downward trends, levels of PCBs and

other PBTs in certain types of fish still exceed health protection levels in

all five lakes. Air data from Chicago showing elevated PCB levels suggest

that cities still contain significant sources of PCBs. 

GLFMP samples are also being used to identify the presence of “new”

bioaccumulating pollutants in the Great Lakes, such as certain brominated flame retardants.

Values in kilograms per year

19701995

Exhibit 2-11: Lake Michigan polychlorinated biphenyls 

(PCBs) sources, 1970 and 1995

12000

4500

1610

1150

2500

350

Tributaries Atmosphere Sediment

Note: This graphic was created for this report by the EPA Great Lakes National 

Program Office and the EPA, Office of Research and Development's Large Lakes 

Research Station using MICHTOX, a mass balance and bioaccumulation model, 

and air, water, and sediment data drawn from the Great Lakes Environmental 

Monitoring Database (GLENDA). The 1970 model run was based on available data 

and extrapolations. The 1995 model run was based on data collected during the 

Lake Michigan Mass Balance Study that collected over 25,000 samples at 200 

locations in 1994-1995.

Source: EPA, Great Lakes National Program Office. Great Lakes Environmental 

Monitoring Database (GLENDA). 2002. 

Total Atmospheric Inputs (Wet + Dry + Gaseous Absorption)

0

200

400

600

800

1000

1200

1400

1600

1800

1992 1993 1994 1995 1996 1997 1998

Year Total atmospheric inputs (kg/yr)

Total PCBs

DDT

Exhibit 2-12: Atmospheric deposition of PCBs and DDT 

in the Great Lakes, 1992–1998

Note: Note: R2 is the coefficient of determination. It gives a measure of the 

strength of the correlation.

Source: Buehler, S., et al. Atmospheric Deposition of Toxic Substances to the Great 

Lakes: IADN Results through 1998. 2001.

PCB Trend Line

R = 0.7476

DDT Trend Line

R2 = 0.6947

0

5

10

15

20

25

1972 1976 1980 1984 1988 1992 1996 2000 PCBs (parts per million) 

*Lake Trout (Walleye in Lake Erie)

Exhibit 2-13: Polychlorinated biphenyls (PCBs) 

 trends in Great Lakes fish tissue,* 1972–2000

Source: EPA, Great Lakes Fish Monitoring Program. Toxics in Top Predator Fish. 

February 24, 2003 (April 4, 2003; 

http://www.epa.gov/glnpo/glindicators/fishtoxics/topfishb.html). 

L. Michigan

L. Ontario

L. Huron

L. Erie

L. Superior
Chapter 2 - Purer Water

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EPA’s Draft Report on the Environment 2003

Consumption of Fish and Shellfish

Minnesota Chippewa Tribe: Fish Consumption

The Minnesota Chippewa are a federally recognized tribal confederation with approximately 40,000 members. The tribe’s six reservations occupy approximately 1.8 million acres in the northern portion of Minnesota, including 667 lakes covering approximately

700,000 acres, 702 miles of streams, and 250,000 acres of wetlands. Because water is an abundant natural resource for the tribe,

its members rely heavily on fish caught in those waters as a source of food.

The major, widespread contaminants in Minnesota Chippewa tribal waters are mercury, DDT, PCBs, and dioxin and furans. Fish consumption is the primary route of human exposure to these contaminants. Thus, the tribe chose as a primary environmental indicator

the quantity of fish from its waters that can be consumed safely by its most at-risk members: women of childbearing age, nursing

mothers, and children. 

The tribally designated, treaty-protected quantity of preferred fish consumption is 224 grams (about 8 ounces) per day. The quantity

of preferred fish that may be consumed safely by the most at-risk citizens is limited to 5 percent (about 0.4 ounces) or less of that 8

ounces.

Lake-specific guides for fish consumption are prepared for members of the tribe. The guides offer recommendations on the pounds per

month of several fish species that it is safe to consume.43

with pathogens associated with human or animal wastes can

cause gastrointestinal illness—even death in people with

compromised immune systems (see Chapter 4 – Human

Health). Mollusks, mussels, and whelks are the main shellfish

that can carry biotoxins causing common symptoms, such as

irritation of the eyes, nose, and throat as well as tingling lips

and tongue.44

Contaminated fish and shellfish are a particular concern to

people in either of two high-risk categories: those with conditions that put them more at risk (e.g., pregnant women,

nursing mothers, children, or people with compromised

immune systems); and people who consume fish as a primary

food source (e.g., some tribes and ethnic groups). Because of

their higher consumption rates, some communities have

developed their own guidance to identify specific types of

fish of concern (see box, “Minnesota Chippewa Tribe: Fish

Consumption”). 
Many sources of data support indicators that help to

answer questions about the condition of water and

watersheds, the quality of drinking water, the quality of water supporting recreation in and on the water, and

consumption of fish and shellfish—as well as the potential

stressors and effects associated with these. Other indicators

show potential stressors and associated effects, but the data

have limited ability to fully answer the questions.

Water and Watersheds

It is difficult to use existing

data to give a complete and

accurate picture of the state of U.S. surface waters to support

aquatic life for several reasons: 

■ Only a portion of waters is sampled to assess the condition

of the whole; many have targeted their monitoring programs to known problem areas.

■ States and tribes do not use a consistent set of monitoring

procedures for water quality.

■ Monitoring designs are not structured across agencies to

assess the condition of all U.S. waters. Sampling techniques, sampling locations, and even data analysis procedures are inconsistent. 

■ States define “quality” in different ways. The standards of

each state accommodate both the state’s policies and the

important physical and ecological differences that can exist

between waters.

The situation is similar for watersheds. Given existing data

and differing monitoring approaches, a comprehensive nationwide assessment of watershed condition has not been

achieved. More comprehensive and consistent monitoring is

needed, particularly when the changing face of the American

landscape is considered. Building dams and channels, withdrawing water for irrigation, and expanding development are

changing the shape and flow of streams, but there are insufficient data on the effects of those activities on aquatic habitats. There are, however, some very strong state and regional

programs that collect data on pollution loads and their

effects on aquatic habitats. The Chesapeake Bay Program’s

suite of indicators is an excellent example (see box,

“Chesapeake Bay Program Suite of Indicators”). 

Human Uses of Water

Resources

Similar problems occur in

gathering information on other water-related issues. For example, underreporting and late reporting of community water

system violations data by states to EPA continue to affect the

ability to report accurately on the quality of the nation’s

drinking water. Of the 49 states that issue fish advisories, six

do not use a risk-based approach. An EPA study of 268 contaminants in freshwater fish tissue is in the first of four seasons of monitoring, but cannot yet contribute to an

understanding of the national scope of this issue. The data

on beach closings and advisories include most coastal and

Great Lakes beaches but few inland beaches. Reporting is voluntary, and not all states report consistently. Similarly, data

on the effects of contamination on animals and plants are

lacking. Monitoring designs are not yet structured across

agencies to assess the condition of the entire country. 

2-21

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EPA’s Draft Report on the Environment 2003

Limitations of Water Indicators

Limitations of Water Indicators 
Chapter 2 - Purer Water

2-22

EPA’s Draft Report on the Environment 2003

Limitations of Water Indicators

Chesapeake Bay Program Suite of Indicators

EPA’s Chesapeake Bay Program uses indicators extensively for making decisions, informing the public about conditions and trends, and measuring

progress toward specific environmental goals. The indicators presented below were selected from more than 90 existing environmental management

measures. 

Maryland, Pennsylvania, Virginia, the District of Columbia, the Chesapeake Bay Commission, EPA (representing 21 federal agencies), participating

citizen groups, local governments, and scientific advisory groups are all involved in the development, peer review, and approval of the indicators and

goals.

Trends in Blue Crab: Mature Females

The number of mature female crabs is well below the long-term average

and has declined since the early 1990s. 

Acres of Bay Grasses

Acres of bay grasses increased to more than 85,000 acres in 2001 from

a low point of 38,000 acres in 1984. 

Water Clarity

As of 2001, most of the mainstem bay, larger embayments, and lower

regions of large tributaries meet the minimum light requirement for submerged aquatic vegetation; upper regions of large tributaries and many

minor tributaries do not. 

Nutrient Loads Delivered to the Bay

Between 1985 and 2000, nutrient loads to the bay decreased significantly: annual phosphorus loads decreased by 8 million pounds per year;

and annual nitrogen loads decreased by 51 million pounds per year

(Exhibit 2-14). 

Riparian Forest Buffer– Conservation and Restoration

Between 1996 and August 2002, 2,283 miles of riparian forest were

restored (Exhibit 2-15). 

Exhibit 2-15: Riparian forest buffer conservation and restoration, 1996–2002

Status of Bay Basin 

Streambanks and 

Shoreline: 1990s

Riparian Forest 

Buffer Restoration

Riparian Forest 

Buffers (59%) 1996 1997 1998 1999 2000 2001 2002 Cumulative Miles Restored

Year 2010 Goal: 

2,010 miles

2500

2000

1500

1000

500

0

Note: There are a total of 

approximately 199,000 miles of 

streambank and shoreline in the 

Bay watershed.

*Through August 2002.

Source: EPA, Chesapeake Bay Program. Chesapeake Bay Riparian Forest Buffer 

Inventory. September 1996; EPA Chesapeake Bay Program. Chesapeake Bay 

Program Office Data Center. June 1998; EPA Chesapeake Bay Program Office 

Forestry Workgroup. Riparian Forest Buffer Conservation and Restoration. 

January 2, 2003. (April 7, 2003; http://www. chesapeakebay.net/status/cfm?sid=83).

Phosphorus Nitrogen

19852000

0

50

100

150

200

250

300

350 Nitrogen Loads (millions of lbs/yr)

19852000

0

5

10

15

20

25 Phosphorus Loads (millions of lbs/yr) Note: Data include total nitrogen and phosphorus loads delivered to the Bay from point 

and nonpoint sources, from Chesapeake Bay Agreement jurisdictions: MD, PA, VA, and 

DC.

Source: EPA, Chesapeake Bay Program. Phase 4.3 Watershed Model. Last updated July 

2002.

Exhibit 2-14: Total nutrient loads delivered to the 

Chesapeake Bay from MD, PA, VA, and DC, 1985 and 2000 

Phosphorus Goal Nitrogen Goal
2-23

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EPA’s Draft Report on the Environment 2003

Endnotes

Endnotes

1 Alley, W.M., T.E. Reilly, and O.L. Franke. Sustainability of

Ground-water Resources, U.S. Geological Survey Circular

1186. Denver, CO, 1999.

2 U.S. Geological Survey. Strategic Directions for the U.S.

Geological Survey Ground-Water Resources Program: A Report to

Congress, Reston, VA, November 30, 1998. 

3 Ibid.

4 Alley, et al. Sustainability of Ground-Water Resources, 1999.

op. cit.

5 Indiana Department of Environmental Management. 2002

State of the Environment Report. 2002. (February 2003;

http://www.in.gov/idem/soe2002/water/surface.html).

6 U.S. Environmental Protection Agency. National Coastal

Condition Report, EPA 620-R-01-005. Washington, DC: U.S.

Environmental Protection Agency, Office of Research and

Development and Office of Water, September 2001.

7 U.S. Environmental Protection Agency. National Coastal

Condition Report, 2001. op. cit.

8 Ibid.

9 Ibid.

10 Dahl, T.E. Status and Trends of Wetlands in the Conterminous

United States 1986 to 1997, Washington, DC: U.S. Department

of the Interior, U.S. Fish and Wildlife Service, 2000.

11 Dahl, T.E. Wetland Losses in the United States 1780’s to

1980’s, Washington, DC: U.S. Department of the Interior, Fish

and Wildlife Service, 1990.

12 Dahl, T.E. Status and Trends of Wetlands of the Conterminous

United States 1986 to 1997, 2000. op. cit.

13 Rabalais, N.N., R.E. Turner, D. Justic, Q. Dortch, and W.J.

Wiseman, Jr. Characterization of Hypoxia: Topic 1 Report for the

Integrated Assessment on Hypoxia in the Gulf of Mexico, NOAA

Coastal Ocean Program Decision Analysis Series No. 15.

Silver Spring, MD: National Oceanic and Atmospheric

Administration, 1999.

14 Rabalais, N.N., Louisiana Universities Marine Consortium.

Unpublished data, personal communication. February 11,

2003.

15 U.S. Environmental Protection Agency. Sound Health 2001:

Status and Trends in the Health of Long Island Sound, Stamford,

CT: EPA Long Island Sound Office, 2001.

16 Ibid.

17 Office of the Governor of Louisiana, Wetlands

Conservation and Restoration Authority. Coastal Wetlands

Conservation and Restoration Plan, Fiscal Year 2002-2003.

2001. (February 14, 2003; http://www.goca.state.la.us/pdf/

StatePlan2002/FULLPLAN.PDF ).

18 Ibid.

19 U.S. Environmental Protection Agency, Office of Water.

National Section 303(d) List Fact Sheet. March 10, 2003.

(February 14, 2003; http://oaspub.epa.gov/waters/

national_rept.control).

20 Ibid.

21 The H. John Heinz III Center for Science, Economics and

the Environment. The State of the Nation’s Ecosystems:

Measuring the Lands, Waters, and Living Resources of the United

States, New York: Cambridge University Press, September

2002.

22 Bricker, S.B., C.G. Clement, D.E. Pirhalla, S.P. Orlando, and

D.R.G. Farrow. National Estuarine Eutrophication Assessment:

Effects of Nutrient Enrichment in the Nation’s Estuaries. Silver

Spring, MD: National Oceanic and Atmospheric

Administration, National Ocean Service, Special Projects
Chapter 2 - Purer Water

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EPA’s Draft Report on the Environment 2003

Office and the National Centers for Coastal Ocean Science,

1999.

23 The Heinz Center. The State of the Nation’s Ecosystems:

Measuring the Lands, Waters, and Living Resources of the United

States, 2002. op. cit.

24 U.S. Environmental Protection Agency. The Incidence and

Severity of Sediment Contamination in Surface Waters of the

United States, National Sediment Quality Survey, Second Edition,

DRAFT, EPA 823-R-01-01. Washington, DC: U.S. Environmental Protection Agency, Office of Water, December 2001.

25 Gilliom, R.J., D.K. Mueller, J.S. Zogorski, and S.J. Ryker. A

national look at water quality. Water Resources Impact 4:12-16

(2002).

26 U.S. Environmental Protection Agency. Summary of

Biological Assessment Programs and Biocriteria Development for

States, Tribes, Territories, and Interstate Commissions: Streams

and Wadeable Rivers, EPA 822-R-02-048. Washington, DC:

U.S. Environmental Protection Agency, Office of Environmental Information and Office of Water, December 2002.

27 U.S. Environmental Protection Agency. National Coastal

Condition Report, 2001. op. cit.

28 U.S. Environmental Protection Agency. Factoids: Drinking

Water and Ground Water Statistics for 2002, EPA 816-K-03-

001. Washington, DC: U.S. Environmental Protection Agency,

Office of Water, January 2003.

29 U.S. Environmental Protection Agency. Current Drinking

Water Standards, EPA 816-F-02-013. Washington, DC: U.S.

Environmental Protection Agency, Office of Water, July 2002.

30 Ibid.

31 Hoxie, N.J., J.P. Davis, J.M. Vergeront, R.D. Nashold, and K.A.

Blair. Cryptosporidiosis - associated mortality following a

massive waterborne outbreak in Milwaukee, WI. American

Journal of Public Health 87 (12): 2032-2035 (1997).

32 Ibid.

33 Craun, G.F. and R.L. Calderon. “Waterborne Outbreaks in

the United States, 1971-2000.” In Frederick W. Pontius (ed.),

Drinking Water Regulation and Health, New York, NY: John

Wiley & Sons, 2003, 40-56.

34 U.S. Environmental Protection Agency. National Health

Protection Survey of Beaches for the 2001 Swimming Season, EPA

823-F-02-008. Washington, DC: U.S. Environmental

Protection Agency, Office of Water, May 2002.

35 Ibid.

36 Ibid.

37 U.S. Environmental Protection Agency. Action Plan for

Beaches and Recreational Waters, EPA 600-R-98-079.

Washington, DC: U.S. Environmental Protection Agency,

Office of Research and Development and Office of Water,

March 1999.

38 U.S. Environmental Protection Agency. 2001 National

Listing of Fish and Wildlife Advisories, EPA 823-F-02-010.

Washington, DC: U.S. Environmental Protection Agency,

Office of Water, May 2002.

39 National Oceanic and Atmospheric Administration. The

1995 National Shellfish Register of Classified Growing Waters,

Silver Spring, MD: Office of Ocean Resources Conservation

and Assessment, Strategic Environmental Assessments

Division, 1997.

40 U.S. Environmental Protection Agency. 2001 National

Listing of Fish & Wildlife Advisories, 2002. op. cit.

41 U.S. Environmental Protection Agency. The Incidence and

Severity of Sediment Contamination in Surface Waters of the

United States, National Sediment Quality Survey, 2001. op. cit.

42 National Oceanic and Atmospheric Administration, U.S.

Environmental Protection Agency, et al., Marine Biotoxins and

Harmful Algae: A National Plan. 1993. (February 18, 2003;

http://www.redtide.whoi.edu/hab/nationplan/s-kplan/

s-kcontents.html).

43 White Earth Reservation Department of Natural Resources

and the Minnesota Chippewa Tribe Research Lab. White Earth

Reservation Fish Consumption Guide 2000, Ponsford and Cass

Lake, MN: White Earth Reservation Biology Department and

Minnesota Chippewa Tribe Research Lab, 2000.

44 Ibid.

Endnotes
3-1

Chapter 3 - 

Better Protected Land
Chapter 3 - Better Protected Land

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EPA’s Draft Report on the Environment 2003

Introduction

Introduction

T

he United States is a nation rich in land resources. The

land provides the foundation on which communities are

built, and from which food, shelter, and other essentials

are obtained. Vast acreages not only provide habitat for hundreds of thousands of species, but also support agricultural

activities, timber production, and mineral and energy extraction. In addition, diverse landscapes provide numerous opportunities for recreation and aesthetic enjoyment, including

hiking, bird watching, gardening, camping, and skiing. 

Much like air and water, land is a resource that must be carefully managed and protected. What happens on the land can

affect not only land itself, but air and water as well, with

potential consequences for human and

ecological health. Protecting land

resources means ensuring that lands

meet current needs and support healthy

communities and ecosystems. To this

end, EPA’s land protection activities focus

on the prevention, management, control,

and cleanup of various substances that

are released to or used on land, such as

toxic chemicals, pesticides, fertilizers, and wastes. Other government agencies, notably the U.S. Department of the

Interior and the U.S. Department of Agriculture (USDA) at

the federal level, manage land for natural resource and conservation purposes. Additionally, cities and counties adopt

and implement land use laws and regulations, overseen in

some cases by the states.

This chapter examines critical questions about aspects of

land use, chemical and waste applications, and land contamination: How much land is being used for various purposes?

How has this use changed over time? How much waste is

generated, how has this changed, and how is the waste managed or disposed of? What is the extent

of land contamination? The answers help

to set a baseline against which to measure the effects of land practices on the

condition of human health and ecosystems. The chapter presents available

national-level data on these questions,

and identifies gaps where the data are

limited. 

Chapter 3: Better Protected Land

Land Use

Chemicals in

the Landscape

Limitations of 

Land Indicators

Waste and

Contaminated Lands
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EPA’s Draft Report on the Environment 2003

Land Use

Land Use

T

he U.S. landscape has changed over the past 400 years

through extensive use in meeting human needs for food

and shelter, economic and energy development, and

recreation. Before European settlers came to this country, the

more than 2 billion acres of landscape consisted of forests,

grasslands, deserts, shrublands, and wetlands. Today, 98 million acres are considered developed lands supporting residential, commercial, industrial, and transportation uses; 377

million acres are used specifically to produce crops; and 832

million acres are considered grazing lands.1,2

The federal government manages nearly 28 percent of the

nation’s lands, or 630 million acres, mostly in the western

U.S. and Alaska.3 Federal management responsibilities are distributed among several agencies, including the USDA Forest

Service, the Bureau of Land Management, the National Park

Service, the U.S. Fish and Wildlife Service, and the U.S.

Department of Defense. State and local governments manage

another 198 million acres.4,5 The more than 828 million acres

of publicly managed lands support various public purposes,

such as recreational uses, the production of specific commodities, grazing for cattle and sheep, mineral exploration and

development, and timber harvesting.6,7,8 In many parts of the

country, public land provides highly valued open space. 

More than 4 percent of the

nation is designated as

wilderness, and millions of

other acres are protected in

national parks, state parks,

wildlife refuges, or other

classifications of reserved

land. Of the 106 million

acres of land now designated

as federal wilderness, more

than half are in Alaska.9 Such

protected lands provide

recreational opportunities,

open space, wildlife habitat,

and watershed protection. 

More than 1.4 billion acres of private and tribal land are managed in the interests of their owners, with various land use

constraints imposed by zoning and other regulations.10,11

Although both private and public landowners may use their

lands for similar purposes, such as harvesting timber and raising livestock, private lands are more likely to be developed

and used for crop production than those under public ownership. Many levels of government regulate land use, with widely

varying practices, creating challenges in understanding

national patterns of land use. 

Another important land use, but one for which it is not possible to identify how much land is used, is land managed for

energy production and other forms of mining. There are

almost 1,900 producing coal mines, the majority of them surface mines in western states and underground mines in

Appalachia. There are also nearly 2,000 other mines and

534,000 oil wells across the country. The extent of land that

those activities affect is not known, but some of the results of

mining are described in the chemicals and waste discussions

in this chapter.12

The following questions focus primarly on the extent of various land uses. Extent is important because it affects habitat

availability for all species, including humans. Extent of land

cover and land use represent two different concepts and both

are discussed. Land cover is essentially what can be seen on

the land—the vegetation or other physical characteristics—

while land use describes how a piece of land is being managed by humans. In some cases, land uses can be determined

by cover types (e.g., the presence of housing indicates residential land use), but often more information is needed for

those uses that are not visible (e.g., lands leased for mining,

“reserved” forest land, “grazing rights” on shrublands). Extent

of uses and cover types is additionally complicated because

there are numerous varying estimates of actual amounts due

to different terminology, definitions, and approaches to estimation. Within the discussion of each question, those variations are explored. The importance of extent is discussed in

more detail in Chapter 5 – Ecological Condition. 

Land Use Indicators

Extent of developed lands

Extent of urban and suburban

lands

Extent of agricultural land uses

Extent of grasslands and 

shrublands

Extent of forest area, ownership,

and management
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Land Use

What is the extent of developed

lands?

The majority of Americans live

in areas or transport themselves

on lands that are considered to

be “developed land.” Estimates

of the actual amount of developed land vary depending on definitions of “developed” and

differing assessment techniques.13 The USDA Natural

Resources Conservation Service’s National Resources

Inventory (NRI) estimated that there were approximately 98

million acres of developed land in the United States in 1997

(Exhibit 3-1).14 That represents 4.3 percent of the nation’s

total land area, up from 3.2 percent in 1982.15 Between 1982

and 1997, approximately 25 million acres of land, primarily

forest and cropland, were converted to developed uses. The

pace of land development in the 1990s was more than 1.5

times that of the 1980s.16 Since the middle of the last century, the number of Americans living in U.S. Census Bureaudefined urban areas increased from 64 percent to 79 percent

of the total population.17 Urban and suburban ecosystems

represent a subset of developed lands and include highly

urbanized areas and surrounding suburbs, and developed outlying areas greater than 270 acres in size. Estimates are that

there were approximately 32 million acres of urban and suburban lands in 1992.18

Exhibit 3-1: Extent of non-federal developed land, 1997 

Hawaii

98,251,700 acres of developed land

Metropolitan areas are defined as U.S. Census

Bureau Metropolitan Statistical Areas

Source: USDA, Natural Resources Conservation Service. National Resources Inventory, 1997, revised December 2000: Acres of Developed Land, 1997. 2000. 

(January 2003; http://www.nrcs.usda.gov/technical/land/meta/m4974.html

Puerto Rico/U.S. Virgin Islands

Red dot represents 15,000

acres of developed land

95% or more

federal area

Metropolitan area

boundaries

Metropolitan area

central cities

Alaska 
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Land Use

What is the extent of

farmlands?

Farmlands are lands used for growing crops and producing

forage, as well as the lands that contribute to those uses,

such as forested windbreaks or farmsteads. Currently, there

are no accurate estimates of the extent of farmland. Different

components of farmland can be identified, including approximately 377 million acres of non-federal lands that are used to

grow crops and 120 million acres of pastureland managed to

produce forage for livestock.19 Most of these croplands and

pasturelands are privately owned. Another 712 million acres

of both private and public lands may support grazing for livestock production, but these lands are not specifically seeded

or fertilized and are normally not considered part of farmlands.20,21 Lands used for agricultural production show constant shifts in the uses among crop, pasture, range, and forest

to meet production needs, implement rotations of land in and

out of cultivation, and maintain and sustain soil resources.

Within those shifts, however, trends indicate that the amount

of cropland, rangeland, and pastureland in the U.S. has gradually decreased because of lower U.S. exports of grain, improvements in agricultural productivity and efficiency, and

conversion of agricultural lands to development near growing

population centers.22 Between 1982 and 1997, cropland

acreage decreased by 10.4 percent (44 million acre decrease)

and pastureland acreage by 9.1 percent (12 million acre

decrease) (Exhibit 3-2).23 In that same timeframe, however,

32.7 million acres consisting primarily of croplands were

enrolled in the Conservation Reserve Program (CRP), a voluntary program that encourages farmers to set aside agricultural

lands for conservation purposes.24

What is the extent of grasslands

and shrublands?

As of 1992, the ecosystem of grasslands and shrublands

occupied about 861 million acres in the lower 48 states and

205 million acres in Alaska, for a total of 1.066 billion acres

(excluding Hawaii), or about 47 percent of the U.S.25 That

area includes not only the grasslands and shrublands of the

West but coastal meadows, grasslands and shrubs in Florida,

mountain meadows, hot and cold deserts, and tundra. It also

includes more-managed grasslands and agricultural lands that

are often classified as rangelands and pasturelands. One of

the challenges in determining the extent of this ecosystem is

that grasslands and shrublands can be used for grazing and

are often counted as agricultural lands.

The State of the Nation’s Ecosystems: Measuring the Lands,

Waters, and Living Resources of the United States concludes that

no consistent, nationwide data are available on the change in

acreage of grasslands and shrublands. Researchers have estimated that there were between 900 million and 1 billion

acres of grasslands and shrublands in the lower 48 states

before European settlement. On the basis of that estimate,

between 40 million and 140 million acres had been converted

to other uses by 1992.26

What is the extent of forest

lands?

In 2001, forests covered about

one-third of the national land

area, approximately 749 million

acres.27, 28 It is estimated that in

1630, 1.045 billion acres of

forest land existed in what was to become the land area of

the U.S. Nearly 25 percent of these lands were cleared by the

early 1900s, leaving 759 million acres of forest land in 1907.

Since that time the total amount of forest land nationwide,

Exhibit 3-2: Change in cropland, CRP land, and 

pastureland acreage, 1982–1997

Decrease = 23 million acres Millions of acres

0

100

200

300

400

500

600

1982 1987 1992 1997

Pastureland

Conservation Reserve Program

Cropland

Source: USDA, National Resources Conservation Service. Summary Report 1997 

National Resources Inventory (revised December 2000). 2000.
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Land Use

while changing regionally has remained relatively stable, with

an increase of 2 million acres between 1997 and 1999.29

Most forested lands are managed for a combination of uses,

including recreation, timber production, grazing, and mining.

Approximately 10 percent of the nation’s forests is “reserved”

through designations such as national parks or wilderness

areas, and 9 percent supports private industrial (major timber

management companies) timber production.30 In 2001, the

USDA Forest Service considered more than 503 million acres

of both private and public forests “timberlands,” or available

for harvest. From 1976 to 2001, public land harvest nationwide dropped nearly 47 percent to less than 2 billion cubic

feet annually. In the same timeframe, private land harvest

increased by almost 29 percent to 14 billion cubic feet annually (Exhibit 3-3).31 Private forests are being converted to

developed land uses faster than any other land type.32

(Chapter 5 – Ecological Condition contains a more detailed

discussion of forest land condition.)

What human health effects are

associated with land use?

Land development patterns have direct effects on air and

water quality, which can then affect human health. The

increased concentration of air pollutants in developed areas

can exacerbate human health problems such as asthma.

Increased storm water runoff from impervious surfaces can

increase the flow of polluted runoff into surrounding waterbodies that residents may rely on for drinking and recreation.

Development patterns can affect quality of life by limiting

recreational opportunities, decreasing open space and wildlife

habitat, and increasing vehicle miles traveled and the amount

of time spent on roads. And, as discussed later in this chapter, agricultural land uses may expose humans to dust and

various chemicals. 

What ecological effects are

associated with land use?

Land use and land management practices change the landscape in many ways that can have direct and indirect—as well

as positive and negative—ecological effects. One direct

effect is the conversion of one type of use to a more humanoriented land use, such as developed land or agriculture.

Examples of indirect effects may include changes in runoff

patterns or soil erosion. 

Land development affects water quality and quantity by creating hard surfaces such as roads, structures, and parking

lots. Such impervious surfaces limit the natural soil filtering

process, change runoff patterns, contribute to floods, and

potentially contribute to the effects of droughts due to lower

water tables. Land development also creates “heat islands,”

domes of warmer air over urban and suburban areas caused

by the loss of the cooling effects of trees and shrubs and the

absorption of more heat by pavement, buildings, and other

sources. Some agricultural practices can degrade ecological

condition, such as livestock grazing, which can damage

streamside vegetation and contribute nutrients to ecosystems

that then enter waterbodies. Forest practices can affect water

quality when trees are removed along streams or on steep

slopes, causing erosion, stream sedimentation, increased

water temperatures (from loss of shade), and loss of fish

habitat. Tree planting can have positive ecological effects by

lowering stream temperatures and improving fish habitat.

Other chapters contain further discussion of the effects of

land development and agricultural and forest uses on ecosystems and water quality (see Chapter 2 – Purer Water; and

Chapter 5 – Ecological Condition). 

Land use can also have indirect effects on air quality. Patterns

of dispersed land development increase the number of miles

Exhibit 3-3: Timber removals in the United States 

by owner group, 1952–2001 Billion cubic feet

Total Public

Total Private

0

5

10

15

20

1952 1962 1976 1986 1996 2001

Source: USDA, Forest Service. Draft Resource Planning Act Assessment Tables. 

May 3, 2002 (updated August 12, 2002). (September 2003; http:// 

www.ncrs.fs.fed.us/4801/FIADB/rpa_tabler/Draft_RPA_2002_Forest_Resource_Tables.pdf).
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Land Use

driven by commuters. Agricultural land uses contribute to

wind erosion and dust in many areas of the country.

Certain land uses and practices, such as land conversion,

overgrazing, excess fertilization, and use of agricultural chemicals, can enhance the growth of invasive plants.35

Additionally, failure to manage invasive species can lead to

major threats to native ecosystems.36

Land practices related to development, timber harvest, and

agriculture can affect soil quality both positively and negatively. Some agricultural practices such as organic farming,

creation of buffer strips in riparian areas, and precision pesticide and fertilizer application technologies can improve land

conditions. Other practices may negatively affect soil quality

by promoting soil compaction and erosion. Soil erosion can

have several major effects on ecosystems. Sediment is the

greatest pollutant in aquatic ecosystems, by both mass and

volume, and soil erosion and transport are the source.37

Although rates of erosion declined between 1982 and 1997

by about 1.4 tons per acre, more than one-quarter of all

croplands still suffer excessive water and wind erosion.38,39

(Excessive is defined as exceeding “tolerable” rates as defined

by USDA Natural Resources Conservation Service models).40

Land conversion and land management practices also have

significant effects on sensitive areas, such as wetlands, coastal

areas, and the banks of streams, rivers, and lakes. According

to USDA estimates, most wetland conversion over the past 15

years, particularly in the southern and eastern parts of the

country, has been due to land development.41 (See Chapter 2

– Purer Water for an in-depth discussion of wetlands, their

significance, and loss.)

Measuring Impervious Surfaces

One effect of land development is the creation of impervious surfaces—areas, for example, with pavement or buildings, which restrict

or prevent the infiltration of water into underlying soil. Research has shown that increasing the amount of impervious surfaces within

watersheds can degrade streams and affect the health of aquatic ecosystems. Some aquatic species may be affected when impervious

surfaces constitute as little as 2 percent of a watershed’s area; others may be affected when impervious surface area is 10 to 12 percent. By preventing the processing of pollutants through soils, impervious surfaces help channel pollutants directly into waterways.

Estimates of impervious areas have been developed based on many approaches, including the use of remotely sensed satellite imagery

such as the National Land Cover Dataset (NLCD), assessments of population and road density, and zoning delineations. Over the

last several years, EPA researchers analyzed 1,624 watersheds in Georgia using two different approaches. In the first approach, three

different data sets (population density from census block-level data, commercial/industrial and quarrying/mining land cover categories

from the NLCD, and major highway and interstate digital data coverage) were integrated for analysis. The second approach applied

assumptions about percentage of imperviousness to various classes of NLCD data. The NLCD-only approach showed that 69 of the

Georgia watersheds had greater than 10 percent total impervious area, while the integrated analysis identified 80. The NLCD-only

approach identified 76 watersheds in the 5 to 10 percent impervious range, whereas the integrated analysis showed 117 watersheds.

The results indicate that the NLCD-only approach provides a rapid-assessment tool for identifying currently urbanized and impaired

watersheds (more than 10 percent imperviousness), but it underestimates potentially vulnerable watersheds that may suffer impairment in the near future (currently 5 to 10 percent imperviousness).33,34
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Chemicals in the Landscape

Chemicals in the Landscape

How much and what types of

toxic substances are released

into the environment?

Many industries release toxic

substances into the air, soil,

and water through their manufacturing and production

activities. Under the

Emergency Planning and Community Right-to-Know Act of

1986 and the Pollution Prevention Act of 1990, facilities are

required to calculate and report to EPA and states their

releases of more than 650 toxic chemicals and chemical compounds. EPA makes these toxics release data available to the

public through the Toxics Release Inventory (TRI). In 2000,

total TRI releases reached 7 billion pounds. Of these releases,

58 percent were to land, 27 percent were to air, 4 percent

each were to water and underground injection at the generating facility, and 7 percent were chemicals disposed of off-site

to land or underground injection. Between 1998 and 2000,

toxic releases decreased overall by about 409 million pounds,

or 5.5 percent. Of that total, releases to land decreased by

approximately 276 million pounds (Exhibit 3-4).43 Of the

original set of chemicals from industries that have reported

consistently since 1988, total on- and off-site releases

decreased 48 percent between 1988 and 2000, a reduction

of 1.55 billion pounds.44

Some of the releases reported in the TRI include chemicals

that are managed under EPA regulations. For example, the

above figures for total releases in the TRI include chemicals in

waste disposed of in hazardous waste disposal units regulated

under Subtitle C of the Resource Conservation and Recovery

Act (RCRA), whether at the generating facility or after being

transferred to another facility. Approximately 206 million

pounds of toxic chemicals in waste were disposed of in RCRA

Subtitle C facilities in 2000, which corresponds to approximately 2.9 percent of total TRI releases in 2000.45 In addiT

he nation’s commerce depends greatly upon the development and use of chemical products, and over the past

50 years, the use of such chemicals has increased significantly. The Toxic Substances Control Act chemical inventory

now identifies more than 76,000 chemicals currently or

recently used in the country. Nearly 10,000 of those, excluding inorganic polymers, microorganisms, naturally occurring

substances, and non-isolated intermediaries, are produced or

imported in quantities greater than 10,000 pounds per year;

for about 3,100 chemicals, the quantities exceed 1 million

pounds per year. Associated annual production and import

volumes increased by 570 billion pounds (9.3 percent) to

6.7 trillion pounds between 1990 and 1998.42 Commercial

and industrial processes such as mining, manufacturing, and

electrical generation all use and release chemicals. Pesticides

are used in homes, yards, factories, and office buildings and,

most frequently, to support agricultural production, where

they have contributed to an increase in agricultural productivity levels over the past 50 years. Fertilizers, used to supplement soils for enhanced plant growth, have also contributed

to those productivity increases.

The use and release to the

environment of chemicals

have created a range of challenges for protecting human

health and the environment.

Toxic chemicals, including

some pesticides, can lead to

a variety of acute or chronic

health problems, and excess

fertilizers carried in runoff

may contribute nutrients to

aquatic ecosystems that

harm water quality and

aquatic life. 

Chemicals in the

Landscape

Indicators

Quantity and type of toxic

substances released and managed

Agricultural pesticide use

Fertilizer use

Pesticide residues in food

Potential pesticide runoff from farm

fields

Risk of nitrogen export

Risk of phosphorous export
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Chemicals in the Landscape

tion to the 7 billion pounds of toxic chemicals released in

2000, 31 billion pounds of toxic chemicals were managed

and transferred for treatment (50 percent), recycling (39

percent), and burning for energy recovery (11 percent). The

total amount of toxic chemicals managed and transferred

between 1998 and 2000 increased by almost 29 percent, a

net increase of 8.4 billion pounds.46 For the past few years,

EPA has tracked three metals—lead, mercury, and cadmium—

and 27 organic chemicals, which were identified as the highest priorities for waste minimization. The Agency uses those

waste minimization priority chemicals (WMPC) to measure

the total weight of particularly toxic chemicals going to disposal. Trend data are available for 17 of the 30 WMPCs and

show that releases of those 17 have been steadily declining

since 1993 (Exhibit 3-5). Overall, between 1991 and 1998,

there was a 44 percent reduction in WMPC quantities generated in industrial and hazardous waste.47

Persistent bioaccumulative toxic (PBT) chemicals, including

dioxins, lead, mercury, and PCBs, are tracked because they

persist and accumulate in the environment. In 2000, PBTs

represented 12.1 million pounds (less than 1 percent) of the

released chemicals that TRI tracks.48 Although they constitute a fraction of overall toxic releases, PBTs are significant

even in small quantities, given the chronic risks they pose to

ecosystems and humans through bioaccumulation. 

What are the volume,

distribution, and extent of

pesticide and fertilizer use?

Pesticides are substances or mixtures used to destroy or repel

various pests, including insects, animals, plants, and microorganisms. EPA’s most recent Pesticide Industry Sales and Usage

report shows that annual use of pesticides for all purposes

Exhibit 3-4: Total Toxics Release Inventory (TRI) releases 

across industry, 1998−2000 Billions of pounds

Total Air Emissions

Surface Water Discharges

Underground Injection

On-Site Land Releases

Transfers Off-Site to Disposal

0

2

4

6

8

1998 1999 2000

Source: EPA, Office of Environmental Information. 2000 Toxics Release Inventory 

(TRI) Public Data Release Report. May 2002. Exhibit 3-5: Trends in Toxics Release Inventory (TRI) waste 

minimization priority chemicals (WMPC), 1991–1998 Million pounds 50

0

100

150

200

1991 1993 1995 1997 1998

0%

+1%

-28%

-36%

-44%

Source: EPA, Office of Solid Waste and Emergency Response. Waste Minimization 

Trends Report (1991-1998). September 2002.
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Chemicals in the Landscape

declined by about 15 percent between 1980 and 1999.49

This decline has not been steady, with pesticide use higher in

1999 than it was in the early 1990s. Excluding chlorine

used for disinfection, the largest use of pesticides is in agricultural production, and that use fluctuates, depending on a

number of factors such as weather or type of crop. According

to the National Center for Food and Agricultural Policy

(NCFAP), a private, non-profit research organization, use of

agricultural pesticides increased between 1992 and 1997

from 892 million to 985 million pounds.50 The recent EPA

report shows a similar increase in use of all pesticides in this

same timeframe, with a leveling of use between 1997 and

1999.51

Approximately half of those pesticides are herbicides used to

control weeds that limit or inhibit the growth of a desired

crop. Pesticides are also used in smaller quantities in rightsof-way, businesses, and home lawns and gardens. Based on

EPA’s national pesticide sales estimates, industrial, commercial, and governmental pesticide applications—many of which

occur in urban environments—totaled 148 million pounds in

1999. Home and garden pesticide use was estimated to be

140 million pounds.52

The use of insecticides, which as a class tend to be the pesticides most acutely toxic to humans and wildlife, significantly

declined between 1997 and 2001. The number of individual

chemical treatments per acre (acre-treatments) for insecticides labeled “danger for humans” decreased by 43 percent.

In that same period, acre-treatments for insecticides labeled

“extremely or highly toxic to birds” declined by 50 percent,

and acre-treatments of those labeled “extremely or highly

toxic to aquatic organisms” dropped by 23 percent.53

The use of nitrogen, phosphorus, and potash, the most

prevalent fertilizer supplements in commercial farming,

rose from 7.5 million nutrient

tons (tons of a chemical nutrient in a fertilizer mixture) in

1961 to nearly 24 million nutrient tons in 1981. Exhibit 3-6

displays trends in the use of fertilizer over the past 40 years.

Although aggregate use dipped in 1983, it increased most

recently between 1996 and 1998 to more than 22 million

nutrient tons.54 Use of most major fertilizers is concentrated

on croplands in the Midwest.55 (Chapter 2 – Purer Water discusses some of the effects of fertilizer use on water quality.)

What is the potential

disposition of chemicals from

land?

Chemicals and nutrients can move from their location of use

or origin to a place in the environment where humans and

other organisms can become exposed to them. People are

exposed to chemicals in all aspects of their daily lives,

through their clothing, use of everyday products, housing,

automobiles, and buildings.

Pesticide residues on food are one way people can be

exposed to pesticides. The U.S. Department of Agriculture's

Pesticide Data Program (PDP) measures pesticide residue levels in fruits, vegetables, grains, meat, and dairy products from

across the country, sampling different combinations of commodities each year. In 2000, PDP collected and analyzed a

total of 10,907 samples: 8,912 fruits and vegetables, 178

rice, 716 peanut butter, and 1,101 poultry which originated

from 38 States and 21 foreign countries. Approximately 80 Millions of nutrient tons

Total

Nitrogen

Phosphorus

Potash

0

5

10

15

20

25

19601965197019751980198519901995

Exhibit 3-6: Use of fertilizer, 1960–1998

Source: Daberkow, S. et al. Agricultural Resources and Environmental Indicators: 

Nutrient Use and Management. February 2003.
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Chemicals in the Landscape

percent of all samples were domestic, 19 percent were

imported, and less than 1 percent was of unknown origin.56

The simple presence of detectable pesticide residues in foods

should not be considered indicative of a potential health concern. The PDP uses analytical methods that are very sensitive

and are capable of detecting extremely small (or “trace”)

quantities of pesticides that are orders of magnitude lower

than those raising potential health concerns. Overall, approximately 42 percent of all samples contained no detectable

pesticide residues, 22 percent contained a detectable residue

of a single pesticide, and 35 percent contained detectable

amounts of two or more pesticides. Testing found that no

more than 1.4 percent of samples exceeded regulatory limits

(also known as “tolerance levels”). Residues exceeding the

pesticide tolerance level established by EPA for that food

were detected in only 0.2 percent of all composite samples.

Residues of other pesticides for which no tolerance level had

been set by EPA for that food were found in 1.2 percent of

all samples. These residues were generally at low concentrations and may be due to spray drift, crop rotations, or cross

contamination at packing facilities. USDA reports all such

exceedances to the Food and Drug Administration for further

investigation and any needed follow-up.57

Pesticide and fertilizer runoff into surface and ground water

can also expose humans and the environment to the effects

of chemicals. Models that use data from the USDA NRI, the

NCFAP, and other sources show that the highest potential for

pesticide runoff is predominantly associated with the upper

and lower Mississippi and Ohio River valleys.58 Similarly, EPA

has developed models based

on land cover characteristics to

assess the risk of nitrogen and

phosphorus runoff into watersheds. Those studies also show

that the areas with the highest

risk for nitrogen and phosphorus runoff are concentrated in

the midwestern states and

other agricultural areas.59 (See

Chapter 5 – Ecological

Condition for additional discussion of how nutrient runoff

can affect the chemical characteristics of ecosystems.)

In addition to runoff, chemicals can enter land through pesticide “spray drift,” the physical movement of a pesticide

through air at the time of application, or soon thereafter, to

any site other than that intended for application. Both modeling and incident reports indicate that spray drift is a route

of disposition.60

What human health effects are

associated with pesticides,

fertilizers, and toxic

substances?

Because they are designed to kill or harm living organisms,

many pesticides pose some risk to humans, animals, and the

environment. The risk of adverse health effects depends on

how, where, how much, and how frequently pesticides are

used; what happens after use; who is exposed; and how they

are exposed. Human exposures to harmful levels of chemicals,

such as organophosphates or organochlorine pesticides, can

cause adverse neurological, developmental, and reproductive

effects. A significant challenge lies, however, in correlating the

existence of chemicals in the environment, either singly or in

combination, with the health effects observed in a given population.

There are no nationwide pesticide surveillance systems to

track exposure consistently, but several state and national

pesticide surveillance systems do collect information on pesticide-related injuries and illness. Although those systems are

not nationally comprehensive,

their information provides a

starting point for examining the

health effects of pesticides. 

Fertilizers are often applied in

greater quantities than crops

can absorb and end up in surface or ground water. Although

fertilizers may not be inherently

harmful, they can be linked to

human health problems when

excess nutrients cause algal

blooms and eutrophication in

waterbodies. Drinking ground

water contaminated with runoff
Chapter 3 - Better Protected Land

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Chemicals in the Landscape

from some fertilizers can have severe or even fatal health

effects, especially in infants and children (e.g., blue baby syndrome).61

The Toxic Exposure Surveillance System (TESS) contains

information from poison control centers that report

occurences of pesticide-related injury and illness. One finding

from TESS data is that organophosphates are much more likely to cause post application symptoms than are other types

of pesticides. In addition, the data show that in 2001, more

than 100,000 people were sufficiently concerned about their

actual exposure to pesticides to call their local poison control

center. Estimates are that approximately 19 percent of the

people who called developed symptoms as a result of their

pesticide exposure. These symptoms included abdominal

pain, diarrhea, vomiting, rash, blurred vision, irriatation to

eyes or skin, headache, dizziness, coughing, and difficulty

breathing. In addition, of the approximately 20,000 cases

that were followed to determine medical outcome: 83 percent

had a minor outcome, 15 percent had a moderate outcome

(usually require treatment), and 1.5 percent had a major outcome (life-threating symptoms or residual disability).62 Other

studies of treated poisonings, not just from pesticides, have

found that the poison control center data may capture only

about 25 percent of all poisoning incidents.63 

Health effects from exposure to toxic chemicals range from

short-term acute effects to long-term chronic effects such as

cancer or asbestosis. For example, as discussed in Chapter 4

– Human Health, despite major success in reducing exposure

to lead, many children remain at risk of neurological damage

through lead poisoning—primarily from contact with leadbased paint chips and lead-containing dust in their homes. In

addition, EPA, along with other state and federal agencies

that are responsible for protecting public health, pays special

attention to PBTs and persistent organic pollutants, which do

not easily break down and thus tend to accumulate in humans

and other organisms. Such accumulation can lead to serious

chronic health issues.64

What ecological effects are

associated with pesticides,

fertilizers, and toxic

substances?

A number of ecological effects of direct chemical exposure on

individual species have been identified. Reproductive failure in

birds, for example, has been linked to organochlorine insecticides such as DDT, which are still present in the environment

from past applications in the United States, as well as from

current use in other parts of the world. Many pesticides are

toxic to a variety of fish, bird, plant, and insect species. As a

result, use—and especially misuse—of pesticides can, where

exposures are of sufficient magnitude, cause significant loss

of non-target species. Eliminating or limiting those exposures

may have a beneficial effect. For example, the resurgence of

the bald eagle population is thought to be the result, at least

in part, of bans on various chemicals.65

Indirect environmental effects of pesticides and other chemicals on ecosystems are more complex and difficult to understand. As previously discussed, pesticides and nutrients run

off from their point of application and are deposited in

aquatic systems and sediments, where they may accumulate

to levels that exceed water quality standards for specific

chemicals. (The effects of runoff on the condition of aquatic

systems are discussed in more detail in Chapter 2 – Purer

Water.)
3-13

Chapter 3 - Better Protected Land

EPA’s Draft Report on the Environment 2003

Chemicals in the Landscape

Contaminant Levels and Bald Eagles in Michigan

Bald eagles were significantly affected by contaminants in the environment in the early 1960s and 1970s. Now monitoring them can provide a gross indication of general contaminant levels in the environment. In 1999, a consortium

of the Michigan Department of Environmental Quality, the U.S. Fish and Wildlife Service, and researchers from

Michigan State University and Clemson University initiated a bald eagle contaminant-monitoring project. Ninety

samples of blood and feathers were collected by non-lethal procedures from permanent inland nests, from nests in

additional inland watersheds being assessed as part of the Michigan department’s 5-year watershed assessment

cycle, and from Great Lakes and connecting channel nests. 

Exhibits 3-7 and 3-8 show changes in mean PCB levels and mean mercury levels, respectively, in bald eagles between

the late 1980s and early 1990s, and in 1999. Specifically, PCB levels in the blood of bald eagles were dramatically

lower in 1999 for inland nests and those in Lakes Superior, Michigan, and Huron. (Although Lake Erie did not show the same result, only one eagle

was sampled there in 1999.) Similarly, mean mercury levels in bald eagle feathers declined in all geographic areas examined.

The Michigan Department of National Resources has also conducted an annual census of bald eagle nests in Michigan since 1961. The nests

increased from 50 in 1961 to 366 in 2000. During that same time period, bald eagle productivity, as measured by the number of young fledged per

nest, increased more than 50 percent.

The contaminant and population measures demonstrate that levels of key environmental contaminants in bald eagles within the Great Lakes Region

have declined through the 1990s, and that populations and productivity are increasing.66

Exhibit 3-7: Mean polychlorinated biphenyls (PCB) concentrations in nesting bald eagle feathers, 

1987–1992 and 1999

0

50

100

150

200

250

Lake 

Superior

Lake 

Michigan

Lake 

Huron

Lake 

Erie

Interior 

Lower

Peninsula

Interior 

Upper 

Peninsula

1987–1992 1999 Mean PCB Concentration (microgram/kilogram) Source: Michigan Department of Environmental Quality, Office of Special 

Environmental Projects. State of Michigan's Environment 2001: First Biennial Report. 

2001.

0

2

3

4

5

6

7

8

9

10

Interior Lower 

Peninsula

Interior Upper 

Peninsula

Lake Superior Lakes Michigan 

and Huron

1985–1989 1999

Exhibit 3-8: Mean mercury levels in 

nesting bald eagle feathers, 

1985–1989 and 1999 Mean Mercury (microgram per liter) Source: Michigan Department of Environmental Quality, Office of Special 

Environmental Projects. State of Michigan's Environment 2001: First Biennial Report. 

2001.
Chapter 3 - Better Protected Land

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EPA’s Draft Report on the Environment 2003

Waste and Contaminated Lands

“Waste” is broadly defined as unwanted material

left over from manufacturing processes or refuse

from places of human or animal habitation.

Within that category are many types of waste, including

municipal solid waste, hazardous waste, and radioactive waste,

which have properties that may make them dangerous or

capable of having a harmful effect on human health and the

environment.67 Waste and contaminated lands are particularly

important to environmental health because they may expose

land and living organisms to harmful material if they are not

properly managed. 

There have been major improvements in managing the

nation’s waste and in cleaning up contaminated sites.

National, state, tribal, and local waste programs and policies

aim to prevent pollution by reducing the generation of wastes

at their source and by emphasizing prevention over management and subsequent disposal. Preventing pollution

before it is generated and

poses harm is often less

costly than cleanup and

remediation. Source reduction and recycling programs

often can increase resource

and energy efficiencies and

thereby reduce pressures on

the environment. When

wastes are generated, EPA,

state environmental programs, and local municipalities work to reduce the risk

of exposures. If land is contaminated, cleanup programs

address the sites to prevent

human exposure and ground

water contamination.

Increased recycling protects land resources and extends the

life span of disposal facilities.

How much and what types of

waste are generated and

managed?

The types of waste generated range from yard clippings to

highly concentrated hazardous waste. Only three types of

waste—municipal solid waste (MSW), hazardous waste (as

defined by the Resource Conservation and Recovery Act

[RCRA]), and radioactive waste—are tracked with any consistency on a national basis. Other types of waste, for which no

or very limited national data exist, are listed in the box,

“Other Types of Waste,” and are described in detail in

Appendix B.

MSW, commonly known as trash or garbage, is one of the

nation’s most prevalent waste types. In 2000, the U.S. generated approximately 232 million tons of MSW, primarily in

homes and workplaces—an increase of nearly 160 percent

since 1960.68 During that time, the population increased 56

percent, and gross domestic product increased nearly 300

percent.69 In 2000, each person generated approximately

4.5 pounds of waste per day—or about 0.8 tons for the

year—a per-capita generation increase from 2.7 pounds per

day in 1960.70 For the last decade, per capita generation has

remained relatively constant, and the amount of MSW recovered (recycled or composted) increased more than 1,100

percent, from 5.6 million to 69.9 million tons in total (Exhibit

3-9).71 Combustion (incineration) is also used to reduce the

volume of waste before disposal. Approximately 33.7 million

tons (14.5 percent) of MSW were combusted in 2000.72 Of

that amount, approximately 2.3 million tons were combusted

for energy recovery—a process where energy is produced

from waste combustion and made available for other uses.73

Waste and

Contaminated

Lands Indicators

Quantity of municipal solid waste

(MSW) generated and managed

Quantity of RCRA hazardous waste

generated and managed

Quantity of radioactive waste

generated and in inventory

Number and location of municipal

solid waste (MSW) landfills

Number of RCRA hazardous waste

management facilities

Number and location of Superfund

national priority list sites

Number and location of RCRA

corrective action sites

Waste and Contaminated Lands 
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Chapter 3 - Better Protected Land

EPA’s Draft Report on the Environment 2003

Waste and Contaminated Lands

The term “RCRA hazardous waste” applies to hazardous waste

(waste that is ignitable, corrosive, reactive, or toxic) that is

regulated under the RCRA. In 1999, EPA estimated that

20,000 businesses generating large quantities—more than 2,200 pounds each per

month—of hazardous waste collectively

generated 40 million tons of RCRA hazardous waste.74 Comparisons of annual

trends in hazardous waste generation are difficult because of changes in the types of

data collected (e.g., exclusion of wastewater)

over the past several years. But the amount

of a specific set of priority toxic chemicals

found in hazardous waste and tracked in the

Toxics Release Inventory is declining, as previously discussed under “Chemicals in the

Landscape.” In 1999, approximately 69 percent of the RCRA hazardous waste was disposed of on land by one of four disposal methods: deep

well/underground injection, landfill disposal, surface

impoundment, or land treatment/application/farming.75

In 2000, approximately 600,000 cubic meters of different

types of radioactive waste were generated, and approximately

700,000 cubic meters were in storage awaiting disposal.76 By

volume, the most prevalent types of radioactive waste are

contaminated environmental media (i.e., soil, sediment, water,

and sludge requiring cleanup or further assessment) and lowlevel waste. Both of these waste types typically have the lowest levels of radioactivity when measured by volume.

Additional radioactive wastes in the form of spent nuclear fuel

(2,467 metric tons of heavy metal) and high-level waste

“glass logs” (1,201 canisters of vitrified high-level waste) are

in storage awaiting long-term disposal.77 Very small amounts

of those wastes are still being generated. For example, less

than 1 cubic meter of spent nuclear fuel was generated in

2000. The total amount of radioactive waste being generated

is expected to drop over the next few decades as cleanup

operations are completed.78

As previously mentioned, other types of waste for which

national data are not available or are not current are listed

below and described in Appendix B. These other types of

waste contribute a substantial amount to the

total waste “universe,” although the exact

percentage of the total that they represent is

unknown. 

What is the extent of

land used for waste

management?

Between 1989 and 2000, the number of

municipal landfills in the U.S. decreased substantially—from 8,000 to 2,216.79 The combined capacity of all landfills, however,

Exhibit 3-9: Municipal solid waste management, 

1960–2000 Millions of tons *Composting of yard trimmings and food wastes. Does not include mixed MSW 

composting or backyard composting. 

Source: EPA, Office of Solid Waste and Emergency Response. Municipal Solid Waste 

in the United States: 2000 Facts and Figures. June 2002.

0

50

100

150

200

250

1960 1965 1970 1975 1980 1985 1990 1995 2000

Recovery for Composting*

Recovery for Recycling

Combustion

Landfill

(2000 total = 232 million tons)

Other Types of Waste

Extraction wastes

Industrial non-hazardous waste

Household hazardous waste

Agricultural waste

Construction and demolition waste

Medical waste

Oil and gas waste

Sludge
Chapter 3 - Better Protected Land

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EPA’s Draft Report on the Environment 2003

Waste and Contaminated Lands

remained relatively constant because newer landfills typically

have larger capacities. In 2000, municipal landfills received

approximately 128 million pounds of MSW, or about 55 percent of what was generated.80 In addition to municipal landfills, the nation had 18,000 surface impoundments—ponds

used to treat, store, or dispose of liquid waste—for non-hazardous industrial waste in 2000.81

Excluding wastewater, nearly 70 percent of the RCRA hazardous waste generated in 1999 was disposed of at one of

the nation’s RCRA treatment, storage, and land disposal facilities. Of the 1,575 RCRA facilities, 1,049 are storage-only

facilities. The remaining facilities perform one or more of several common management methods (e.g., deepwell/underground injection, metals recovery, incineration, landfill

disposal).82

The nation also uses other sites for waste management and

disposal, but there are no comprehensive data sets that

assess those additional sites or the extent of land now used

nationally for waste management in general. Before the

1970s, waste was not subjected to today’s legal requirements

to reduce toxicity before disposal and was typically disposed

of in open pits. Early land disposal units that still pose

threats to human health and the environment are considered

to be contaminated lands and are subject to federal or state

cleanup efforts. 

What is the extent of

contaminated lands?

Many of the contaminated sites that must be managed and

cleaned up today are the result of historical contamination.

Located throughout the country, contaminated sites vary

tremendously. Some sites involve small, non-toxic spills or

single leaking tanks, whereas others involve large acreages of

potential contamination such as abandoned mine sites. To

address the contamination, federal and state programs use a

variety of laws and regulations to initiate, implement, and

enforce cleanup. The contaminated sites are generally classified according to applicable program authorities, such as

RCRA Corrective Action, Superfund, and state cleanup programs. 

Note: "Construction Complete" sites include most "Deleted" sites and some "Final" sites. 

Source: EPA, Office of Solid Waste and Emergency Response. National Priorities List Site Totals by Status and Milestone. March 26, 2003. (April 3, 2003; 

http://www.epa.gov/superfund/sites/query/queryhtm/npltotal.htm) and Number of NPL Site Actions and Milestones by Fiscal Year. March 26, 2003. (April 3, 2003; 

http://www.epa.gov/superfund/sites/query/queryhtm/nplfy/htm

Exhibit 3-10. Superfund National Priorities List (NPL) site totals by status and milestone, 1990–2002 Number of sites

300

600

900

1200

1500

1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002

Deleted Sites

Final Sites

Proposed Sites

Construction Complete
3-17

Chapter 3 - Better Protected Land

EPA’s Draft Report on the Environment 2003

Waste and Contaminated Lands

Although many states have data about

contaminated sites within their boundaries,

the total extent of contaminated land in

the U.S. is unknown because few data are

aggregated for the nation as a whole and

acreage estimates are generally not available. A nationally accurate assessment

would require both more detailed information on specific sites—such as the area of

each site—and consistent aggregation of

those data nationally. To assess the full

nature of “extent” would require data on

specific contaminants, as well as an assessment of risks, hazards, and potential for

exposure to those contaminants.

The most toxic abandoned waste sites in the nation are listed

on the Superfund National Priorities List (NPL) (Exhibit

3-10). Thus, examining the NPL data—along with data on

RCRA corrective action sites—provides an indication of the

extent of the most significantly contaminated sites. NPL sites

are located in every state and several territories. As of

October 2002, there were 1,498 final or deleted NPL sites.83

An additional 62 sites were proposed to the NPL.84 (When a

“proposed” site meets the qualifications to be cleaned up

under the Superfund Program, it becomes a final NPL site.

Sites are considered for “deletion” from the NPL list when

cleanup is complete.) Of the 1,498 sites, 846 sites are “construction completion sites,” which are former toxic waste sites

where physical construction for all cleanup actions are complete, all immediate threats have been addressed, and all longterm threats are under control. This is up from 149

construction completes in l992.

EPA also estimates that approximately 3,700 hazardous waste

management sites may be subject to RCRA corrective action,

which would provide for investigation and cleanup and remediation of releases of hazardous waste and constituents.

Contamination at the sites ranges from small spills that

require soil cleanup to extensive contamination of soil, sediment, and ground water. In addition, 1,714 of these 3,700

potential corrective action sites are high-priority sites that are

targeted for immediate action by federal,

state, and local agencies.85

Other types of contaminated lands, for

which data are very limited, include areas

contaminated by leaking underground storage tanks and brownfields. Brownfields are

lands on which hazardous substances, pollutants, or contaminants may be or have

been present. Brownfields are often found

in and around economically depressed

neighborhoods. Cleaning up and redeveloping these lands can benefit surrounding

communities by reducing health and environmental risks, creating more functional

space, and improving economic conditions.

The other types of contaminated lands are listed here (see

box) and described in more detail in Appendix B. 

What human health effects are

associated with waste management and contaminated lands?

People who live, work, or are otherwise near contaminated

lands and waste management areas are more vulnerable than

Other Types of

Contaminated Lands

Leaking underground storage tanks 

Accidental spill sites

Land contaminated with radioactive and

other hazardous materials

Brownfields

Some military bases

Waste management sites that were poorly

designed or poorly managed

Illegal dumping sites

Abandoned mine lands
Chapter 3 - Better Protected Land

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EPA’s Draft Report on the Environment 2003

Human Exposures Under Control at Identified Contaminated Sites

Progress is being made to control the pathways by which humans are potentially exposed, under current conditions, to unacceptable levels of contaminants

at Superfund and priority RCRA Corrective Action sites. In October 2002, 1,199 Superfund sites out of 1,494 Superfund sites were found to have

human exposures under control (Exhibit 3-11a).86 As of March 2003, 1,056 of 1,714 RCRA Corrective Action sites were similarly found to have human

exposures under control (Exhibit 3-11b).87 “Under control” indicates that EPA or state officials have determined that there are no unacceptable human

exposures to contamination (present above appropriate risk-based levels) that can be reasonably expected under current land- and water-use conditions.

Examples of risk-based levels used in these determinations include EPA- and/or varying state-promulgated standards, as well as other appropriate standards, guidelines, guidance, or criteria.

Government officials base a “Current Human Exposures Under Control” determination on site-specific characterization information, including chemical

analyses of relevant environmental media (ground water, surface water, indoor and outdoor air, and soil), and on the potential ways people could be

exposed to that contamination including inhalation, direct contact, or ingestion of the contaminated media or food impacted by contaminated media. In

addition, examples of exposure control actions taken that could lead to an “under control” determination include implementing cleanups such as removing

contaminated media, providing alternative water supplies, and implementing access and other land use controls and restrictions. These site-specific evaluations result in an EPA or state official determining that human exposures are either under control, not under control, or that there is insufficient information

to make the determination.

It is important to note that the environmental measurements, human activity patterns, and actions taken to prevent exposure are the basis of these human

exposures determinations. Biomonitoring or personal monitoring (see Chapter 4 – Human Health) is not typically used to make these determinations.

Furthermore, EPA uses “Current Human Exposures Under Control” as a means to measure short-term protectiveness; additional cleanup actions (i.e.,

beyond those on which the “Current Human Exposures Under Control” is based) may be necessary as part of a final remedy designed to ensure long-term

protection from reasonably expected future exposures.

a. Human exposure under control at Superfund National Priorities List 

(NPL) hazardous waste sites

Source: EPA, Office of Solid Waste and Emergency Response. Comprehensive 

Environmental Response, Compensation, and Liability Information System 

(CERCLIS) Database. October 2002.

Note: The data used in this display were drawn directly from the CERCLIS 

database specifically for this report using queries for human exposure. 

4 deleted/deferred NPL sites are not included.

12% 

Insufficient 

Data

1,494 sites total

8%

Not Under

Control

80%

Under

Control

1,199

175

120

b. Human exposure under control at Resource Conservation and 

Recovery Act (RCRA) Corrective Action hazardous waste sites

Source: EPA, Office of Solid Waste and Emergency Response. Facilities on the 

RCRA GPRA Cleanup Baseline. March 2003.

Note: The data used in this display were drawn from the RCRAInfo database 

using code CA 725 (Human Exposures Controlled). The results displayed for 

insufficient data include those facilities that have yet to be evaluated for this 

determination.

1,714 sites total 8%

Not Under

Control

62%

Under

Control

Exhibit 3-11: Human exposure under control at identified hazardous waste sites

30%

Insufficient

Data

1,056

140 518

Waste and Contaminated Lands
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Chapter 3 - Better Protected Land

EPA’s Draft Report on the Environment 2003

Waste and Contaminated Lands

Migration of Contaminated Ground Water Under Control 

at Identified Contaminated Sites

Progress is being made to control the spread of contamination in ground water at Superfund and priority RCRA Corrective Action sites. As of

October 2002, 772 out of 1,275 Superfund sites had ground water contamination under control (Exhibit 3-12a).88 Similarly, as of March

2003, 899 of the 1,714 RCRA Corrective Action sites were under control (Exhibit 3-12b).89 “Under control” means a plume of contaminated

ground water is not spreading above appropriate risk-based levels, or is not adversely affecting surface water bodies into which contaminated

ground water is discharging. Examples of risk-based levels used in these determinations include EPA- and/or varying state-promulgated standards,

as well as other appropriate standards, guidelines, guidance, or criteria. 

Government officials base a “Migration of Contaminated Ground Water Under Control” determination on site-specific characterization information

and monitoring data pertaining to relevant environmental media (e.g., ground water and surface water where warranted). In addition, examples of

actions taken that could lead to an “under control” determination include documenting the lack of plume growth in response to an engineered

“pump and treat” or subsurface barrier system, or in response to natural attenuation processes (both of which would include ongoing monitoring).

These site-specific evaluations result in an EPA or state official determining that the migration of contaminated ground water is under control, not

under control, or that there is insufficient information to make the determination.

EPA is using the “Migration of Contaminated Ground Water Under Control” determination as a means of protecting ground water and surface

water resources. As such, actual or potential human exposures to contaminants in ground water would be addressed in the “Current Human

Exposures Under Control” determination. Furthermore, “Migration of Contaminated Ground Water Under Control” is a short-term cleanup goal;

additional cleanup actions (i.e., beyond those on which this measure is based) may be necessary as part of a final remedy designed to ensure longterm protection of ground water resources.

Exhibit 3-12: Contaminated ground water migration under control at identified hazardous waste sites

a. Contaminated ground water migration under control at Superfund 

National Priorities List (NPL) hazardous waste sites

Source: EPA, Office of Solid Waste and Emergency Response. Comprehensive 

Environmental Response, Compensation, and Liability Information System 

(CERCLIS) Database. October 2002.

Note: The data used in this display were drawn directly from the CERCLIS 

database specifically for this report using queries for ground water migration.

17% 

Insufficient 

Data

1,275 sites total

23%

Not Under

Control

60%

Under

Control

772

212

291

b. Contaminated ground water migration under control at 

Resource Conservation and Recovery Act (RCRA) Corrective Action hazardous waste sites

Source: EPA, Office of Solid Waste and Emergency Response. Facilities on the 

RCRA GPRA Cleanup Baseline. March 2003.

Note: The data used in this display were drawn from the RCRAInfo database 

using code CA 750 (Migration of Contaminated Groundwater Controlled). 

The results displayed for insufficient data include those facilities that have 

yet to be evaluated for this determination. 

1,714 sites total

13%

Not Under

Control 53%

Under

Control

899

34% 

Insufficient 

Data

587

228
Chapter 3 - Better Protected Land

3-20

EPA’s Draft Report on the Environment 2003

others to the threats such areas might pose in the event of

accident or unintended exposure to hazardous materials.

Depending on factors such as management practices, the

sources of contamination, and potential exposure, some

waste, contaminated lands, and lands used for waste management pose a much greater risk to human health than others.

Some areas, such as properly designed and managed waste

management facilities, pose minimal risks. 

Determining the relationship between types of sites and

human health is usually extremely complicated. For many

types of cancer, understanding is limited by science and the

fact that people usually are exposed to many possible cancercausing substances throughout their lives. Isolating the contributions of exposure to contaminants to incidence of

respiratory illness, cancer, and birth defects is extremely difficult—impossible in many cases. Nonetheless, it is important

to gain a more concrete understanding of how the hazardous

materials associated with waste and contaminated lands affect

human populations. 

Although some types of potential contaminants and waste are

not generally hazardous to humans, other types can pose

dangers to health if people are exposed. The number of substances that exist that can or do affect human health is

unknown; however, the TRI program requires reporting of

more than 650 chemicals and chemical categories that are

known to be toxic to humans. 

EPA’s Superfund Program has identified several sources of

common contaminants, including commercial solvents, drycleaning agents, and chemicals. With chronic exposure, commercial solvents such as benzene may suppress bone marrow

function, causing blood changes. Dry-cleaning agents and

degreasers contain trichloroethane and trichloroethylene,

which can cause fatigue, depression of the central nervous

system, kidney changes (e.g., swelling, anemia), and liver

changes (e.g., enlargement).90 Chemicals used in commercial

and industrial manufacturing processes, such as arsenic,

beryllium, cadmium, chromium, lead, and mercury, may cause

various health problems. Long-term exposure to lead may

cause permanent kidney and brain damage. Cadmium can

cause kidney and lung disease. Chromium, beryllium, arsenic,

and cadmium have been implicated as human carcinogens.91 

What ecological effects are

associated with waste management and contaminated lands?

Hazardous substances, whether present in waste, on lands

used for waste management, or on contaminated land, can

harm wildlife (e.g., cause major reproductive complications),

destroy vegetation, contaminate air and water, and limit the

ability of an ecosystem to survive. For example, if not properly

managed, toxic residues left from mining operations can be

blown into nearby areas, affecting resident bird populations

and the water on which they depend. Certain hazardous substances also have the potential to explode or cause fires,

threatening both wildlife and human populations.92

The negative effects of land contamination and occasionally

of waste management on ecosystems occur after contaminants have been released on land (soil/sediment) or into the

air or water. For example, mining activities have affected

aquatic life in Colorado’s Eagle River, as described in box,

“Cleanup of the Eagle Mine Superfund Site.” 

Waste and Contaminated Lands
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Chapter 3 - Better Protected Land

EPA’s Draft Report on the Environment 2003

Cleanup of the Eagle Mine Superfund Site

The Eagle Mine, southwest of Vail, Colorado, was used to mine gold, silver, lead, zinc, and copper between 1870 and 1984. After the mine closed, several contaminants, including lead, zinc, cadmium, arsenic, and manganese, were left behind, and they spread into nearby ground water, the Eagle River,

and the air, posing a risk to people and wildlife.

Colorado filed notice and claim in 1985 against the former mine owners for natural resource damages under Superfund. In June 1986, the site was

placed on the National Priority List, and shortly thereafter the state and the previous owners agreed to a plan of action. Cleanup operations included

constructing a water treatment plant to collect mine seepage and other contaminated water sources; relocating all processed mine wastes and contaminated soils to one main, on-site tailings pile; capping that pile with a multilayer clean soil cap; and revegetating all disturbed areas with native plant

species. 

The water quality in the Eagle River began to show improvements in 1991; as zinc concentrations in the river dropped, the resident brown trout population grew (Exhibit 3-13). An October 2000 site review concluded that public health risks had been removed and that significant progress had been

made in restoring the Eagle River. Today, biological monitoring is undertaken to sample the Eagle River’s water quality, aquatic insects, and fish populations.93

Exhibit 3-13: Eagle mine zinc concentrations and brown trout populations downstream of the consolidated tailings pile Dissolved Zinc milligrams per liter (m/l) Number of Fish Per Acre

0.0

0.4

0.8

1.2

1.6

2.0

2.4

2.8

3.2

3.6

100

200

300

400

500

Sep 89 Sep 91 Sep 93 Sep 95 Sep 97 Sep 99 Sep 01

Note: Zinc concentrations fluctuate during the seasons according to water levels.

Source: Colorado Department of Public Health and Environment, Hazardous Materials and Waste Management Division. Eagle Mine. February 5, 2003. (April 7, 2003; 

http://www.cdphe.state.co.us/hm/rpeagle.asp#SiteSummary).

Zinc, 13-B (mg/l)

Fish per acre

Linear (Fish)

Waste and Contaminated Lands
advanced system for full pesticide use reporting. Reports

about the specifics of pesticide applications are filed by farmers, commercial applicators, structural pest control companies, and commercial landscaping firms.94

The TRI program does not cover all releases of chemicals

from all industrial facilities. For example, facilities that do not

meet the TRI reporting requirements (those that have fewer

than 10 full-time employees or do not meet TRI chemicalspecific threshold amounts for reporting) are not required to

report their releases. Some facilities conduct and report on

actual monitoring data; others use estimation approaches,

which are not consistent nationwide. New chemicals are being

produced constantly, which poses challenges to EPA’s efforts

to monitor their potential interaction and effects. 

Better information is needed on the chemistry, quantities, and

longevity of various substances; on the cumulative effects of

various chemicals on the environment and humans; and on

the pathways and effects of exposure. More monitoring is

required, along with more effective means to link ambient

exposures to health and ecological effects. A more comprehensive and cohesive intergovernmental—federal, state, and

local—reporting system that helps to link environmental and

health data would be of great assistance.

Waste and

Contaminated Lands

The data available nationally

on total waste generated are not comprehensive; they exist as

independent data sets maintained by different agencies and

organizations. The data are gathered in various units (e.g.,

MSW in weight by pounds or tons, radioactive waste in volume by canisters). No easy method exists to convert weight

to volume for understanding “extent.” 

Some data are available on sites used for various types of

waste management, but there is no broad assessment or

Many sources of data support indicators that help to

answer questions about the trends and effects of

land use, chemicals in the landscape, and waste

and contaminated land. But there are limitations in using the

indicators to fully answer the questions.

Land Use

There are a number of gaps in

information about land use

and cover. Significantly varying estimates of developed land

result from varying definitions and approaches to land use

assessments. Statistical sampling and satellite remote sensing

techniques vary in total estimates—and represent different

sources of error. Data on some cover types and land uses are

sparse or nonexistent, and inventories are seldom done on

lands in Alaska. Numerous federal agencies conduct national

inventories, but because they cover different land areas with

different classifications and varying statistical sampling, integrating those data is challenging. Remotely sensed data are

being used increasingly to estimate land cover but will probably need to be combined with other data sets to produce an

accurate estimate of land uses. Additionally, remote sensing

data from multiple years are not readily available for analysis

of trends. Soil erosion information is collected by the NRI for

croplands but does not exist nationally for forests or rangelands, particularly those under federal ownership.

Chemicals in the

Landscape

No pesticide reporting system

currently provides information on the volume, distribution,

and extent of pesticide use nationwide across all sectors.

Data used in this report are only estimates based on available

information that includes crop profiles, pesticide sales, expert

surveys, and sampling of stream and ground water. While no

national reporting system exists, California has developed an

Chapter 3 - Better Protected Land

3-22

EPA’s Draft Report on the Environment 2003

Limitations of Land Indicators

Limitations of Land Indicators
3-23

Chapter 3 - Better Protected Land

EPA’s Draft Report on the Environment 2003

national database of contaminated lands. National-level statistics on the total acreage of those lands, actual concentrations found in soils or waters around the sites, or health or

ecological effects around the sites do not exist. Lack of those

data creates challenges for addressing cleanup or redevelopment opportunities.

In lieu of national-level environmental indicators, activity

measures of prevention, reduction of toxicity, and cleanup are

used as indicators. Those measures take into account health

and ecological outcomes. At this time, they are the best available indicators of environmental status and effects.

4 Ibid.

5 Alaska Department of Natural Resources. Fact Sheet: Land

Ownership in Alaska. March 2000. (September 2002;

http://www.dnr.state.ak.us/mlw/factsht/land_own.pdf).

6 Ibid. 

7 U.S. Department of Agriculture, Natural Resources Conservation Service. America’s Private Land: A Geography of Hope,

Washington, DC: U.S. Department of Agriculture, June 1997.

8 U.S. General Services Administration. Summary report on real

property owned by the United States throughout the world, 1999.

op. cit.

9 Wilderness Information Network. National wilderness

preservation system database. August 2002. (February 10,

2003; http://www.wilderness.net/nwps).

Endnotes

Endnotes

1 U.S. Department of Agriculture, Natural Resources Conservation Service. Summary Report: 1997 National Resources

Inventory (Revised December 2000), Washington, DC: Natural

Resources Conservation Service and Ames, Iowa: Iowa State

University, Statistical Laboratory, December 1999, Revised

December 2000.

2 U.S. Department of the Interior. Rangeland Reform ‘94, Draft

Environmental Impact Statement, Washington, DC: Bureau of

Land Management, 1994.

3 U.S. General Services Administration. “Summary report on

real property owned by the United States throughout the

world.” 1999. In Statistical Abstract of the United States 2001:

The National Data Book. Washington, DC: U.S. Census Bureau

2001.
Chapter 3 - Better Protected Land

3-24

EPA’s Draft Report on the Environment 2003

Endnotes

10 U.S. Department of Agriculture. America’s Private Land: A

Geography of Hope, 1997. op. cit.

11 Alaska Department of Natural Resources. Fact Sheet: Land

Ownership in Alaska, 2000. op. cit.

12 U.S. Department of Energy, Energy Information

Administration. United States Country Analysis Brief.

November 2002. (January 2003;

http://www.eia.doe.gov/emeu/cabs/usa.html).

13 The H. John Heinz III Center for Science, Economics and

the Environment. The State of the Nation’s Ecosystems:

Measuring the Lands, Waters, and Living Resources of the United

States, New York, NY: Cambridge University Press, September

2002.

14 U.S. Department of Agriculture, Natural Resources

Conservation Service. 1997 National Resources Inventory

Highlights. January 2001. (February 2003;

http://www.nrcs.usda.gov/technical/land/pubs/97highlights.pdf).

15 Ibid.

16 U.S. Department of Agriculture, Natural Resources

Conservation Service. Summary Report: 1997 National

Resources Inventory (Revised December 2000), 2000. op. cit.

17 U.S. Census Bureau. Statistical Abstract of the United States

2001: The National Data Book, Washington, DC. 2001.

18 The Heinz Center. The State of the Nation’s Ecosystems:

Measuring the Lands, Waters, and Living Resources of the United

States, 2002. op. cit.

19 U.S. Department of Agriculture, Natural Resources

Conservation Service. Summary Report: 1997 National

Resources Inventory (Revised December 2000), 2000. op. cit.

20 The Heinz Center. The State of the Nation’s Ecosystems:

Measuring the Lands, Waters, and Living Resources of the United

States, 2002. op. cit.

21 U.S. Department of Interior. Rangeland Reform ‘94, Draft

Environmental Impact Statement, 1994. op. cit.

22 Vesterby, M., “Agricultural resources and environmental

indicators: land use.” In Agricultural Resources and

Environmental Indicators Report, Ag Handbook No. AH722.

Washington, DC: U.S. Department of Agriculture, Economic

Research Service, February 2003, 1-33.

23 U.S. Department of Agriculture. Summary Report: 1997

National Resources Inventory (Revised December 2000), 2000.

op. cit.

24 Ibid.

25 The Heinz Center. The State of the Nation’s Ecosystems:

Measuring the Lands, Waters, and Living Resources of the United

States, 2002. op. cit.

26 Klopatek, J.M., R.J. Olson, C.J. Emerson, and J.L. Jones. Landuse conflicts with natural vegetation in the United States.

Environmental Conservation 6: 191–199 (1979).

27 U.S. Department of Agriculture Forest Service. U.S. Forest

Facts and Historical Trends, Brochure #FS-696. Washington,

DC: U.S. Department of Agriculture, April 2001.

28 U.S. Department of Agriculture, Forest Service, Draft

Resource Planning Act Assessment tables. August 12, 2002.

(September 2002; http://www.ncrs.fs.fed.us/4801/FIADB/

rpa_tabler/Draft_RPA_2002_Forest_Resource_Tables.pdf).

29 Ibid.
3-25

Chapter 3 - Better Protected Land

EPA’s Draft Report on the Environment 2003

30 Ibid.

31 Ibid.

32 U.S. Department of Agriculture. National Resources

Inventory: Highlights, 2001. op. cit.

33 Bird, S., J. Harrison, L. Exum, S. Alberty, and C. Perkins.

“Screening to identify and prevent urban storm water problems: estimating impervious area accurately and inexpensively.” In Proceedings of the National Water Quality Monitoring

Council Conference, Madison, WI, May 19-23, 2002.

34 Bird, S.L., L.R. Exum, and S.W. Alberty. Generating high

quality impervious cover data. Quality Assurance 8: 91-103

(2001).

35 Westbrooks, R. Invasive Plants, Changing the Landscape of

America: Fact Book. Washington, DC: Federal Interagency

Committee for the Management of Noxious and Exotic

Weeds, 1998.

36 U.S. Fish and Wildlife Service. Invasive species

encroachment is one of the biggest threats to native

ecosystems that resource managers face today. No date

available. (August 2002; http://invasives.fws.gov/Index7.html).

37 U.S. Environmental Protection Agency. 2000 National

Water Quality Inventory, EPA 841-R-02-001. Washington DC:

U.S. Environmental Protection Agency, Office of Water, August

2002.

38 U.S. Department of Agriculture, Natural Resources

Conservation Service. State of the Land Index of Analysis

Products: Change in Average Annual Soil Erosion by Water on

Cropland and CRP Land, 1982-1997. 2000. (January 2003;

http://www.nrcs.usda.gov/technical/land/meta/m5060.html).

39 U.S. Department of Agriculture, Natural Resources

Conservation Service. State of the Land Index of Analysis

Products: Total Wind and Water Erosion, 1997. 2000.

(January 2003;

http://www.nrcs.usda.gov/technical/land/meta/m5083.html)

40 Ibid

41 U.S. Department of Agriculture, Natural Resources

Conservation Service. Summary Report: 1997 National

Resources Inventory (Revised December 2000), 2000. op. cit.

42 U.S. Environmental Protection Agency. Toxic Substances

Control Act Chemical Substance Inventory, Washington, DC: U.S.

Environmental Protection Agency, Office of Prevention,

Pesticides, and Toxic Substances, 2002.

43 U.S. Environmental Protection Agency. 2000 Toxics Release

Inventory Public Data Release Report, EPA 260-S-02-001.

Washington, DC: U.S. Environmental Protection Agency,

Office of Environmental Information, May 2002.

44 Ibid

45 Ibid

46 Ibid

47 Ibid

48 Ibid

49 U.S. Environmental Protection Agency. Pesticide Industry

Sales and Usage 1998 and 1999 Market Estimates. Washington,

DC: U.S. Environmental Protection Agency, Office of

Prevention, Pesticides, and Toxic Substances, September

2001.

Endnotes
Chapter 3 - Better Protected Land

3-26

EPA’s Draft Report on the Environment 2003

50 Gianessi, L.P., and M.B. Marcelli. Pesticide Use in U.S. Crop

Production: 1997, National Summary Report, Washington, DC:

National Center for Food and Agricultural Policy, November

2000.

51 U.S. Environmental Protection Agency. Pesticide Industry

Sales and Usage 1998 and 1999 Market Estimates. 2001.

op. cit.

52 Ibid.

53 U.S. Environmental Protection Agency, Office of Pesticide

Programs. Biopesticides registration action document: Bacillus

thuringiensis plant-incorporated protectants. October 16,

2001. (January 2003;

http://www.epa.gov/pesticides/biopesticides/pips/bt_brad.htm).

54Daberkow, S., H. Taylor, and W. Huang. “Agricultural

Resources and Environmental Indicators: Nutrient Use and

Management.” September, 2000. In Agricultural Resources

and Environmental Indicators, Agricultural Handbook No.

AH722. U.S. Department of Agriculture, Economic Research

Service, Washington, DC, February 2003, 4.4.1-4.4.49.

55 Vesterby, M. Agricultural resources and environmental indicators: land use, 2003. op. cit. 

56 U.S. Department of Agriculture. Pesticide Data Program:

Annual Summary Calendar Year 2000, Washington, DC: U.S.

Department of Agriculture, Agricultural Marketing Service,

2002.

57 Ibid.

58 U.S. Environmental Protection Agency, Office of Wetlands,

Oceans, and Watersheds. Pesticide Runoff Potential—1990-

1995. August 24, 1999.

59 Wickham, J.D., K.H. Ritters, R.V. O’Neill, K.H. Reckhow, T.G.

Wade, and K.B. Jones. Land Cover as a Framework for

Assessing Risk of Water Pollution. Journal of the American

Water Resources Association 36 (6); 1-6 (2000).

60 U.S. Environmental Protection Agency, Office of Pesticide

Programs. Spray Drift of Pesticides. December 1999.

(September 2002;

http://www.epa.gov/pesticides/citizens/spraydrift.htm).

61 M.O. Amdur, J. Doull and C.D. Klassen (eds.). Toxicology: the

Basic Science of Poisons, NY: Pergamon Press. 1996, 1033. 

62 Litovitz, T.L., W. Klein-Schwartz, G.C. Rodgers, D.J.

Cobaugh, J. Youniss, J.C. Omslaer, M.E. May, A.D.Woolf, and

B.E. Benson. 2001 annual report of the American Association

of Poison Control Centers: toxic exposure surveillance system.

American Journal of Emergency Medicine 20: 391-452, 2002.

63 National Environmental Education and Training Foundation.

National Strategies for Health Care Providers: Pesticides Initiative,

Washington, DC. 2002.

64 U.S. Environmental Protection Agency. Waste Minimization

Trends Report (1991-1998), EPA 530-R-02-007. Washington,

DC: U.S. Environmental Protection Agency, Office of Solid

Waste and Emergency Response, September 2002

65 U.S. Fish and Wildlife Service. Recovery Program: Endangered

and Threatened Species, Washington, DC: U.S. Fish and Wildlife

Service. 1994.

66 Michigan Department of Environmental Quality. State of

Michigan’s Environment 2001, First Biennial Report, Lansing, MI:

Office of Special Environmental Projects, 2001.

Endnotes
3-27

Chapter 3 - Better Protected Land

EPA’s Draft Report on the Environment 2003

67 U.S. Environmental Protection Agency. RCRA Orientation

Manual, EPA 530-R-0-006. Washington, DC: Office of Solid

Waste and Emergency Response, June 2000.

68 U.S. Environmental Protection Agency. Municipal Solid

Waste in the United States: 2000 Facts and Figures, EPA 530-S02-001. Washington, DC: U.S. Environmental Protection

Agency, Office of Solid Waste and Emergency Response, June

2002.

69 U.S. Department of Commerce, Bureau of Economic

Analysis. GDP and Other Major NIPA Series, 1929-2002.

2002. (February 2003; http://www.bea.doc.gov/bea/

ARTICLES/2002/08August/0802GDP_&Other_Major_

NIPAs.pdf).

70 U.S. Environmental Protection Agency. Municipal Solid

Waste in the United States: 2000 Facts and Figures, 2002. op.

cit. 

71 Ibid.

72 Ibid.

73 Ibid.

74 U.S. Environmental Protection Agency. The National Biennial

RCRA Hazardous Waste Report, EPA 530-R-01-009.

Washington, DC: U.S. Environmental Protection Agency,

Office of Solid Waste and Emergency Response, June 2001.

75 Ibid.

76 U.S. Department of Energy, Office of Environmental

Management. Central Internet Database. 2002. (January

2002; http://cid.em.doe.gov).

77 Ibid.

78 Ibid.

79 Goldstein, N. 12th Annual Biocycle Nationwide Survey: The

State of Garbage in America, Biocycle Journal of Composting and

Organics Recycling 41 (4); 30-40 (April 2000).

80 U.S. Environmental Protection Agency. Municipal Solid

Waste in the United States: 2000 Facts and Figures, 2002. op.

cit.

81 U.S. Environmental Protection Agency. Industrial Surface

Impoundments in the United States, EPA 530-R-01-005.

Washington, DC: U.S. Environmental Protection Agency,

Office of Solid Waste and Emergency Response, March 2001.

82 U.S. Environmental Protection Agency. The National Biennial

RCRA Hazardous Waste Report, 2001. op. cit.

83 U.S. Environmental Protection Agency, Superfund Emergency

Response Program. National Priorities List Site Totals by Status

and Milestone. February 6, 2003. (February 25, 2003;

http://epa.gov/superfund/sites/query/queryhtm/npltotal.htm).

84 Ibid.

85 U.S. Environmental Protection Agency, Office of Solid Waste

and Emergency Response. Corrective Action Background.

October 8, 2002. (October 15, 2002;

http://www.epa.gov/epaoswer/hazwaste/ca/backgnd.htm#5).

86 U.S. Environmental Protection Agency, Office of Solid

Waste and Emergency Response. Comprehensive

Environmental Response, Compensation, and Liability

Information System (CERCLIS) Database. October 16, 2002.

(May 8, 2003; http://cfpub.epa.gov/supercpad/cursites/

srchsites.cfm).

Endnotes
Chapter 3 - Better Protected Land

3-28

EPA’s Draft Report on the Environment 2003

87 U.S. Environmental Protection Agency, Office of Solid

Waste and Emergency Response. Facilities on the RCRA GPRA

Cleanup Baseline. March 3, 2003. (May 19, 2003;

http://www.epa.gov/epaoswer/hazwaste/ca/lists/base_fac.pdf).

88 U.S. Environmental Protection Agency, Office of Solid

Waste and Emergency Reponse. Comprehensive Environmental

Response, Compensation, and Liability Information System 

(CERCLIS) Database, 2002. op.cit.

89 U.S. Environmental Protection Agency, Office of Solid

Waste and Emergency Response. Facilities on the RCRA GPRA

Cleanup Baseline, 2003. op. cit.

90 U.S. Environmental Protection Agency, Superfund

Emergency Response Program. Sources of Common

Contaminants and Their Health Effects. September 20, 2002.

(February 25, 2003; http://www.epa.gov/superfund/

programs/er/hazsubs/sources.htm).

91 Ibid.

92 U.S. Environmental Protection Agency, Superfund

Emergency Response Program. Exposure pathways. No date.

(September, 2002; http://www.epa.gov/superfund/

programs/er/hazsubs/pathways.htm.).

93 Colorado Department of Public Health and Environment,

Hazardous Materials and Waste Management Division, Eagle

Mine. February 5, 2003. (September 2002;

http://www.cdphe.state.co.us/hm/rpeagle.asp#SiteSummary).

94 California Department of Pesticide Regulation. Pesticide

Use Reporting: An Overview of California's Unique Full Reporting

System, Sacramento, California: California Department of

Pesticide Regulation, May, 2000. (March 12, 2003;

http://www.cdpr.ca.gov/docs/pur/purovrvw/tabofcon.htm).

Endnotes
4-1

Chapter 4 - 

Human Health
■ A pollutant's impact may

range along a continuum

from no effect to mild

symptoms to serious acute

or chronic impacts. Different

people have different vulnerabilities, so some may

experience effects at ambient pollutant levels while others

may not.

■ Researchers have had success elucidating the linkage

between individual pollutants and health. In reality, however,

people are more typically exposed to a number of pollutants. How pollutants interact, and how exposure to multiple pollutants affects health, is not well understood at

present. 

EPA is working to lay the foundation for developing effective

measures for tracking progress in protecting human health

from environmental pollution. These include measures of outcomes, such as diseases, as well as biomonitoring measures

that can tell us, for example, how much of a certain pollutant

has penetrated into and resides within our

blood and tissue. 

This chapter describes key elements that

begin to establish a basis for developing

and using environmental public health

indicators:

■ The chapter begins with an overview of

the major trends and indicators for

health and disease in the U.S. 

■ Next, the chapter examines the role of

the environment in disease. Understanding the linkage between exposure

and health effects is a critical foundation for the development and use of

environmental public health indicators. 

Chapter 4 - Human Health

4-2

EPA’s Draft Report on the Environment 2003

Introduction

P

rotecting the health of Americans from environmental

pollutants has always been a key goal of EPA policies and

programs. EPA has taken a number of actions to fulfill this

goal, including establishing standards for pollutants in the

environment, requiring sources to limit their pollution, and

educating members of the public about actions they can take

to protect their health. The indicators presented in Chapters

1 through 3 provide a measure of the progress that has been

made in reducing environmental pollution in air, water, and

land. 

EPA is moving, where possible, to supplement the measures

described in the earlier chapters with outcome indicators that

could provide a clearer understanding of how environmental

factors contribute to public health outcomes such as disease

trends. Information on whether particular death and disease

rates are going up or down, along with information on the

various environmental and other factors that influence these

trends, would strengthen environmental decision-making and

evaluation. For example, this type of information could help

EPA evaluate not only whether air quality has improved, but

also whether rates of respiratory problems associated with air

pollution have improved, and if not, why.

Developing these types of outcome

measures is challenging for many reasons:

■ Although numerous health problems

have suspected links to environmental

pollution, many factors in addition to

the environment influence whether a

person who comes in contact with a

pollutant will ever show symptoms of

exposure or develop disease. Those

factors include the quantity and type

of pollutant, the number of contacts

with it, and a person's age, health,

genetic make-up, and lifestyle.

Introduction

Chapter 4: Human Health

Health Status of the 

United States

Environmental Pollution 

and Disease

Measuring Exposure to

Environmental Pollution

Challenges in Developing 

Human Health Indicators
4-3

Chapter 4 - Human Health

EPA’s Draft Report on the Environment 2003

■ Examples are presented that demonstrate this linkage and

illustrate how environmental health indicators can strengthen environmental management decision-making and evaluation. 

■ Then, the chapter describes the approaches to measuring

exposure to environmental pollution. A number of these

approaches may provide the basis for environmental public

health indicators in the future.

■ Finally, the chapter concludes with a section on the scientific and data-gathering challenges that lie ahead in developing and using environmental public health indicators.

Changes in the health of a nation's people, both improvements and declines, can take years to detect, and EPA cannot

develop this national overview alone. For example, nearly all of

the health and exposure information currently available is collected by other federal and state agencies, such as the

Centers for Disease Control and Prevention (CDC). Development and use of environmental public health indicators will

require continued effective coordination and collaboration

among federal and state agencies.

Health Status of the United States

Health Status of the United States

T

here are several ways to assess the health of a specific

group of people or an entire country's population that

are used consistently across the world as indicators of

health status. They include how long people can expect to

live (life expectancy), how many infants die before their first

birthday (infant mortality), the major causes of death, and

the amount of illness in a national population. Among the

most common measurements is the number of deaths caused

by disease. The national death rate for a disease—especially

if the numbers of early deaths (deaths before the average life

expectancy) are high—can be a warning of health problems.

This section presents an overview of health and major disease

trends in the U.S. Some important diseases are presented

that have a major impact on the health of Americans. It is

important to note that environmental factors may not play a

role in all diseases or causes of death presented in this section.

What are the trends and

indicators for health and

disease in the United States?

The overall health status of the U.S. today is generally good

and improving. Over the past century, the nation has basically

conquered many infectious

diseases that once sickened

or killed thousands of people: childhood diseases such

as measles and mumps, and

waterborne ailments such as

typhoid and cholera.

Significant progress in

improving sanitation and

drinking water means that

Americans are now relatively

safe from the diarrheal diseases that imperil much of

the world. Accidents are now

the leading threat to children in the U.S., and most

adults die from chronic illnesses rather than from

infectious diseases (Exhibit

4-1). At the turn of the century, many people died from

infectious diseases such as

tuberculosis and influenza.

Today more than 60 percent

of all U.S. deaths are attribHealth Status of the

United States:

Selected Indicators

Life expectancy

Cancer mortality

Cancer incidence

Cardiovascular disease mortality

Cardiovascular disease prevalence

Chronic obstructive pulmonary

disease mortality

Asthma mortality

Asthma prevalence

Cholera prevalence

Cryptosporidiosis prevalence

E. coli O157:H7 prevalence

Hepatitis A prevalence

Salmonellosis prevalence

Typhoid fever prevalence

Shigellosis prevalence
Because many infectious diseases are controlled and Americans are living longer, it is not surprising that chronic health

problems, which are often associated with aging (e.g., heart

disease, cancer, stroke, and lung disease), are among the

leading causes of illness and death. Some conditions are

wholly or partly the result of individual choices about smoking, diet, or exercise, but other health problems may also be

associated with exposure to environmental pollutants. 

The trend data for the diseases presented in this section provide a valuable national overview of the U.S. population.

Exhibit 4-3 summarizes the national trends for death rate

(number of people dying per year), and incidence rate (number of people developing the disease per year) or prevalence

(part of the population affected by a condition or disease).

Exhibit 4-4 shows trends in death rates for people age 65

and older.

Chapter 4 - Human Health

4-4

EPA’s Draft Report on the Environment 2003

Health Status of the United States

uted to cardiovascular diseases—those involving the heart

and blood vessels—and cancer.1

Infant mortality (death) and life expectancy are two key indicators of any nation's overall health (Exhibit 4-2). Infant mortality has dropped to the lowest level ever recorded in the

U.S.,2 but U.S. rates are still higher than those of other developed countries. In 1998, the U.S. ranked 28th out of 38

countries with available statistics for infant mortality.3

American life expectancy continues to improve. In the last

century, life expectancy at birth increased from 51 to 79.4

years for women and from 48 to 73.9 years for men.4

However, Americans still have a somewhat lower life expectancy than those of other developed countries.5 In 1997, the

U.S. ranked 19th for both males and females in life expectancy, compared with 30 other countries or geographic areas of

at least 1 million people. (The U.S. numbers are within 2

years of the life expectancy of 13 and 14 other countries for

females and males, respectively.)6

Exhibit 4-1: Causes of death, United States, 1900 and 1998 

0 10 20 304050

Pneumonia and influenza

Tuberculosis

Gastritis, enteritis, colitis

Heart diseases

Symptoms, senility, ill-defined conditions

Vascular lesions affecting central nervous system

Chronic nephritis and renal sclerosis

Unintentional injuries

Malignant neoplasms

Diptheria

0 10 20 304050

Other casues may include typhoid fever, measles, homicide, suicide, syphilis, and diabetes.

Includes cirrhosis.

Other causes may include motor vehicle accidents, AIDS/HIV, septicemia, Alzheimer's disease, and Parkinson's disease.

Source: CDC, National Center for Chronic Disease Prevention and Health Promotion. Unrealized Prevention Opportunities: Reducing the Health and Economic Burden of Chronic 

Disease. November 2000. Data for 1990 from U. S. Bureau of the Census; data for 1998 from National Center for Health Statistics.

19001998

Percentage of all deaths Percentage of all deaths

All other causes

Total 

cardiovascular 

diseases All cancers

Chronic obstructive pulmonary disease

Unintentional injuries

Pneumonia and influenza

Diabetes mellitus

Suicide

Nephritis and nephrosis

Chronic liver disease

Homicide

All other causes
4-5

Chapter 4 - Human Health

EPA’s Draft Report on the Environment 2003

Cancer

National cancer death rates declined overall during the

1990s,7 but cancer is still the second-leading cause of death

in the U.S., and the number of people who develop cancer

each year has actually increased since 1973.8 Although the

overall death rates have dropped for some types—leukemia

and breast, cervical, colorectal, stomach, and uterine cancers—the death rates for lung cancer and skin cancer, the

most common type of cancer in the country, have increased.9

The number of people developing cancer shows the same

mixed results for different subsets of the U.S. population. For

example, lung cancer rates have declined for men but

increased for women since 1973, and leukemia rates have

declined among adults but not among children.10

Cardiovascular Disease

Cardiovascular diseases (CVD) are any that involve the heart

and blood vessels. Examples are high blood pressure and

hardening of the arteries, which can lead to heart attacks,

strokes, and disability. Until age 65, more men than women

Health Status of the United States

Exhibit 4-2: Life expectancy and infant mortality in the United States

a. Life expectancy at birth and at 65 years of age by sex: 

United States, 1901–1999 b. Infant mortality rates: United States, 1950–1999 Life expectancy in years

19011910192019301940195019601970198019901999

100

80

60

40

20 Deaths per 1,000 live births 100

10

Note: Infant is defined as under 1 year of age.

Males

Males

Females

Females

Life expectancy

at birth

Life expectancy

at 65 years

195019601970198019901999

Source: Pastor, R.N., et al. Chartbook on Trends in the Health of Americans. Health, United States, 2002. 2002.

Health Data: Disease Mortality Versus

Disease Morbidity 

Disease mortality (death). This is an easy and reliable outcome to

measure; reporting deaths is a legal requirement supported by a

national collection system. A sudden increase in deaths due to identical causes in one geographic region can alert health officials to an

environmental problem, such as a waterborne disease outbreak. But in

completing death certificates, officials may not always be aware of

underlying factors such as environmental exposure or genetic factors

as potential causes of birth defects or death. 

Disease morbidity (illness). Morbidity data—the number of people who have a particular illness—can be useful in linking current

health conditions to possible environmental factors, in analyzing disease trends, and/or identifying factors that cause specific diseases or

trends. For example, the decline in lung cancer in men has been related

to the decline in smoking. But such data are not always available and

are frequently reported without causal association. State and federal

agencies may ask hospitals and clinics to report admitted cases of

asthma, heart attacks, cancer, or other diseases, but such requests

lack the force of law in many states. Full reporting in one geographic

area may create the false impression of a hot spot for a certain disease, whereas poor or underreporting masks the incidence of disease

nationwide.
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Health Status of the United States

1975-1998 1990-1998 1973-1998 1950-1998 1980-1998 

1980-2001 1997-1999 

F=Females; M=Males 

*Incidence trend is reported, unless specified otherwise. Incidence is the number of new cases 

of a disease in a given time period. 

**Rates for specific cancers may vary from these trends.

***Prevalence is the part of the total population affected by a condition or disease.

Note: Environmental pollutants may be only one small contributor to health effect trends.

Sources: NIH, National Cancer Institute, Surveillance, Epidemiology, and End Results (SEER) 

Program, 1973-1998; CDC, National Center for Health Statistics (NCHS), National Vital 

Statistics Systems (NVSS), 1950-1998; CDC, NCHS National Health and Interview Surveys, 

1980-2001.

Exhibit 4-4: U. S. death rates due to leading causes of 

death among persons 65 years of age and over, 

1950–1999 Deaths per 100,000 population

19501960197019801985199019951999

10,000

1,000

Note: Causes of death shown are the five leading causes of death among 

persons 65 years of age and over in 1999. Data are plotted on the log 

scale.

Source: Pastor, R.N., et al. Chartbook on Trends in the Health of Americans. 

Health, United States, 2002. 2002.

Heart disease

Stroke

Cancer

Influenza and pneumonia

Chronic lower respiratory diseases

Disease National Trend

Death Rate Incidence*

Disease National Trend

Death Rate Prevalence***

Decreasing

(children and adults )**

Increasing

(children and adults )*

Cancer (overall)

Cardiovascular Diseases 

(CVD)

(Heart Disease)

Increasing Increasing (F

Decreasing (M

Lung Cancer

Skin Cancer Increasing Increasing

(Melanoma)

Increasing (children

Decreasing (adults

Decreasing 

(adults

Blood Cancer

(Leukemia)

Decreasing Not reported

Respiratory/Lung 

Diseases

Chronic Obstructive 

Pulmonary Disease 

(COPD), including chronic 

bronchitis and emphysema

Increasing Not reported

Asthma Increasing

(children and adults)

Prevalence Increasing

(children) 

Prevalence Decreasing

(adults) 

Exhibit 4-3: Select disease trends
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have CVD, but after that age, the percentages are the same

for women and men. After age 74, a higher percentage of

women than men have CVD. The overall mortality trend for

CVD has declined dramatically since the 1950s (Exhibit 4-4).

Advances in the prevention and treatment of heart disease

and stroke rank among the major public health achievements

of the 20th century.11 Heart disease remains the leading

cause of death in the U.S., and stroke is third.

Respiratory and Lung Diseases

Chronic obstructive pulmonary disease (COPD) encompasses

a group of health conditions such as obstructed airflow and

breathing-related symptoms. Chronic bronchitis and emphysema, for example, are classified as COPD. In 1999, COPD was

the fourth-leading cause of death in the U.S.12 Between 1980

and 1998, death rates for COPD

increased for all racial and ethnic

groups in the nation, reflecting in large

part the effects of cigarette smoke.13,14

Death rates for males began to decline

slightly between 1993 and 1998; by

contrast, death rates for females have

steadily increased since 1980.15

Mortality data may not give a complete picture of the environmental

impact of the disease, because many

people with COPD have progressive

disability, not immediate death. 

Asthma 

Asthma is a disorder of the respiratory system characterized

by labored breathing, wheezing, cough, and pain or tightness

in the chest. It is a common chronic disease in children, and

in adults it is more common in females and African Americans.

Although the number of adults with asthma has declined

slightly since 1997, childhood asthma is on the rise.16 Asthma

death rates for adults have also increased since 1980. The

groups that have the highest incidence, women and African

Americans, also have the highest death rates.17 The prevalence of asthma shows regional differences; it is highest in the

Northeast and lowest in the South. In addition, in a 1996

survey, people who lived in a central city reported a higher

percentage of asthma cases than those who lived elsewhere.18

Health Status of the United States

Asthma is believed to have a genetic component, but airborne

allergens and irritants in the home, workplace, and community

can aggravate the disease and trigger attacks. 

Gastrointestinal Illnesses 

The gastrointestinal tract includes the mouth, esophagus,

stomach, small intestine, and the large intestine. Gastrointestinal infections and illnesses are caused by several types

of microorganisms (bacteria, viruses, and parasites). The

Notifiable Disease Program has recommended seven gastrointestinal illnesses caused by microorganisms for reporting:

cholera, cryptosporidiosis, E. coli O157: H7, hepatitis A, salmonellosis, shigellosis, and typhoid fever. These seven illnesses are indicators of gastrointestinal illness prevalence. They

can cause vomiting, diarrhea, fever, and dehydration, and they

are transmitted primarily by water or

food contaminated with feces or by

personal contact with an infected person or animal. Untreated human

sewage and runoff, especially when it

contains animal wastes, are sources of

contamination. Cholera and typhoid

fever rarely occur in the U.S. but are

included because they can be severe

illnesses and because a sudden

increase in reported cases could flag a

public health problem. The number of

deaths attributed to microorganisminduced gastrointestinal illnesses recently increased in the

U.S., after decades of relatively stable death rates.19 The

increases were particularly dramatic in young children (less

than 6 years of age) and older Americans (more than 65

years of age). Many cases of gastrointestinal illnesses go

unreported or are not diagnosed, making it difficult to estimate the number of people affected every year. 20,21 Often,

depending on the severity of symptoms, an infected person

may not visit a doctor or hospital, which further contributes

to the underestimation of gastrointestinal illness.
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What are the trends for

children's environmental health

issues?

Important environmental health issues for children include

infant mortality, low birth weight, childhood cancer, childhood

asthma, and birth defects. Since 1950, infant mortality has

steadily declined in the United States. Disorders related to

premature birth or low birthweight are the second-leading

cause of infant death, after birth defects. The number of low

birthweight infants born each year increased between 1991

and 2000, with the greatest increase for white infants. 22

Despite that increase, rates of infant mortality and low birthweight for African American infants are more than twice those

for white infants. 23

Death rates for childhood cancer have declined since 1975,

largely because of improved treatment. 24 During the same

period, however, the number of children who develop cancer

each year has risen. Leukemia, lymphoma, and central nervous

system cancers are the most prevalent types of childhood

cancer. 25 In 1999, cancers were the second-leading cause of

death for children between 5 and 9 years of age and the

third-leading cause of death

for children between 1 and

4 years of age.26

Identified asthma prevalence

in children has increased

since 1980, especially for

children age 4 and younger

and for African American

children (Exhibit 4-5).27 In

2001, approximately 6 million—or 9 percent—of U.S.

children less than 18 years

old had asthma, compared

to approximately 3.6 percent of children in 1980.28

The number of children ever

diagnosed with asthma by a

health professional—

referred to as asthma lifetime diagnosis—has also increased

slightly since 1999. However, the number of children having

asthma attacks seems to have leveled off since 1997.29

Researchers do not understand completely why children

develop asthma or why asthma prevalence has increased in

the past two decades. The tendency to develop asthma can

be inherited, and several factors may trigger acute asthma

attacks, such as dander from dogs and cats, house dust mites

(microscopic animals living in indoor house dust), cockroach

allergens, and pollen.30,31 Researchers also believe that air

pollutants such as environmental tobacco smoke (ETS), particulate matter, and ozone may increase the severity or frequency of asthma attacks in children who have the

disease.32,33,34

It is important to note that air quality has generally improved

during the time that asthma prevalence in children has

increased. For example, over the past 20 years, levels of criteria pollutants (including ozone and particulate matter) have

decreased. Also, children's exposure to ETS has declined

since the 1980s, as evidenced by a national decline in children's blood cotinine levels, an indicator that measures exposure to ETS. While on the surface, this appears to suggest

Health Status of the United States

Children's

Environmental

Health: Selected

Indicators

Infant mortality

Low birthweight incidence

Childhood cancer mortality

Childhood cancer incidence

Childhood asthma mortality

Childhood asthma prevalence

Deaths due to birth defects

Birth defect incidence

Why Children May Be Especially Vulnerable to

Some Environmental Pollutants

■ Children's nervous, immune, digestive, and other systems are still

developing, which may reduce their natural protection and ability to

process or inactivate some pollutants. 

■ Children eat more food, drink more fluids, and breathe more air in

proportion to their body weight than adults, and they have a more

rapid metabolism, which can increase their exposure to some pollutants, but can also reduce exposure to other pollutants. 

■ Children's behaviors, such as crawling and placing their hands and

objects in their mouths, may allow more pollutants to enter their

bodies.
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that air pollution is not related to the incidence or prevalence

of asthma, there are too many complexities and uncertainties

to draw this conclusion. For example,

although air quality has improved at a

national level, areas such as inner cities,

where there is a higher prevalence of asthma,

continue to experience intermittent exposure

to poorer air quality, which may contribute

to asthma prevalence. It is also possible that

other environmental factors may make children more sensitive to air pollution;

increased sensitivity could cause asthma

rates to rise even as ambient air quality

improves. For example, indoor air pollutants

that are not monitored at a national level

may trigger asthma attacks (in addition to

tobacco smoke, which is monitored, as discussed previously). 

Health Status of the United States

Exhibit 4-5: Asthma prevalence, 1980-1996, asthma lifetime diagnosis, current asthma, and asthma attack prevalence, 1997-2001, in children Number of children with asthma per 1000 children 17 years of age or younger

198019811982198319841985198619871988198919901991199219931994199519961999 1997 2000 2001 1998

20

40

60

80

100

120

140

Note: The survey questions for asthma changed in 1997; data before 1997 cannot be directly compared to data in 1997 and later.

Source: Based on and updated from Akinbami, L.J. and K.C. Schoendorf. Trends in Childhood Asthma: Prevalence, Health Care Utilization and Mortality. 2002. Data from 

CDC, National Center for Health Statistics, National Health Interview Surveys, 1980-2001.

Asthma prevalence

Asthma lifetime diagnosis

Asthma attack prevalence

Current asthma prevalence

Birth defects are the leading cause of infant mortality,

accounting for almost 20 percent of all such deaths in

1999.35 Defects that occur most often are

those that affect the heart and lungs. A

large number of birth defects may be due

to genetic factors. It is unclear at this time

what role environmental pollutants have in

developing birth defects, but some studies

suggest possible environmental links.

Because some birth defects are not recognized immediately, they are underreported

on birth an death certificates, and the overall problem may be underestimated.36,37

Also, many serious birth defects are not evident until later in life—an additional factor

in underreporting.
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Many studies in people have demonstrated an association between environmental exposure and certain diseases or other health problems. Examples

include radon and lung cancer; arsenic and cancer in several

organs; lead and nervous system disorders; disease-causing

bacteria such as E. coli O157: H7 (e.g., in contaminated meat

and water) and gastrointestinal illness and death; and particulate matter and aggravation of heart and respiratory diseases. 

To understand the relationship between

health and the environment, scientists study

a series of events that begins with the

release of a pollutant into the environment

and may end with the development of disease in a person or a population. Exhibit 4-6

broadly illustrates these events: (1) release

of pollution into the environment (air, water,

food, soil, and dust), (2) exposure through a

variety of activities (inhalation, skin contact,

and ingestion of contaminated media), and

(3) the development of disease or other

health problems. 

Elucidating the linkage between environmental pollution and

disease is challenging. We

understand this linkage fairly

well for some pollutants,

such as those listed above,

but poorly for others. This

section describes some of

the challenges to elucidating

those linkages, and uses

examples to highlight the

role that indicators can play

in strengthening our understanding of that linkage and

in supporting environmental

management efforts. 

What is the role of the

environment in disease?

Decades of research have provided the scientific foundation

for understanding the role of the environment in disease. For

many pollutants, scientists know with some certainty that

exposure to these pollutants, at sufficiently high concentrations, can cause a variety of health effects. For other pollutants, where scientific evidence is less

conclusive, scientists can only establish an

“association” between exposure and health

problems. 

Some effects on health may be short-term

and reversible, such as irritated eyes from

smog. Other effects, such as emphysema,

heart disease, and cancer are chronic or

even fatal. Some effects may appear shortly

after exposure. Others, such as cancer, may

require a long lead time before the disease

appears. 

In many cases, pollution likely is just one of several factors—

including diet, exercise, alcohol consumption, and genetic

make-up—that influence whether an exposed person will ever

become sick. Although exposure to ETS is associated with

lung cancer, whether a person will develop cancer from that

exposure depends on the amount, frequency, and length of

exposure, exposure to other contaminants, and personal characteristics (genes) and behavior (diet and other lifestyle

choices).38 All these factors can be important in illness and

premature death, but they are poorly understood, difficult to

quantify, and not routinely tracked or reported. Because of

these complexities, it is very difficult to establish causal relationships, and few diseases are known to be exclusively the

result of exposure to an environmental pollutant. In many

cases, only a small portion of the national incidence of a particular disease is likely to be attributed to a specific environmental factor. 

Environmental Pollution and Disease

Environmental

Pollution and

Disease: Selected

Indicators

Blood lead level

Cardiovascular disease mortality

Chronic obstructive pulmonary

disease mortality

Cholera prevalence

Typhoid fever prevalence

Environmental Pollution and Disease
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Environmental Pollution and Disease

Pollution generated enters 

air, water, land, food

People exposed to 

pollution via inhalation, 

skin contact and/or 

consumption of 

contaminated food (e.g., 

fish) or media

Potential health 

effects

Exhibit 4-6: Pathway from pollution to exposure to potential health effects
Chapter 4 - Human Health

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Further complicating the picture is the fact that several segments of the population may be at higher risk for damage or

disease from environmental pollutants. Potentially sensitive

groups include children; older Americans; people with existing

health problems such as diabetes, respiratory disease, or

heart disease; and persons with compromised immune systems, including those who have HIV/AIDS or are undergoing

cancer chemotherapy. Poor or other disadvantaged populations may live in more polluted environments that expose

them to higher concentrations of pollutants. Understanding

the impacts of pollutants on such sensitive groups is important for those people directly, as well as for the development

of protective national health standards and policies. 

Children may be more vulnerable to some environmental pollutants than adults for a number of reasons related to their

size, growth, and behaviors. Further, children may become ill

from exposures that would not affect adults. 

Older Americans may also be especially vulnerable to harmful

health effects associated with environmental pollutants, in

part because some health problems take many years to develop. A long life span may provide the time needed for occupational or cumulative environmental exposures to induce illness

or disease. Also, because of medical advances, many older

Americans may be living with health conditions that previously shortened life spans. And, older Americans may have preexisting conditions—such as heart ailments, diabetes, or

respiratory disease—that reduce their tolerance to pollutants. Even relatively healthy older people may, merely as a

result of age, have a diminished capacity to fight infections,

pollution, or other causes of stress to their systems that

might have posed little risk when they were younger. Harmful

substances may be processed and eliminated from the body

more slowly in older people, which can prolong exposure to

those substances and increase susceptibility to associated

health problems. Older people are also more likely to become

dehydrated and experience other serious consequences of

gastrointestinal disease.

Sorting out the role of all these risk factors—including the

environment—and their interactions is a major challenge of

scientific research. In addition to the tools already available

for elucidating the linkage between environmental exposure

and disease, EPA is exploring the use of indicators to complement the traditional tools—exposure assessment, toxicology,

and human studies—that are used to evaluate the potential

impacts of environmental exposures. Three examples are presented below that illustrate how indicators can play a role in

elucidating linkages between environmental pollution and

health problems. In two of these examples (lead and waterborne diseases), indicators also play a key role in focusing the

environmental protection decision and in evaluating the success of those decisions.

Health Effects of Exposure to Lead

Lead, a naturally occurring metal, has been used to produce

gasoline, ceramic products, paints, and solder. In homes built

before 1978, lead-based paint and lead-contaminated dust

from paint are the primary sources of exposure to lead. Major

initiatives have been implemented to reduce lead exposure by

phasing lead out of gasoline, paint, solder, and plumbing fixtures. 

Health problems from lead exposure are a major environmental health problem because exposure to lead is widespread

and can cause health effects at relatively low levels. Substantial data are available to link lead exposure with health

effects. Lead adversely affects the nervous system, can lower

intelligence, and has been associated with behavioral and

attention problems. It also affects the kidney and blood-forming organs.39 Children and the developing fetus are more vulnerable to the effects of lead than adults. 

The level of lead in blood has long been used as an indicator

of exposure to lead. And, because the linkage between lead

exposure and health effects is so strong, blood lead is also

used as an indicator of adverse effects on the nervous system. 

In the 1970s, lead poisoning occurred increasingly in children

who did not live in dwellings with lead-based paint, suggesting that another source or sources of lead exposure were of

even greater concern than lead paint. Research found that

combustion of leaded gasoline was the primary source of lead

in the environment. In the 1970s, EPA promulgated regulations to ban lead in gasoline. Since that time, concentrations

of lead in blood samples and in ambient air have declined significantly (Exhibit 4-7). In young children, the median concentration of lead in blood decreased by 85 percent from

1976 to 1999–2000 based on nationwide surveys (Exhibit

4-8).40

Environmental Pollution and Disease
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But national averages of blood levels tell only part of the

story. Between 1999 and 2000, approximately 430,000 children ages 1 to 5 (about 2 percent) had elevated blood lead

levels (10 μg/dL or greater) from eating paint chips or inhaling lead-containing dust in older homes, primarily in urban

areas.41 Even today, lead poisoning is considered to be a serious environmental hazard in young children in the U.S.42

Several major metropolitan areas, including Chicago, Detroit,

Milwaukee, Palo Alto, and St. Louis, are evaluating blood lead

levels of young children, focusing on areas at high risk (i.e.,

older housing and poorer neighborhoods), to study and

address potential problems (see box, “Children’s Lead Levels

Remain a Concern in Urban Hot Spots”). These blood lead

screening programs, however, do not report in a systematic

fashion to a central location where the data can be evaluated.

Health Effects of Air Pollution

Several outdoor air pollutants are associated with harmful

health effects. These include the six “criteria” pollutants—

particulate matter, ground-level ozone, nitrogen dioxide, carbon monoxide, sulfur dioxide, and lead—for which EPA has

established standards to protect human health, including the

health of sensitive populations such as asthmatics, children,

and the elderly. The burning of fossil fuels is the principal

Environmental Pollution and Disease

Age-adjusted rates per 100,000 people

19761977

Year

197819791980

50

60

70

80

110

100

90

10

12

13

16

15

14 Total lead used per 6-month period (thousands of metric tons)Average blood lead, micrograms per deciliter ( g/dL) Blood lead concentrations, micrograms per deciliter ( g/dL)

Lead used in gasoline

Average blood lead ( g/dL)

30

1976- 

1980

1988- 

1991

1992- 

1994

 1999-

2000

25

20

15

101,2

Exhibit 4-7: Lead used in gasoline production and National Health and Nutrition Examination Survey 

(NHANES) blood lead averages, 1976-1980

Exhibit 4-8: Concentration of lead in blood of children age 5 and under, 1976-1980, 1988-1991, 1992-1994, 1999-2000

90th percentile (10 percent of 

children have this blood lead level 

or greater)

Source: National Research Council. Measuring Lead Exposures in Infants, 

Children and Other Sensitive Subpopulations. 1993.

10 g/dL of blood lead has been identified by CDC as elevated, which indicates 

the need for intervention. (CDC. Preventing Lead Poisoning in Young Children.

1991.)

Recent research suggests that blood levels less than 10 g/dL may still produce 

subtle, subclinical health effects in children. (Schmidt, C.W. Poisoning Young Minds.

1999.)

Source: EPA. America's Children and the Environment-Measures of Contaminants, 

Body Burdens, and Illnesses, Second Edition. February 2003. Data from CDC, 

National Center for Health Statistics, National Health and Nutrition Examination 

Survey, 1976-2000.

Median value

(50 percent of children 

have this blood lead level 

or greater)
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source of these pollutants. Air pollutants can be transported

long distances, so they can potentially have effects distant

from their source. (See Chapter 1 – Cleaner Air, for further

discussion of the health effects related to air pollutants.)

Air pollution has been associated with several health problems, including reported symptoms (nose and throat irritation), acute onset or exacerbation of existing disease (e.g.,

asthma, hospitalizations due to cardiovascular disease), and

premature deaths. The impact of air pollution on health was

underscored in December 1952 when a slow-moving area of

high pressure came to a halt over the city of London. Fog

developed over the city, and particulate and sulfur pollution

began accumulating in the stagnating air mass. Smoke and

sulfur dioxide concentrations built up over 3 days. Mortality

records showed that deaths increased in a pattern very similar

to that of the pollution measurements. An estimated 4,000

extra deaths occurred over a 3- to 4-day period. This represents the first quantitative air pollution exposure data with a

link to health. 

While the London episode highlighted the hazard of extreme

air pollution episodes, it was unclear whether health effects

were associated with lower concentrations. By the 1970s, the

association between respiratory disease and particulate

and/or sulfur oxide air pollution had been well established.43

Improvements in the measurement of air pollution and health

endpoints, plus advances in analytical techniques, have made

it possible to quantitatively evaluate air pollution and health.

For example, research has shown that many air pollutants may

contribute to the onset or aggravation of heart disease,

especially carbon monoxide and fine particulate matter

(PM2.5).44, 45, 46

Environmental Pollution and Disease

Children's Lead Levels Remain a Concern in Urban Hot Spots

Because lead in outdoor air has been reduced to very low levels, the

lead dangers to children today are primarily from ingesting and inhaling

lead-containing paint dust or eating paint chips in older homes, most

of which are in urban areas. Several metropolitan health departments

are addressing the problem by using geographic information systems

and maps depicting areas of housing with potential lead hazards, as

well as areas where children's blood lead levels are high (based on testing of the general population), to identify high-risk areas and promote

compliance with lead hazard regulations. In Chicago, for example, EPA

Region 5, the U.S. Department of Housing and Urban Development,

and the city have taken enforcement action against property managers

and landlords who did not disclose potential lead hazards to tenants.

The city is also providing outreach and education materials to these

high-risk areas. The percentage of Chicago children with elevated blood

lead levels above10 μg/dL has declined substantially since 1996,

although many still have blood lead levels above the national average

(Exhibit 4-9). Percent of children with lead poisoning

Note: 10 μg/dL of blood lead has been identified by CDC as elevated, which indicates 

the need for intervention. (CDC. Preventing Lead Poisoning in Young Children. 1991.)

Source: Graphic developed for this report by Chicago Department of Public Health, 

Childhood Lead Poisoning Prevention Program. For 1996-2001, source is annual Illinois 

Department of Public Health, Childhood Lead Poisoning Surveillance Reports. For 

1999-2000, source is CDC. Second National Report on Human Exposure to Environmental 

Chemicals. 2003. Data from CDC, National Health and Nutrition Examination Survey 

(NHANES).

0

5

1996 1997 1998 1999 2000 2001 National Estimate

1999-2000

10

15

20

25

30

(Children aged 0-6 years old)

Exhibit 4-9: Percent of screened children in Chicago 

having elevated blood lead levels greater than 10 micrograms per deciliter (> 10 μg/dL), 1996−2001
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Particulate Matter

Particulate air pollution is associated with increased daily

mortality in many U.S. communities and other countries. The

elderly and those with preexisting diseases are particularly

vulnerable.47 Exposure to ambient particulate matter has also

been associated with an increased number of hospital admissions and visits to doctors due to cardiovascular problems

and respiratory disease.48 Some studies show that exposure

to particulate matter exacerbates asthma. Long-term exposure

to particulate matter has been associated with increased

deaths from heart and lung diseases, increased respiratory

disease and bronchitis and with decreased lung function in

children.49

Ozone

Repeated short-term exposures to ozone may damage children's developing lungs, which may lead to permanent reductions in lung function.50 Controlled studies in healthy adults

have demonstrated ozone-induced lung inflammation, decrements in lung function, and associated respiratory symptoms,

such as cough and pain on deep inspiration.51 Ozone exposures have also been associated with an increased number of

hospital admissions and visits to doctors.52

Indicators

As noted in Chapter 1 – Cleaner Air,

national average criteria pollutant levels, including particulate matter and

ozone levels, have decreased over the

past 20 years. As discussed earlier,

however, there are limitations in using

these national air pollution data to

evaluate rates of asthma attacks

occurring during acute exposure

episodes. Possible future health indicators for air pollution include death

due to respiratory and cardiovascular

disease, increased hospital admissions

for respiratory and cardiovascular disease, and subtle changes in the cardiovascular system that can increase

people's risk of heart attacks and

other cardiovascular effects. Use of these indicators is still

challenged by limits in our understanding of how much air

pollution contributes to the risk of cardiovascular and respiratory disease.

Waterborne Diseases 

In the early 20th century, waterborne diseases such as cholera

and typhoid fever were major health threats across the U.S.

Deaths due to diarrhea-like illnesses, including typhoid,

cholera, and dysentery, were the third largest cause of death

in the nation. For instance, more than 150 in every 100,000

people died from typhoid fever each year.

Around that time, scientists began to understand the cause

of these diseases. They had identified the bacteria responsible for most diarrheal deaths (typhoid, cholera, and dysentery) and elucidated how these bacteria were transmitted to

and among humans. Infected and diseased individuals shed

large quantities of microbes in their feces, which flowed into

and contaminated major water supplies. This contaminated

water was then distributed untreated to communities, which

used the water for drinking and other purposes. This created

a continuous transmission cycle. 

Once treatment (filtration and chlorination) of drinking water was initiated to remove pathogens, the number

of deaths due to diarrheal diseases

dropped dramatically in communities

with treated water. Deaths due to

typhoid fever were tracked throughout the early 20th century, as drinking water treatment was implemented

across the country, providing an indicator of the success of this environmental management strategy (Exhibit

4-10). 

Drinking water treatment is one of

the great public health success stories of the 20th century. Not only did

it dramatically and significantly

reduce death rates from waterborne

disease, it also increased life

expectancy and reduced infant morEnvironmental Pollution and Disease
Chapter 4 - Human Health

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EPA’s Draft Report on the Environment 2003

Environmental Pollution and Disease

tality. Today, public health is protected against new and

emerging waterborne microbial contaminants by continual

improvements to the drinking water treatment process. 

This example illustrates how a link was made between gastrointestinal disease (an outcome indicator) and exposure to

pathogens in drinking water. Based on this connection, officials were able to take effective action to protect public

health. They also were able to use an outcome measure

(deaths due to typhoid) to monitor the success of these protective actions. 

Today, deaths due to typhoid, cholera, and dysentery are so

rare in the U.S. that they cannot serve as indicators to evaluate drinking water management decisions. The actual number

of cases of typhoid, cholera, and dysentery are tracked to

some extent; however, the reporting of these cases is not federally required. The waterborne disease outbreak surveillance

system is a passive system in that it relies on state health

departments to voluntarily report their outbreaks to CDC.

(For further information on waterborne diseases, see Chapter

2 – Purer Water.)

Exhibit 4-10: Percent of population with treated water versus typhoid deaths in the United States, 1880-1980 Typhoid deaths per 100,000 people Percent of population with treated water

100

10

90

80

70

60

50

40

30

20

10

1880189019001920193019401950196019701980

Year

Source: Craun, C.G. Waterborne Diseases in the United States. 1986; Whipple, G.C. Typhoid Fever - Its Causation. Transmission and Prevention. 1908; Fox, K. National Risk 

Management Research Laboratory, personal communication, 2003. 

Deaths

Percent
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Chapter 4 - Human Health

EPA’s Draft Report on the Environment 2003

How can exposure data advance

understanding of the role of the

environment in disease?

“Exposure” refers to direct human contact with a pollutant

(e.g., through breathing contaminated air, drinking contaminated water, or eating contaminated food). Measurements of

such exposures can help identify which pollutants may cause

health problems and at what levels. They can also provide the

basis for determining appropriate actions to limit exposure

and associated harmful health effects. For example, these data

can enable health officials to respond to a health threat in a

specific community (e.g., issue code red alerts when air pollution is a concern). This section describes the three key

approaches—environmental monitoring, personal monitoring,

and biomonitoring—that scientists use to measure how much

pollution we are exposed to and how exposure data contribute to understanding the role of the environment in disease. No approach is best suited to all pollutants. Different

approaches are appropriate to different types of pollutants,

and each approach has strengths and weaknesses. 

Environmental Monitoring 

Historically, human exposure has often been estimated

through environmental measurements of ambient pollutant

concentrations (e.g., particulate matter in air, bacteria in water

or food). However, the presence of a pollutant in the environment does not necessarily mean that anyone is exposed. For

example, people must actually breathe contaminated air or

ingest bacteria-laden food and water for exposure to occur. 

Monitoring ambient pollutant levels is critical to measuring

exposure for several pollutants, including air pollution (e.g.,

particulate matter, ozone, nitrogen oxides, and sulfur dioxide),

radiation, biological pollutants (e.g., molds, pollen, infectious

agents), and disinfection by-products, which are formed when

chlorine is used to treat drinking water. For instance, measurements of concentrations of pollutants in outdoor or indoor

air can be coupled with human activity patterns (e.g., time

spent working, exercising outdoors, sleeping) to estimate

human exposures. This approach was used to establish

national air and water quality standards for many pollutants

that protect the U.S. population from harmful health effects. 

Personal Monitoring

With personal monitoring, the monitoring device is worn by

individuals as they proceed through their normal activities.

This approach is most common in workplaces. The radioactivity sensors worn by nuclear power plant workers are one

example. Personal monitoring has been used to estimate total

human exposures, including exposures from the air people

breathe, the water they drink, and the food they eat.53 One

advantage of personal monitoring is that the data provide

valuable insights into the sources of the pollutants to which

people are actually exposed. A challenge with personal monitoring is ensuring that sufficient sampling is done to be representative of the population being studied.

Biomonitoring 

Several environmental pollutants, notably heavy metals and

some pesticides, can accumulate in the body over

time, often with increasing

risk of harm. These pollutants or their breakdown

products (i.e., metabolites

formed when a pollutant is

broken down in the body)

leave residues in the body

that can be measured, usually in the blood or urine.

These residues reflect the

amount of the pollutant in

the environment that actuMeasuring Exposure to Environmental Pollution

Measuring Exposure

to Environmental

Pollution: Selected

Indicators

Blood lead level

Blood mercury level

Blood cotinine level

Urine organosphosphate level to

indicate pesticides

Measuring Exposure to Environmental Pollution
Chapter 4 - Human Health

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EPA’s Draft Report on the Environment 2003

ally gets into the body. The approach of measuring pollutant levels in tissue or fluid samples

from individual people is called “biomonitoring.” 

National-scale biomonitoring data can be useful as indicators of the distribution of exposure

across the entire population to a variety of

pollutants. Also, such data provide an important bridge to understanding the relationships

between ambient pollutant concentrations

(e.g., in air, water), exposures to these pollutants, and health problems. Biomonitoring data provide exposure information that may help alert physicians, scientists,

and health officials to diseases that result from exposure to

environmental chemicals. The data are also useful for establishing reference ranges that can be used to identify people

with unusually high exposure or the percentage of the population that has pollutant exposures above levels considered to

be elevated (e.g., lead).54

Health and environmental agencies are using biomonitoring

measures and trend data to improve understanding of the

relationship between exposure to environmental pollutants

and health. For example, CDC is using biomonitoring data to

assess environmental pollutant exposures in the U.S. population. In 2001, CDC provided data on 27 pollutants present in

the blood and urine of a small sample of the U.S. population.55 In January 2003, CDC released data on blood and

urine residues for 116 environmental chemicals in a much larger, nationally representative population sample.56

Biomonitoring data are already available for metals (e.g., lead,

mercury, cadmium), cotinine (a measure of environmental

tobacco smoke [ETS]), volatile organic chemicals, organophosphate pesticides, organochlorine pesticides, phthalates,

polychlorinated biphenyls (PCBs), dioxin and dioxin-like compounds, and polycyclic aromatic hydrocarbons (PAHs). Future

biomonitoring will build the trend data showing whether levels

of other pollutants are increasing or decreasing in the population.

Although biomonitoring data are highly useful, they have several limitations as an indicator of exposure. These data do not

provide information about how the exposure occurred or the

source(s) of exposure, and in some cases, they do not distinguish among different pollutants that may leave identical

Measuring Exposure to Environmental Pollution

residues in the body. For example, biomonitoring can determine that a person has been

exposed to carbon monoxide, but not whether

the source is ETS, a faulty gas stove, or vehicle

emissions on a highway. These limitations may

make it difficult to identify actions that would

reduce or prevent such exposures or to correlate them to disease. Nonetheless, for some

pollutants national biomonitoring data are useful indicators of exposure on a national scale.

The following three examples—the heavy metals lead and mercury, ETS, and organophosphate pesticides—

highlight the findings of the ongoing CDC biomonitoring

efforts and how these findings can advance efforts to protect

human health.

Heavy Metals

Gathering information on heavy metals in the U.S. population is important

because those metals are highly toxic

at sufficiently high doses, and even

low-level residues of certain metals

may be of concern. Concentrations of

lead in blood—a demonstrated

indicator of harmful effects on the

nervous system—have declined significantly, especially since the 1970s, when lead was banned

from gasoline. 

Environmental exposure to mercury, another heavy metal, is of

particular concern. Mercury can be transformed into methylmercury by bacteria in soil and sediments and then can move

up the food chain, accumulating in fish, which are a major

source of exposure for people. Methylmercury has been associated with harmful effects on the nervous system, especially

in a developing fetus. When a pregnant woman eats

methylmercury-contaminated fish, the child she is carrying

may later experience harmful effects, including learning and

developmental problems.57 The same is true for young children exposed to methylmercury directly. Indigenous and tribal

populations and others who rely heavily on fish as a major

food source may also suffer nervous system effects. 

In 1999 and 2000, total mercury blood levels (both inorganic and organic forms) were evaluated in a nationally represen-
4-19

Chapter 4 - Human Health

EPA’s Draft Report on the Environment 2003

tative survey of approximately 700 young children (ages 1 to

5 years) and 1,700 women of childbearing age (16 to 49

years). The results show that the mercury levels in women of

child-bearing age were less than 58 ppb—a level associated

with a doubling of risk of abnormal performance on neurodevelopmental tests in children exposed in utero.58,59 Adverse

health effects may also occur at levels below 58 ppb. To

account for many uncertainties, EPA has determined that children born to women with blood levels of mercury above 5.8

ppb are at some increased risk of adverse health effects.

Based on the 1999–2000 survey, about 8 percent of women

of child-bearing age had at least 5.8 ppb of mercury in their

blood.60,61 Health officials have been working to promote

education and awareness of the hazards of methylmercurycontaminated fish. (See “Consumption of Fish and Shellfish”

in Chapter 2 – Purer Water.)

Environmental Tobacco Smoke

Environment tobacco smoke (ETS) is

of special concern in indoor air, where

it can concentrate and persist.

Cotinine, a breakdown product of

nicotine that can be quantified in

blood, hair, urine, and saliva, can be

used as a measure of exposure to

tobacco smoke from both active and

passive means. Overall, children's

median (50th percentile) blood levels of cotinine have

declined 56 percent between the periods 1988–1991 and

1999–2000 (Exhibit 4-11).62 Between the periods

1991–1994 and 1999–2000, cotinine levels in urine

decreased 58 percent for children ages 3 to 11, 55 percent

for adolescents ages 12 to 19, and by 75 percent in nonsmoking adults, according to a national survey of almost

6,000 people.63 The declines in children's cotinine levels are

in part attributable to the declining number of adult smokers.

However, non-smoking children between the ages of 3 and 19

have cotinine levels more than twice those of adults.64 In

1999–2000, African Americans (all age groups combined)

had cotinine levels more than twice those of whites.65

ETS is a known cancer-causing agent in people, and long-term

exposure to ETS is associated with an increased risk for lung

cancer and other diseases.66 Children are at particular risk

from ETS, which may exacerbate asthma in children who have

the disease and greatly increase the risk for lower respiratorytract illness, such as bronchitis and pneumonia, among young

children.67

Organophosphate Pesticides

Organophosphate pesticides account

for about half of the insecticides used

in the U.S. Exposure to these pesticides occurs primarily from ingestion

of food products or from home and

garden uses, like lawn and crack and

crevice treatments, although many

household uses are being phased out

or have stopped altogether in recent

years. In a 1999–2000 nationwide survey, common breakdown products of several organophosphate pesticides were

found in the urine of approximately 50 percent of the nearly

2,000 people sampled, demonstrating fairly widespread public exposure to these pesticides.68 This study also showed

that these pesticide residues were consistently higher in children than in adults.69 Like lead and mercury, these pesticides

can harm the nervous system, but it is not yet known what

minimum level causes these effects. Future research will build

the trend data showing whether levels of these pesticides are

increasing or decreasing in the population and, as noted,

CDC has an effort under way to collect those data.

Measuring Exposure to Environmental Pollution Serum Cotinine Concentrations (μg/mL)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

1988–1991 1999–2000

50th percentile 

(50 percent of children have this 

serum cotinine level or greater)

90th percentile 

(10 percent of children have this 

serum cotinine level or greater)

Exhibit 4-11: Concentrations of cotinine in children's blood, 

1988–1991 and 1999–2000

Source: EPA. America's Children and the Environment-Measures of Contaminants, 

Body Burdens, and Illnesses, Second Edition. February 2003. Data from CDC, 

National Center for Health Statistics, National Health and Nutrition Examination 

Surveys, 1988-1991 and 1999-2000.
Chapter 4 - Human Health

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EPA’s Draft Report on the Environment 2003

Human health indicators provide important tools that

regulatory agencies can use to identify environmental

health problems, develop programs to reduce the

problems, then gauge the success of those efforts. For example, the declining levels of lead in children's blood confirm

that the nation's strategies to remove lead from gasoline,

water, and paint have successfully reduced exposure to lead.

Similarly, the decline in urinary cotinine levels confirms that

efforts to reduce smoking have been successful in reducing

exposures to ETS.

For many other pollutants, major knowledge gaps and challenges remain in linking environmental pollution to health

problems. Sorting out the role of the environment, the role of

other factors (e.g., genetic make-up, lifestyle choices such as

diet and exercise), and the importance of their interactions

remains an enormous scientific challenge. The time between

exposure and the development or diagnosis of disease, as well

as the problems of tracking a mobile population, further complicate the issue of clarifying connections between exposure

and harm to health. An emerging area of science involves

examining the possible combined (additive), synergistic, and

cumulative effects of numerous pollutants in the environment.

This field of study merits greater development. Finally, not all

chemical exposures result in harm to health. With a better

understanding of the contribution of environmental factors to

the development of disease, EPA will be able to use established health outcome measures—disease trend and exposure

data—to enhance environmental management efforts and to

assess the effectiveness of those efforts. 

Disease registries could be improved to provide valuable

assistance in tracking many diseases. Currently, most disease

indicators are based on mortality data, which have serious

limitations for linking environmental exposures to disease.

Data on the number of new cases (incidence) of a disease or

the existing cases (prevalence) of a disease in a population

can provide better information, but no comprehensive nationwide systems exist for collecting these data. For example,

there is currently no national registry for birth defects. Also,

it is nearly impossible to get an accurate national picture of

the number of people affected by outbreaks of waterborne

diseases. Occurrence of endemic waterborne disease is grossly underreported. Submission of waterborne disease information to CDC is strictly voluntary, and state-level data pose

problems because the list of gastrointestinal diseases that

must be reported varies by state. Also, for an outbreak to be

detected, many people need to become ill at the same time,

and many cases go unreported or are not diagnosed. 

Better national-level disease data that could be linked directly

with environmental monitoring data would support efforts to

establish connections between disease and environmental

exposures. For meaningful comparisons, all data sets should

have similar timeframes (the same months or number of

years) and locations. Also, national-level efforts would benefit

from more data that can be sorted by several relevant factors,

such as race (which can help in identifying disparities in

health status and outcomes), income, occupation, and residence. Such data can be gathered only through better collaboration between and among environmental and health

agencies at all levels, as well as hospitals, clinics, and medical

offices. As EPA works to develop environmental indicators that

reliably signal trends in exposures and disease, the Agency

will also work to improve cooperation with the federal and

state agencies that collect relevant information.

Appropriate indicators that address these challenges can help

the agencies responsible for monitoring and managing the

nation's health to flag and respond to potential problems,

such as an upsurge in cases of an environmentally related disease or rising contaminant levels in human tissues. The same

indicators might, ideally, show whether pollution control

actions are actually reducing the number of people who

develop diseases associated with environmental agents. This

information will help EPA and other agencies to enhance

priority-setting to best protect the health of the nation's

people.

Challenges in Developing Human Health Indicators

Challenges in Developing Human Health Indicators 
4-21

Chapter 4 - Human Health

EPA’s Draft Report on the Environment 2003

13 Eberhardt, M.S., D.D. Ingram, D.M. Makuc, et al. Health,

United States, 2001: With Urban and Rural Health Chartbook,

Hyattsville, MD: National Center for Health Statistics, 2001,

161-163.

14 Pastor, P.N., et al. Chartbook on Trends in the Health of

Americans Health, United States, 2002, 2002. op. cit.

15 Ibid.

16 Mannino, D.M, D.M. Huma, L.J. Akinbami, et al. Surveillance

for asthma - United States, 1980-1999. Morbidity and

Mortality Weekly Report Surveillance Summaries 51(SS-1): 8, 9,

13 (2002).

17 Ibid.

18 Adams, P., G.E. Hendershot, and M. Marano. Current estimates from the National Health Interview Survey. 1996. Vital

and Health Statistics 10: 82, 92, 94 (1999).

19 Peterson, C.A., and R.L. Calderon. Trends in enteric disease

as a cause of death in the United States, 1989-1996.

American Journal of Epidemiology 57: 58-65 (2003).

20 Centers for Disease Control. Shigellosis. 2001. (November

19, 2002; http://www.cdc.gov/ncidod/dbmd/diseaseinfo/

shigellosis_g.htm)

21 Centers for Disease Control. Escherichia coli O157:H7.

2001. (November 19, 2002;

http://www.cdc.gov/ncidod/dbmd/diseaseinfo/

escherichiacoli_g.htm).

22 Martin, J.A., B.E. Hamilton, S.J. Ventura, F. Menacker, and

M.M. Park. Births: Final data for 2000. National Vital Statistics

Report 50(5): 16, 79 (2002).

23 Hoyert, D.L. et al. Deaths: Final Data for 1999, 2001.

op. cit. 

Endnotes 

1 Centers for Disease Control and Prevention. Unrealized

Prevention Opportunities: Reducing the Health and Economic

Burden of Chronic Disease, Atlanta, GA: National Center for

Chronic Disease Prevention and Health Promotion, Chronic

Disease Prevention, November 1998.

2 Pastor, P.N., D.M. Makuc, C. Reuben, C., and H. Xia, et al.

Chartbook on Trends in the Health of Americans, Health, United

States, 2002, Hyattsville, MD: National Center for Health

Statistics, 2002. [Online Trend Data Available at:

http://www.cdc.gov/nchs/products/pubs/pubd/hus/02hustop.ht]

3 United Nations. Demographic Yearbook 1999, New York:

United Nations, 2001, 479-506. United Nations. 

4 Pastor, P.N., et al. Chartbook on Trends in the Health of

Americans Health, United States, 2002, 2002. op. cit.

5 Ibid.

6 Ibid.

7 Hoyert, D.L., E. Arias, B.L. Smith, S.L. Murphy, and K.D.

Kochanek. Deaths: Final Data for 1999. National Vital

Statistics Report 49: 6-9 (2001).

8 Ries, L.A.G., M.P. Eisner, C.L. Kosary, et al. (eds). SEER Cancer

Statistics Review, 1973-1998. Bethesda, MD: National Cancer

Institute, 2001.

9 Ibid.

10 Ibid.

11 Pastor, P.N., et al. Chartbook on Trends in the Health of

Americans Health, United States, 2002, 2002. op. cit.

12 Hoyert, D.L. et al. Deaths: Final Data for 1999, 2001.

op. cit.

Endnotes
Chapter 4 - Human Health

4-22

EPA’s Draft Report on the Environment 2003

24 U.S. Environmental Protection Agency. America's Children

and the Environment: Measures of Contaminants, Body Burdens,

and Illnesses (Second Edition), EPA 240-R-03-001.

Washington, DC: U.S. Environmental Protection Agency,

Office of Children's Health Protection, National Center for

Environmental Economics, Office of Policy, Economics and

Innovation, February 2003.

25 Ries, L.A.G. et al. SEER Cancer Statistics Review, 1973-1998,

2001. op. cit.

26 Anderson, R.N. Deaths: Leading causes for 1999. National

Vital Statistics Report 49 (11): 8 (2001).

27 Mannino, D.M. et al. Surveillance for asthma - United States,

1980-1999, 2002. op. cit.

28 U.S. Environmental Protection Agency. America's Children

and the Environment: Measures of Contaminants, Body Burdens,

and Illnesses (Second Edition), 2003. op. cit.

29 Akinbami, L.J. and K.C. Shoendorf. Trends in Childhood

Asthma: Prevalence, Health Care Utilization and Mortality.

Pediatrics. 110: 315-332 (2002).

30 National Academy of Sciences. Clearing the Air: Asthma and

Indoor Air Exposures, Washington DC: National Academies

Press, Committee on the Assessment of Asthma and Indoor

Air, Division of Health Promotion and Disease Prevention,

Institute of Medicine, 2000. 

31 Ibid. 

32 Centers for Disease Control. National Report on Human

Exposure to Environmental Chemicals. Atlanta, GA: March 2001.

33 U.S. Environmental Protection Agency. Air Quality Criteria

for Particulate Matter, Third External Review Draft, EPA 600-P99-002aC. Washington, DC: U.S. Environmental Protection

Agency, Office of Research and Development, National

Center for Environmental Assessment, April 2002.

34 U.S. Environmental Protection Agency. Air Quality Criteria

for Ozone and Related Photochemical Oxidant, EPA 600-P-93-

004aF-cF. Research Triangle Park, NC: U.S. Environmental

Protection Agency, Office of Research and Development,

National Center for Environmental Assessment, July 1996.

35 Hoyert, D.L. et al. Deaths: Final Data for 1999, 2001.

op. cit.

36 Martin et al. Births: Final Data for 2000, 2002. op. cit.

37 Friis, R.H., and T.A. Sellers, Epidemiology for Public Health

Practice (Second Edition), Gaithersburg, MD: Aspen Publishers,

Inc., 1999.

38 U.S. Environmental Protection Agency. Respiratory Health

Effects of Passive Smoking: Lung Cancer and Other Disorders,

EPA 600-6-90-006F. Washington, DC: U.S. Environmental

Protection Agency, Office of Research and Development,

Office of Air and Radiation, December 1992.

39 National Research Council. Measuring Lead Exposure in

Infants, Children, and Other Sensitive Populations, Washington

DC: National Academies Press, 1993.

40 U.S. Environmental Protection Agency. American's Children

and the Environment: Measures of Contaminants, Body Burdens

and Illnesses (Second Edition), 2003. op. cit. 

41 Centers for Disease Control and Prevention. Second

National Report on Human Exposure to Environmental Chemicals,

NCEH Publication No. 03-0022. Atlanta, GA, January 2003.

Endnotes
4-23

Chapter 4 - Human Health

EPA’s Draft Report on the Environment 2003

42 National Research Council. Measuring Lead Exposure in

Infants, Children, and Other Sensitive Populations, 1993. op. cit.

43 Dockery, D.W., and C.A. Pope. “Outdoor Air I: Particulates.”

In K. Steenland and D.A. Savitz (eds.), Topics in Environmental

Epidemiology. New York, NY: Oxford University Press, 1997. 

44 Nadakavukaren, A. Our Global Environment: A Health

Perspective (Fifth Edition), Prospect Heights, IL: Waveland

Press, Inc, 2000.

45 U.S. Environmental Protection Agency. Air Quality Criteria

for Carbon Monoxide, EPA 600-P-99-001F. Research Triangle

Park, NC: U.S. Environmental Protection Agency, Office

Research and Development, National Center for

Environmental Assessment. June 2000. 

46 U.S. Environmental Protection Agency. Air Quality Criteria

for Particulate Matter, Third External Review Draft, 2002. op.

cit.

47 Ibid.

48 Ibid. 

49 Ibid. 

50 McConnell, R., K. Berhane, F. Gilliland, S.J. London, T. Islam,

W. Gauderman, A. James, M. Edward, H.G. Margolis, and J.M.

Peters. Asthma in exercising children exposed to ozone: A

cohort study. The Lancet 359: 386-391 (2002).

51 U.S. Environmental Protection Agency. Air Quality Criteria

for Ozone and Related Photochemical Oxidants, EPA 600-P-93-

004aF-cF. Research Triangle Park, NC: U.S. Environmental

Protection Agency, Office of Research and Development,

National Center for Environmental Assessment. July 1996.

52 Ibid. 

53 Examples of personal monitoring include EPA's Total

Exposure Assessment Monitoring (TEAM) studies and its

National Human Exposure Assessment Survey (NHEXAS), and

the Relationship of Indoor, Outdoor and Personal Air (RIOPA)

study conducted by the Mickey Leland Center.

54 Centers for Disease Control and Prevention. Second

National Report on Human Exposure to Environmental Chemicals,

2003. op. cit.

55 Centers for Disease Control and Prevention. National

Report on Human Exposure to Environmental Chemicals, 2001.

op. cit. 

56 Centers for Disease Control and Prevention. Second

National Report on Human Exposure to Environmental Chemicals,

2003. op.cit. 

57 National Research Council. Toxicological Effects of

Methylmercury, Washington, DC: National Academy of

Sciences, 2000.

58 Centers for Disease Control and Prevention. Second

National Report on Human Exposure to Environmental Chemicals,

2003. op. cit.

59 National Research Council. Toxicological Effects of

Methylmercury, 2000. op. cit.

60 U.S. Environmental Protection Agency. American's Children

and the Environment: Measures of Contaminants, Body Burdens

and Illnesses (Second Edition), 2003. op. cit.

61 U.S. Environmental Protection Agency, National Center for

Environmental Assessment. Integrated Risk Information

System (IRIS) for Methylmercury (MeHg). July 27, 2001. (July

27, 2001; http://www.epa.gov/iris/subst/0073.htm).

Endnotes
Chapter 4 - Human Health

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EPA’s Draft Report on the Environment 2003

62 U.S. Environmental Protection Agency. America's Children

and the Environment: Measures of Contaminants, Body Burdens,

and Illnesses (Second Edition), 2003 op. cit.

63 Centers for Disease Control and Prevention. Second

National Report on Human Exposure to Environmental Chemicals,

2003. op. cit.

64 Ibid.

65 Centers for Disease Control and Prevention. Second

National Report on Human Exposure to Environmental Chemicals,

2003. op. cit.

66 U.S. Environmental Protection Agency. Air Quality Criteria

for Particulate Matter, Third External Review Draft, 2002. op.

cit.

67 Centers for Disease Control and Prevention. Human

Exposure to Exposure to Environmental Chemicals, 2001. op. cit.

68 Centers for Disease Control and Prevention. Second

National Report on Human Exposure to Environmental Chemicals,

2003. op. cit.

69 Ibid.

Endnotes
5-1

Chapter 5 - 

Ecological Condition
Chapter 5 - Ecological Condition

5-2

EPA’s Draft Report on the Environment 2003

Introduction

Introduction

Air, water, land—these are elements of “the environment” that the Environmental Protection Agency

(EPA) seeks to protect. But assessing the state of the

environment requires looking at a bigger picture. Air, water,

and land are connected by natural cycles. For example, nitrogen-laden topsoil eroded from the Midwest may travel down

the Mississippi River and pollute the Gulf of Mexico, or chemicals released to the air in the Great Lakes region may find

their way into the waters in the Northeast. Living things

inhabit virtually all of the nation’s air, water, and land and are

affected by innumerable natural and human events. 

How can researchers, managers, policymakers, and the public track this big picture?

One forward-looking way is to link the state

of the nation’s air, water, land, and living

organisms into a broad framework termed

“ecological condition”—the sum total of

the physical, chemical, and biological components of ecosystems and how they interact. Ecological condition is ever changing,

multifaceted, and specific to place and

ecosystem. Understanding ecological condition is crucial because humans depend on,

and are responsible for, the nation’s ecosystems—forests, grasslands, shrublands, farmlands, urban and suburban environments,

fresh waters, and coasts and oceans. These

systems provide food, fiber, and shelter, as

well as “housekeeping” functions ranging

from water filtration and crop pollination to

waste decomposition and recycling.

Trends in ecological condition, like disease

trends described in Chapter 4 – Human

Health, reflect the outcome of many different events and activities, both natural and

human induced. Ecosystem condition is the

result of natural resource management at

national and state levels, local zoning and

land use decisions, pollution and pollution prevention activities, natural disturbances, and many other factors. EPA is one

of many federal, state, tribal, and local government and private partners working to understand ecological condition and

to protect the nation’s ecosystems. Most EPA programs focus

on managing environmental stressors, such as minimizing

chemicals in air and water or reducing toxic substances and

hazardous waste. Measuring ecological condition will help EPA

systematically assess how its management of stressors affects

overall ecosystem health.

This chapter is organized around the

framework of six essential ecological

attributes developed by EPA’s Science

Advisory Board (SAB) (Exhibit 5-1): landscape condition, biotic condition, chemical and physical characteristics, ecological

processes, hydrology and geomorphology,

and natural disturbance regimes. Within

each of these areas, indicators have been

defined for each of the six ecosystem or

land cover types identified by the H. John

Heinz Center for Science Economics, and

the Environment (Exhibit 5-2). The

Technical Document for this EPA report

describes each of these indicators, including the available data, data limitations, and

data sources.1

This chapter describes some of these indicators, including indicators for which

national data are available and others for

which national data are limited. In addition, the chapter illustrates some examples

of promising approaches for using ecological condition to evaluate environmental

protection efforts. The chapter closes by

summarizing both the state of data for

assessing ecological condition and key

challenges.

Chapter 5: Ecological Condition

Landscape Condition

Biotic Condition

Chemical and Physical

Characteristics

Hydrology and

Geomorphology

Natural Disturbance

Regimes

Ecological Condition as an 

Environmental Result

Challenges in Developing 

Ecological Condition 

Indicators 

Ecological Processes
5-3

Chapter 5 - Ecological Condition

EPA’s Draft Report on the Environment 2003

Introduction

Recent Ecological Condition Research Efforts

The chapter presents initial work toward identifying indicators to help answer the question, “What is the ecological condition of the United States?”

This work draws primarily on two previous research efforts:

■ “Framework for Assessing and Reporting on Ecological Condition”2 developed by EPA’s Science Advisory Board (SAB). The SAB Framework designates “essential ecological attributes” (Exhibit 5-1) that provide a means to examine ecological condition as well as to consider the effects of stressors on condition.

■ “The State of the Nation’s Ecosystems: Measuring the Lands, Waters, and Living Resources of the United States,”3 a nationwide effort of government and the private sector led by The H. John Heinz III Center for Science, Economics and the Environment (The Heinz Center). Many of the indicators in this chapter and in the Technical Document accompanying this report are derived from the Heinz report.

Exhibit 5-1: EPA Science Advisory Board essential ecological attributes

Source: EPA, Science Advisory Board. Framework for Assessing and Reporting on Ecological Condition. June 2002.

Essential Ecological Attribute Description Example Indicators

Ecological Processes Metabolic function of ecosystems - energy 

flow, element cycling, and the production, 

consumption, and decomposition of organic 

matter.

Primary productivity

Movement of nitrogen

Chemical and Physical 

Characteristics

Physical parameters (e.g., temperature) and 

concentrations of chemical substances 

(e.g., nitrogen) present in the environment.

Nitrate, phosphate, and other 

chemical levels in streams

Biotic Condition The condition or viability of communities, 

populations, and individual biota.

Imperiled species in the U.S.

At-risk native species

Trends in invasive and non-invasive 

birds in grasslands and shrublands

Hydrology and Geomorphology The interplay of water flow and land forms. Soil erosion

Change in stream flow rates

Natural Disturbance Regimes The historical function of discrete and 

recurrent disturbances that shape 

ecosystems.

Forest disturbances: fire, insects, 

and disease

Landscape Condition The extent, composition, and pattern of 

habitats in a landscape.

Status and change in extent of 

ecosystems
Chapter 5 - Ecological Condition

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EPA’s Draft Report on the Environment 2003

Introduction

What is the ecological condition

of the United States?

Basic questions about the health of the nation’s ecosystems

and the overall ecological condition of the U.S. have proven

difficult to answer in a few summary statements. Ecosystems

are dynamic assemblages of organisms that change and adapt

continuously to a variety of natural disturbances and stressors, such as fires and floods, as well as to pollutants and land

use changes. A variety of ecosystem management practices

are used to support human survival and economic growth.

Because of these complexities, measuring ecological condition goes beyond monitoring air or water to determine

whether pollutant concentrations or temperatures exceed a

legal standard. Trying to characterize overall condition by

looking at only one factor, such as stressors, is like the blindfolded men trying to describe an elephant after touching only

one part of the animal. In the same way, we cannot determine

the overall condition of an ecosystem by looking at isolated

environmental measures, such as insect outbreaks in a forest,

chemical concentrations in water, or declines in the number of

certain species. Assessments of ecological condition must

incorporate measures of different characteristics, potentially

at different times and different places within a system. The

importance of multidimensional measurements to understand

multidimensional systems is described in more detail in

“Ecological Condition as an Environmental Result” later in this

chapter. This section illustrates indicators that provide

insights into the six attributes identified by the Science

Advisory Board. 

Forest Lands

Grasslands and Shrublands

Farmlands

Urban and Suburban 

Fresh Waters

Coasts and Oceans

Exhibit 5-2: Ecosystem types as described by The Heinz Center

Lands at least 10 percent covered by trees of any size, at least 1 acre in extent.

Lands used for production of annual and perennial crops and livestock and areas on the larger farm landscape (e.g., 

field borders and windbreaks, small woodlots, grasslands and shrubland areas, wetlands, farmsteads, small villages and 

other built-up areas) within or adjacent to croplands.

Places where the land is primarily devoted to buildings, houses, roads, concrete, grassy lawns, and other elements of 

human use and construction.

Lands in which the dominant vegetation is grasses and other non-woody vegetation or where shrubs (with or without 

scattered trees) are the norm. This ecosystem type includes bare rock deserts, alpine meadows, and arctic tundra.

Rivers and streams, including those that flow part of the year; lakes, ponds, and reservoirs; ground water; fresh water 

wetlands, vegetated margins of streams and rivers (riparian areas).

Estuaries and ocean waters under U.S. jurisdiction Estuaries are partially enclosed bodies of water (including bays, 

sounds, lagoons, and fjords) considered to begin at the upper end of tidal or saltwater influence and end where they 

meet the ocean.

Source: The Heinz Center. The State of the Nation's Ecosystems. 2002.

Ecosystem Type Description
5-5

Chapter 5 - Ecological Condition

EPA’s Draft Report on the Environment 2003

Landscape Condition

to other uses between the

mid-1950s and mid-1990s.11

For coral reefs, shellfish beds,

and submerged aquatic vegetation, baseline information

is inadequate, although a

survey in Chesapeake Bay

indicated that acres of submerged aquatic vegetation

have increased from 41,000

to 69,000 since 1978.12 The

structure and pattern of

estuarine landscapes, and their contribution to ecological

condition, remain inadequately measured or understood.

The changes in ecosystem acreages described above may represent a small percentage of a specific cover type on a

national basis. In some cases, however, even small changes can

have direct effects on species associated with ecosystems

locally. NatureServe, a non-profit organization that tracks

species diversity and loss nationwide, has stated that loss of

habitats due to changes in extent of land cover constitutes

the single greatest threat to species survival.13

As land use and acreage change, the mix of living things and

ecosystem types also change, with uncertain ripple effects.

Wetland ecosystems, for example, are critical to the life cycles

of plants, fish, shellfish, migratory birds, and other wildlife.

More than one-third of threatened and endangered species in

the U.S. live only in wetlands, and nearly half use wetlands at

some point in their lives.14 Forested wetlands often become

shrub wetlands after the trees are removed, and these two

types of ecosystems do not support the same plants and animals. Over the last 50 years, the amount of non-stocked forest has decreased, while the amount of forest with older trees

has increased.15 (For more information on these effects, see

Chapter 2 – Purer Water and Chapter 3 – Better Protected

Land.)

L

andscape condition, a term that applies to both terrestrial and aquatic ecosystems, includes such aspects of

ecosystems as extent, age, composition, and juxtaposition with other land cover types and land uses. Landscape

condition determines, in part, the ability of ecosystems to

sustain themselves, as well as respond to human needs—for

example, to supply crops and timber, fish and shellfish, clean

water and air, and wildlife nurseries. This section focuses on

one aspect of landscape condition—extent. Indicators

addressing age, composition, and patterns of ecosystems are

described in the accompanying Technical Document.

Extent provides basic information on how much of an ecosystem exists, where it is, and whether it is shrinking or expanding. Changes in the extent of various cover types in the U.S.

have been driven primarily by human land (and water) uses

over the past 400 years (Exhibit 5-3). As of 1997, approximately 25 percent of forests, 3 to12 percent of grasslands

and shrublands, and more than 50 percent of wetlands, had

been converted to other uses since European settlement.4,5,6

Most of the changes in ecosystem acreage since the 1980s

have stemmed from agriculture and development activities.

Between 1982 and 1997, approximately 7 million acres of

agricultural land and 10 million acres of forest land were converted to residential, transportation, industrial, urban, and

other uses.7 Another 22 million acres of pasture and rangeland (including some grasslands and shrublands) were converted to crop production.8

Only limited information exists on the total extent of water

ecosystems, both fresh water and coastal, other than wetlands. Small streams may disappear because of mining,

damming, or water withdrawals. However, because there is no

widely accepted way to classify streams for ecological monitoring, no national dataset exists for reporting on their gains

or losses.9 The extent and composition of most, but not all,

of the nation’s coastlines have been established by the

National Oceanic and Atmospheric Administration.10 Eight

percent or 400,000 acres of coastal wetlands were converted

Landscape

Condition

Indicators

Extent of ecosystem/land cover

types (forests, farmlands,

urban/suburban, grasslands/shrublands, fresh waters, coasts and

oceans)

Landscape Condition
Chapter 5 - Ecological Condition

5-6

EPA’s Draft Report on the Environment 2003

Exhibit 5-3: Historical and current extent of land cover classes

Note: All estimates are in acres.

a Does not include Alaska. 

b USDA, Forest Service. U.S. Forest Facts and Historical Trends. April, 2001 and USDA, Forest Service. Draft Resource Planning Act Assessment Tables. May 3, 2002 (updated 

 August 12, 2002). (September 2003; http://www.ncrs.fs.fed.us/4801/FIADB/rpa_tabler/Draft_RPA_2002_Forest_Resource_Tables.pdf

c Klopatek, J.M., et al. Land use conflicts with natural vegetation in the United States. 1979.

d The Heinz Center. The State of the Nation's Ecosystems. 2002.

e USDA, Natural Resources Conservation Service. Summary Report: 1997 National Resources Inventory (revised December 2000). 2000.

f USDA, Natural Resources Conservation Service. National Resources Inventory: Highlights. 2001.

g Environment Canada and EPA. The Great Lakes, an Environmental Atlas and Resource Book. 1995.

h Dahl, T.E. Status and Trends of Wetlands in the Conterminous United States: 1986 to 1997. U.S. Fish and Wildlife Service. 2000.

i Dahl, T.E. Wetlands Losses in the United States 1780's to 1980's. 1990.

j EPA, Office of Water. The Quality of Our Nation's Waters, A Summary of the National Water Quality Inventory: 1998 Report to Congress. 2000.

Forest Lands 1 billion 744 million 749 million

Farmlands (Acreage Shown is 553 million 530 million

for Croplands and 

Pasturelands)

900 million - 1 billion 872 million (based on loss of 11 

million acres of non-federal)d, e

Grasslands and 861 million (an additional 205 million in Alaska)

Shrublands

Urban and Suburban (Acreage 73 million 98 million

Shown is for Developed 

Lands)

41.6 million acres of lakes, ponds, and streams

60.2 millions acres - Great Lakes

3.7 million miles of streams and riversa, g

Fresh Waters

Wetlands 221 million 106.1 million 105.5 million (Alaska: 170 million acres)

57.9 million acres of estuarine surface area

66,645 miles of coastline

Coasts and Oceans

Land Cover Class

Pre-European

Acreage Estimate

1977-1982

Acreage Estimate

1997-2002

Acreage Estimate

No data No data

No data No data

Landscape Condition
5-7

Chapter 5 - Ecological Condition

EPA’s Draft Report on the Environment 2003

Biotic Condition

Biotic Condition

ecosystems. Additionally,

data on forest lands in 37

states provide a partial view

of tree condition as an indicator of biotic condition. This

section summarizes the data

available for these measures

of biotic condition.

Roughly 200,000 native

plant, animal, and microbial

species inhabit the U.S.16

NatureServe is tracking approximately 16,000 native plant

and 6,000 native animal species. Of these, about 19 percent

of the animal and 15 percent of the plant species are estimated to be imperiled or critically imperiled, as shown in Exhibit

5-4.17 (Note that the ranking criteria, evidence requirements,

taxonomic coverage, and purposes for gathering this information vary from those of the Endangered Species Act, and thus

the categories do not match official “threatened and endangered” species listings.18) Increased risk levels for a particular

species may be due to historical or recent population

declines or may reflect natural rarity.19

Imperiled species have been examined by ecosystem. Fresh

water species show the highest rates of imperilment (Exhibit

5-5).20 One percent of plants and 3 percent of animals may

already be extinct.21

Birds, which are highly mobile (and “monitored” by many

people for pleasure), respond quickly to environmental

change. Changes in the mix of native and alien—and invasive

and non-invasive—birds often signal changes in grassland

and shrubland condition. The presence of native non-invasive

species generally reflects relatively intact, high-quality native

grasslands and shrublands. Conversely, increases in both

native and non-native invasive species, such as American

crows or European starlings, often accompany land conversion to agriculture or grazing uses, landscape fragmentation

due to suburban and rural development, and the spread of

E

very ecosystem contains living components; their very

presence or absence, along with their diversity, signals

the capacity of a place to support life. Because living

organisms respond to multiple factors, their condition—

known as biotic condition—provides a snapshot of many

other conditions within their environment. Thus, indicators of

biotic condition, such as species at risk, competition from

non-native species, or rates of disease and deformity, are vital

to assessing ecological condition. 

Currently, the data to support such indicators are limited, and

no data are available to accurately measure biotic condition

on a national basis. Data do exist on a small fraction of the

total number of native species in the U.S. and on the presence of “invasive” bird species in grassland and shrubland

Biotic Condition

Indicators

At-risk native species

Benthic Community Index

Population trends of invasive and

native non-invasive bird species

Tree condition

Exhibit 5-4: At-risk land and fresh water 

plant and animal native species, 2000 Percent of all species

0

5

10

15

20

25

30

35

Land and Fresh Water Plants Land and Fresh Water Animals

Coverage: all 50 states.

Source: The Heinz Center. The State of the Nation's Ecosystems. 2002.

Data from NatureServe and its Natural Heritage member programs.

Extinct

Critically Imperiled

Imperiled

Vulnerable

All At-Risk
Chapter 5 - Ecological Condition

5-8

EPA’s Draft Report on the Environment 2003

exotic vegetation.22 From the mid-1960s until the last halfdecade, invasive and non-invasive bird species changed in

similar proportions in grasslands and shrublands. From 1996

to 2000, however, the population of birds representing invasive species climbed steeply.23 This increase might represent

a short-term fluctuation in bird populations, or it could signal

changes in grassland and shrubland ecosystem condition.

The health and physiology of individual organisms are also

signs of ecosystem condition. In an assessment of forest condition, for example, data from the U.S. Department of

Agriculture (USDA) Forest Service Forest Health Monitoring

Program (currently available for only 37 states) examined the

number of dead or dying trees, the number of forests with

thin canopies, and the extent to which buildup of flammable

material threatened to alter the ecosystem significantly.

Although the data are insufficient to assess 39 percent of

forested areas, analyses show that nearly 41 percent of sampled trees were in fair or good condition and 20 percent were

in poor condition.24

Biotic Condition

Exhibit 5-5: Percent of imperiled species by ecosystem, 2000

Source: Based on the Heinz Center. The State of the Nation's Ecosystems. 2002. Data from NatureServe and its Natural Heritage member programs.

Forest Lands

Grasslands and Shrublands

Farmlands

Urban and Suburban Ecosystems

Fresh Water Ecosystems

Coasts and Oceans

All U.S.

 1700

 1700

 4000

5%

6%

8%

15% of plants and 19% of animals

3.5%

3.5%

13%

1.5%

0.5%

4%

1% of plants and 3% 

of animals

Land Cover Class Number of Animal 

Species Percentage 

Imperiled Species

Percentage Critically 

Imperiled Species

cen age 

Presumed/Possibly 

Extinct

22,000 plant and 

animal species
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Chapter 5 - Ecological Condition

EPA’s Draft Report on the Environment 2003

Chemical and Physical Characteristics

Chemical and Physical Characteristics

exceeding drinking water

standards (Exhibit 5-6).26

The NAWQA program provides consistent and comparable information on nutrient

and pesticide concentrations

in streams in agricultural

areas, although the network

design and number of sites

do not allow estimates to be

made for agricultural streams nationally. Nitrate loss from

most forests does not appear to be resulting in high-nitrate

concentrations in forest streams, but few streams are sampled

in parts of the country where nitrate deposition tends to be

high (e.g., eastern states).

A number of physical and chemical indicators are being monitored in Atlantic and Gulf Coast estuaries to help diagnose

and interpret information on biotic condition. Eighteen percent of mid-Atlantic estuaries show high nitrogen concentrations, and 12 percent show high phosphorus concentrations.

Twenty percent of Atlantic and Gulf Coast estuaries have low

dissolved oxygen concentrations (i.e., less than 5 milligrams

per liter). On average, 75 percent of the sediments contain

elevated pesticide concentrations, and 40 percent show elevated concentrations of heavy metals.27

Chemical and physical properties, like other non-living

ecosystem attributes, help shape the environment of

living things. Many of EPA’s specific environmental

protection responsibilities include measuring and addressing

chemical changes. Chemical measurements are often based on

water sampling for, among other substances, nitrogen and

phosphorus compounds, dissolved oxygen, pesticides, and

heavy metals. 

Some data on chemical characteristics in U.S. waters have

been collected by the U.S. Geological Survey National Water

Quality Assessment (NAWQA) program. In an analysis done

for the Heinz report, NAWQA reported on contaminants in

stream waters from 109 sites and in sediments from 558

stream sites in 36 watersheds across the U.S. At least half of

monitored streams had contaminant concentrations that

exceed water quality criteria for wildlife.25 However, no analyses yet relate these concentrations to the status of fish or

invertebrate communities in the streams. Nitrate levels were

highest in farmland streams, with 10 percent of the samples

Chemical and

Physical

Characteristics

Indicators

Nitrate levels in streams 

by ecosystems

Source: USGS, National Water Quality Assessment. The Quality of Our Nation's 

Waters–Nutrients and Pesticides. 1999.

Land Cover 

Class Nitrate Levels

Number of 

Streams Sampled

Forests 

Grasslands and 

Shrublands

Farmlands

Urban and 

Suburban 

Ecosystems

36

No data 

50

21

50% < 0.1 mg/L 

75% < 0.5 mg/L 

3% > 1.0 mg/L (1 sample)

No data 

50% < 2.0 mg/L 

10% > 10 mg/L (exceeds 

 drinking water standard)

40% > 1.0 mg/L 

25% < 0.5 mg/L 

3% < 0.1 mg/L

Exhibit 5-6: Nitrate levels in streams by ecosystem, 

1992 - 1998
Chapter 5 - Ecological Condition

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EPA’s Draft Report on the Environment 2003

Ecological Processes

E

cological processes comprise the cycling of chemicals

and energy through ecosystems. Like the flow of raw

materials and labor through a factory, these processes

keep ecological systems running. Ecosystems are solar powered: plants turn energy from the sun, carbon dioxide from

the air, and nutrients from the soil into food for other organisms. Water and nutrients such as carbon and nitrogen—

fundamental building blocks of living tissue—also cycle

continuously through ecosystems. Changes in nutrient cycles

or disruption in water cycles not only affect the operation of

an ecosystem locally, but also may reach well beyond ecosystem boundaries.

The amount of solar energy captured by plants is a key indicator of ecosystem function.28,29 The energy brought into an

ecosystem is a key factor in determining the amount of photosynthesis, and the amount of plant growth that occurs each

year.30 Plant growth may increase under plant-friendly conditions, for instance, when rainfall or nutrients increase, or it

may decrease under stressful conditions, as in the presence

of toxic substances or disease. Changing growth affects, and

additionally may change, the way ecosystems function, altering yields of crops and timber, and the diversity and mix of

animal and other species.

For the 11-year period between 1988 and 2000, annual estimates of plant growth reveal no overall trend for any land

cover type or any region of the U.S., although they do fluctuate year to year by as much as 40 percent of the 11-year

average.31 Long-term monitoring will be required to separate

consistent trends from year-to-year variability caused by rainfall and other factors. No estimates yet exist for phytoplankton or submerged vegetation in fresh water or coastal

systems.

Nitrogen is a critical element for plant growth and a basic

constituent of proteins. In excess, however, it can make soil

conditions less favorable for plant growth, damage aquatic

life, and impair human health. Although nitrogen gas makes

up nearly 80 percent of Earth’s atmosphere, organisms cannot use it until it is converted to active forms by nitrogen-fixing bacteria, fertilizer

production, or fossil fuel

combustion. Over the past

century, the forms of nitrogen traveling through air,

water, and soil have changed

dramatically, leading to

ecosystem effects.32 Nitrogen compounds falling in rain acidify soils and surface waters and can stimulate heavy growths

of algae, which may take up so much oxygen that few other

organisms survive. Nitrogen compounds can leach into and

contaminate ground water used for drinking and have harmful

effects in surface water systems. Movement of excess nitrogen

from agricultural sources in the upper Mississippi River basin,

for example, has been correlated with high levels of plant productivity (eutrophication) and a lack of oxygen (hypoxia)

more than 1,000 miles downstream in the northern Gulf of

Mexico.33 The lack of oxygen kills fish, shrimp, and bottomdwelling communities, causing economic losses to commercial

fisheries and diminishing regional biodiversity.

Biologically active forms of nitrogen enter the air as pollutants from industrial facilities, cars, and feedlots and then

pass into ecosystems via plants, soils, and water bodies.

Nitrogen from septic tanks, animal waste, and excess fertilizer

also leaches into the soil and ground water or runs off the

land, moving through streams, rivers, and lakes until it eventually reaches estuaries. Some enters streams directly from

wastewater treatment plants, and some is lost again to the

atmosphere as it moves downstream. The yield of nitrogen in

runoff varies in different parts of the country, reflecting differences in atmospheric deposition, fertilizer use, population

density, and ecosystem characteristics. An analysis of estimated nitrogen yield shows that watersheds in the upper

Midwest and Northeast experience between 4.7 and 15.6

pounds of nitrogen in runoff per acre per year, but watersheds in the mountains of the West yield less than 10 percent of that amount (Exhibit 5-7).34

Ecological Processes

Indicators

Terrestrial Plant Growth Index 

Movement of nitrogen

Ecological Processes
5-11

Chapter 5 - Ecological Condition

EPA’s Draft Report on the Environment 2003

Ecological Processes

The yield of nitrogen from major watersheds is characterized

as pounds of nitrogen per acre of watershed area that enters

rivers and streams through discharges, runoff, and other

sources. The load of nitrate, a common form of nitrogen, from

major rivers is defined as the tons of nitrate carried to the

ocean each year by the four largest U.S. rivers.35

Nitrate load in the Mississippi River has been monitored since

the mid-1950s and from the Susquehanna, St. Lawrence, and

Columbia rivers since the 1970s. The Mississippi drains the

nation’s midwestern breadbasket, where fertilizer use and soil

erosion are often high. Although fluctuating from year to year,

the Mississippi’s nitrate load has increased from approximately 250,000 tons per year in the early 1960s to approximately 1 million tons per year during the 1980s and 1990s

(Exhibit 5-8).36 Nitrate loads in the other three rivers have

oscillated around 50,000 tons per year since the 1970s,

although the Columbia River spiked to 100,000 tons per

year in the late 1990s.37

Coverage: selected areas of lower 48 states. 

Source: The Heinz Center. The State of the Nation's Ecosystems. 2002. Data from three

U.S. Geological Survey efforts: the National Stream Quality Network, the National

Water Quality Assesment, and the Federal-State Cooperative Program.

Total Nitrogen (pounds of nitrogen per acre per year)

Data Not Available

Less than .02

.02–0.9

0.9–2.3

2.3–4.7

4.7–15.6

Exhibit 5-7: Yield of total nitrogen from 

major watersheds, 1996–1999 Nitrate Load (thousand tons N/year)

Mississippi

Susquehanna

St. Lawrence

Columbia

Detail

0

500

1000

1500

2000

2500

1950 1960 1970 1980 1990 2000

0

50

100

1970 1980 1990 2000

Exhibit 5-8: Nitrate load carried by major rivers, 

1950s–2000

Coverage: selected major rivers. 

Source: The Heinz Center. The State of the Nation's Ecosystems. 2002. Data from 

three U.S. Geological Survey efforts: the National Stream Quality Network, the 

National Water Quality Assessment, and Federal–State Cooperative Program.
Chapter 5 - Ecological Condition

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EPA’s Draft Report on the Environment 2003

Hydrology and Geomorphology

Hydrology and Geomorphology

L

ike the framing of a house, the properties, distribution,

and circulation of water (hydrology) and the relief features of the earth’s surface (geomorphology) help give

environments their character. The quantity and timing of

water flows influence many ecosystem parts and processes,

including those with direct effects on human activities. Loss

of topsoil, which can take millennia to replenish, has obvious

implications for agriculture, and moving sediment can cause

sedimentation in harbors and other facilities and can carry

chemicals for long distances.

High and low water flows have important implications for

ecosystem health. Low water flows define the smallest area

available to stream biota during the year, and high flows

shape stream channels and wash out silt and debris. Some

fish depend on high flows for spawning. The timing of high

and low flows affects the status of aquatic species as well as

human water supplies and the flooding of farms, towns, and

cities. Climate, dams, water withdrawals, and changes in land

use all affect the flow of water.

High and low flows for 867 streams and rivers with appropriate data (records between 1930 and 1949, and during the

1970s, 1980s, and 1990s) show little change from the 1970s

to the 1990s.38 The same is true for the timing of high and

low flows. However, the number of streams with high flows

well above their historic (1930 to 1949) rates rose markedly

from the 1980s to the 1990s.39 This increase may be attributable, in part, to earlier droughts, but may also be linked to

widespread changes in land use.

Erosion can also have significant effects on ecosystem condition. Wind and water erode soils naturally, changing the

character of the landscape. Human activities such as development, road construction, timber harvesting, and agricultural

practices that disturb the soil surface or remove anchoring

vegetation increase the

potential for erosion. Soil

loss not only reduces soil

quantity and quality but can

degrade water quality by

carrying nutrients, pesticides, and other contaminants downstream.

Sedimentation can raise

costs to maintain reservoirs,

navigation channels, and water treatment plants and can

degrade habitat for aquatic organisms.

Reductions in erosion can occur through improved tilling or

management practices, removal of marginal land from production, and land conservation efforts like the Conservation

Reserve Program (CRP). Reducing erosion contributes not

only to improved soil quality but also to improved water quality in adjacent and downstream aquatic ecosystems.

Data on the 409 million acres of croplands and CRP lands

show that erosion from water and wind decreased from a total

of more than 3 billion tons per year in 1982 to about 1.9 billion tons in 1997.40 (Not all of this soil actually moved offsite.) The croplands and CRP lands experiencing erosion in

1997 are shown in Exhibit 5-9. About 15 percent of U.S.

cropland and CRP land is estimated to have a high potential

for wind erosion, based on an analysis of several factors

including soil properties, landscape characteristics (e.g., vegetative cover, rainfall), and management practices (e.g., wind

barriers, terracing). This represents a decrease in acreage of

almost 33 percent between 1982 and 1997.41 The acreage

with the highest potential for water erosion, based on similar

factors, also decreased by about 33 percent to 89 million

acres. This represents about 22 percent of U.S. cropland.42

Hydrology and

Geomorphology

Indicators

Changing stream flows

Soil erosion
5-13

Chapter 5 - Ecological Condition

EPA’s Draft Report on the Environment 2003

Hydrology and Geomorphology

Exhibit 5-9: Wind and water erosion on croplands and Conservation Reserve Program (CRP) lands, 1997

Puerto Rico/U.S. Virgin Islands

Hawaii

Note: Alaska is not covered by the National Resources Inventory.

Source: USDA, Natural Resources Conservation Service. National Resources Inventory, 1997, revised December 2000: Total Wind and Water Erosion, 1997.

December 5, 2000 (April 11, 2003; http://www.nrcs.usda.gov/technical/land/meta/m5112.html

Each blue dot 

represents 200,000 

tons of erosion due to 

water: 1,068 million 

tons per year.

Each red dot represents 

200,000 tons of 

erosion due to wind. 

840 million tons per 

year: Total 1.9 billion 

tons per year.

Sheet and rill (water) erosion mostly 

occurs in areas east of the Corn Belt 

and Southern Plains. Wind erosion is 

mostly in the West, Northern Plains, 

Southern Plains, and parts of the Corn 

Belt. Several parts of the country battle 

difficult problems with both wind and 

water erosion.

Alaska 
Chapter 5 - Ecological Condition

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EPA’s Draft Report on the Environment 2003

Natural Disturbance Regimes

Natural Disturbance Regimes

events, fire frequency, and

insect and disease outbreaks. Several recent events

proved to be outside the

range of natural disturbance

patterns in the 1979 to

1995 timeframe, including:

■ El Niño from 1997 to

2000.

■ Northeast ice storm in 1998.

■ Spruce beetle outbreak in 1996, Spruce budworm outbreak

in 1997, and a Southern Pine beetle outbreak in 2000.

■ National acres burned in 2000 and the area burned in the

West in 1996, 1998, and 2000.43

Disturbance regimes can be changed by resource management. For example, in the two decades between 1980 and

1999, wildfires burned between 2 million and 7 million acres

annually, down from a high of 52 million acres in 1930.44 The

decline is primarily due to fire suppression policies.45

Wildfires in 2000, however, reached 8.4 million acres.46

Disturbance and change, particularly over long periods

of time, are part of all ecosystems. Natural disturbances, from ice ages to droughts, can alter ecosystem

characteristics. Some attributes of ecosystems depend on various types of disturbances—for example, some coniferous

species depend on fire to open cones and clear ground cover

for germination and growth of native species. 

Understanding the roles that natural disturbances play in the

evolution of ecosystems is key to determining how land use

and management practices can improve ecosystem conditions. For example, an unprecedented epidemic of Southern

Pine beetle currently is damaging many forests in the southeastern U.S. Understanding this pest and its disturbance patterns can assist in developing appropriate responses to

restore ecological balance. The extensive acreages burned

from wildfires in the western U.S. in recent years pose similar

forest ecosystem challenges and opportunities for developing

appropriate responses. 

There have been few attempts to document regional or

national natural disturbance regimes as indicators. The USDA

Forest Service Forest Health Monitoring Program is an exception. Statistical data from the forest inventories conducted

between 1979 and 1995 have been used to establish shortterm baselines for natural disturbances such as climatic

Natural Disturbance

Indicators

Forest disturbances: 

fire, insects, and disease
5-15

Chapter 5 - Ecological Condition

EPA’s Draft Report on the Environment 2003

Ecological Condition as an Environmental Result

Ecological Condition as an Environmental Result

E

cological condition, like human health, is a crucial measure of the results of environmental protection activities.

As a regulatory agency, EPA has long monitored environmental stressors, as described in the chapters of this report

on air, water, and land. However, as discussed earlier in this

chapter, stressors alone are not good proxies for understanding the condition of an entire ecosystem. One might compare

measuring ecosystem health to measuring the health of the

economy. Economic indices such as the consumer price index

integrate multiple indicators—prices of many consumer

goods. Information on only one consumer product or one

sector would not be enough to judge trends in national pricing or spending. Similarly, monitoring only stressors, rather

than the living things that are stressed, or monitoring ecosystem attributes in isolation does not convey a full and accurate

picture of ecological condition. Using ecological condition as

an environmental result requires understanding the relationships between ecological condition (as described by the

SAB’s essential ecological attributes) and stressors that represent the focus of EPA’s current responsibilities for environmental stewardship. EPA can build on decades of monitoring

stressors while it develops and monitors appropriately multidimensional and better-linked ecological condition indicators.

Some promising approaches to identifying such indicators are

described below.

Many factors stress ecosystems. How ecosystems are affected

varies significantly according to the nature of the stress, its

duration and frequency, and the conditions in the ecosystem

before the stress occurred. For instance, the flows and interactions related to sulfur and nitrogen oxides as air pollutants

depicted in Exhibit 5-10 provide an example of the effects of

stress in ecosystems. Arrows depict sulfur and nitrogen in different forms as they move through a watershed. Any of the

components in Exhibit 5-10 could be measured as an indicator, but each alone contributes only a piece to the underExhibit 5-10: Interaction among ecological variables

Sulfur and nitrogen oxides 

from power plants and cars

Sulfur and nitrogen oxides 

concentrations in air Acidity of rain and snow

Amount of acid and sulfur 

in watersheds

Acidity of soil

Acidity of lakes and 

streams

Forest 

productivity

Tree

growth

Water 

 quality

Health of 

fish
Chapter 5 - Ecological Condition

5-16

EPA’s Draft Report on the Environment 2003

Ecological Condition as an Environmental Result

standing ecological condition. Monitoring the concentrations

of pollutants at various points in the flow can contribute to

understanding the effectiveness of pollution control programs. The success of a sulfur reduction program, however,

can be assessed only by tracking whether lower sulfur emissions actually lessen sulfur concentrations in air, water, soil,

fish, and forests. 

Using this type of integrated approach, EPA and its partners

were able to confirm that, following emissions reductions

required by regulations under the 1990 Clean Air Act

Amendments, acid rain decreased by 40 percent across broad

areas of the northeastern and upper midwestern U.S. in the

1990s.47 The decrease in acid rain itself was accompanied by

significant reductions in the number of ecosystems affected

by acid deposition.48 Moreover, continuing regional lake and

stream sampling has shown that in the Northeast, Upper

Midwest, and Appalachians, one-quarter to one-third of lakes

and streams previously affected by acid rain are no longer

acidic (although they are still sensitive to changes in acid

deposition).49

Just as important as measuring multiple variables is the choice

of what to measure. In the case of sulfur in the ecosystem,

measurements of emissions and conditions such as acidity of

soil or water are not enough. Those measures do not provide

any knowledge of the outcomes—the growth of trees or the

health of fish. These biotic components are critical pieces in

understanding the ecological condition of the system. 

One approach that addresses the need to measure critical

multiple variables is the index of biotic integrity (IBI), which

has been applied with fish, bottom-dwelling invertebrates, and

diatoms.50 Just as the consumer price index combines the

price of many consumer goods, the IBI combines measurements of a number of biological attributes, called “metrics,”

that reflect the ecological condition of a place, including biological diversity; relative abundance of indicator groups of

organisms, such as predators, highly tolerant species, or nonnative species; the health of individual organisms; and ecological relationships such as food web structure.51

In a demonstration project in mid-Atlantic streams, EPA

applied a fish IBI along with measurements of several prominent stressors. In a statistical sample of streams representing

90,000 total stream miles, IBI was used to evaluate the biological differences between minimally altered reference

streams in the region and streams with varied levels and types

of stressors. The study revealed that sought-after sport fish

declined in more turbid streams and in streams with increased

streamside agriculture.52 In addition, acidification lowered the

number of minnow, bottom-dwelling, and sensitive species but

raised the number of individuals belonging to non-native

species. Regionally, the results indicated that 27 percent of

the streams were in “good condition” relative to the reference

streams that represented the best current conditions in the

region (specifically, the IBIs of “good” streams ranked within

the top 25 percent of reference stream IBIs), 38 percent

were in “fair condition” (their IBIs ranked with the other 75

percent of reference streams), and 14 percent were in “poor

condition” (below the lowest 1 percent of reference stream

IBIs) (Exhibit 5-11).53

A macroinvertebrate IBI was also applied in the mid-Atlantic

streams demonstration project. Stream conditions were classified in much the same way as with the fish IBI. Based on the

macroinvertebrate IBI, 17 percent of the streams were in

“good condition” (within the top 25 percent of reference

stream IBIs), 57 percent were in “fair condition” (within the

lower 75 percent of reference stream IBIs), and 26 percent

were in poor condition (within the lowest 1 percent of reference stream IBIs) (Exhibit 5-11).54

These results are applicable regionwide, providing decisionmakers with a clearer picture of the ecological condition in

the region’s streams, a catalog of specific biological responses

associated with that condition, and insight about the effects

of specific stressors on condition. Collectively, this knowledge
5-17

Chapter 5 - Ecological Condition

EPA’s Draft Report on the Environment 2003

Ecological Condition as an Environmental Result

tells policymakers which stressors need to be managed to

protect or restore ecological condition.

In sum, using ecological condition as an outcome of environmental protection efforts will require monitoring strategies

that take into account both of the following:

■ The stressors—factors, activities, or variables—that create

or contribute to changes in ecological attributes (e.g.,

changes in biotic condition or ecological processes;

changes in habitat pattern and extent; physical, chemical,

and hydrologic changes; and changes in natural disturbance

regimes).

■ The actual outcomes of EPA’s efforts to control these factors and actions (e.g., wetland protection, pollution reduction or prevention, registration of pesticides, proper waste

disposal, public information)—that is, whether EPA’s efforts

maintain or improve ecological condition.

Source: Klemm D.J., et al. Development and Evaluation of a 

Macroinvertebrate Biotic Integrity Index (MBII) for Regionally Assessing 

Mid-Atlantic Highlands Streams. 2003.

26%

Poor

57%

Fair

Fish Index Macroinvertebrate Index

17%

Good

Source: McCormick F.H., et al. Development of an Index of Biotic Integrity for the MidAtlantic Highlands Region. 2001.

Note: No fish caught does not indicate poor condition. Some streams naturally do 

not have fish.

21%

No fish

caught

14%

Poor

38%

Fair

27%

Good

Exhibit 5-11: Fish and Macroinvertebrate Indices of Biotic Integrity
Chapter 5 - Ecological Condition

5-18

EPA’s Draft Report on the Environment 2003

Challenges in Developing Ecological Condition Indicators

Challenges in Developing Ecological Condition Indicators

Americans recognize the value of consistent and unbiased surveys of indicators focused on the state of the

economy as elements in maintaining a strong economy. Such surveys develop and track numbers on poverty, agricultural productivity, consumer prices, housing starts, and a

host of business parameters. Each of these indicators is

backed by a process for collecting and reporting the information and a sound rationale for its use as one indicator of economic condition. 

Although not everyone understands the exact calculations or

data sources, almost everyone seems to pay close attention

to the indicators’ ups and downs.

No comparable system exists to measure the ecological state

of the nation. As a result, adequate data for nationwide

trends exist for only a few indicators of ecological condition

(shown by the solid circles in Exhibit 5-12). Other indicators

(open circles) do have some data, but the data have only

been collected once or for limited geographic regions. The

clear message is that most of the data needed to track ecological condition have only begun to be collected, and only

for limited parts of the nation thus far. This situation will

improve over the next few years, but most of the gaps in

Exhibit 5-12 are likely to remain for some time to come,

because of several major challenges to developing adequate

indicators of national ecological condition:

■ Indicators must be tied to conceptual models that capture

how ecosystems respond to single and multiple stressors at

various scales.

■ Federal, state, and local monitoring organizations must find

a way to coordinate and integrate their activities to meet

multiple, potentially conflicting, data needs.

■ Mechanisms must be found to ensure long-term commitments to measuring selected indicators over long periods

and in standardized ways, to establish comparable baselines

and trends. 

■ Indicators must simplify complex data in ways that make

them meaningful and useful to decision-makers and the

public.

None of these challenges appears insurmountable, but the

gaps in Exhibit 5-12 indicate that much remains to be done. 
5-19

Chapter 5 - Ecological Condition

EPA’s Draft Report on the Environment 2003

Challenges in Developing Ecological Condition Indicators

Essential Ecological Attribute

Landscape Condition

Biotic Condition

Ecological Processes

Chemical and Physical Characteristics

Hydrology and Geomorphology

Natural Disturbance Regimes

Forests Farmlands Grasslands/ 

Shrublands Fresh Waters Coasts and 

Oceans

The 

Nation

Exhibit 5-12: Distribution of available ecological indicators across the ecosystem types

Extent of Ecological System/Habitat Types

Landscape Composition

Landscape Pattern/Structure

Species and Populations

Organism Condition

Energy Flow

Material Flow

Nutrient Concentrations

Other Chemical Parameters

Trace Organic/Inorganic Chemicals

Physical Parameters

Ecosystems and Communities

Surface and Ground Water Flows

Dynamic Structural Conditions

Sediment and Material Transport

Frequency

Urban/ 

Suburban

Adequate national data for assessing condition Limited national data for assessing condition

Note: Each circle, whether open or solid, represents an indicator presented in the Technical Document.
Chapter 5 - Ecological Condition

5-20

EPA’s Draft Report on the Environment 2003

Endnotes 

1 Chapter 5 – Ecological Condition, of the Report on the

Environment Technical Document accompanying this report is

organized differently, posing questions about the condition of

various ecosystem types and presenting a broader set of indicators that report on essential ecological attributes for each

ecosystem type.

2 U.S. Environmental Protection Agency. Framework for

Assessing and Reporting on Ecological Condition, EPA SABEPEC-02-009. Washington, DC: U.S. Environmental

Protection Agency, Science Advisory Board, June 2002.

3 The H. John Heinz III Center for Science, Economics and the

Environment. The State of the Nation’s Ecosystems: Measuring

the Lands, Waters, and Living Resources of the United States,

New York, NY: Cambridge University Press, September 2002.

4 U.S. Department of Agriculture Forest Service. Draft

Resource Planning and Assessment Tables. August 12, 2002.

(September 2003; http://www.ncrs.fs.fed.us/4801/FIADB/

rpa_tabler/ Draft_RPA_2002_Forest_Resource_Tables.pdf).

5 The Heinz Center. State of the Nation’s Ecosystems: Measuring

the Lands, Waters, and Living Resources of the United States,

2002. op. cit.

6 Dahl, T.E. Status and Trends of Wetlands in the Conterminous

United States 1986 to 1997, Washington, DC: U.S. Fish and

Wildlife Service, 2000.

7 U.S. Department of Agriculture. Summary Report: 1997

National Resources Inventory (Revised December 2000),

Washington, DC: Natural Resources Conservation Service and

Ames, Iowa: Iowa State University, Statistical Laboratory,

2000.

8 Ibid.

9 The Heinz Center. State of the Nation’s Ecosystems: Measuring

the Lands, Waters, and Living Resources of the United States,

2002. op. cit.

10 Ibid.

11 Ibid.

12 Moore, K.A., D.J. Wilcox, and R.J. Orth. Analysis of the

abundance of submersed aquatic vegetation communities in

the Chesapeake Bay. Estuaries 23 (1): 115-127 (2000).

13 Stein, B.A., L.S. Kutner, and J.S. Adams. Precious Heritage:

The Status of Biodiversity in the United States, New York, NY:

Oxford University Press, 2000.

14 U.S. Environmental Protection Agency, America’s Wetlands:

Our Vital Link Between Land and Water, EPA 843-K-95-001.

Washington, DC: U.S. Environmental Protection Agency,

Office of Wetlands, Oceans and Watersheds, December 1995.

15 U.S. Department of Agriculture. National Report on

Sustainable Forests - 2003. Final Draft, Washington, DC: U.S.

Department of Agriculture, Forest Service, November 2002.

16 The Heinz Center. State of the Nation’s Ecosystems:

Measuring the Lands, Waters, and Living Resources of the United

States, 2002. op. cit.

17 Stein, et al. Precious Heritage: The Status of Biodiversity in the

United States, 2000. op. cit.

18 Ibid.

19 The Heinz Center. State of the Nation’s Ecosystems:

Measuring the Lands, Waters, and Living Resources of the United

States, 2002. op. cit.

20 U.S. Environmental Protection Agency. America’s Wetlands:

Our Vital Link Between Land and Water, 1995. op.cit

Endnotes
5-21

Chapter 5 - Ecological Condition

EPA’s Draft Report on the Environment 2003

21 The Heinz Center. State of the Nation’s Ecosystems:

Measuring the Lands, Waters, and Living Resources of the United

States, 2002. op. cit.

22 Ibid.

23 Ibid. Based on data from the U.S. Geological Survey,

Biological Resources Division.

24 U.S. Department of Agriculture. National Report on

Sustainable Forests - 2003. Final Draft. 2002. op. cit.

25 The Heinz Center, State of the Nation’s Ecosystems:

Measuring the Lands, Waters, and Living Resources of the United

States, 2002. op.cit.

26 Ibid. Based on data from the U.S. Geological Survey,

Biological Resources Division.

27 U.S. Environmental Protection Agency. National Coastal

Condition Report, EPA 620-R-01-005. Washington, DC: U.S.

Environmental Protection Agency, Office of Research and

Development and Office of Water, September 2001.

28 National Research Council. Ecological Indicators for the

Nation, Washington, DC: National Academies Press, 2000.

29 U.S. Environmental Protection Agency. Framework for

Assessing and Reporting on Ecological Condition, 2002. op. cit.

30 The Heinz Center. State of the Nation’s Ecosystems:

Measuring the Lands, Waters, and Living Resources of the United

States, 2002. op. cit.

31 Ibid

32 Vitousek, P., S. Hattenschwiller, L. Olander, and S. Allison.

Nitrogen and nature. Ambio 31: 97-101 (2002).

Endnotes

33 Rabalais, N.N., R. E. Turner, D. Justic, Q. Dortch, and W.J.

Wiseman, Jr. Characterization of Hypoxia: Topic I Report for the

Integrated Assessment on Hypoxia in the Gulf of Mexico, NOAA

Coastal Ocean Program Decision Analysis Series No. 15.

Silver Spring, MD: National Oceanic and Atmospheric

Administration, 1999.

34 U.S. Geological Survey. The Quality of our Nation’s Waters:

Nutrients and Pesticides, U.S. Geological Survey Circular 1225.

Reston, VA: National Water Quality Assessment Program,

1999.

35 The Heinz Center. State of the Nation’s Ecosystems:

Measuring the Lands, Waters, and Living Resources of the United

States, 2002. op. cit.

36 Ibid.

37 Ibid.

38 Ibid.

39 Ibid.

40 U.S. Department of Agriculture. Summary Report 1997

National Resources Inventory (Revised December 2000), 2000.

op. cit.

41 The Heinz Center. State of the Nation’s Ecosystems:

Measuring the Lands, Waters, and Living Resources of the United

States, 2002. op. cit.

42 Ibid.

43 U.S. Department of Agriculture. National Report on

Sustainable Forests - 2003. Final Draft, 2002. op. cit.
Chapter 5 - Ecological Condition

5-22

EPA’s Draft Report on the Environment 2003

44 The Heinz Center. State of the Nation’s Ecosystems:

Measuring the Lands, Waters, and Living Resources of the United

States, 2002. op. cit.

45 Ibid.

46 National Interagency Fire Center. Wildland Fire Statistics.

Boise, ID. 2003. (March 22, 2003;

http://www.nifc.gov/stats/wildlandfirestats.html). 

47 Lynch, J.A., V.C. Bowersox, and J.W. Grimm. Changes in sulfate deposition in eastern USA following implementation of

phase I of Title IV of the Clean Air Act Amendments of 1990.

Atmospheric Environment 34 (11): 1665-1680 (2000).

48 Driscoll, C.T., G.B. Lawrence, A. Bulger, T. Butler, C. Cronan,

E.C. Eagar, K.F. Lambert, G.E. Likens, J. Stoddard, and K.C.

Weathers. Acidic deposition in the northeastern United

States: Sources, inputs, ecosystem effects and management

strategies. Bioscience 51: 180-198 (2001).

49 U.S. Environmental Protection Agency. Acid Rain: Response

of Surface Water Chemistry to the Clean Air Act Amendments of

1990, EPA 620-R-02-004. Research Triangle Park, NC: U.S.

Environmental Protection Agency, Office of Research and

Development, January 2003.

Endnotes

50 Karr, J.R., L.S. Fore, and E.W. Chu. Making Biological

Monitoring More Effective: Integrating Biological Sampling with

Analysis and Interpretation, Washington, DC: U.S. Environmental Protection Agency, Office of Policy Planning and

Evaluation, 1997. 

51 Karr, J.R. and E.W. Chu. Restoring Life in Running Waters:

Better Biological Monitoring, Washington, DC: Island Press,

1999.

52 McCormick, F.H., R.M. Hughes, P.R. Kaufmann, D.V. Peck, J.L.

Stoddard, and A.T. Herlihy. Development of an index of biotic

integrity for the mid-Atlantic Highlands region. Transactions of

the American Fisheries Society 130: 857-877 (2001).

53 Ibid.

54 Klemm, D.J., K.A. Blocksom, F.A. Fulk, A.T. Herlihy, R.M.

Hughes, P.R. Kaufmann, D.V. Peck, J.L. Stoddard, W.T. Thoeny,

M.B. Griffith, and W.S. Davis. Development and evaluation of

a Macroinvertebrate Biotic Integrity Index (MBII) for regionally assessing Mid-Atlantic Highlands streams. Environmental

Management 31(5): 656-669 (2003).
6-1

Chapter 6 - 

Working Together for

Environmental Results
Chapter 6 - Working Together for Environmental Results

6-2

EPA’s Draft Report on the Environment 2003

As this report shows, the United States has made great

strides in meeting environmental challenges over the

past three decades. Our air is cleaner, our drinking

water safer, our waste management practices more sound. The

health of the American people is generally improving. Yet

environmental and health challenges remain and there is much

we don’t know about the condition of the environment and

human health. To better understand the status of and trends

in the environment, and to better manage environmental protection programs, we need better indicators of environmental

and human health.

Using an integrated system of local, regional, and national

indicators and monitoring would strengthen our approach to

protecting the environment. With such a system in place, we

could better:

■ Assess and document the current state of the environment

at the national level and measure our progress toward

reaching our environmental goals.

■ Understand the relationships between stressors on the

environment and their ultimate effects on ecological condition and human health.

■ Focus our environmental protection resources on areas of

greatest concern.

■ Communicate with the American people about what is happening, why, and how best to safeguard human health and

the environment.

With this picture in mind, this final chapter explores the key

challenges in developing better indicators, and the next steps

that EPA proposes to take with its partners to address these

challenges. 

Key Challenges 

Developing a useful set of environmental indicators is a

daunting task. EPA has identified some of the major issues

that require careful consideration as a system of indicators is

developed and implemented.

Addressing Data Needs to Support Better Indicators.

Because of a lack of national indicators, we cannot provide

complete answers to many of the questions posed in this

report. (Similarly, 44 percent of the indicators in the Heinz

Center’s The State of the Nation’s Ecosystems could not be

reported nationally.1) In addition, many “national” data sets

do not cover the entire country, but only a subset, such as

the coastal U.S., major watersheds, or the Pacific Northwest.

Further, for many indicators, data are not available for more

than one time period, limiting our ability to discern a trend in

environmental condition or human health. This draft report

begins to identify where additional data are needed to support national indicators, but a thorough review is needed to

identify data needs and to set priorities.

Improving Data Collection and Analysis. Improving how we

collect and analyze data remains a significant challenge. Many

government agencies and other groups gather similar environmental data to satisfy various program objectives and

goals. Yet, differences—and, in some cases, inadequacies—

in approaches to data collection and analysis often limit the

broader use of these data. For example, states gather comprehensive data on water quality, but differences in monitoring

approaches limit our ability to provide a picture of the water

quality at the national level. Developing and applying standard data collection and analysis approaches are critical to

ensuring comparability of data, and to enabling greater use of

the extensive environmental and health data already being

collected.
6-3

Chapter 6 - Working Together for Environmental Results

EPA’s Draft Report on the Environment 2003

Reaching Agreement on an Integrated Set of Indicators.

National indicators provide a picture of the overall condition

of our nation’s environment and health, and inform national

environmental policy. But regional and local indicators are

also needed to guide regional and local policy while answering the questions Americans have about the conditions in

their backyard that affect them most: Is my drinking water

safe? Does the air in my community meet health standards?

National, regional, and local indicators all serve important

roles in informing the public and assisting governments and

others in protecting our environment and human health. A

major challenge before us is reaching agreement on an integrated core set of national, regional, and local indicators and

putting them into practice. 

Making Indicators More Understandable and Usable.

Indicators can be powerful tools, but only if they clearly communicate environmental conditions to decision-makers and

the public. For example, many Americans are familiar with the

color-coded alerts associated with the Air Quality Index and

adjust their activity accordingly when “code red” days occur.

Because of their technical nature, however, indicators often

can be difficult to understand. An important challenge, therefore, is developing more indices that clearly communicate

environmental conditions and trends. Further, for an indicator

or index to be useful for decision-makers, thresholds or criteria distinguishing acceptable from unacceptable conditions

are needed. Such thresholds or criteria currently do not exist

for many indicators, and need to be identified. 

Understanding Cause and Effect. Effective public policies

and programs to protect the health and environment require

knowing the causes of the problems they seek to correct. In

some cases, current science supports causal linkages between

a specific exposure and known effects on human health or

ecological condition—for example, the link between exposure

to environmental tobacco smoke and an increased risk of

developing lung cancer. But the link between specific environmental pollutants and the effect on human health and ecological condition is complex and often difficult to describe.

Understanding and quantifying causality—that is, sorting out

the role of the environment and the role of other factors and

their interactions—remains a significant scientific challenge. 

Partnerships for Better Environmental Indicators

Addressing the challenges described above is a task far

greater than EPA can undertake alone. Success requires a sustained and coordinated commitment from many partners:

other federal agencies; state, tribal, and local governments;

the research community; nongovernmental organizations; and

industry. It will also require collaborative analysis and replication of many of the indicator projects under way nationwide,

and around regional resources of great environmental importance. (For more information about such projects, see

http://www.epa.gov/indicators/). 

Such cooperative efforts are already in progress. As mentioned, many of the indicators included in this draft report

were developed by other federal, state, regional, local, and

tribal governments and the nonprofit sector. Additionally, in

December 2002, the White House Council on Environmental

Quality (CEQ) launched a new effort to enhance coordination

among federal agencies and to develop policy guidance on

the future development of environmental and sustainable

development indicators. The CEQ working group will: 

■ Develop agreement around a set of national-level environmental indicators that can be linked to regional and local

conditions.

■ Explore opportunities for collaboration among and between

federal agencies, state, regional, and local agencies, nongovernmental organizations, and private-sector groups to

improve the validity, reliability, consistency, and coverage of

the data used for indicators.

■ Consider how statistical reporting and data collection

should be organized within the federal government, recognizing the data needs of agencies’ programs and statutory

authorities. 

The goal of this effort is to have interlocking sets of environmental and human health indicators that can inform decisions

at the local, state, regional, and national levels. 
Chapter 6 - Working Together for Environmental Results

6-4

EPA’s Draft Report on the Environment 2003

Next Steps

EPA is committed to being an active partner in this national

effort. Within EPA, the next step is to develop—in concert

with the CEQ indicators working group—a long-term strategy

for environmental indicators that builds on this draft report.

Key components of that strategy will be based on ideas generated by discussions with EPA’s partners and the general

public. Through such discussions, we intend to collaborate

with other government agencies to reach agreement on an

integrated set of national, regional, and local indicators and

how best to put them into practice in planning and managing

programs and in communicating environmental and health

outcomes to the nation. 

Endnote

1 The H. John Heinz III Center for Science, Economics and the

Environment. The State of the Nation’s Ecosystems: Measuring

Lands, Waters, and Living Resources of the United States, New

York, NY: Cambridge University Press, September 2002.

Your participation and feedback, therefore, is a vital component of the success of the Environmental Indicators Initiative.

Please visit our web site at http://www.epa.gov/indicators/,

to learn more about the Environmental Indicators Initiative

activities and to provide your input. Together, we are working

toward a results-based management system that will ensure

cleaner air, purer water, and better protected land for generations of Americans to come.
A-1

Appendix A - Summary of

Questions and Indicators
Appendix A - Summary of Questions and Indicators

EPA’s Draft Report on the Environment 2003

A-2 Cleaner Air

Outdoor Air Quality

Question Indicator Name Technical Document Reference

What is the quality of outdoor air in the United States? Number and percentage of days that Metropolitan Statistical Areas have Air

Quality Index (AQI) values greater than 100

1.1.1

Number of people living in areas with air quality levels above the National Ambient

Air Quality Standards (NAAQS) for ozone (8-hour) and Particulate Matter (PM2.5)

1.1.1.a

Ambient concentrations of ozone, 8-hour 1.1.1.b

Ambient concentrations of particulate matter (PM2.5) 1.1.1.b

Visibility 1.1.1.c

Deposition: wet sulfate and wet nitrogen 1.2.1

Ambient concentrations of selected air toxics 1.1.1.d

What contributes to outdoor air pollution? Emissions of particulate matter, sulfur dioxide, nitrogen oxides, and volatile organic

compounds

1.1.2.a

Lead emissions 1.1.2.a

Air toxics emissions 1.1.2.b

Emissions (utility): sulfur dioxide and nitrogen oxides 1.2.2

What human health effects are associated with outdoor air

pollution?

No indicator identified. Also see Human Health Chapter. 1.1.3

What ecological effects are associated with outdoor air 

pollution?

No indicator identified. Also see Ecological Condition Chapter. 1.1.4 & 1.2.3

Indoor Air Quality

What is the quality of the air in buildings in the United

States?

U.S. homes above EPA’s radon action levels 1.3.1

Percentage of homes where young children are exposed to environmental tobacco

smoke

1.3.1

What contributes to indoor air pollution? No indicator identified 1.3.2

What human health effects are associated with indoor air 

pollution?

No indicator identified 1.3.3

Global Issues

What is happening to the Earth’s ozone layer? Ozone levels over North America 1.4.1

What is causing changes to the ozone layer? Worldwide and U.S. production of ozone-depleting substances 1.4.2

What human health and ecological effects are associated

with stratospheric ozone depletion?

No indicator identified 1.4.3 & 1.4.4

Cleaner Air - Summary of Questions and Indicators
Appendix A - Summary of Questions and Indicators

EPA’s Draft Report on the Environment 2003

Purer Water A-3

Waters and Watersheds

Question Indicator Name Technical Document

Reference

What is the condition of waters and watersheds in the 

United States?

No indicator identified 2.2.1

What is the condition of coastal waters? Water clarity in coastal waters 2.2.3

Dissolved oxygen in coastal waters 2.2.3

What are the extent and condition of wetlands? Wetland extent and change 2.2.2

Sources of wetland change/loss 2.2.2

What are stressors on waters and watersheds? Altered fresh water ecosystems 2.2.1

Percent urban land cover in riparian areas 2.2.4.a

Agricultural land in riparian areas 2.2.4.a

Changing stream flows 2.2.4.a

Atmospheric deposition of nitrogen 2.2.4.b

Nitrate in farmland, forested, and urban streams and ground water 2.2.4.b

Total nitrogen in coastal waters 2.2.4.b

Phosphorus in farmland, forested, and urban streams 2.2.4.b

Total phosphorus in coastal waters 2.2.4.b

Phosphorus in large rivers 2.2.4.b

Atmospheric deposition of mercury 2.2.4.c

Chemical contaminants in streams 2.2.4.c

Sediment contamination of inland waters 2.2.4.c

Sediment contamination of coastal waters 2.2.4.c

Pesticides in farmland streams, and ground water 2.2.4.c

Toxic releases to water of mercury, dioxin, lead, PCBs, and PBTs 2.2.4.c

What ecological effects are associated with impaired waters? Benthic Community Index (coastal waters). Also see Ecological Condition Chapter. 2.2.5

Drinking Water

What is the quality of drinking water? Population served by community water systems that meet all health-based standards 2.3.1

What are sources of drinking water contamination? No indicator identified 2.3.2

What human health effects are associated with drinking contaminated water?No indicator identified. Also see Human Health Chapter. 2.3.3

Recreation in and on the Water

What is the condition of waters supporting recreational use? Number of beach days that beaches are closed or under advisory 2.4.1

What are sources of recreational water pollution? No indicator identified. Also see Ecological Condition Chapter. 2.4.2

What human health effects are associated with recreation in 

contaminated waters?

No indicator identified. Also see Human Health Chapter. 2.4.3

Consumption of Fish and Shellfish

What is the condition of waters that support consumption of

fish and shellfish?

Percent of river miles and lake acres under fish consumption advisories 2.5.1

Contaminants in fresh water fish 2.5.1

Number of watersheds exceeding health-based national water quality criteria for mercury

and PCBs in fish tissue

2.5.1

What are contaminants in fish and shellfish, and where do they

originate?

No indicator identified 2.5.2

What human health effects are associated with consuming contaminated fish and shellfish?No indicator identified 2.5.3

Purer Water - Summary of Questions and Indicators
Appendix A - Summary of Questions and Indicators

EPA’s Draft Report on the Environment 2003

A-4 Better Protected Land

Better Protected Land - Summary of Questions and Indicators

Land Use

Question Indicator Name Technical Document Reference

What is the extent of developed lands? Extent of developed lands 3.1.1

Extent of urban and suburban lands 3.1.1

What is the extent of farmlands? Extent of agricultural land uses 3.1.2

What is the extent of grasslands and shrublands? Extent of grasslands and shrublands 3.1.3

What is the extent of forest lands? Extent of forest area, ownership, and management 3.1.4

What human health effects are associated with land use? No indicator identified 3.1.5

What ecological effects are associated with land use? No indicator identified. Also see Ecological Condition Chapter. 3.1.6

Chemicals in the Landscape

How much and what types of toxic substances are released

into the environment?

Quantity and type of toxic chemicals released and managed 3.2.1

What are the volume, distribution, and extent of pesticide

and fertilizer use?

Agricultural pesticide use 3.2.2

Fertilizer use 3.2.3

What is the potential disposition of chemicals from land? Pesticide residues in foods 3.2.4

Potential pesticide runoff from farm fields 3.2.4

Risk of nitrogen export 3.2.4

Risk of phosphorus export 3.2.4

What human health effects are associated with pesticides, 

fertilizers, and toxic substances?

No indicator identified 3.2.5

What ecological effects are associated with pesticides, 

fertilizers, and toxic substances?

No indicator identified 3.2.6

Waste and Contaminated Lands

How much and what types of waste are generated and 

managed?

Quantity of municipal solid waste (MSW) generated and managed 3.3.1

Quantity of RCRA hazardous waste generated and managed 3.3.1

Quantity of radioactive waste generated and in inventory 3.3.1

What is the extent of land used for waste management? Number and location of municipal solid waste (MSW) landfills 3.3.2

Number of RCRA hazardous waste management facilities 3.3.2

What is the extent of contaminated lands? Number and location of Superfund National Priority List (NPL) sites 3.3.3

Number and location of RCRA Corrective Action sites 3.3.3

What human health effects are associated with waste 

management and contaminated lands?

No indicator identified 3.3.4

What ecological effects are associated with waste management and contaminated lands?No indicator identified 3.3.5
Appendix A - Summary of Questions and Indicators

EPA’s Draft Report on the Environment 2003

Human Health A-5

Human Health - Summary of Questions and Indicators

Health Status of the United States

Question Indicator Name Technical Document Reference

What are the trends and indicators for health and disease in

the United States?

Life expectancy 4.3.1

Cancer incidence 4.3.2

Cancer mortality 4.3.2

Cardiovascular disease mortality 4.3.2

Cardiovascular disease prevalence 4.3.2

Chronic obstructive pulmonary disease mortality 4.3.2

Asthma mortality 4.3.2

Asthma prevalence 4.3.2

Cholera prevalence 4.3.3

Cryptosporidiosis prevalence 4.3.3

E. coli O157:H7 prevalence 4.3.3

Hepatitis A prevalence 4.3.3

Salmonellosis prevalence 4.3.3

Typhoid Fever prevalence 4.3.3

Shigellosis prevalence 4.3.3

What are the trends for children’s environmental health

issues?

Infant mortality 4.3.4

Low birthweight incidence 4.3.4

Childhood cancer mortality 4.3.4

Childhood cancer incidence 4.3.4

Childhood asthma mortality 4.3.4

Childhood asthma prevalence 4.3.4

Deaths due to birth defects 4.3.4

Birth defect incidence 4.3.4

Environmental Pollution and Disease

What is the role of the environment in disease? Blood lead level 4.4.3

Cardiovascular disease mortality 4.3.2

Chronic obstructive pulmonary disease mortality 4.3.2

Cholera prevalence 4.3.3

Typhoid fever prevalence 4.3.3

Measuring Exposure to Environmental Pollution

How can exposure data advance understanding of the role of

the environment in disease?

Blood lead level 4.4.3

Blood mercury level 4.4.3

Blood cotinine level 4.4.4

Urine organophosphate level to indicate pesticides 4.4.6
Appendix A - Summary of Questions and Indicators

EPA’s Draft Report on the Environment 2003

A-6 Ecological Condition

Ecological Condition - Summary of Questions and Indicators

National Ecological Condition

Question Indicator Name Technical Document Reference

What is the ecological condition of the United States? 5.8

Landscape Condition Extent of ecosystem/land cover types (forests, farmlands, urban/suburban, 

grasslands/shrublands, fresh waters, coasts and oceans)

3.1.1, 3.1.2, 3.1.3, 3.1.4, 

5.6, 5.7

Biotic Condition At-risk native species 5.8

Benthic Community Index 5.7

Populations trends of invasive and native non-invasive bird species 5.4

Tree condition 5.2

Chemical and Physical Characteristics Nitrate levels in streams by ecosystems 2.2.4.b

Ecological Processes Terrestrial Plant Growth Index 5.8

Movement of nitrogen 5.8

Hydrology and Geomorphology Changing stream flows 2.2.4.a

Soil erosion 5.2, 5.3

Natural Disturbance Regimes Forest disturbances: fire, insects, and disease 5.2
B-1

Appendix B - Types of Waste

and Contaminated Lands
Appendix B - Types of Waste and Contaminated Lands

B-2

EPA’s Draft Report on the Environment 2003

Types of Waste

Type Description

Municipal Solid Waste (MSW) is the waste discarded by households, hotels/motels, and commercial, institutional, and industrial sources. MSW typically consists of everyday items such as

product packaging, grass clippings, furniture, clothing, bottles, food scraps, newspapers, appliances, paint, and batteries. It does not include waste water. In 2000, 232 million tons of MSW

were generated.1

The term “RCRA hazardous waste” applies to certain types of hazardous wastes that appear on

EPA’s regulatory listing (RCRA) or that exhibit specific characteristics of ignitability, corrosiveness, reactivity, or excessive toxicity. More than 40 million tons of RCRA hazardous waste were

generated in 1999.2

Radioactive waste is the garbage, refuse, sludge, and other discarded material, including solid,

liquid, semi-solid, or contained gaseous material that must be managed for its radioactive content.3 The technical names for the types of waste that are considered “radioactive waste” for

this report are high-level waste, spent nuclear fuel, transuranic waste, low-level waste, mixed lowlevel waste, and contaminated media (see Appendix D for definitions of these terms).

Extraction activities such as mining and mineral processing are large contributors to the total

amount of waste generated and land contaminated in the U.S. EPA estimates that 5 billion tons

of mining wastes were generated in 1988.4

Industrial non-hazardous waste is process waste associated with electric power generation and

manufacturing of materials such as pulp and paper, iron and steel, glass, and concrete. This

waste usually is not classified as either municipal waste or RCRA hazardous waste by federal or

state laws. State, tribal, and some local governments have regulatory programs to manage

industrial waste. EPA estimated that 7.6 billion tons of industrial non-hazardous wastes were

generated in 1988.5

Most household products that contain corrosive, toxic, ignitable, or reactive ingredients are

considered household hazardous waste. Examples include most paints, stains, varnishes, solvents, and household pesticides. Special disposal of these materials is necessary to protect

human health and the environment, but some amount of this type of waste is improperly disposed of by pouring the waste down the drain, on the ground, in storm sewers, or by discarding

the waste with other household waste as part of municipal solid waste. EPA estimates that

Americans generate 1.6 million tons of household hazardous waste per year, with the average

home accumulating up to 100 pounds annually.6

Municipal Solid Waste 

RCRA Hazardous Waste 

Radioactive Waste 

Extraction Wastes

Industrial Non-Hazardous

Waste

Household Hazardous Waste
B-3

Appendix B - Types of Waste and Contaminated Lands

EPA’s Draft Report on the Environment 2003

Agricultural Waste

Construction and

Demolition Waste

Medical Waste

Oil and Gas Waste

Sludge

Agricultural solid waste is waste generated by the rearing of animals and the production and

harvest of crops or trees. Animal waste, a large component of agricultural waste, includes waste

from livestock, dairy, milk, and other animal-related agricultural and farming practices. Some of

this waste is generated at sites called Confined Animal Feeding Operations (CAFOs), The waste

associated with CAFOs results from congregating animals, feed, manure, dead animals, and production operations on a small land area. Animal waste and wastewater can enter water bodies

from spills or breaks of waste storage structures (due to accidents or excessive rain), and nonagricultural application of manure to crop land.7, 8 National estimates are not available. 

Construction and demolition debris is waste generated during construction, renovation, and

demolition projects. This type of waste generally consists of materials such as wood, concrete,

steel, brick, and gypsum. (The MSW data in this report do not include construction and demolition debris, even though sometimes construction and demolition debris are considered MSW.)

National estimates are not available. 

Medical waste is any solid waste generated during the diagnosis, treatment, or immunization of

human beings or animals, in research, production, or testing. National estimates are not available. 

Oil and gas production wastes are the drilling fluids, produced waters, and other wastes associated with the exploration, development, and production of crude oil or natural gas that are conditionally exempted from regulation as hazardous wastes. National estimates are not available. 

Sludge is the solid, semisolid, or liquid waste generated from municipal, commercial, or industrial

wastewater. National estimates are not available. 

Types of Waste

Type Description
Appendix B - Types of Waste and Contaminated Lands

B-4

EPA’s Draft Report on the Environment 2003

Congress established the Superfund Program in 1980 to clean up abandoned hazardous waste

sites throughout the U.S. The most seriously contaminated sites are on the National Priorities

List (NPL). As of October 2002, there were 1,498 sites on the NPL.

9

EPA and authorized states have identified 1,714 hazardous waste management facilities that are

the most seriously contaminated and may pose significant threats to humans or the environment.10 Some RCRA Corrective Action sites are also identified by the Superfund Program as

NPL sites. 

Many petroleum and hazardous substances are stored in underground storage tanks (USTs).

EPA regulates many categories of UST systems, including those at gas stations, convenience

stores and bus depots. USTs that have failed due to faulty materials, installation, operating procedures, or maintenance systems are categorized as leaking underground storage tanks (LUSTs).

LUSTs can contaminate soil, ground water, and sometimes drinking water. Vapors from UST

releases can lead to explosions and other hazardous situations if those vapors migrate to a confined area such as a basement. LUSTs are the most common source of groundwater contamination, and petroleum is the most common groundwater contaminant.11, 12 According to EPA’s

corrective action reports, in 1996, there were 1,064,478 active tanks located at approximately

400,000 facilities. In 2002, there were 697,966 active tanks (a 34 percent decrease) and

1,525,402 closed tanks (a 42 percent increase). The number of national USTs within each area

of the U.S. has not fluctuated significantly between 1996–2001. As of the fall of 2002,

427,307 UST releases (LUSTs) were confirmed.13

Each year, thousands of oil and chemical spills occur on land and in water. Oil and gas materials

that have spilled include drilling fluids, produced waters, and other wastes associated with the

exploration, development, and production of crude oil or natural gas. Accurate national spill

data are not available. 

Approximately 0.54 million acres of land spanning 129 sites in over 30 states are contaminated

with radioactive and other hazardous materials as a result of activities associated with nuclear

weapons production and research. Although DOE is the landlord at most of these sites, other

parties, including other federal agencies, private parties, and one public university, also have

legal responsibilities over these lands.14

Brownfields are real property, the expansion, redevelopment or reuse of which may be complicated by the presence or potential presence of a hazardous substance, pollutant, or contaminate.15 Brownfields are often found in and around economically depressed neighborhoods. As

brownfields are cleaned and redeveloped, surrounding communities benefit from a reduction of

health and environmental risks, more functional space, and improved economic conditions. A

complete inventory of brownfields does not exist. According to the General Accounting Office

(1987), there are approximately 450,000 brownfields nationwide.16 The EPA’s national

Brownfield tracking system includes a large volume of data on brownfields across the nation, but

does not track all of them. EPA’s Brownfield Assessment Pilot Program includes data collected

from over 400 pilot communities.17

Types of Contaminated Lands

Type Description

Superfund National

Priorities List Sites

RCRA Corrective Action

Sites

Leaking Underground

Storage Tanks

Accidental Spill Sites

Land contaminated with

radioactive and other

hazardous materials

Brownfields
B-5

Appendix B - Types of Waste and Contaminated Lands

EPA’s Draft Report on the Environment 2003

Some Military Bases

Waste management sites

that were poorly designed

or poorly managed

Illegal dumping sites

Abandoned mine lands

Some (exact number or percentage unknown) military bases are contaminated as a result of a

variety of activities. A national assessment of land contaminated at military bases has not been

conducted. However, under the Base Realignment and Closure (BRAC) laws, closed military

bases undergo site investigation processes to determine extent of possible contamination and

the need for site cleanup. Currently, 204 military installations that have been closed or

realigned are undergoing environmental cleanup. These installations collectively occupy over

400,000 acres, though not all of this land is contaminated. Thirty-six of these installations are

on the Superfund NPL list, and, of these, 32 are being cleaned up under the Fast Track program

to make them available for other uses as quickly as possible.18

Prior to the 1970s, untreated waste was typically placed in open pits or directly onto the land.

Some of these early waste management sites are still contaminated. In other cases, improper

management of facilities (that were typically used for other purposes such as manufacturing)

resulted in site contamination. Federal and state cleanup efforts are now addressing those early

land disposal units and poorly-managed sites that are still contaminated. 

Also known as “open dumping” or “midnight dumping,” illegal dumping of such materials as construction waste, abandoned automobiles, appliances, household waste, and medical waste raises

concerns for safety, property values, and quality of life. People tend to dump illegally because

legal dumping costs money and/or is inconvenient. While a majority of illegally dumped waste is

not hazardous, some of it is, creating contaminated lands. 

Abandoned mine lands are sites that have historically been mined and have not been properly

cleaned up. These abandoned or inactive mine sites may include disturbances or features ranging from exploration holes and trenches to full blown, large-scale mine openings, pits, waste

dumps, and processing facilities. The Department of the Interior’s (DOI) Bureau of Land

Management (BLM) is presently aware of approximately 10,200 abandoned hardrock mines

located within the roughly 264 million acres under its jurisdiction. Various government and private organizations have made estimates over the years about the total number of abandoned

and inactive mines in the U.S., including estimates for the percent land management agencies,

and State and privately-owned lands. Those estimates range from about 80,000 to hundreds of

thousands of small to medium-sized sites. The BLM is attempting to identify, prioritize, and take

appropriate actions on those historic mine sites that pose safety risks to the public or present

serious threats to the environment.19

Types of Contaminated Lands

Type Description
Appendix B - Types of Waste and Contaminated Lands

B-6

EPA’s Draft Report on the Environment 2003

Appendix B - Endnotes

1 U.S. Environmental Protection Agency. Municipal Solid Waste in the

United States: 2000 Facts and Figures, EPA 530-S-02-001.

Washington, DC: U.S. Environmental Protection Agency, Office of

Solid Waste and Emergency Response, June 2002.

2 U.S. Environmental Protection Agency. The National Biennial RCRA

Hazardous Waste Report, EPA 530-R-01-009. Washington, DC: U.S.

Environmental Protection Agency, Office of Solid Waste and

Emergency Response, June 2001. 

3 U.S. Department of Energy (DOE). Radioactive Waste

Management. Order 435.1. July, 1999.

4 U.S. Environmental Protection Agency. EPA Report to Congress, Solid

Waste Disposal in the United States, Volumes I-II, EPA 530-SW-88-

011(B). Washington, DC: U.S. Environmental Protection Agency,

Office of Solid Waste and Emergency Response, October 1988.

5 Ibid

6 U.S. Environmental Protection Agency, Office of Solid Waste and

Emergency Response. Household hazardous waste. October 29,

2002. (February 25, 2003; 

http://www.epa.gov/epaoswer/non-hw/muncpl/hhw.htm).

7 U.S. Environmental Protection Agency. Fact Sheet: Notice of Data

Availability Concerning Proposed National Pollutant Discharge

Elimination System Permit Regulation and Effluent Limitations Guidelines

and Standards for Concentrated Animal Feeding Operations,

EPA 821-F-01-015. U.S. Environmental Protection Agency, Office of

Water, November 2001.

8 U.S. Environmental Protection Agency, Office of Water. Animal

feeding operations. 2002. (June 2002;

http://cfpub.epa.gov/npdes/home.cfm?program_id=7).

9 U.S. Environmental Protection Agency, Superfund Emergency

Response Program. National Priorities List Site Totals by Status and

Milestone. February 6, 2003. (October 2002; 

http://epa.gov/superfund/sites/query/queryhtm/npltotal.htm).

10 U.S. Environmental Protection Agency, Office of Solid Waste and

Emergency Response. Corrective action background. October 8,

2002. (October 15, 2002;

http://www.epa.gov/epaoswer/hazwaste/ca/backgnd.htm#5).

11 U.S. Environmental Protection Agency. National Water Quality

1998 Inventory Report to Congress: Ground Water and Drinking Water

Chapters, EPA 816-R-00-013. Washington, DC: U.S. Environmental

Protection Agency, Office of Water, August 2000.

12 U.S. Environmental Protection Agency. National Water Quality

1994 Inventory Report to Congress: Ground Water and Drinking Water

Chapters, EPA 813-R-96-001. Washington, DC: U.S. Environmental

Protection Agency, Office of Water, June 1996.

13 U.S. Environmental Protection Agency, Office of Solid Waste and

Emergency Response. End-of-year activity report memorandum to

UST regional division directors. December 23, 2002. (February 25,

2003; http://www.epa.gov/swerust1/cat/eoy02memo.pdf).

14 U.S. Department of Energy, Office of Environmental Management

and Office of Long-Term Stewardship. A Report to Congress on Longterm Stewardship Volume I - Summary Report, DOE EM-0563. January

2001.

15 U.S. Congress. Small Business Liability Relief and Brownfields

Revitalization Act, Public Law 107-118 (H.R. 2869). Washington, DC:

January, 2002.

16 General Accounting Office. Superfund: Extent of Nation's Potential

Hazardous Waste Problem Still Unknown, GAO/RCED-88-44.

Washington, DC: General Accounting Office, December 1, 1987.

17 U.S. Environmental Protection Agency, Office of Solid Waste and

Emergency Response. Brownfields assessment demonstration pilots.

October 17, 2002. (May 2002; 

http://www.epa.gov/brownfields/jlocat.htm).

18 U.S. Department of Defense. Fiscal Year 2001 Defense

Environmental Restoration Program Annual Report to Congress.

2001. (November 2002;

http://63.88.245.60/derparc_fy01/derp/indexTen.htm).

19 U.S. Department of the Interior, Bureau of Land Management.

Frequently asked questions on the Abandoned Mine Lands Cleanup

Program. August 9, 2002. (January, 2003;

http://www.blm.gov/aml/faqs.htm).
C-1

Appendix C - 

Acronyms and Abbreviations
Appendix C - Acronyms and Abbreviations

C-2

EPA’s Draft Report on the Environment 2003

AQI: Air Quality Index

BASE: Building Assessment Survey and Evaluation 

BEACH: Beaches Environmental Assessment and Coastal

Health Program

CDC: Centers for Disease Control and Prevention

CO: carbon monoxide

COPD: chronic obstructive pulmonary disease

CRP: Conservation Reserve Program

CWA: Clean Water Act

CWS: community water system

DDT: dichlorodiphenyl trichlorethane

EMAP: Environmental Monitoring and Assessment Program

EPA: Environmental Protection Agency

ETS: environmental tobacco smoke

GLFMP: Great Lakes Fish Monitoring Program

IBI: index of biotic integrity

IQ: intelligence quotient

LUST: leaking underground storage tank

MBSS: Maryland Biological Stream Survey

MSW: municipal solid waste

NAWQA: National Water Quality Assessment Program

NCFAP: National Center for Food and Agricultural Policy

NEI: National Emissions Inventory

NLCD: National Land Cover Dataset

NO2: nitrogen dioxide

NOX: nitrogen oxides

NOAA: National Oceanic and Atmospheric Administration

NPL: National Priorities List

NRCS: Natural Resources Conservation Service

NRI: National Resources Inventory 

PBTs: persistent bioaccumulative toxics

PCBs: polychlorinated biphenyls

PDP: Pesticides Data Program

POPs: persistent organic pollutants

PM2.5: particulate matter less than or equal to 2.5 micrometers in diameter

PM10: particulate matter less than or equal to 10 micrometers

in diameter

POPs: persistent organic pollutants

RCRA: Resource Conservation and Recovery Act 

SAB: EPA Science Advisory Board

SAV: submerged aquatic vegetation

SO2: sulfur dioxide

TESS: Toxic Exposure Surveillance System

TRI: Toxics Release Inventory

USDA: U.S. Department of Agriculture

USGS: U.S. Geological Survey 

UST: underground storage tank

UV: ultraviolet radiation

VOCs: volatile organic compounds

WBDO: waterborne disease outbreak

WMPC: waste minimization priority chemicals
D-1

Appendix D - 

Glossary of Terms
Appendix D - Glossary of Terms

EPA’s Draft Report on the Environment 2003

A complete glossary reference list can be found in EPA’s Report on

the Environment Technical Document, Appendix E.

A

acid deposition: A complex chemical and atmospheric phenomenon that occurs when emissions of sulfur and nitrogen

compounds are transformed by chemical processes in the

atmosphere and then deposited on earth in either wet or dry

form. The wet forms, often called “acid rain,” can fall to earth

as rain, snow, or fog. The dry forms are acidic gases or particulate matter.

advisory: A nonregulatory document that communicates risk

information to those who may have to make risk management

decisions. 

aerosol: 1. Small droplets or particles suspended in the

atmosphere, typically containing sulfur. They are emitted naturally (e.g., in volcanic eruptions) and as a result of human

activities such as burning fossil fuels. 2. The pressurized gas

used to propel substances out of a container. 

agricultural waste: Byproducts generated by the rearing of

animals and the production and harvest of crops or trees.

Animal waste, a large component of agricultural waste,

includes waste (e.g., feed waste, bedding and litter, and feedlot and paddock runoff) from livestock, dairy, and other animal-related agricultural and farming practices. 

air pollutant: Any substance in air that could, in high enough

concentration, harm man, other animals, vegetation, or material. Pollutants may include almost any natural or artificial

composition of matter capable of being airborne. It may be in

the form of solid particles, liquid droplets, gases, or a combination thereof. Generally, they fall into two main groups: (1)

those emitted directly from identifiable sources and (2) those

produced in the air by interaction between two or more primary pollutants, or by reaction with normal atmospheric conD-2

stituents, with or without photoactivation. Exclusive of pollen,

fog, and dust, which are of natural origin, about 100 contaminants have been identified. Air pollutants are often grouped

in categories for ease in classification; some of he categories

are: solids, sulfur compounds, volatile organic chemicals, particulate matter, nitrogen compounds, oxygen compounds,

halogen compounds, radioactive compound, and odors. 

air pollution: The presence of contaminants or pollutant

substances in the air that interfere with human health or welfare or produce other harmful environmental effects. 

air quality criteria: The levels of pollution and lengths of

exposure above which harmful health and welfare effects may

occur. 

air quality standards: The level of pollutants prescribed by

regulations that are not to be exceeded during a given time in

a defined area. 

air toxics: Air pollutants that cause or may cause cancer or

other serious health effects, such as reproductive effects or

birth defects, or adverse environmental and ecological effects.

Examples of toxic air pollutants include benzene, found in

gasoline; perchloroethylene, emitted from some dry cleaning

facilities; and methylene chloride, used as a solvent by a number of industries.

algal blooms: Sudden spurts of algal growth, which can

degrade water quality and indicate potentially hazardous

changes in local water chemistry. 

ambient air: Any unconfined portion of the atmosphere;

open air, surrounding air. 

ambient air quality standards: See criteria pollutants and

National Ambient Air Quality Standards.

anthropogenic: Originating from humans, not naturally

occurring. 
Appendix D - Glossary of Terms

EPA’s Draft Report on the Environment 2003

aquatic ecosystems: Salt water or fresh water ecosystems,

includes rivers, streams, lakes, wetlands, estuaries, and coral

reefs.

aquifer: An underground geological formation, or group of

formations, containing water; source of ground water for wells

and springs. 

arsenic: A silvery, nonmetallic element that occurs naturally in

rocks, soil, water, air, and plants and animals. It can be

released into the environment through natural activities such

as volcanic action, erosion of rocks, and forest fires or

through human actions. Approximately 90 percent of industrial arsenic in the U.S. is used as a wood preservative, but

arsenic is also used in paints, dyes, metals, drugs, soaps, and

semiconductors. Agricultural applications (used in rodent poisons and some herbicides), mining, and smelting also contribute to arsenic releases in the environment. It is a known

human carcinogen.

asbestos: Naturally occurring strong, flexible fibers that can

be separated into thin threads and woven. These fibers resist

heat and chemicals and do not conduct electricity. Asbestos

is used for insulation, making automobile brake and clutch

parts, and many other products. These fibers break easily and

form a dust composed of tiny particles that are light and

sticky. When inhaled or swallowed they can cause health

problems.

assemblage: The association of interacting populations of

organisms in a selected habitat.

B

beach day: A day that a beach would normally be open to

the public.

benthic: Occurring at or near the bottom of a body of water.

benthic organisms: The worms, clams, crustaceans, and

other organisms that live at the bottom of the estuaries and

the sea.

benthos: In fresh water and marine ecosystems, organisms

attached to, resting on, or burrowed into bottom sediments.

bioaccumulation: A process whereby chemicals (e.g., DDTs,

PCBs) are retained by plants and animals and increase in concentration over time. Uptake can occur through feeding or

direct absorption from water or sediments. 

biodiversity: The variety and variability among living organisms and the ecological complexes in which they occur.

Diversity can be defined as the number of different items and

their relative frequencies. The term encompasses three basic

levels of biodiversity: ecosystems, species, and genes.

biological diversity: See biodiversity.

biomass: All of the living material in a given area; often refers

to vegetation. 

biomonitoring: The assessment of human exposure to chemicals by measuring the chemicals or their metabolites (breakdown products) in human tissues or fluids such as blood or

urine. Blood and urine levels reflect the amount of the chemical in the environment that actually gets into the body.

biotic: Refers to living organisms.

biotic condition: The state of living things.

biotic integrity: The ability to support and maintain balanced, integrated functionality in the natural habitat of a

given region. 

body burden: The amount of various contaminants retained

in a person’s tissues.

D-3
Appendix D - Glossary of Terms

EPA’s Draft Report on the Environment 2003

brownfield: Real property, the expansion, redevelopment or

reuse of which may be complicated by the presence or potential presence of a hazardous substance, pollutant, or contaminant.

C

cadmium: A metal found in natural deposits as ores containing other elements. The greatest use of cadmium is primarily

for metal plating and coating operations, including transportation equipment, machinery and baking enamels, photography, and television phosphors. It is also used in

nickelcadmium and solar batteries and in pigments.

carcinogen: An agent that causes cancer.

chained dollars: A measure used to adjust for the effects of

inflation in the U.S. currency from year to year, such that a

consistent monetary value can be understood over time. A

chained dollar is based on the average weights of the cost of

goods and services in successive pairs of years. It is “chained”

because the second year in each pair, with its weights,

becomes the first year of the next pair.

chlorine: A greenish-yellow gas that is slightly soluble in

water. Chlorine is often used in disinfection of water and

treatment of sewage effluent as well as in the manufacture of

products such as antifreeze, rubber, and cleaning agents.

chromium: A heavy metal that occurs naturally in rocks,

plants, soil, and volcanic dust and gases. It is tasteless and

odorless. It can damage living things at low concentrations

and tends to accumulate in the food chain. 

cleanup: Action taken to deal with a release or threat of

release of a hazardous substance that could affect humans,

the environment, or both. The term “cleanup” is sometimes

used interchangeably with the terms “remedial action,”

“removal action,” “response action,” or “corrective action.”

coastal and ocean ecosystem: An ecosystem that consists

primarily of estuaries and ocean waters under a country’s

jurisdiction. U.S. waters extend to the boundaries of the U.S.

Exclusive Economic Zone, 200 miles from the U.S. coast. 

coastal wetland: Ecosystem found along the coasts and

closely linked to the nation’s estuaries, where sea water mixes

with fresh water to form an environment of varying salinities.

The plants in coastal wetlands have adapted to fluctuating

water levels and salinities to create tidal salt marshes, mangrove swamps, and tidal fresh water wetlands, which form

beyond the upper edges of tidal salt marshes where the influence of salt water ends. Fresh water coastal wetlands can also

be found adjacent to the Great Lakes.

community water system: A public water system that serves

at least 15 service connections used by year-round residents

or regularly serves at least 25 year-round residents. 

construction and demolition debris: Waste generated during building, renovation, and wrecking projects. This type of

waste generally consists of materials such as wood, concrete,

steel, brick, and gypsum.

contaminant: Any physical, chemical, biological, or radiological substance or matter that has an adverse effect on air,

water, or soil. 

contaminated land: Ground that has been polluted with

hazardous materials and requires cleanup or remediation.

Contaminated sites may contain both polluted objects (e.g.,

buildings, machinery) and land (e.g., soil, sediments, and

plants). 

contaminated media: Materials such as soil, sediment, water,

and sludge that are polluted at levels requiring cleanup or

further assessment.

contamination: Introduction into water, air, or soil of

microorganisms, chemicals, toxic substances, wastes, or waste

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water in a concentration that makes the medium unfit for its

next intended use. Also applies to surfaces of objects, buildings, and various household and agricultural use products. 

conterminous: Enclosed within one common boundary (e.g.,

the 48 conterminous states).

cotinine: A breakdown product (metabolite) of nicotine that

can be measured in urine.

criteria air pollutants: A group of six widespread and common air pollutants regulated by the EPA on the basis of standards set to protect public health or the environment. These

six criteria pollutants are carbon monoxide, lead, nitrogen

dioxide, ozone, particulate matter, and sulfur dioxide.

cropland: A National Resources Inventory land cover/use

category that includes areas used for the production of

adapted crops for harvest. Two subcategories of cropland are

recognized: cultivated and noncultivated. Cultivated cropland

comprises land in row crops or close-grown crops and also

other cultivated cropland, for example, hayland or pastureland that is in a rotation with row or close-grown crops.

Noncultivated cropland includes permanent hayland and horticultural cropland. 

D

designated uses: Those water uses identified in state water

quality standards that must be achieved and maintained as

required under the Clean Water Act. Uses can include fishing,

shellfish harvesting, public water supply, swimming, boating,

and irrigation. 

developed land: A combination of National Resource

Inventory land cover/use categories: large urban and built-up

areas, small built-up areas, and rural transportation land. 

dioxin: A group of chemically similar compounds, known

chemically as dibenzo-p-dioxins, that are created inadvertently during combustion, chlorine bleaching of pulp and paper,

and some types of chemical manufacturing. Tests on laboratory animals indicate that it is one of the more toxic anthropogenic (manmade) compounds. 

disinfection by-product: A compound formed by the reaction of a disinfectant such as chlorine with organic material in

the water supply; a chemical byproduct of the disinfection

process. 

dry deposition: The settling of gases and particles out of the

atmosphere. Dry deposition is a type of acid deposition,

more commonly referred to as “acid rain.” 

E

ecological indicators: Measurable characteristics related to

the structure, composition, or functioning of ecological systems; a measure, an index of measures, or a model that characterizes an ecosystem or one of its critical components; any

expression of the environment that quantitatively estimates

the condition of ecological resources, the magnitude of

stress, the exposure of biological components to stress, or

the amount of change in condition.

ecological processes: The metabolic functions of ecosystems—energy flow, elemental cycling, and the production,

consumption, and decomposition of organic matter.

ecosystem: 1. The interacting system of a biological community and its nonliving environmental surroundings. 2. A geographic area including all living organisms (people, plants,

animals, and microorganisms), their physical surroundings

(such as soil, water and air), and the natural cycles that sustain them. 

emissions standard: The maximum amount of air-polluting

discharge legally allowed from a single source, mobile or stationary. 

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endangered species: Animals, birds, fish, plants, or other living organisms threatened with extinction by anthropogenic

(human-caused) or natural changes in their environment.

Requirements for declaring a species “endangered” are contained in the Endangered Species Act. 

enrichment: The addition of nutrients (e.g., nitrogen, phosphorus, carbon compounds) from sewage effluent, agricultural

or urban runoff, or other sources to surface water. Enrichment

greatly increases the growth potential for algae and other

aquatic plants. 

environmental indicators: Scientific measurements that

track help measure over time the state of air, water, and land

resources, pressures on those resources, and resulting effects

on ecological condition and human health. Indicators show

progress in making the air cleaner and the water purer and in

protecting land. 

environmental tobacco smoke (ETS): A mixure of smoke

exhaled by a smoker and the smoke from the burning end of a

smoker’s cigarette, pipe, or cigar. Also known as secondhand

smoke.

erosion: The wearing away of land surface by wind or water,

intensified by land-clearing practices related to farming, residential or industrial development, road building, or logging. 

estuaries: Partially enclosed bodies of water (this term

includes bays, sounds, lagoons, and fjords); they are generally

considered to begin at the upper end of tidal or saltwater

influence and end where they meet the ocean. 

eutrophic: Pertaining to a lake or other body of water characterized by large nutrient concentrations, resulting in high

productivity of algae. 

eutrophication: The slow aging process during which a lake,

estuary, or bay evolves into a bog or marsh and eventually

disappears. During the later stages of this process, the water

body is choked by abundant plant life that result from higher

levels of nutritive compounds such as nitrogen and phosphorus. Human activities can accelerate the process. 

extraction waste: Byproducts produced as a result of mining

practices.

F

farmlands: Include both croplands lands used for production

of annual and perennial crops and livestock and on the surrounding landscape, which includes field borders and windbreaks, small woodlots, grassland or shrubland areas,

wetlands, farmsteads, small villages and other built-up areas,

and similar areas within and adjacent to croplands. 

fertilizers: Supplements to improve plant growth that are

commonly used on agricultural lands, as well as in urban,

industrial, and residential settings.

fish kill: A large-scale die-off of fish caused by factors such

as pollution, noxious algae, harmful bacteria, and hypoxic

conditions.

flora: Plant or bacterial life.

forage: Food for animals especially when taken by browsing

or grazing.

forests: Lands at least 10 percent covered by trees of any

size, at least one acre in extent. This includes areas in which

trees are intermingled with other cover, such as chaparral and

pinyon, juniper areas in the Southwest, and both naturally

regenerating forests and areas planted for future harvest

(plantations or tree farms). 

forest land: Land that is at least 10 percent stocked by forest trees of any size, including land that formerly had tree

cover and that will be naturally or artificially regenerated. The

minimum area for classification of forest land is one acre. 

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fresh water systems: Include: 

■ Rivers and streams, including those that flow only part of

the year 

■ Lakes, ponds, and reservoirs, from small farm ponds to the

Great Lakes 

■ Ground water, which is often directly connected to rivers,

streams, lakes, and wetlands 

■ Fresh water wetlands, including forested, shrub, and emergent wetlands (marshes), and open water ponds 

■ Riparian areas—the usually vegetated margins of streams

and rivers (although this term can also apply to lake margins). 

G

grasslands and shrublands: Lands in which the dominant

vegetation is grasses and other nonwoody vegetation, or

where shrubs (with or without scattered trees) are the norm

(also called rangelands); includes bare-rock deserts, alpine

meadows, arctic tundra, pastures, and haylands (an overlap

with the farmland system). Less-managed pastures and haylands fit well within the grassland/shrubland system; more

heavily managed ones fit well as part of the farmlands system. 

groundlevel ozone: See ozone.

ground water: Subsurface water that occurs beneath the

water table in soils and geologic formations that are fully saturated. 

H

habitat: The place where a population (e.g., human, animal,

plant, microorganism) lives and its surroundings, both living

and nonliving. 

hazardous waste: Byproducts of society that can pose a

substantial or potential threat to human health or the environment when improperly managed. Hazardous waste possesses at least one of four characteristics: ignitability,

corrosivity, reactivity, or toxicity.

health outcomes: An outcome measured by the quality of

life, likelihood of disease, life expectancy and overall health of

individuals or communities. 

heavy metals: Metallic elements with high atomic weights

(e.g., mercury, chromium, cadmium, arsenic, lead); can damage living things at low concentrations and tend to accumulate in the food chain.

herbicide: A form of pesticide used to control weeds that

limit or inhibit the growth of the desired crop.

high-level radioactive waste: Highly radioactive material

produced as a byproduct of the reactions that occur inside

nuclear reactors. High-level waste takes one of two forms:

spent (used) reactor fuel; waste materials remaining after

spent fuel is reprocessed. 

household hazardous waste: Hazardous products used and

disposed of by residential rather than industrial consumers. It

includes paints, stains, varnishes, solvents, pesticides, and

other materials or products containing volatile chemicals that

can catch fire, react, or explode, or are corrosive or toxic. 

hydrologic cycle: Movement or exchange of water between

the atmosphere and earth. 

hypoxia/hypoxic waters: Waters with low levels of dissolved

oxygen concentrations, typically less than two ppm, the level

generally accepted as the minimum required for most marine

life to survive and reproduce.

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I

impervious surface: A hard surface area that either prevents

or retards the entry of water into the soil mantle or causes

water to run off the surface in greater quantities or at an

increased rate of flow. Common impervious surfaces include,

but are not limited to, rooftops, walkways, patios, driveways,

parking lots, storage areas, concrete or asphalt paving, and

gravel roads. 

incidence rate of disease: The number of new cases of a disease or condition in a given period of time in a specified population.

indoor air: The breathable air inside a habitable structure or

conveyance. 

indoor air pollution: Chemical, physical, or biological contaminants in indoor air.

industrial waste: Process waste associated with manufacturing. This waste usually is not classified as either municipal

waste or hazardous waste by federal or state laws. 

industrial non-hazardous waste: Process waste associated

with generation of electric power and manufacture of materials such as pulp and paper, iron and steel, glass, and concrete.

This waste usually is not classified as either municipal waste

or hazardous waste by federal or state laws. 

infant mortality: The death of children in the first year of

life.

invasive species: See nonnative species.

K–L

land cover: The ecological status and physical structure of

the vegetation on the land surface. 

land use: Describes how a piece of land is managed or used

by humans. The degree to which the land reflects human

activities (e.g., residential and industrial development, roads,

mining, timber harvesting, agriculture, grazing, etc.).

landfills: 1. Sanitary landfills: Disposal sites for nonhazardous

solid wastes spread in layers, compacted to the smallest practical volume, and covered by material applied at the end of

each operating day. 2. Secure chemical landfills: Disposal sites

for hazardous waste, selected and designed to minimize the

chance of release of hazardous substances into the environment.

landscape: The traits, patterns, and structure of a specific

geographic area, including its biological composition, its

physical environment, and its anthropogenic or social patterns. An area where interacting ecosystems are grouped and

repeated in similar form. 

landscape condition: The extent, composition, and pattern

of habitats in a landscape.

large urban built-up areas: A National Resources Inventory

land cover/use category composed of developed tracts of at

least 10 acres, meeting the definition of urban and built-up

areas.

leaching: The process by which soluble materials in the soil,

such as nutrients, pesticide chemicals, or contaminants, are

washed into a lower layer of soil or are dissolved and carried

away by water. 

lead: A heavy metal used in many materials and products. It is

a natural element and does not break down in the environD-8
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ment. When absorbed into the body, it can be highly toxic to

many organs and systems.

levee: A natural or manmade earthen barrier along the edge

of a stream, lake, or river. Land alongside rivers can be protected from flooding by levees.

lichen: Any of numerous complex thallophytic plants made up

of an alga and a fungus growing in symbiotic association on a

solid surface (e.g., a rock). 

life expectancy: The probable number of years (or other

time period) that members of a particular age class of a population are expected to live, based on statistical studies of

similar populations in similar environments. 

life expectancy (at birth): The average number of years that

a group or cohort of infants born in the same year are

expected to live.

low birth weight: Refers to children born weighing less than

2,500 grams (5.5 pounds).

low-level waste: Radioactive waste, including accelerator produced waste, that is not high-level radioactive waste, spent

nuclear fuel, transuranic waste, byproduct material (as defined

in the Atomic Energy Act of 1954), or naturally occurring

radioactive material. 

M

media: Specific environments—air, water, soil—that are the

subject of regulatory concern and activities. 

medical waste: Any solid waste generated during the diagnosis, treatment, or immunization of human beings or animals, in

research, production, or testing. 

mercury: A metallic element that occurs in many forms and in

combination with other elements. When combined with carbon, which readily occurs in water, it forms more bioavailable

organic mercury compounds (e.g., methylmercury).

metabolites: Compounds that result from human digestion

(metabolism) of contaminants and that serve as a biomarkers

of exposure. 

microorganisms: Tiny life forms that can be seen only with

the aid of a microscope. Some microorganisms can cause

acute health problems when consumed; also known as

microbes. 

mobile sources: Moving objects that release pollution from

combustion of fossil fuels, such as cars, trucks, buses, planes,

trains, lawn mowers, construction equipment, and snowmobiles. Some mobile sources, such as some construction equipment or movable diesel generators, are called nonroad

sources, because they are usually operated off road. 

morbidity: Sickness, illness, or disease that does not result in

death.

mortality: Death rate. 

mortality rate: The proportion of the population who die of

a disease, often expressed as a number per 100,000.

municipal solid waste: Waste discarded by households,

hotels/motels, and commercial, institutional, and industrial

sources. It typically consists of everyday items such as product packaging, grass clippings, furniture, clothing, bottles,

food scraps, newspapers, appliances, paint, and batteries. It

does not include waste water.

N

National Ambient Air Quality Standards: Standards established by EPA under the Clean Air Act that apply to outdoor

air throughout the country. See criteria pollutants. 

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nonpoint source pollution: Pollution that occurs when rainfall, snowmelt, or irrigation water runs over land or through

the ground, picks up pollutants, and deposits them into

rivers, lakes, coastal waters, or ground water. Types of pollution include sediments, nutrients, pesticides, pathogens (bacteria and viruses), toxic chemicals and heavy metals that

runoff from agricultural land, urban development, and roads. 

nutrient: Any substance assimilated by living things that promotes growth. The term is generally applied to nitrogen and

phosphorus, but is also applied to other essential and trace

elements. 

nutrient enrichment: See eutrophication.

O

oil and gas production wastes: Drilling fluids, produced

waters, and other wastes associated with the exploration,

development, and production of crude oil or natural gas that

are conditionally exempted from regulation as hazardous

wastes. 

organic matter: Plant and animal material that is in the

process of decomposing. When it has fully decomposed, it is

called “humus.” This humus is important for soil structure

because it holds individual mineral particles together in clusters. 

organophosphate: Pesticides that contain phosphorus;

shortlived, but some can be toxic when first applied. 

ozone: A very reactive form of oxygen that is a bluish irritating gas of pungent odor. It is formed naturally in the atmosphere by a photochemical reaction and is a beneficial

component of the upper atmosphere. It is also a major air

pollutant in the lower atmosphere, where it can form by photochemical reactions when there are conditions of air pollutants, bright sunlight, and stagnant weather.

nitrate: The primary chemical form of nitrogen in most

aquatic systems; occurs naturally; a plant nutrient and fertilizer; can be harmful to humans and animals.

nitric oxide (NO): A gas formed by combustion under high

temperature and high pressure in an internal combustion

engine; it is converted by sunlight and photochemical

processes in ambient air to nitrogen oxide. NO is a precursor

of ground level ozone pollution, or smog. 

nitrogen dioxide (NO2): The result of nitric oxide combining with oxygen in the atmosphere; major component of photochemical smog. 

nitrogen oxides (NOX): The result of photochemical reactions of nitric oxide in ambient air; major component of photochemical smog. Product of combustion from transportation

and stationary sources and a major contributor to the formation of ozone in the troposphere and to acid deposition.

non-community water system: A public water system that is

not a community water system. Nontransient noncommunity

water systems are those that regularly supply water to at

least 25 of the same people at least six months per year but

not year-round (e.g., schools, factories, office buildings, and

hospitals that have their own water systems). Transient noncommunity water systems provide water in a place where people do not remain for long periods of time (e.g., a gas station

or campground).

non-hazardous waste: See solid waste.

non-isolated intermediaries: An intermediate compound in

a chemical manufacturing process that can be a by-product

or can be released as a result of the process.

nonnative species: A species that has been introduced by

human action, either intentionally or by accident, into areas

outside its natural geographical range. Other names for these

species include alien, exotic, introduced, and nonindigenous. 

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ozone depletion: Destruction of the stratospheric ozone

layer, which shields earth from ultraviolet radiation harmful to

life. This destruction of ozone is caused by the breakdown of

certain compounds that contain chlorine, bromine, or both

(chlorofluorocarbons or halons), which occurs when they

reach the stratosphere and then catalytically destroy ozone

molecules. 

ozone hole: A well-defined, large-scale area of significant

thinning of the ozone layer. It occurs over Antarctica each

spring. 

ozone layer: The protective stratum in the atmosphere,

about 15 miles above the ground, that absorbs some of the

sun’s ultraviolet rays, thereby reducing the amount of potentially harmful radiation that reaches earth’s surface. 

ozone precursors: Chemicals that contribute to the formation of ozone.

P

particulate matter: Solid particles or liquid droplets suspended or carried in the air (e.g., soot, dust, fumes, mist). 

passive smoking: Exposure to tobacco smoke, or the chemicals in tobacco smoke, without actually smoking. It usually

refers to a situation where a nonsmoker inhales smoke emitted into the environment by other people smoking. This

smoke is known as “environmental tobacco smoke” (ETS). 

pastureland: A National Resources Inventory land cover/use

category of land managed primarily for the production of

introduced forage plants for livestock grazing. Pastureland

cover may consist of a single species in a pure stand, a grass

mixture, or a grass-legume mixture. For the NRI, it includes

land that has a vegetative cover of grasses, legumes, and/or

forbs, regardless of whether or not it is being grazed by livestock. 

pathogen: Microorganism (e.g., bacteria, viruses, or parasites) that can cause disease in humans, animals, and plants.

persistent organic pollutants: Chemicals that endure in the

environment and bioaccumulate as they move up trough the

food chain. They include organochlorine pesticides, polychlorinated biphenyls (PCBs), dioxins, and furans.

pesticides: Any substance or mixture of substances intended

to prevent, destroy, repel, or mitigate any pest. Pests can be

insects, mice and other animals, unwanted plants (weeds),

fungi, or microorganisms such as bacteria and viruses. Though

often misunderstood to refer only to insecticides, the term

“pesticide” also applies to herbicides, fungicides, and various

other substances used to control pests. Under U.S. law, a

pesticide is also any substance or mixture of substances

intended for use as a plant regulator, defoliant, or desiccant. 

phosphorus: An essential chemical food element that can

contribute to the eutrophication of lakes and other water

bodies. Increased phosphorus levels result from discharge of

phosphorus containing materials into surface waters. 

photosynthesis: The manufacture by plants of carbohydrates

and oxygen from carbon dioxide mediated by chlorophyll in

the presence of sunlight. 

phytoplankton: That portion of the plankton community

composed of tiny plants (e.g., algae, diatoms). 

PM2.5: Fine particles that are less than or equal to 2.5

micrometers in diameter.

PM10: Particles less than or equal to 10 micrometers in diameter.

point source pollution: Effluent or discharges directly from a

pipe into a waterway (e.g., from many industries and sewage

treatment plants).

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pollutant: Generally, any substance introduced into the environment that adversely affects the usefulness of a resource or

the health of humans, animals, or ecosystems. 

pollution: Generally, the presence of a substance in the environment that, because of its chemical composition or quantity, prevents the functioning of natural processes and

produces undesirable environmental and health effects. Under

the Clean Water Act, for example, the term has been defined

as the manmade or man-induced alteration of the physical,

biological, chemical, and radiological integrity of water and

other media.

polychlorinated biphenyls (PCBs): A group of synthetic

chemicals that can exist as oily liquids and waxy solids. They

have been commercially used in electrical transformers and

capacitors, hydraulic equipment, paint elasticizers, plastics,

rubber products, pigments, dyes, and carbonless copy paper.

PCBs can produce toxic effects and are probable carcinogens.

pressure: See stressor.

prevalence of disease: That part of the total population

affected by a condition or disease.

production capacity: Chlorophyll per unit area for terrestrial

ecosystems (including wetlands and riparian areas) and per

unit volume for aquatic ecosystems.

productivity: The rate at which ecosystems use energy (principally solar energy) to fix atmospheric carbon dioxide. 

R

radioactive waste: Garbage, refuse, sludge, and other discarded material, including solid, liquid, semisolid, or contained

gaseous material that must be managed for its radioactive

content. Types of radioactive waste include high-level waste,

spent nuclear fuel, transuranic waste, low-level waste, mixed

lowlevel waste, and contaminated media.

radon (Rn-222): A naturally occurring radioactive gas that

has no color, odor, or taste and is chemically inert. Radon

comes from the radioactive decay of uranium in soil, rock, and

ground water and is found all over the U.S. It has a half-life of

3.8 days, emitting ionizing radiation (alpha particles) during

its radioactive decay to several radioactive isotopes known as

“radon decay products.” It gets into indoor air primarily from

soil under homes and other buildings. Radon is a known

human lung carcinogen and represents the largest fraction of

the public’s exposure to natural radiation.

rangelands: A National Resources Inventory land cover/use

category on which the climax or potential plant cover is composed principally of native grasses, grasslike plants, forbs or

shrubs suitable for grazing and browsing, and introduced forage species that are managed like rangeland. This would

include areas where introduced hardy and persistent grasses,

such as crested wheatgrass, are planted and such practices as

deferred grazing, burning, chaining, and rotational grazing are

used, with little or no chemicals or fertilizer being applied.

Grasslands, savannas, many wetlands, some deserts, and tundra are considered to be rangeland. Certain communities of

low forbs and shrubs, such as mesquite, chaparral, mountain

shrub, and pinyon-juniper, are also included as rangeland. 

rare and at-risk species: Rare species are those that are particularly vulnerable to both human-induced threats and natural fluctuations and hazards. At-risk species are those

classified by the Association for Biodiversity Information as

vulnerable or more rare.

RCRA hazardous waste: Applies to certain types of hazardous wastes that appear on EPA’s regulatory listing (RCRA)

or that exhibit specific characteristics of ignitability, corrosiveness, reactivity, or excessive toxicity.

remediation: Cleanup or other methods used to remove or

contain a toxic spill or hazardous materials from a contaminated site. 

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risk: The probability that a health problem, injury, or disease

will occur. 

risk factor: A characteristic (e.g., race, sex, age, obesity) or

variable (e.g., smoking, occupational exposure level) associated with increased probability of an adverse effect. 

runoff: That part of precipitation, snowmelt, or irrigation

water that runs off the land into streams or other surface

water. It can carry pollutants from the air and land into receiving waters. 

rural transportation land: A National Resources Inventory

land cover/use category that consists of all highways, roads,

railroads, and associated right-of-ways outside urban and

built-up areas; including private roads to farmsteads or ranch

headquarters, logging roads, and other private roads, except

field lanes.

S

secondhand smoke: See environmental tobacco smoke.

sedimentation: The process of forming or depositing sediment; letting solids settle out of wastewater by gravity during

treatment. 

sludge: Solid, semisolid, or liquid waste generated from a

municipal, commercial, or industrial wastewater facility. 

small built-up areas: A National Resources Inventory land

cover/use category consisting of developed land units of

0.25 to 10 acres, which meet the definition of urban and

built-up areas.

solid waste: Nonliquid, nonsoluble materials ranging from

municipal garbage to industrial wastes that contain complex

and sometimes hazardous substances. Solid wastes also

D-13

include sewage sludge, agricultural refuse, demolition wastes,

mining residues, and liquids and gases in containers.

species richness: The absolute number of species in an

assemblage or community.

spent nuclear fuel: Nuclear reactor fuel that has been used

to the extent that it can no longer effectively sustain a chain

reaction. 

spray drift: The physical movement of a pesticide through air

at the time of application, or soon thereafter, to any site

other than that intended for application.

stationary source: A place or object from which pollutants

are released and that stays in one place. These sources

include many types of facilities, including power plants, gas

stations, dry cleaners, incinerators, factories, and houses.

stressor: A physical, chemical, or biological entity that can

induce adverse effects on ecosystems or human health.

submerged aquatic vegetation (SAV): Rooted vegetation

that grows under water in shallow zones where light penetrates. 

Superfund: The program operated under the legislative

authority of the Comprehensive Environmental Response,

Compensation, and Liability Act (CERCLA) and the Superfund

Amendments and Reauthorization Act (SARA) that funds and

carries out EPA solid waste emergency and long-term removal

and remedial activities. These activities include establishing

the National Priorities List, investigating sites for inclusion on

the list, determining their priority, and conducting and/or

supervising cleanup and other remedial actions. 

Superfund site: Any land in the U.S. that has been contaminated by hazardous waste and identified by EPA as a candidate for cleanup because it poses a risk to human health, the

environment, or both. 
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U

ultraviolet (UV) radiation: Radiation from the sun that can

be useful or potentially harmful. UV radiation from one part

of the spectrum (UV-A) enhance plant life. UV radiation from

other parts of the spectrum (UV-B) can cause skin cancer or

other tissue damage. The ozone layer in the atmosphere

partly shields the earth from UV radiation reaching the surface. 

underground storage tanks: Tanks and their underground

piping that have at least 10 percent of their combined volume

underground.

urban and built-up areas: A National Resources Inventory

land cover/use category consisting of residential, industrial,

commercial, and institutional land construction sites; public

administrative sites; railroad yards; cemeteries; airports; golf

courses; sanitary structures and spillways; small parks (less

than 10 acres) within urban and built-up areas; and highways,

railroads, and other transportation facilities if they are surrounded by urban areas. Also included are tracts of less than

10 acres that do not meet the above definition but are completely surrounded by urban and builtup land. 

urban and suburban areas: Places where the land is primarily devoted to buildings, houses, roads, concrete, grassy lawns,

and other elements of human use and construction. Urban

and suburban areas, in which about three-fourths of all

Americans live, span a range of density, from the city center

characterized by high-rise buildings and little green space to

the suburban fringe where development thins to a rural landscape. This definition does not include all developed lands,

for example, small residential zones, the area of rural interstate highways, farmsteads, and the like, which are developed

but are not sufficiently built-up to be considered urban or

suburban. 

urbanization: The concentration of development in relatively

small areas (cities and suburbs). The U.S. Census Bureau

D-14

surface water: Water in rivers, streams, lakes, ponds, reservoirs, estuaries, and wetlands (found at the surface, in contrast to ground water).

T

threatened and endangered species: Those species that

are in danger of extinction throughout all or a significant portion of their range or are likely to become endangered in the

future. 

threshold: 1.The lowest dose of a chemical at which a specified measurable effect is observed and below which it is not

observed. 2.The dose or exposure level below which a significant adverse effect is not expected. 

timber land: Forest land that is capable of producing crops

of industrial wood (at least 20 cubic feet per acre per year in

natural stands) and not withdrawn from timber use by statute

or administrative regulation. 

Toxics Release Inventory (TRI): A publicly available EPA

database that contains information on toxic chemical releases

and other waste management activities reported annually by

certain covered industries and federal facilities. TRI was

established under the Emergency Planning and Community

Right-to-Know Act of 1986 (EPCRA) and expanded by the

Pollution Prevention Act of 1990. 

toxic substance: Any substance that presents a significant

risk of injury to health or the environment through exposure.

toxic waste: A waste that can produce injury if inhaled, swallowed, or absorbed through the skin. 

troposphere: The layer of the atmosphere closest to the

earth’s surface. 
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EPA’s Draft Report on the Environment 2003

defines “urban” as areas with densities of people greater than

1.5 people per acre.

V-Z

vehicle miles traveled: A measure of the extent of motor

vehicle operation; the total number of vehicle miles traveled

by all vehicles within a specific geographic area over a given

period of time. Vehicle miles traveled and other variables are

used to estimate air pollutant emissions. 

volatile organic compounds: Chemicals, such as gasoline

and perchloroethylene (a dry cleaning solvent) that contain

carbon and vaporize readily. 

waste minimization priority chemicals: A group of 30

chemicals—3 metals (lead, mercury, and cadmium) and 27

organic chemicals—identified as the highest priority for

reduction in industrial and hazardous waste.

water clarity: A measure of how clear a body of water is;

measured in the distance light penetrates into the water.

water quality criteria: Levels of water quality expected to

render a body of water suitable for its designated use.

Criteria are based on specific levels of pollutants that would

make the water harmful if used for drinking, swimming, irrigation, fish production, or industrial processes. 

water quality standards: State-adopted and EPA-approved

ambient standards for water bodies. The standards define the

water quality goals of a water body by designating the uses

of the water and setting criteria to protect those uses. The

standards protect public health and welfare, enhance the

quality of the water, and provide the baseline for surface

water protection under the Clean Water Act.

waterborne disease outbreak: The significant occurrence of

acute illness associated with drinking water from a public

water system or exposure encountered in recreational or

occupational settings as determined by appropriate local or

state agencies. (The Centers for Disease Control and

Prevention defines an outbreak as two or more cases associated with drinking water as the route of exposure.) 

watershed: An area of land from which all water that drains

from it flows to a single water body.

wetland ecosystems: Areas that are inundated or saturated

by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do

support, a prevalence of vegetation typically adapted for life

in saturated soil conditions. Wetlands generally include

swamps, marshes, bogs, and similar areas.

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Appendix D - Glossary of Terms

EPA’s Draft Report on the Environment 2003

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Appendix E - 

Sources for Environmental

Protection in Context
Appendix E - Sources for Environmental Protection in Context

EPA’s Draft Report on the Environment 2003

E-2

People

National Oceanic and Atmospheric Administration. NOAA Backgrounder “Working for America’s Coasts: An Introduction to the

National Ocean Service.” January 2002. (February 25, 2003; http://www.publicaffairs.noaa.gov/grounders/pdf/nos.pdf).

Pastor, P.N., D.M. Makuc, C. Reuben, H. Xia, et al. Chartbook on Trends in the Health of Americans. Health, United States, 2002,

Hyattsville, MD: National Center for Health Statistics, 2002.

U.S. Census Bureau. Statistical Abstract of the United States 2001: The National Data Book. Washington, DC: U.S. Census Bureau,

2001.

Water Resources

Dahl, T.E. Status and Trends of Wetlands of the Conterminous United States 1986 to 1997, Washington, DC: U.S. Department of the

Interior, U.S. Fish and Wildlife Service, 2000.

Dahl, T.E. Wetland Losses in the United States 1780’s to 1980’s, Washington, DC: U.S. Department of the Interior, U.S. Fish and

Wildlife Service, 1990.

Environment Canada and U.S. Environmental Protection Agency. The Great Lakes: An Environmental Atlas and Resource Book,

Toronto, Ont: Government of Canada and Chicago, IL: U.S. Environmental Protection Agency, 1995.

U.S. Environmental Protection Agency. National Water Quality Inventory: 1998 Report to Congress, EPA-841-R-00-001.

Washington, DC: U.S. Environmental Protection Agency, Office of Water, June 2000.

U.S. Geological Survey. Strategic Directions for the U.S. Geological Survey Ground-Water Resources Program, A Report to Congress,

Reston, VA: U.S. Geological Survey, November 30, 1998.

Energy and Economy

Marlowe, Howard. Assessing The Economic Benefits Of America’s Coastal Regions. October 2000. (February 25, 2003;

http://oceanservice.noaa.gov/website/retiredsites/natdia_pdf/13marlowe.pdf)

U.S. Department of Commerce, Bureau of Economic Analysis. GDP and Other Major NIPA Series, 1929-2002:1. August 2002.

(February 25, 2003; http://www.bea.gov/bea/ARTICLES/2002/08August/0802GDP_&Other_Major_NIPAs..pdf).

U.S. Department of Energy, Energy Information Administration. Annual Energy Review 2001. December 2002. 

(February 25, 2003; http://www.eia.doe.gov/emeu/aer/overview.html).

U.S. Environmental Protection Agency. Latest Findings on National Air Quality: 2001 Status and Trends, EPA-454-K-02-001.

Washington, DC: U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, September 2002.
Appendix E - Sources for Environmental Protection in Context

EPA’s Draft Report on the Environment 2003

Land Use

The H. John Heinz III Center for Science, Economics and the Environment. The State of the Nation’s Ecosystems: Measuring the

Lands, Waters, and Living Resources of the United States, New York, NY: Cambridge University Press, September 2002.

U.S. Census Bureau. Statistical Abstract of the United States 2001: The National Data Book, Washington, DC: U.S. Census Bureau,

2001.

U.S. Department of Agriculture, Forest Service. Draft Resource Planning and Assessment Tables. August 2002. (September

2003; http://www.ncrs.fs.fed.us/4801/FIADB/rpa_tabler/Draft_RPA_2002_Forest_Resource_Tables.pdf)

U.S. Department of Agriculture, Forest Service. U.S. Forest Facts and Historical Trends, Brochure #FS-696, Washington, DC: U.S.

Department of Agriculture, April 2001.

U.S. Department of Agriculture, Natural Resources Conservation Service. Summary Report: 1997 National Resources Inventory

(Revised, December 2000). Washington, DC: Natural Resources Conservation Service and Ames, Iowa: Iowa State University,

Statistical Laboratory. December 1999, revised December 2000.

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Appendix E - Sources for Environmental Protection in Context

EPA’s Draft Report on the Environment 2003

E-4