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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 20460
OFFICE OF
RESEARCH AND DEVELOPMENT
The U.S. Environmental Protection Agency's (EPA) success is dependent, in large part, on our
ability to make credible environmental decisions based on solid scientific and technical
information. EPA's Office of Research and Development (ORD) is dedicated to developing
quality science that is supportive of the Agency's mission and makes an impact on decision-
making. ORD has produced this Research Accomplishments Report to inform stakeholders and
the interested public of the significant research that was accomplished during the period 1999
through 2001. It is not meant to provide an exhaustive list of our work, but rather to acquaint
you with the broad range of meaningful scientific and technical contributions that are produced
by the Agency's research laboratories and centers.
We are particularly proud of the expertise and personal commitment that ORD's scientists,
engineers, and administrative personnel bring to addressing the environmental challenges of
today and tomorrow. ORD's researchers continue to be on the leading edge of scientific inquiry -
expanding our nation's scientific knowledge about the environment, developing guidance for
assessing both human and ecological risks, devising new technologies and risk management
approaches to both prevent and mitigate pollution, and providing technical assistance to those
working to protect our environment. All of'our work is guided by sound scientific principles,
including independent peer review, to ensure that our contributions are consistently of the highest
quality.
I hope that you will take the time to read about EPA's efforts to better understand the complex
scientific and technical issues facing our nation's environment in this new century. We in ORD
remain committed to applying our creativity and technical expertise in helping the Agency meet
its vital mission of protecting public health and the environment.
Paul Oilman, Ph.D.
Assistant Administrator
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Table of Contents
11
41
51
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upon which lire depends."The Office of
Research andlDeveldpment (ORD), EPA's
principal scientific and research arm, conducts
research to provide the best available scientific
information for environmental decision making.
ORD's mission is to conduct leading-edge
research and foster the sound use of science and
technology to fulfill EPA's mission.
the _"risk paradigm," which consists o£two,_ - ^
interrelated phases, risk" assessment "and risk „
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management Risk assessment is the process
used to evaluate the degree and probability of
harm to human health and the environment
from such stressors as pollution or habitat loss.
The risk assessment process consists of exposure
assessment, hazard identification, dose-response
assessment, and risk characterization. Risk
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NCEA National Center for Environmental Assessment
NCER National Center for Environmental Research
NERL National Exposure Research Laboratory
NHEERL National Health and Environmental Effects Research Laboratory
NRMRL National Risk Management Research Laboratory
management involves determining whether and
how risks from stressors should be managed or
reduced. It is based on the risk assessment
findings and public health, social, economic
and other factors. Risk management options
include pollution prevention and/or control
technologies to reduce or eliminate the
pollutant or other stressor in the environment.
ORD RESEARCH
The nature of ORD research is ongoing;
individual projects provide small but important
pieces of larger puzzles, and subsequent projects
build on earlier work. Therefore, research
"accomplishments" include initiation of long-
term, research programs and intermediate
milestones that are reached along the way to
major organizational goals. While by no means
all-inclusive, the research highlighted in this
document illustrates our recent key
accomplishments.
The organization of this report is based on
the high-priority research areas identified in the
1997 Update to ORD's Strategic Plan. The six
highest priority areas are safe drinking water,
high-priority air pollutants, emerging
environmental issues, ecosystem risk assessment,
human health risk assessment, and pollution
prevention and new technologies. Other
important areas of research at ORD are global
change, ecosystem water quality, tropospheric
ozone, air toxics, environmental monitoring,
contaminated sites, and exposures to pesticides
and toxic substances. Research
accomplishments from all these areas are
incorporated into the chapters of this report.
ORD LABORATORIES AND CENTERS
ORD is organized into three national
laboratories and two national centers located in
facilities around the country, with headquarters
in Washington, DC. All ORD labs and centers
provide information and technical support to,
and collaborate with, EPA Program Offices,
Regions, state/municipal/tribal governments,
and other agencies performing environmental
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research, assessment, and risk management.
ORD scientists also collaborate with private-
sector partners to address specific environmental
issues.
The National Exposure Research
Laboratory (NERL) provides information and
tools to reduce the uncertainty in EPA's
exposure and risk assessments for factors that
stress the environment, including chemicals,
living organisms, radiation, changes in land and
water use, and changes in climate. NERL also
evaluates innovative exposure assessment
technologies and provides information on
stressor sources, pollutant transport and fate,
and human exposure to pollutants.
The National Health and Environmental
Effects Research Laboratory (NHEERL) is
EPA's focal point for scientific research on the
effects of contaminants and environmental
stressors on human health and ecosystem
integrity. NHEERL's research is used by EPA and
other government agencies to identify and
understand the processes that affect our health
and environment, as well as to evaluate the risks
that pollution poses to humans and ecosystems.
The National Risk Management Research
Laboratory (NRMRL) conducts research on the
means to prevent and reduce risks from
pollution that threaten human health and the
environment. NRMRL investigates methods for
prevention and control of pollution to air, land,
and water; protection of water quality in public
water systems; cleanup of contaminated sites,
sediments, and groundwater; prevention and
control of indoor air pollution; and restoration
of ecosystems.
The National Center for Environmental
Assessment (NCEA) is EPA's national resource
center for human health and ecological risk
assessment. NCEA develops risk assessments,
conducts research to improve the science of risk
assessment, and provides guidance and support
to risk assessors.
NCEA functions as a
critical link between
researchers and EPA
decision makers.
The National
Center for
Environmental
Research (NCER)
supports leading-edge environmental research
by scientists in the academic community.
NCER's Science to Achieve Results (STAR)
program funds competitive research grants and
graduate fellowships in numerous
environmental science and engineering
disciplines to complement ORD's in-house
research. Through this same competitive
process, NCER periodically establishes research
centers at academic institutions to address
specific topics of national concern.
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The American public enjoys safe drinking
water because public utilities and other drinking
water providers
• select the. best available sources and protect
them from contamination;
• use water treatment, including disinfection, to
control contaminants; and
• prevent water quality deterioration in the
distribution system.
In the United States, these practices have
virtually eliminated waterborne threats such as
typhoid fever and cholera; however, some public
health concerns remain. Waterborne disease
Under the Safe Drinking Water Act, EPA
conducts research that provides a strong
scientific foundation for standards that limit the
public's exposure to drinking water
contaminants. EPA's drinking water research
program supports major regulatory activities
including the Arsenic Rule, the Microbial/
Disinfection Byproduct Rules, and future
decisions on unregulated waterborne pathogens
and chemicals. ORD is conducting research on
waterborne pathogens (e.g., Cryptosporidium and
Norwalk virus), arsenic, disinfection byproducts
and other chemical contaminants to support
outbreaks caused by pathogenic bacteria,
viruses, and parasites continue to be reported
periodically, demonstrating that the safety of
drinking water can still be compromised if
treatment is inadequate. Surface water and
groundwater sources can be contaminated with
many different types of chemical contaminants,
including natural (e.g., arsenic) and manmade
(e.g., pesticides) substances. Furthermore, the
disinfection process itself creates a number of
potentially toxic chemical byproducts. Some
groups such as infants, children, and people with
weakened immune systems are known to be
particularly sensitive to certain waterborne
pathogens and chemicals.
EPA's decision-making process. Recent research
accomplishments to protect drinking water
quality are highlighted in this chapter.
ARSENIC MODE OF ACTION
Inorganic arsenic occurs naturally in soil
and groundwater in certain parts of the United
States, particularly those with volcanic activity
or hot springs. People ingesting high levels of
arsenic may experience health problems such as
cardiovascular disease, strokes, peripheral
neuropathy (a disorder of the nerves), diabetes,
abnormal fetal development, and several types
of cancer. While studies in foreign countries
with very high levels of arsenic in drinking
water have demonstrated that arsenic can be
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harmful, the actual
mechanisms by which
health problems occur
are not well understood.
Research on specific
ways that arsenic affects
the body can provide
important information
for estimating the risk of
arsenic, particularly at the low levels of exposure
found in some areas of the United States.
A team of ORD scientists, collaborating
with researchers at the University of North
Carolina at Chapel Hill, NC, and the
University of British Columbia in Vancouver,
Canada, studied the effects of several forms of
arsenic on isolated DNA and on DNA in
cultured human lymph cells. The researchers
found that some arsenic metabolites caused
direct damage to DNA in both test settings.
This finding is significant because it had been
Preparing water samples for toxic element analysis.
assumed that compounds
produced during arsenic
metabolism were less toxic
than arsenic itself. Also,
prior to this research, there
was little evidence that
arsenic interacted with
DNA, which had led
scientists to believe that
arsenic caused cancer through indirect
mechanisms. The results of this study support
the hypothesis that arsenic may be able to cause
cancer by interacting directly with DNA.
These findings provide a strong impetus for
additional studies on arsenic's mode of action
and the role of metabolism in the development
of cancer and other toxic effects. This new
information will improve the scientific
foundation for risk assessments conducted in
support of future regulatory reviews of EPA's
standard for arsenic in drinking water.
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As fragments of damaged DNA migrate in the electric field created in this single-cell gel assay, they produce
the appearanceof the tail of a comet. These images are representative of those seen in (A) control and
pentavalent methyl arsenic compounds, no DNA damage; (B)trivalent methyl arsenic, some DNA damage;
and (C) even very low concentrations of trivalent dimethyl arsenic, appreciable DNA damage,
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DISINFECTION BYPRODUCTS
ORD scientists are using innovative
analytical techniques to learn more about the
chemistry of several disinfectants that are being
increasingly used by water utilities as
alternatives to the standard treatment product,
chlorine. These alternative disinfectants, which
include ozone, chlorine dioxide, and
chloramine, may be used either alone or in
combination with chlorine. Alternative
disinfectants are popular in the United States
because they destroy harmful microorganisms
while allowing treatment plants to more easily
comply with EPA regulations that limit levels of
potentially harmful compounds in drinking
water. Compared to chlorine, alternative
disinfectants typically produce lower levels of
potentially harmful byproducts. However, there
is concern that these new treatments may
produce previously unrecognized, potentially
harmful byproducts.
Using various laboratory techniques, ORD
scientists have identified many new disinfection
byproducts from drinking water treated with
single disinfectants or with combinations of two
or more disinfectants. In treatments using only
one chemical at a time, chlorine dioxide and
ozone produced the least number of potentially
harmful byproducts, whereas chlorine and
chloramine produced many potentially harmful
byproducts. Of the disinfectants tested, chlorine
produced the highest overall concentrations of
potentially harmful byproducts.
Disinfection byproducts
are formed when a
disinfectant such as chlorine
or ozone is used to destroy
harmful microorganisms in
drinking water.
The drinking water in some communities
contains bromine compounds. There is some
evidence from laboratory studies that high doses
of bromine-containing compounds may be more
harmful than chlorine-containing compounds in
some situations. Therefore, ORD scientists
extended their research on disinfection
byproducts to examine byproducts produced
when source waters contain relatively high
concentrations of bromine. They found that
elevated bromine levels caused a shift from
chlorinated to brominated disinfection
byproducts. More research is needed to clarify
Electron micrograph ofGiardia,
a water-borne disease-causing
microorganism.
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what, if any, public health risks may accompany
the presence of brominated disinfection
byproducts in drinking water.
In a related effort, scientists from ORD,
the University of North Carolina, and the
Metropolitan Water District of Southern
California are conducting a Nationwide
Occurrence Study of disinfection byproducts.
A multidisciplinary group of experts ranked
more than 500 disinfection byproducts
according to predicted health problems.
The 50 "highest priority" disinfection
byproducts are being measured in the drinking
water of U. S. communities. More chemicals are
being added to the list as they are identified as
potentially hazardous byproducts. The results of
this study will help focus future health effects
research, with the ultimate goal of minimizing
hazardous byproducts and keeping drinking
water as safe as possible for consumers.
IVITBE IN GROUNDWATER
In different areas of the country, methyl
tert-butyl ether (MTBE) is added to gasoline
either to reduce emissions that cause ground-
level ozone or to enhance octane. If
underground storage tanks leak or gasoline
spills,
groundwater
can be
contaminated
with MTBE,
adversely
affecting the
taste and odor of drinking water. Although
MTBE is considered to be a potential human
carcinogen at high doses, the potential health
risks of exposure to MTBE at low levels in
drinking water have not been determined.
rBiodegradation is the
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Breakdown of chemicals by
microorganisms
An important area of EPA research has been
to develop various technological approaches for
reducing MTBE in the environment to levels
that are acceptable from both aesthetic and
public health perspectives. Monitored Natural
Attenuation is one of the innovative
technologies that EPA is evaluating.
Monitored Natural Attenuation relies on
the natural processes of dilution, dispersion,
sorption, and biodegradation to reduce the
concentration, mass, mobility, and toxicity of
contaminants in soil over a reasonable time
period. After reviewing existing research on
Monitored
Natural
Attenuation,
EPA's
Science
Advisory
Board
I recommended
8
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that the Agency investigate how well MTBE
and other fuel additives biodegrade under
various field conditions. ORD researchers
collaborated with industry scientists to evaluate
the biodegradation of MTBE at 74 gasoline
service stations in the eastern United States.
The scientists determined that natural
biodegradation limits the spread of MTBE
contamination at many underground storage
tank sites. They also learned that measuring
some geochemical parameters (e.g., sulfate,
methane) in water samples from monitoring
wells will help identify sites where
biodegradation can effectively limit the spread
of MTBE and other contaminants.
LOOKING TO THE FUTURE
A few anticipated milestones in ORD's
Drinking Water research program include
* risk assessments for selected waterbome
pathogens and chemicals on EPA's
Contaminant Candidate List of unregulated
contaminants,
* information on potential associations between
exposure to disinfection byproducts in drinking
water and reproductive problems, and
• cost-effective technologies for removing arsenic
from drinking water.
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ORD's water research program furnishes the
tools used by EPA's Office of Water to protect
the Nation's freshwater and coastal resources.
ORD also develops tools and techniques to
assess damage to aquatic systems; identify the
sources of the damage; and forecast the
ecological, human health, and economic
outcomes of alternative solutions to water
quality problems. ORD also investigates
methods to clean up contaminated sites,
including those with contaminated groundwater
and contaminated sediments.
modeling system, scientists and water resource
managers will be able to identify the sources and
relative contributions of sediments and
nutrients to Lake Tahoe. In addition, resource
managers will be able to determine how much
these inputs to the lake must be reduced to
attain the desired water clarity.
The sediment transport model, which is one
component of the complete system, simulates
soil erosion and the movement of sediment and
nutrients from surrounding watersheds into Lake
Tahoe. This model predicts how changes in land
This chapter presents a diverse sampling of
recent accomplishments by ORD scientists who
are studying ways to preserve and restore the
quality of the Nation's water resources.
MODELING WATER QUALITY
Water quality in Lake Tahoe in California,
including the lake's remarkable water clarity,
has been deteriorating since the 1960s. ORD
awarded scientists at the University of
California-Davis a grant to study how soil
erosion and pollutant transport from the
surrounding land area affect the lake. The
researchers developed a series of integrated
computer models to simulate sediment and
nutrient transport and other factors affecting
water clarity. Equipped with this computer
surface/vegetation cover (e.g., roads,
urbanization, and forest practices) may affect
the water, sediment, and nutrient balances in
Lake Tahoe watersheds. The model can also
forecast the effects of flooding and estimate how
changing climatic conditions may impact the
area's long-term water balance.
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5 10 15 20 25 30
Observed Water Clarity
The water clarity model showed good
agreement between water clarity predicted by
the model (—) and water clarity observed in
Lake Tahoe (®).
The water clarity model provides critical
information for long-term water resource
planning at Lake Tahoe. The model allows
scientists to predict changes in water clarity
based on the lake's capacity to receive and
process sediments and nutrients. Because of
specific design features, this model should be
applicable to other watersheds without
extensive adjustments to accommodate local
conditions.
35
IDENTIFYING STRESSES TO
ECOSYSTEMS
Identifying the factors causing biological
impairment in aquatic ecosystems, and
defending the actions taken based on the
supporting evidence, is an important part of
EPA's decision-making process. ORD, EPA's
Office of Water, Colorado State University, and
several state environmental agencies worked
cooperatively to develop and test an approach
that will meet the needs of water resource
managers at all levels of government.
Completed in December 2000, the Stressor
Identification Guidance Document provides a
method for identifying the factors that cause
damage to an aquatic community. The
document describes a systematic procedure that
water resource managers can follow to identify
manmade or natural causes of an impairment. In
addition to a detailed description of this
procedure, the guidance document also includes
case studies that demonstrate how to apply this
approach.
Sampling a creek upstream from the operation.
Sampling waste effluent from a solids separator
at a concentrated animal feeding operation.
12
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REMEDIATING PCB-CONTAMIIMATED
SEDIMENTS
Polychlorinated biphenyls (PCBs) are toxic
chemicals that persist in the environment for
years and accumulate in human body tissues and
in wildlife through food webs. In the United
States, sediments contaminated with PCBs are a
widespread problem. Subsistence fishermen and
top wildlife predators are often at the greatest
risk of exposure to PCBs due to bioaccumulation
through the food web.
In nature, top predators
have more PCBs per unit of
body weight than the
animals and plants they eat.
Dredging has been used as one of several
methods to remediate PCB-contaminated
sediments. In response to concerns that
dredging PCB-contaminated sediments might
have adverse environmental and public health
consequences, Congress directed the EPA to
evaluate the availability, effectiveness, and costs
of various technologies for cleaning up these
sediments. EPA contracted the National
Academy of Sciences to conduct the study, the
results of which were released in March, 2001
in the report A Risk Management Strategy for
PCB'Contaminated Sediments, The report
concluded that PCBs pose health and ecological
threats and that exposure to these persistent
chemicals may cause chronic illnesses such as
cancer and immunological, developmental,
reproductive, and neurological problems in
humans and wildlife. The report also concluded
that there is no single cleanup technology
suitable for all PCB-contaminated sites,
supporting EPA's site-specific approach toward
remediation. This report supports ongoing ORD
13
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research on persistent, bioaccumulative and
toxic chemicals as well as contaminated
sediment projects conducted by both EPA's
Office of Solid Waste and Emergency Response
and Office of Water. Many of the research needs
listed in the report are being addressed by ORD
in collaboration with the Office of Water and
the Office of Solid Waste and Emergency
Response. This partnership recently led to the
development of a methods compendium for
identifying toxic chemicals at contaminated
sites.
EVALUATING SEDIMENT TOXICITY
Contaminated sediments from a number of
freshwater and marine sites have caused
declines in wildlife populations and changes in
ecological community structure. However,
simply knowing that a sediment is toxic is of
limited value. The specific chemicals causing
toxic effects must be identified before
appropriate action can be taken. The ability to
identify the specific pollutants responsible for
the toxicity of contaminated sediments is
important to the development of water quality
criteria and sediment quality guidelines and to
EPA regulatory programs that deal with dredged
material disposal.
ORD recently completed a manual
addressing this issue, the Sediment Toxicity
Identification and Evaluation Guidance Document.
Using the methods described in this document,
scientists and resource managers can identify
chemicals (or chemical classes) in sediment or
in the water column responsible for an observed
toxicity.
The toxicity identification and evaluation
process is divided into three phases:
characterization, identification, and
confirmation. During characterization, the
general category or type of toxic material
involved (e.g., metals, volatiles, oxidants) is
determined. In the identification phase, the
causative toxic material is isolated from other
chemicals in the sample. During confirmation,
additional data are collected until enough
evidence is accumulated to confirm beyond
reasonable doubt that the suspect toxic material
is in fact causing the toxicity.
LOOKING TO THE FUTURE
Research milestones anticipated in the near
future include
• an evaluation of watershed classification
schemes used to study the response of aquatic
ecosystems to excessive nutrients;
• a report on performance and cost data for
controlling nutrients, sediments, pathogens,
toxic chemicals, and water flow variations in
watersheds with a variety of land uses;
• molecular diagnostic techniques to identify toxic
organisms (e.g., pfiesteria) and determine their
distribution;
• a report comparing dredging, capping, and
monitored natural attenuation as three
alternative waste management solutions for
contaminated sediments; and
• an evaluation of methods to assess the ecological
effects of bioaccumulative organic chemicals in
sediments.
14
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Origins and Fate of PPCPs in the Environment
|11 • Usage by individuals and pets
• Disposal of unused medication to sewage systems
• Underground leakage form sewage systems
12] • Release of treated/untreated hospital wastes to
sewage system
(3] • Release to private septic systems
• Discharge of treated effluent from sewage treatment
plants
• Overflow of untreated sewage due to storms and
system failures
pi] • Use of sewage solids as fertilizer and soil amendment
• Discharge of untreated sewage from homes to surface
waters ("straight-piping")
• Release from domestic animals consuming
medicated feed
|5J • Release to open waters via washing/bathing/swimming
f6J • Discharge of regulated/controlled industrial manufacturing waste
• Disposal/release from illegal drug labs
1^1 • Disposal of domestic refuse and medical wastes to landfills
• Leaching from defective landfills
[8| • Release from fish farming operations using medicated feed
[9] « Release of drugs that also serve as pest-control agents
n£| • Most PPCPs are eventually transported from land to water, where
they are transformed, degraded, or taken up by living organisms.
15
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Air pollution continues to be a
widespread human health and environmental
problem in the United States. EPA's air
quality program aims to ensure that the air in
every American community is safe and
healthy to breathe. In particular, children, the
elderly, and people with respiratory illnesses
need to be protected from health risks of
breathing polluted air.
ORD's air research program provides the
scientific foundation for EPA's air quality
regulations, including the National Ambient
Air Quality Standards (NAAQS) for
particulate matter, ground-level ozone, carbon
monoxide, sulfur dioxide, nitrogen oxides,
and lead. The NAAQS undergo periodic
review and are revised as justified by new
information. ORD also conducts risk
assessment and risk management research for
substances designated as hazardous air
pollutants, or air toxics. ORD's air research
program includes clinical and laboratory.
research, community epidemiologic studies,
and air quality model development and
research. This chapter presents recent ORD
accomplishments in research on particulate
matter, air toxics, and air quality modeling.
PARTICULATE MATTER
ORD's research program on particulate
matter (PM) seeks to answer these key
questions:
• What characteristics of particulate matter (e.g.,
size, chemical composition) cause harm?
* What are the physiologic mechanisms by which
particulate matter causes health probkms?
• What is the role of particulate matter, alone and
in combination with other pollutants, in
producing health problems?
• What groups of people (e.g., asthmatics,
children, elderly) are most sensitive to
particulate matter and what are the critical
levels of exposure for these groups?
• What are the sources of particulate matter and
how can we best estimate the fate of particulate
matter in the atmosphere?
• What are the best strategies to control
particulate matter air pollution?
- -- - . . - .
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17
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Cardiovascular Health Effects
To better understand the health problems
related to paniculate matter, ORD conducted a
series of epidemiologic studies looking at the
relationship between exposure to particulate
matter and physiologic responses in sensitive
populations such as the elderly, children, and
asthmatics. For example, ORD researchers
collaborated with scientists outside EPA to study
the effects of ambient particulate matter on
elderly residents of three retirement centers.
Participants wore portable particulate matter
monitors while multiple pollutants in outdoor
and indoor air were measured. Several
important findings emerged: the relationship
between PM15 and heart rate was consistent
with findings from earlier studies; heart rate
variability decreased at higher concentrations of
PM2J; and respiratory function decreased with
increasing PM2J concentration, which could
have been a reaction to ozone in addition to
particulate matter.
Heart rate variability, which
is controlled by the nervous
system, is the ability of the
heart rate to change in
response to stress.
Decreased heart rate
variability has been
identified as a risk factor for
death from cardiovascular
disease.
To further characterize the effects of
particulate matter exposure on humans, ORD
scientists conducted clinical studies in which
volunteers in a controlled exposure chamber
were exposed to concentrated particles collected
from outdoor air. Healthy young adult
participants (18 to 35 years old) experienced no
symptoms of illness, no reduction in lung
function, and no change in heart rate
variability after a total exposure of two
hours, during which they exercised.
However, when elderly participants (65 to
80 years old) were subjected to the same
study conditions, they immediately
experienced decreased heart rate
variability, which persisted for many hours
after exposure stopped. These findings are
consistent with the studies conducted at
retirement homes and suggest that
A participant being fitted with a portable particulate matter monitor.
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particulate matter exposure
influences nervous system
control of heart rate in older
people.
ORD also collaborated
with academic scientists in
several studies where rodents
were exposed to particulate
matter and other pollutants
collected from outdoor air.
Exposure to particulate matter
was associated with reduced
heart rate and an increased
incidence of abnormal heart rhythms and death,
especially among rodents with compromised
heart or respiratory function. ORD is exploring
the potential mechanisms responsible for these
effects. Additional research is needed to confirm
that the mechanisms in humans are similar to
those in rodents.
Particulate Matter Research Centers
Through ORD's Science to Achieve Results
(STAR) program, EPA established five
Particulate Matter (PM) Research Centers to
investigate the health effects of particulate
Matfef fiesearch Centpl "*
Harvard; University (MA} .^^^:^;.y:-;;4*r::fS
University Sf Rochester (NY) «;?f-;' ;i*;^;i; v
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matter. University scientists are working with
ORD to characterize the relationship between
ambient particulate matter levels and actual
personal exposures, identify the toxic
components of particulate matter and their
associated biological effects, investigate the
amount and distribution of particulate matter
deposited in the respiratory tract, and identify
groups of people that are particularly susceptible
to the adverse effects of particulate matter.
Highlights from the first two years of research
follow.
• Inhalation of particulate. matter at
concentrations only slightly above peak ambient
levels can cause airway inflammation, which
can lead to other physiological responses, such
as thickening of the blood.
• Technologies were developed to collect and
concentrate particulate matter in a controlled
exposure chamber to examine how these
pollutants affect cardiac and pulmonary
function.
19
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• Controlled exposure studies in humans and
animals have shown associations between
ultrafine particle exposures and changes in heart
rate, heart rate variability, abnormal heart
rhythms, and other heart and blood
characteristics.
• Asthmatics may be particularly sensitive to
ultrafine particles because these particles tend to
be deposited in central airways of the respiratory
system.
• In a study of healthy senior citizens, outdoor
PM2J concentrations were significantly
correlated with an individual's personal
exposure to PM2J.
• An epidemiologic study found significant
associations between mortality and exposure to
paniculate matter from traffic and coal'
combustion sources, but not between mortality
and exposure to particulate matter from oil
combustion or soil.
Particulate Matter Supersites
Program
Through EPA's Particulate Matter (PM)
Supersites Program, air quality research projects
are being conducted at eight
locations around the country. The
program has three major objectives:
characterize the chemical and
physical properties of atmospheric
particulate matter, provide data to
support health and exposure studies,
and evaluate new and existing
methods for measuring particulate
matter. Scientists from ORD and
EPA's Office of Air and Radiation are
leading this multidisciplinary
research program. &\r monitoring equipment used in EPA's PM Supersites Program.
Results from the PM
Supersites Program will
significantly improve our
understanding of particulate
matter formation and
accumulation in the
atmosphere throughout the
United States.
Phase I of the Supersites Program was
initiated in 1999. Scientists in Atlanta, Georgia
and Fresno, California evaluated the
performance characteristics of various air quality
monitoring methods and their suitability for use
in state air quality monitoring programs and in
later phases of the Supersites Program. To
exploit the information collected through the
Supersites Program, a data archive was
established with the North American Research
20
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Strategy for Tropospheric Ozone (NARSTO).
The Atlanta data have been submitted to
NARSTO and will be available to the public on
the world wide web. The Atlanta study
produced 35 peer-reviewed papers. A special
subsection in the Journal of Geophysical
Research-Atmospheres will include 22 papers
submitted from the Supersites Program.
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Locations of PM Supersites projects.
Phase II of the Supersites Program consists
of projects in seven locations in the United
States that have different atmospheric and
meteorologic conditions and different sources of
air pollution. The first major Phase II
accomplishment was an intensive monitoring
effort in Houston, TX and surrounding areas.
This was followed by an intensive monitoring
effort in July 2001, when 34 independent studies
and existing national monitoring networks in
the eastern United States were coordinated to
collect the most comprehensive set of air quality
monitoring data ever obtained.
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AIR TOXICS
ORD's air toxics program includes research
on the sources and environmental fate of air
toxics. The research program also evaluates
toxicity, human exposure levels, dose-response
relationships for health problems, and ways to
characterize and manage risks posed by air
toxics. Recent accomplishments in the air
toxics research program are highlighted.
Toxicological Reviews
Risk assessments, formal evaluations of the
likelihood that a substance is a threat to human
health and/or the environment, are used in
developing EPA's regulatory policies.
Conducting accurate risk assessments for air
toxics requires knowledge of the health effects
of toxic air pollutants, data on exposure to air
toxics, and appropriate models to quantify risk
estimates under various exposure scenarios. To
support EPA risk assessments, ORD conducts
toxicological reviews of hazardous air pollutants
and other toxic substances. In 2001, assessments
of three chemicals listed as hazardous air
pollutants under the Clean Air Act-
hexachlorocyclopentadiene, methyl chloride,
and quinoline-were completed. Many other
hazardous air pollutants and chemicals emitted
from motor vehicles are in various phases of
assessment and review.
Concentration-Duration Dynamics
An ORD research team conducted several
studies to determine how exposure
concentration and duration influence the
toxicity of air pollutants. The scientists
identified several fundamental principles
important to predicting the toxic effect of
hazardous air pollutants (see sidebar). This area
of research supports the risk assessment process
by improving the ability to predict health
problems following exposure to specific
pollutants under various exposure conditions.
22
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Emissions from Open Burning
Burning household waste in barrels
has been implicated as a potential major
source of dioxin and dioxin-like
compounds. When EPA received
numerous requests from state and local
agencies for information on emissions
from burn barrels, the Agency conducted
studies to characterize those emissions.
In 1999, scientists from ORD and
EPA's Office of Pesticides, Prevention,
and Toxic Substances (OPPTS) reported
results of a study that characterized bum
barrel emissions as a function of waste
composition, burn conditions, and other
physical properties (e.g., degree of compaction
and moisture content). They found that
emissions varied widely even when burn tests
were performed on wastes of essentially identical
composition. The factors most likely to account
for this variability were total chlorine content,
bulk density of waste, and the combustion
conditions and temperatures. Future studies will
examine other potentially important open
burning scenarios, such as agricultural burning
and construction debris burning.
AIR QUALITY MODELING
Computer models present one approach to
understanding air pollution problems at local,
regional, and national scales. Air quality models
are being used to predict the concentrations of
specific pollutants in a location under various
emission scenarios. Air quality models can also
Firefighters in a controlled bum training class.
be used to allocate the pollutants in a locale to
specific emission sources. With this information,
policy makers can design efficient and effective
air pollution control strategies.
ORD scientists are improving EPA's air
quality modeling methods and systems. The
Models-3/Community Multiscale Air Quality
(CMAQ) system was first released by EPA in
1998, and has been upgraded about once each
year since then. Other ORD research is
providing high-quality data for use in the
Models-3/CMAQ system and other air quality
models.
Models-3/CMAQ
Models-3/CMAQ combines Models-3, a
flexible software framework, and CMAQ, an
urban-to-regional-scale air quality model
designed to assess multiple pollutants. The
modeling system integrates emissions data
23
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processing, weather data modeling, chemistry-
transport models, and analyses of inputs and
outputs. It can simultaneously simulate the
transport and fate of multiple pollutants across
large geographic areas. It was developed as a
multiscale (local, regional, national) and
multipollutant (ozone, fine particulates, acid
and nutrient deposition) model for use by EPA
and state regulatory agencies to support air
pollution control planning. Results of
performance evaluations for four pollutant-
specific applications of the Models-3/CMAQ
system follow.
EPA's Models-3/CMAQ is a
multiscale, multipollutant
modeling system used to
support air quality planning
and atmospheric research.
Performance Evaluation for
Particulate Matter
To facilitate the use of Models-
3/CMAQ, ORD is supporting
collaborative model evaluations
through agreements with several
universities. In one Models-3/
CMAQ evaluation, visibility was
used as a surrogate for fine
particulate matter (PM2J), an
important air quality parameter for
which limited data exist. The evaluation
compared observed visibility at 174 stations in
the eastern half of the United States for a five-
day period with visibility predictions generated
by the model. The evaluation showed a general
agreement between the modeled and observed
values, suggesting the system is a useful tool for
making risk management decisions.
Performance Evaluation for Ozone
The primary task of air quality models for
ozone is to determine how limiting the
emissions of ozone precursors-nitrogen oxides
and volatile organic compounds-will reduce
ground-level ozone concentrations. ORD
scientists evaluated Models-3/CMAQ's
predictive ability for ozone using data from two
field studies. To better challenge the model, the
scientists used data from a two-week period that
included some of the highest and lowest daily
ozone concentrations observed at approximately
560 monitoring sites in the eastern United
States. Based on this initial evaluation, the
-
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0:00 2:00 4:00 6:00
8:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00
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This graph shows that CMAQ (—; predicted the rise and fall in
ozone levels observed at two monitoring stations (* • • and - -)
for one 24-hour period in the Washington, DC area.
24
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Aftef five years of development ^and" J^
testing, jQRD recently Introduced ffie;;;;,;
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model predicts high-ozone days quite well, but
performs less satisfactorily on low-ozone days. It
is worth noting that, while addressing multiple
pollutants simultaneously, the model's
performance is consistent with that of other
models that simulate only ozone levels.
Performance Evaluation for Atrazine
ORD scientists expanded CMAQ to
simulate how meteorologic factors interact to
control the fate of semivolatile organic
compounds, such as atrazine, dioxin, and
dioxin-like compounds, over regional and local
scales. Emissions of atrazine, a common
agricultural herbicide, were modeled for a four-
month period over the eastern United States.
Comparing model results to observations
showed that the model underpredicts atrazine
deposited via precipitation while it overpredicts
atrazine air concentrations. These findings
imply that the model insufficiently accounts for
the removal of airborne atrazine by rainfall and
other forms of precipitation. ORD scientists are
revising the model, with the goal of producing a
CMAQ/atrazine model for public release in the
near future.
25
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Performance Evaluation for Mercury
ORD scientists developed the first version
of a mercury module for CMAQ (CMAQ-Hg)
in early 2000. Following a model comparison
exercise sponsored by the European Monitoring
and Evaluation Programme, the module was
upgraded to better simulate the fate and
transport of this toxic chemical. Still,
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uncertainties exist regarding mercury chemistry
in the atmosphere. By comparing model
performance with measurements of mercury
deposited at 11 sites across the eastern United
States, ORD hopes to better understand the
chemical processes that determine the fate of
mercury in the atmosphere, and continue to
refine the model.
Biogenic Emissions Inventory
System
Biogenic emissions are compounds released
from plants and other living organisms. In the
presence of nitrogen oxides from manmade
sources, biogenic emissions contribute to
ground-level ozone formation. Therefore, ,
accurate estimates of biogenic emissions are
critical for assessing the regional-scale
atmospheric processes that produce ground-level
ozone and for formulating cost-effective
pollution-control strategies.
Emitted mainly from forests,
biogenic emissions are the
largest single source of
atmospheric volatile
organic compounds in the
United States.
The Biogenic Emissions Inventory System
(BEIS) is a computer program that estimates
emissions of volatile organic compounds from
vegetation in large geographic areas. ORD
scientists recently released a new version of the
26
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program, BEIS3, which can produce emission
estimates for use with EPA's Models-3/CMAQ
system. Using model simulations and
measurements taken in the field, ORD scientists
confirmed high emissions of isoprene (one
compound emitted from forests) from the
Ozarks and the southeastern United States. This
information will help determine how emissions
of manmade nitrogen oxides should be regulated
to reduce the formation of ground-level ozone.
In addition to the Models-3/CMAQ system,
emissions estimates generated by BEIS3 can be
used in other air quality simulation models
including EPA's Regional Acid Deposition
Model.
ORD scientists also completed the Biogenic
Emissions Landuse Database, which combines
data on major vegetation species and land cover
types in North America with emission data for
35 compounds. Both BEIS3 and the Biogenic
Emissions Landuse Database provide biogenic
emissions data for use in air quality modeling
simulations.
Amount of biogenic emissions in regions of the
United States characterized by different types of
vegetation. Quantities are expressed as micrograms
of carbon emitted per square meter per hour.
LOOKING TO THE FUTURE
Anticipated achievements in ORD's air
quality research program include
• a report on personal exposure to, and indoor air
concentrations of, paniculate matter and
gaseous pollutants for potentially sensitive
individuals;
• a report on the cardiovascular effects of ambient
particulate matter in healthy and susceptible
humans and animals;
• predictive models for selected toxic compounds
that auantify the relationships among exposure,
dose, and the body's response;
• dose-response assessments for priority air toxics
including benzene, 1,3'butadiene, cadmium,
chloroform, and chloromethane; and
• characterization of fine particulate matter
samples from priority sources such as pulp and -
paper mill operations and open burning.
27
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The U.S. Global Change Research Program
is an integrated, multiagency effort that helps
the nation and world understand, assess, predict,
and respond to global change. Eleven agencies
within the federal government, including EPA's
Global Change Research Program within ORD,
participate in the U.S. Global Change Research
Program.
EPA's Program is assessment-oriented and
focuses on the potential consequences of
climate variability and climate change on
human health, ecosystems, and social well-being
in the United States. In addition, the Program
investigates the effects of multiple stresses, the
human dimensions of global change (as human
REGIONAL-SCALE CONSEQUENCES
As part of its commitment to the U.S.
Program, EPA's Global Change Research
Program is sponsoring assessments in the Mid-
Atlantic, Great Lakes, and Gulf Coast areas.
The first peer-reviewed assessment reports were
published in 2001 as part of the U.S. Program's
first National Assessment. These ongoing
assessments are conducted through public-
private partnerships that engage researchers
from the academic community, resource and
environmental managers, and other affected
stakeholders. The focus of the assessments on
specific geographic areas reflects the fact that
the effects of climate change will differ across
activities influence and respond to global
change), and adaptation options that can build
resilience to change. The goals of EPA's Global
Change Research Program are consistent with
three key elements of the U.S. Program's
Strategic Vision for the next decade: develop
regional-scale predictions of the interactions
among natural and human-induced changes;
determine the vulnerability of natural resources
and evaluate options for enhancing resilience;
and provide useful knowledge for decision
making by governments, communities, and the
private sector.
the nation and that people will experience these
impacts where they live.
The Mid-Atlantic assessment concluded
that climate change may have a positive impact
on agricultural production of soybeans, and
possibly corn and tree fruits, but a negative
impact on tobacco production. Increased
temperatures will make urban heat stress more
likely. Forests might grow a little faster, but
extreme weather events such as tornados and
floods could disrupt the pattern of revenues
from forestry operations. Rising sea levels will
almost certainly occur, with the potential for
29
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substantial damage to coastal structures,
wetlands and estuaries, and to water supplies
because of salt water intrusion. What are now
considered one-hundred-year floods will occur
every 25 to 30 years. Such storms can disrupt
human communities, transportation, waste
treatment, emergency services, and wildlife
ORD scientist measuring light-harvesting
efficiency of salt-marsh plants.
habitats. Resource managers are working to
identify and design effective, site-specific
adaptive measures in anticipation of future sea
level rise.
The Great Lakes assessment
concluded that, despite a
projected increase in
precipitation, increased
evaporation due to higher summer
air temperatures will lead to lower
water levels in the Great Lakes.
Lower lake levels will reduce
hydroelectric power generation
downstream, with projected
reductions up to 15% by 2050. An
increase in demand for water
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80
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20
1950
across the region at the same time net flow
decreases is of particular concern. Lower lake
levels are also a concern for the commercial
shipping industry because locks and channels
may become too shallow for big ships to pass
through. As a result of the assessment, this
industry is considering options such as
lengthening the shipping season, redesigning
ships to have a shallower draft, redesigning locks
and channels to accommodate the new ships,
and dredging shallow channels.
The Gulf Coast Regional Assessment
concluded that increasing temperatures and
carbon dioxide may increase production of
certain agricultural crops, but this benefit may
be offset by problems with runoff of agricultural
chemicals to coastal wetlands and seawater
contamination of agricultural soil. Rising sea
levels are expected to lead to salt water
intruding inland where it will mix with surface
and ground waters. Also, changing precipitation
1960
1970
1980
1990
2000
Reductions in com yields often correspond to extreme climate
events such as droughts and floods.
30
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patterns in the central United States will alter
the timing and delivery of fresh water to
estuaries along the Gulf Coast. Changing
salinity patterns will threaten the stability of
freshwater coastal ecosystems and shellfish
stocks, especially oysters and shrimp.
HEALTH CONSEQUENCES
EPA's Global Change Research Program is
also sponsoring ongoing Health Sector
Assessments. These assessments examine the
potential impacts of climate variability and
change on human health. The first Health
Sector Assessment, conducted as part of the
U.S. Program's first National Assessment, was
published in May 2001. It identified five
categories of health outcomes that are most
likely to be affected by climate change because
they are associated with weather and/or climate
variables: temperature-related morbidity and
mortality; health effects of extreme weather
events (e.g., storms, tornadoes, hurricanes,
floods, and blizzards); air pollution-related
health effects; water- and food-borne diseases;
and insect- and rodent-borne diseases. The
report also identified groups at risk, key research
areas, and public health measures that, if
properly addressed, could improve the public's
resilience to risks associated with current
climate variability and future climate change.
Uncertainties about many future variables,
including population, economic conditions,
other possible health or societal priorities (e.g.,
an unanticipated epidemic or war), as well as
the complexities of human behavior, are
acknowledged and addressed in the analysis.
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Average Summer Mortality Rates Attributed to Hot
Weather Episodes. Deaths due to summer heat are
projected to increase in U.S. cities. Because heat-
related illness and death appear to be related to
temperatures much hotter than those to which the
population is accustomed, cities that only infrequently
experience extreme heat appear to be at greatest risk.
Note: Estimates for 2020 and 2050 are based on the
Max Planck GCM model results (IPCC 1994).
31
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The Health Sector Assessment made great
progress toward understanding the potential
consequences of climate variability and change
for human health in the United States and
provided timely and useful information for
public health officials and other decision
makers. The report concluded that the United
States has a solid public health infrastructure.
However, we are frequently reminded that
human health is inextricably bound to weather
and the many complex natural systems it affects.
Weather-related deaths, such as fatalities in heat
waves and floods, and illnesses such as water-
borne and vector-borne diseases continue to
occur. The future vulnerability of the U.S.
population to the health impacts of climate
change depends on our capacity to adapt to
potential adverse changes. Approaches to
reduce vulnerability include building codes and
zoning to prevent storm or flood damage, severe
weather warning systems, improved disease
surveillance and prevention programs, improved
sanitation systems, better education of health
professionals and the public, and additional
research addressing key knowledge gaps in
climate-health relationships.
PUBLIC ACCESS TO INFORMATION
The U.S. Global Change Research Program
is committed to providing timely and useful
information to decision makers. In November
2000, the program successfully established a web
site through which scientists, resource managers,
policy analysts, and the public can access
information about the Program. The goal is to ,
make the products from EPA researchers,
grantees, and other collaborators-including
data, results of EPA-sponsored assessments,
project descriptions and updates, workshop
announcements and proceedings, and analytic
tools—readily available to interested parties.
Dengue fever along the U.S.-Mexico
border. A mosquito-borne viral
disease, dengue fever was once
common in Texas, where there were
an estimated 500,000 cases in 1922.
The mosquito that transmits the virus
remains abundant. The striking
contrast in the incidence of dengue in
Texas versus three Mexican states
that border Texas (64 versus 62,514
reported cases from 1980-1999)
provides a graphic illustration of the
importance of factors such as use of
air conditioning and window screens
in interrupting the transmission of
vector-borne diseases. This is one
example of how relatively simple
adaptive measures can reduce the
health impact of a climate-related
vector-borne disease.
32
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LOOKING TO THE FUTURE
Several major research and assessment
products are expected during the next two years,
including
• an assessment of the potential impacts of sea
level rise on water quality and drinking water
systems along the Gulf and Atlantic Coasts;
• an interim assessment of the potential effects of
global change on urban air quality;
an assessment of the potential consequences of
global change on selected watersheds; and
an interactive decision-support tool,
implemented through the Global Change
Research web site, that supports the decision
and analytic needs of water resource managers,
coastal zone managers, and agricultural
planners.
33
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Research to support ecosystem assessment
and restoration is one of EPA's highest priorities
At ORD, the objective of ecosystem research is
to provide information that truly reflects the
scale of the problem, need for action, causes of
harm, and success of mitigation and restoration
efforts; computer models that integrate the
impact of multiple factors causing ecological
degradation and are appropriate to the scale of
the problem; risk assessment techniques that
accurately quantify risks to ecosystems; and
restoration and protection strategies that are
cost-effective. This chapter describes recent
ORD accomplishments in ecosystem research.
MONITORING COASTAL CONDITION
The National Coastal Condition Report
was produced through EPA's Environmental
Monitoring and Assessment Program (EMAP).
Released in 2001, the report exemplifies
cooperation between EPA and State, local,
tribal, and federal natural resource trustees. The
National Coastal Condition Report is a major
demonstration of the type of information
generated by EMAP.
Most of the data used to develop the
Report were collected in estuaries—areas
where rivers and streams flow into the ocean.
Due to the influx of nutrients from the land
Questions tftaljbriye'
Ecosystem Research
[s the,current,ecosystem condition,
has ecosystem condition changed
^
appear to have^beeTTresponsible for Harm
jteterioration?
L How dojbiological chemical, and physical
Sprocesses affect the condition of
^^ _
can^we mosf accurately diag'nosis^"
"" problems facing^cosystems and forecast
i future effects of stresses to ecosystems?
Wliat relative risks do stressors (alone
nd in combination) pose to ecosystems
'"' ~
_,„._,-.. „„_..j most effe£tive^reduce jsKs
:z^ to^protecTecosysterns^afid restore them _
^Qjlce they have become degTacted9
and the mixing action of tides and currents,
estuaries and their associated wetlands are
among the world's most diverse and productive
ecosystems. Because estuaries are important
commercially and environmentally, programs
monitoring estuarine conditions have been in
place since at least 1990.
Seven primary indicators of aquatic
ecosystem health were used for the National
Coastal Condition Report: water clarity,
dissolved oxygen, coastal wetland loss, eutrophic
condition (presence of excess nutrients),
sediment contamination, benthic condition
(status of bottom-dwelling ecological
35
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Environmental monitoring,
which enables scientists to
observe trends in changing
conditions, is the
cornerstone of ecosystem
assessment.
communities), and fish tissue contamination. In
each coastal area studied, the condition of each
indicator was rated as good (5), fair (3), or poor
(1). Available information enabled full
assessments of the northeastern, southeastern,
and Gulf of Mexico estuaries. Partial
assessments were made of West Coast estuaries
and the Great Lakes. The national score was
derived as the average of regional scores,
weighted by the amount of estuarine area in
each coastal area studied.
The overall condition of the Nation's ,
estuaries was fair to poor. Nearly half (44%) of
the estuaries were impaired in their ability to
support healthy aquatic life and/or full human
use, such as fishing and swimming. The lowest-
scoring ecosystem indicators were coastal
wetland loss, eutrophic condition, and benthic
condition, while the highest-scoring indicators
were water clarity and dissolved oxygen
concentration. This report provides an
important baseline for evaluating the progress of
coastal preservation and restoration projects.
PREDICTING NUTRIENT AND
SEDIMENT LOADINGS
Two of the most important stressors to
aquatic ecosystems are excessive nutrients and
sediment, which upset the balance of microbial,
plant, and animal life. Scientists from ORD and
other federal agencies are working together to
Ecological Health
Water Clarity
Dissolved Oxygen
Coastal Wetlands
Eutrophic Condition
Sediment
36
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develop computer models that
predict nutrient and sediment
loadings to streams in the
Mid-Atlantic area of the country.
These models should be broadly
applicable across the Mid-Atlantic
area because they are based on data
from a large number of sites (148)
representing several settings with
diverse biological and physical
features.
The researchers developed
landscape metrics (see sidebar) and
related them to in-stream
measurements of nitrogen,
phosphorus, and sediment. Nitrogen,
phosphorus, and sediment levels in the streams of
the Chesapeake Bay Basin, which contains
150,000 stream miles in the Mid-Atlantic area,
were highly correlated with the amount of
agriculture, forest adjacent to streams, nitrate from
precipitation, and roads in the watershed. Because
of the strong correlation between certain
^T:
indscape metrics jre^me^iMHe1eatures7sIiS
rEyTSesTFoT
landscape metrics and nutrient and sediment loads
found in this study, it will be possible to estimate
loading to streams across the Mid-Atlantic area
using extensive landscape data collated by EPA.
Also, it should be possible to evaluate the
likelihood of exceeding nutrient and sediment
thresholds for many streams across the region.
pfas percentage Wan areaTcoveredTByioTesTrFoF """"'^sJcenTloHreaWiHge'r
S?4his study, landscape metrics were i 1
^database for the Mid-Atlantic area j|^]ncl5|^ frTprocipTtatroiir
fe^H.S"BB--SB!" •535- — .„. „ ,.!2j*.ss_ rrL~i!7Tt±jL 3stT"?"* i=^s?saH^s''sH?^»^K^ffl^~^i3ai™l*^*!™fe;S* __ _ _
™a"a. i^ 1_ Ht &&-.=#£_" $^3&!t$&!ii£3!8^-iia^&-rK^uHxiffB^^ •<«««, -~i -
jata on jand coverj, regional topograghy, soil type, _ Road dertsj^average length of roaaVper area of
Jre.amTietworks', road netwrafkCsuTdTuiman_""_ watersfiiiT" "~~~ ~*"
apulation density. The •
length
^metricsare examples oTthose usedinthe_
" ' "" "~"' ""
SBjpartan agriculture percent of watersneawlri
" having roads within 3D meters of the stream 1 ^__
~
land adjacent to stream edge.
potermaTfor soTTtosses greater than 2000 pounds
.r
37
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Working under ORD's STAR grant program, a scientist at
the Reef Indicators Lab of the University of South Florida
has developed guidelines for using foraminifera, tiny
marine organisms, as ecological indicators of vitality for
coral reefs. The organisms with uniform pinwheel stripes
are healthy; the ones with irregular white blotches are
bleached, evidence of damage. Foraminifera range in
size from 0.1 to 3 mm in diameter.
STUDYING MERCURY CYCLING
Mercury is a naturally occurring element
that cycles between the atmosphere, land, and
water. Emissions from human activities, such as
burning coal for electricity and incineration of
municipal waste, are the largest contributors of
biologically available mercury to the
environment.
ORE) scientists developed an instrument to
detect different forms of mercury in the
atmosphere. Using an aircraft equipped with
this apparatus, the researchers learned that
elemental mercury can be transformed to
reactive gaseous mercury in the middle and
upper layers of the troposphere (the atmospheric
layer closest to the ground). Reactive gaseous
mercury is more readily removed from the
atmosphere and deposited on land and water
than elemental mercury. Prior to this
research, elemental mercury—the
predominant form in the atmosphere—
was believed to be largely inert and
hence typically transported long
distances. Apparently, mercury from both
nearby and distant sources contributes to
both local and regional deposition. Since the
initial flights, which occurred off the coast of
Florida and over the Gulf of Mexico, ORD
scientists have corroborated the original
findings using similar instruments deployed at a
land-based, high-altitude research station in
Hawaii.
The specific mechanisms by which
elemental mercury is transformed to reactive
gaseous mercury are yet to be determined.
However, ORD scientists studying atmospheric
mercury in the Arctic and Antarctic found
evidence that bromine-containing and chlorine-
containing compounds can be formed in the
atmosphere and, in turn, react with elemental
mercury to produce reactive gaseous mercury.
•
38
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These findings imply that
atmospheric mercury is
much more dynamic than
we had thought and that
controlling mercury
emissions can result in
meaningful decreases in the
amount of mercury being
deposited on land and water.
Two teams of scientists working under
ORD's Science to Achieve Results (STAR)
grant program are studying mercury cycling in
natural waters. One team is using a combination
of field and laboratory experiments to
investigate the major chemical and biological
mechanisms responsible for the transformations
between various forms of mercury. During the
first year of research, the scientists discovered
that the oxidation of elemental mercury in
surface waters in the presence of sunlight, a
process that was thought to be insignificant, is a
very important aspect of mercury cycling and
transformation. Therefore, daily and seasonal
variations in sunlight should be considered when
calculating mercury budgets in aquatic systems
and when developing sampling protocols.
The second team of STAR grant recipients
is conducting comprehensive field and
laboratory studies of mercury cycling in the
coastal and estuarine waters of Long Island
Sound and its
river-seawater
mixing zones.
These researchers
are investigating
the chemical and
biological
reactions and
Sample water is delivered to
the glass bubbler portion of the
AGEMS system shown here.
A measured volume of sample
water is purged with nitrogen
gas and the elemental mercury
from the water sample is
delivered to the analytical
and bioavailability portion of the system.
in waters and
processes
controlling
mercury cycling
sediments. The scientists designed an
Automated aqueous Gaseous Elemental
Mercury sampling and analysis System
(AGEMS) for ship-board use that allows direct
analysis of elemental mercury in surface waters.
Sampling excursions have identified spatial and
seasonal patterns in the distribution of
elemental mercury in Long Island Sound.
LOOKING TO THE FUTURE
Upcoming accomplishments include
• a report assessing the condition, vulnerability,
and restoration potential of streams and their
watersheds in the Mid'Atlantic area,
• a report on trends in acid deposition and the
acidity of lakes and streams, to assess progress
toward reducing the impacts of acid rain, and
• development and evaluation of new,
cost-effective indicators to evaluate the
ecological condition of aquatic and terrestrial
environments.
39
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lip
:%,; iJi
i&'-r'4j „;,
-------
EPA uses risk assessments to identify and
characterize potential threats to human health
associated with exposure to pollutants. There
are many uncertainties in the risk assessment
process due to limitations in available data on
pollutant sources and exposures. In addition, we
are limited in our current understanding of the
physical, chemical, and biological processes that
relate human exposure, dose, and response.
ORD supports EPA's mission to protect human
health by conducting research to improve
human health risk assessment and risk
management.
and Cosmetic Act; and the Toxic Substances
Control Act. This chapter highlights recent
ORD accomplishments in research to protect
human health.
DIOXIN
Dioxin and related compounds are toxic
chemicals formed as byproducts of combustion.
They are widely distributed throughout the
environment in low concentrations, persist in
the environment, and accumulate in the body.
Numerous animal research studies indicate that
dioxin and related compounds can cause several
ORD conducts human health risk
assessment research to develop risk assessment
methods to more accurately assess and
characterize hazards from exposure to pollutants.
This includes research on risks to the general
population and to vulnerable groups such as
children and communities that rely heavily on
subsistence fishing, hunting, or farming.
ORD also spearheads research under the
Food Quality Protection Act to ensure that
pesticide residues on food do not pose a health
hazard. Other ORD research provides the
scientific foundation for regulatory decisions
made under the Federal Insecticide, Fungicide
and Rodenticide Act; the Federal Food, Drug,
types of cancer as well as reproductive failure
and developmental problems. A growing body
of evidence suggests that humans are similarly
affected.
Dioxin Reassessment
Since 1991, scientists from EPA, other
federal agencies, and the general scientific
community have conducted a comprehensive
reassessment of the human health problems
caused by dioxin and dioxin-like compounds. In
2001, the reassessment passed its final peer
review.
During the last few years, ORD scientists
have made significant contributions to our
41
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understanding of dioxin toxicity, mechanisms of
action, and the sources of dioxin and dioxin-like
compounds in the environment. ORD
researchers developed methods for measuring
dioxin dose and for relating those measurements
to exposure; studied the assumptions and
uncertainties underlying the current method for
determining total dose when the situation
involves simultaneous exposure to multiple
individual dioxin-like compounds; applied
innovative computer modeling techniques to
identify the contributions of various dioxin
sources to human exposure; and developed a
user-friendly, widely accessible compilation of
dioxin sources in the United States. This
information was incorporated into the
reassessment to provide a more accurate
scientific understanding of the nature and
extent of dioxin exposure and risk. EPA will use
the revised dioxin risk assessment to develop a
comprehensive risk management strategy. EPA
will review the existing dioxin risk management
efforts and, where appropriate, modify, expand,
or redirect them to ensure that they are
responsive to the scientific findings of the ,
reassessment.
Dioxin and Reproductive Health
Historically, studies examining the potential
association between dioxin exposure (from
herbicides) in Vietnam veterans and neural tube
defects (e.g., spina bifida) in their children have
yielded conflicting results. Often, these studies
had relatively few participants and might have
been subject to sampling bias. Academic
scientists funded by ORD are conducting a
study that overcomes these shortcomings and
examines the possibility that an interaction
between dioxin exposure and a specific genetic
anomaly may increase the risk of neural tube
defects. To avoid sampling bias, the scientists
contacted all Vietnam veterans for whom they
could obtain a valid address. Those who
parented a child with a neural tube defect and
who agreed to participate in the study were
asked to complete a questionnaire and provide a
blood sample that was analyzed for dioxin and
the genetic anomaly being investigated. A
corresponding group of veterans whose children
did not have neural tube defects will act as a
control group for the study. By the end of 2001,
136 cases of veterans with affected children'had
been identified, from which 75 will be selected
for participation in the study.
42
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First EPA Biotechnology Patent
In 2001, an ORD scientist became the first
EPA researcher to obtain a biotechnology patent
on behalf of EPA. The patent is on the sperm
protein SP22, the DNA nucleotide and amino
acid sequence of SP22, and all recombinant
fragments thereof. A second patent, covering the
use of SP22 in fertility diagnostics and other
reproductive technologies including
contraception, artificial insemination, and in vitro
fertilization, is pending.
The ORD scientist discovered SP22 while
conducting rodent studies to identify molecular
factors associated with infertility. When rodents
were exposed to multiple chemicals known to
cause infertility, levels of one sperm protein were
consistently diminished. Furthermore, the
amount of this protein was highly correlated with
fertility. Because this sperm protein was 22
kilodaltons in size, it was named SP22. The data
indicate that SP22 plays a critical role in the
initial interaction of the sperm and egg during
fertilization. Subsequent studies have used
antibodies to SP22 to identify the location of
SP22 on sperm from several species, including
humans.
In this photomicrograph, sperm are attached to the
zona pellucida surrounding the egg. Only one will
penetrate the zona pellucida and fertilize the egg.
Preliminary data obtained from men with
infertility of unknown cause show reduced SP22
levels, confirming that SP22 levels may be used
as an indicator of male reproductive capability.
An epidemiologic study is underway to
determine if environmental exposure to varying
levels of chemical byproducts formed during
drinking water disinfection affect SP22 levels in
human sperm.
100
5,000
10,000 15,000
SP22 (I.O.D.)
20,000
The relationship
between fertility
and SP22 levels.
SP22 is measured
in integrated optical
density units
(I.O.D.).
-------
Dermal absorption
Information on the absorption of chemicals
through the skin is used to make decisions
regarding pesticide registration. Many years ago,
EPA scientists developed an in vivo rat protocol
for evaluating the absorption of chemicals
through the skin. Since that time, pesticide
manufacturers have conducted over 300 dermal
absorption studies using this protocol, which is
the only validated method currently available.
Scientists from ORD and EPA's Office of
Pesticide Programs recently compiled 329 of
these studies in a database. ORD researchers
used this database to investigate how specific
physical and chemical characteristics govern
dermal absorption and to evaluate alternative
methods for measuring dermal absorption. The
scientists identified the key data elements
needed to validate dermal absorption methods.
They also evaluated previous validation studies
for in vitro dermal absorption methods and found
that these studies frequently lacked adequate
concentration ranges and exposure times to
compare the in vitro methods with the in vivo
methods. Therefore, they concluded
that current in vitro dermal absorption
protocols have not been adequately
validated. The dermal absorption
database may be used to develop
simulation models that predict the
behavior of chemicals in the
environment and their effects on
people who work with pesticides or
who come in contact with chemically
contaminated soils.
In support of the Food Quality
Protection Act, scientists at ORD and
EPA's Office of Pesticide Programs are
collaborating with academic scientists
to develop methods, data, and models for
evaluating children's cumulative exposure to
pesticides. Results of an initial assessment
indicate that exposure via skin contact and
indirect ingestion may be high. Because data
available to assess dermal and indirect ingestion
exposure are limited, a draft protocol for
measuring children's exposure to pesticides has
been developed by ORD researchers. This
protocol, which is currently being tested,
provides approaches and methods to collect
44
-------
exposure measurement data during field studies
and to identify factors associated with exposure
that are needed to improve assessments of
dermal and indirect ingestion exposures.
Children's Exposure
ORD is collaborating with EPA's Office of
Pesticide Programs and the National Center for
Health Statistics to study pesticide exposure in
children and adults through the current
National Health and Nutrition Examination
Survey (NHANES), which began in 1999.
The study addresses two major questions:
• What is the baseline national exposure to
common pesticides in the United States?
• Do pesticide exposure levels vary according to
age?
The study includes a screen for
organophosphate pesticides in
the urine and measurement of
urinary concentrations of 32
nonpersistent pesticides or
pesticide metabolites.
Approximately 2,500 samples
will be analyzed, half from
children age 6 to 11 years and
half from persons between 12
and 59 years of age. Data
collection was completed in
2001 and the National Center
for Health Statistics plans to
release the analyzed data on
levels of pesticides by late 2002.
Repeated Exposure to Chlorpyrifos
While the health problems associated with
short-term exposure to high doses of pesticides
have been studied fairly well, the adverse
consequences of chronic exposure to lower
pesticide levels has not been thoroughly
investigated. ORD researchers and academic
collaborators are studying long-term exposure of
rats to the organophosphorous pesticide
chlorpyrifos. The primary purpose of the study is
to determine what, if any, health problems may
be caused by chronic exposure and what pattern
of exposure is most harmful. The scientists also
hope to learn if chlorpyrifos must enter the
brain and spinal cord to cause harm or if
45
-------
chlorpyrifos in the body and peripheral nerves,
but not in the brain and spinal cord, can cause
health problems. In 2001, the exposure phase of
the study was completed and end-of-exposure
assessments were conducted. The results will be
reported at scientific meetings and in peer-
reviewed journals and EPA reports.
The use of chlorpyrifos by homeowners and
in schools, parks, and other settings where
children may be exposed was canceled effective
December 31, 2001. However, the findings from
the chlorpyrifos research may be important for
assessing residential exposure to other
pesticides.
Atrazine Mode of Action
Atrazine is a widely used herbicide that has
been linked to mammary tumors in one strain of
female laboratory rat. In the United States each
year, an estimated 68 to 72 million pounds of
atrazine is used to control annual grasses and
broadleaf weeds, primarily in the cultivation of
food crops and evergreen trees. In the heavily
farmed Midwest, many drinking water sources,
including groundwater, contain atrazine and
similar herbicides. The fact that atrazine
induced mammary tumors in laboratory animals
raised concerns about potential health problems
in humans.
Evidence from earlier studies pointed
toward a hormonal mechanism of causing
Relationship between DNA damage and dose of atrazine.
46
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cancer that is unique to the one strain of rat.
However, many compounds that cause cancer
damage the DNA of cells, a phenomenon called
genotoxicity. Previous in vitro and in vivo studies
of atrazine's potential for genotoxicity produced
conflicting results, which prompted ORD
scientists to conduct experiments to determine
conclusively if atrazine is genotoxic. They found
that atrazine caused only slight DNA damage at
very high doses.
Pesticide Risk Modeling System
ORD released a new version of the Exposure
Analysis Modeling System (EXAMS) in
September of 2000. EXAMS is a site-based,
interactive computer program that constructs
simulation models of aquatic ecosystems. It
rapidly evaluates the fate, transport, and
concentrations of synthetic organic chemicals
such as pesticides, industrial materials, and
substances leached from waste disposal sites.
EXAMS offers a scientifically sound approach to
characterizing the element of risk (directly to
aquatic resources, and indirectly to humans
through fish and shellfish consumption) posed
by pesticide contamination of freshwater,
estuarine, and marine ecosystems.
In 2001, ORD scientists
designed and published
methods to measure how
reliably simulation models
predict exposure to
pollutants.
REGIONAL TRANSPORT
\/\ \ A v\x\
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DRAWAL
FROM
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SEEPAGE AGROUND-WATER
DISCHARGE
RECHARGE TO STREAMS
FROM
STREAMS
SEEPAGE
ENTRY
^ JHROUGH
-™K WELLS
Diagram of
major factors
to include
when modeling
pesticide risk.
47
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In related work, ORD researchers are
developing a climatological database, including
30 years of data from 239 U.S. weather stations,
to provide simulation models with a single,
unified source of high-quality data covering a
full range of weather factors that affect pesticide
exposure.
3MRA MODELING SYSTEM
In 1999, ORD and EPA's Office of Solid
Waste distributed Version 1.0 of a new
site-based risk assessment modeling system.
The 3MRA system is a state-of-the-science
environmental modeling technology that can
simulate
• Multimedia (air, water, soil, sediments),
• Multipathway (e.g., foodingestion, water
ingestion, soil ingestion, air inhalation),
• M.ultireceptor (e.g., resident, farmer, gardener,
fisherman, ecological populations) •
exposure scenarios for
• Risk (human cancer risk and noncancer effects,
ecological population and community effects)
• Assessment (strategy used to provide
information for regulatory decisions).
Methylmercury Reference Dose
The oral reference dose (RfD) is an estimate of an oral daily dose that humans^ (including
sensitive people) could ingest without an appreciable risk of noncancer, nonmutagenic* health
problems during a lifetime. This estimate has some uncertainty spanning perhaps an order of
magnitude. In general, doses less than the RfD are not
likely to be associated with health problems, and are ;;»;;
. ; - - ;v FUSE'S
therefore less likely to be of regulatory concern. However, i|g
it is not appropriate to conclude that all closes below the ; ^ v-r*
RfD are risk-free or that all doses in excess of the RfD will ; : v
: - : ••':'-; ^
cause health problems. ; j '" _ %
In 2001, ORD scientists completed the work - ., •;;, ;? fe ,lfp » ffW]v?«*;.?'^ -
necessary to assign aniRfD for methylmercury, which ->., • ; ; ;
causes developmental neuropsychological disorders to ;
children exposed in utero. The primary sburce of ingested methylmercury is contarpinated fish.
The methylmercury RfD workgroup evaluated data from epidemiologic, human clinical, and
laboratory toxicologic studies and other scientific reports to establish an RfD for chronic oral
exposure of 0.0001 mg/kg of body weight per day. Also, the workgroup identified several areas
that require additional research and/or afialysis: cardiovascular effects, persistent and delayed
neurotoxicity, and reproductive effects. i
* Because of the cellular mechanisms that lead to cancer development and that cause
genetic mutations, theoretically, there', is no threshold below which exposure to a
carcinogen ormutagen is considered:to be without risk. However, RfDscan be derived
for the noncarcinogenic and/or nonmutagenic effects of substances that also cause
cancer or genetic mutations.
48
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3MRA was initially
developed to support the
Hazardous Waste
Identification Rule, which is
an important regulation that
defines when wastes are
hazardous and subject to
regulation under the under
the Resource Conservation
and Recovery Act. A major
application of 3MRA is to
pinpoint the level at which a
waste is classified as
hazardous for management
and disposal purposes. 3MRA
is a flexible risk assessment
tool that can be applied to
other waste programs and
used to answer increasingly complex risk
questions. In fact, the potential applications
are so broad that EPA signed a Memorandum
of Understanding with the Nuclear
Regulatory Commission, Department of
Energy, Department of Defense, U.S.
Geological Survey, and U.S. Department of
Agriculture, creating a common infrastructure
for risk assessment technology development.
These agencies have similar technology needs
and this Memorandum will prevent
unnecessary duplication of effort and promote
development of a single technology that can
be used by all these agencies.
LOOKING TO THE FUTURE
Anticipated accomplishments in human health
research include
• a summary of the methods available for
assessing aggregate exposure to multiple
pesticides and the effects of such exposures,
* innovative technology for data collection and
loW'Cost exposure measurement methods to be
used for studying children's exposure to
pesticides,
« publications on the susceptibility of asthmatic
children to combustion-related pollutants in
seven communities,
• identification of common mechanisms by which
pollutants cause different health problems, and.
• a state-of'the'sdence report on how aging
relates to risk assessment.
49
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-------
EPA recognizes that pollution prevention,
rather than remediation, is the preferred
solution to environmental problems. EPA's
approach to pollution prevention includes
fostering innovative design and production
techniques to minimize or eliminate industrial
waste, creating fundamental changes in the
production and delivery systems that move
goods and services to the American consumer,
and developing sustainable approaches for using
our natural resources.
At ORD, pollution prevention and new
technologies research is targeted at the sources
that pose the greatest risks to human health and
the environment. This research informs
regulatory officials, industry, and consumers
about pollution prevention opportunities and
presents verified, commercial-ready
technologies and methods for use in both the
public and private sectors.
ORD encourages the
development of promising
pollution prevention
techniques and other
technologies.
NONPOLLUTING METAL SURFACE
FINISHING
Metal surface finishing is a major industry
that uses large quantities of hazardous chemicals
and produces significant amounts of hazardous
waste. Developing a metal surface finishing
process that reduces the amount of chemicals
used and the amount of waste generated, while
maintaining product output, would benefit the
metal finishing industry and the environment.
Under laboratory and field conditions, ORD
scientists conducted an assessment of Picklex®, a
nontoxic proprietary product, as an alternative
to conventional metal surface pretreatments.
The results of both laboratory tests and a field
demonstration showed that Picklex® can
provide effective and efficient metal surface
preparation for many metal finishing operations.
The Picklex® process requires fewer steps, avoids
the use of some hazardous chemicals, and
generates no hazardous waste. Also, using
Picklex® eliminates numerous rinsing steps,
which means less floor space is needed for rinse
tanks. Other advantages of the Picklex® process
include easy agitation of the solution, slow
evaporation rate, and operation at ambient
temperatures.
51
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Commercial Pretreatment
joroaje Conversion Coat
, *,'?• «"c;-"«Kr-> r' i
Commercial Pretreatment
Picklex® Pretreatment Zinc Phosphatizing
Conversion Coat Conversion Coat
S":«iS1tf Comparison of the
'I steps required for
BK^wHtsv-ruf two conventional
^.5f.,r .r-^-'^3^>:-:!t?:i|
pretreatment
!Ly^ processes with
Picklex®
pretreatment.
52
,
ij^^
L'' ..... '
toPowder Coating
Worker spraying powder
coat on test panels.
-------
LOW-POLLUTION POLYMER
SYNTHESIS
Polymers, complex molecules made up of
repeating subunits, are used in plastics,
advanced microelectronics, optics, ceramics,
and many other useful products. Historically,
high-performance polymers have been produced
using methods requiring hazardous organic
solvents under very carefully controlled reaction
conditions. A new procedure, called atom
transfer radical polymerization (ATRP), is being
developed by EPA grant recipients at Carnegie
Mellon University. ATRP is a simple,
inexpensive, and innovative technology that
produces polymers with a variety of specific
features. The process either uses minimal
amounts of hazardous solvents or completely
replaces them with safer, more environmentally
friendly solvents. ATRP has attracted intense
interest from industry; four corporate licenses
have been signed, granting permission to use
ATRP commercially, and two industrial
consortia have formed to define the scope and
explore the limitations of ATRP and similar
technologies.
ORD scientist demonstrating a biosensor method to
measure environmental pollutants.
WASTE-REDUCING TECHNOLOGY
FOR GROUNDWATER
Volatile chlorinated solvents have been
used widely as industrial degreasing, cleaning,
and dry cleaning agents for decades. In the past,
disposing of these solvents involved pouring
them on the ground and allowing them to
evaporate. However, much of the solvent
infiltrated the soil rather than evaporating as
expected. Over time, heavy chlorinated solvents
seep into groundwater, forming pools that persist
vVWWVW
Linear
1,/ViA/yVi'VAA
\A
Star'
Multi-Armed GraWComb Polymers Networks (Hyper)Branched
A polymer's composition and architecture, such as the forms shown here, determine its physical and
mechanical properties.
53
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Scientists working at the pervaporation field
demonstration site.
for many years and that serve as ongoing sources
of contamination. Many of these chlorinated
solvents are either known or suspected to cause
cancer.
ORD scientists participated in a
successful field demonstration of a new
technology called pervaporation, a
process enabling the recovery and
recycling of a water-based remediation
fluid used to remove chlorinated solvents
from contaminated soil. The
pervaporation technology removed
volatile contaminants from the
remediation fluid and ultrafiltration
technology concentrated the surfactant,
which was added to facilitate extraction
of the solvent from soil. This procedure
allows up to 95 percent of surfactant in the fluid
to be recovered and reused, reducing surfactant
costs by approximately 80 percent. In addition,
because the surfactant is reused and not
discarded with the contaminants, disposal costs
are greatly reduced.
Schematic diagram of the integrated below-ground extraction and above-ground surfactant recovery-and-
recycling processes.
Surfactant
Water
t
Chlorinated
Solvent
Ultrafiltration
Unit
bi '••'••' ""•««is iifcHfe^Milisd
eerworftioni
VS.-. : • j-els^W&t$$fla
K^UBB^W
lit
54
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ENVIRONMENTAL TECHNOLOGY
VERIFICATION PROGRAM
On October 1, 2000, EPA's Environmental
Technology Verification (ETV) Program began
operation as a full-scale program following a
five-year pilot period. The Program was created
to verify the performance of innovative
technologies developed to prevent or solve
environmental problems. ORD manages this
Program, which operates through public-private
testing partnerships to evaluate the performance
of commercial-ready environmental
technologies. By providing independent and
credible information about the verified
technologies, the Program accelerates the
entrance of new environmental technologies
into both domestic and international
marketplaces. Technology purchasers and
government officials who authorize use of
technologies at specific remediation sites report
that information provided by the ETV Program
helps them decide which technology is
appropriate for each situation.
A major accomplishment of the ETV
Program is development of uniform tests and
protocols to evaluate new technologies. To date,
the Program has produced over 90 test plans and
60 generic protocols-all of which are peer
reviewed and available to the public on the
Program's web site. These test procedures are
now used far beyond the borders of the United
States. For example, India and Bangladesh are
using the Program's protocols to identify
technologies capable of addressing their very
In 2001, ORD purchased two new electric cars for use by
security officers and facility maintenance personnel at the
Research Triangle Park location.
serious problems with arsenic in drinking water.
An international consortium lead by Japan is
evaluating an ETV Program protocol for testing
baghouse filtration products for potential use as
an international standard. The recently issued
New Zealand drinking water standards refer to
Program protocols for rmcrofiltration
technologies.
: '• "eclinologles evaluated ,by:th)e JEIV^,;;,, :I:
Program include; those for .;v.;. • \;; .., ' .'.^i
h* reducing nitrogeW cjxjdq i ©Mssions tty ;
•;-; using altefriative/fuefen^
•if * rest-time monitoring of pollutants in aitT
'preventing leaks M greenhouse gases
; • :• I rcjrn :nMufa:l;£ia^ pipelines^ ;; ; ;^ ; -l -:;:- ;
" «--. eonteoJIfng 6ryptosp6rfdjum arid '-^
: *: -. arsenic in small community drinking y
^"Water Systems ^ and ;^; "-: •^':U"- '^^:
^vi^ducing yglatile organfejCompounti ;: 5
V iV0C) emissions frprfi suffa^cQalng
55
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Assessing water quality near a Superfund site.
In 2001, the ETV Program completed 82
technology tests and reports, bringing the
cumulative total to 164 verifications since 1995.
The technologies span a broad range of
categories including environmental monitoring,
air pollution control, drinking water protection/
treatment, greenhouse gas control, water
protection, and pollution prevention. Also in
2001, EPA signed Memoranda of Agreement
with the U.S. Department of Defense, the U.S.
Coast Guard, and the Commonwealth of
Massachusetts to conduct joint verifications. In
keeping with its objective to widely distribute
information about new technologies, ETV
Program representatives presented information
at over 60 national and international
conferences. In its short life, this Program has
become the most comprehensive environmental
technology verification program in the world.
SUPERFUND INNOVATIVE
TECHNOLOGY EVALUATION (SITE)
PROGRAM
In response to the Superfund Amendments
and Reauthorization Act, EPA's Superfund
Innovative Technology Evaluation (SITE)
Program was established by the Office of Solid
Waste and Emergency Response and ORD.
Administered by ORD, the SITE Program offers
a mechanism for conducting joint
demonstrations and evaluations of innovative
technologies at Superfund sites. ORD invites
partners from across EPA, other federal and state
agencies, and the public sector to participate in
these projects. The SITE Program is not a
pollution prevention activity per se; rather, its
primary purpose is the expedited cleanup of the
Nation's most contaminated sites.
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The SITE Program
encourages the development
and implementation of
innovative technologies for
hazardous waste cleanup
and for monitoring and
measurement.
Since the SITE Program began in 1986,
cleanup of contaminated sites using innovative
technologies has resulted in a total cost savings
of over 2.4 billion dollars. The
SITE Program is recognized as a
leader in advancing innovative
technology development and
commercialization. In 2001,
146 remediation technology
vendors participated in the
program. Also in 2001, the
Environmental Council of
States (EGOS) acknowledged
the SITE Program for its efforts
in demonstrating innovative
technologies and their
associated cost savings.
EGOS champions the efforts of
its fifty-two member states and
territories in achieving better
environmental protection
through the use of innovative
technologies.
LOOKING TO THE FUTURE
Milestones that will be reached in the near
future include
• ten new stakeholder'approved, peer-reviewed
protocols for testing new technologies under the
Environmental Technology Verification
Program,
• an international conference on clean production
technologies hosted by ORD,
• a state'of'the'Sdence report on bioengineering
for pollution prevention, and
• new methods for evaluating conventional
agricultural production and agricultural
biotechnology from an environmental
management perspective.
57
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HI ,!•> w^sahjjwii; A,, 5 .iavr;, :,r;^
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In recent years, EPA has been moving
beyond environmental regulation to
environmental protection in a broader sense,
anticipating and preventing problems before
they mushroom into major concerns. To support
EPA in this endeavor, ORD conducts research
on 'Emerging Issues,' anticipatory activities that
fall within the mission of EPA, but are not being
addressed in ORD's major research programs.
Two such issues are endocrine-disrupting
chemicals and environmental socioeconomic
values.
pesticides and industrial chemicals, are either
known or suspected EDCs.
ORD is a world leader
in EDC research.
Because of the global scope of the EDC
problem, the possibility of serious problems in
humans and wildlife, and the persistence of
some EDCs in the environment, research on
EDCs is a high priority at ORD. ORD leads an
international committee that is conducting a
ENDOCRINE-DISRUPTING
CHEMICALS
In the last decade, the scientific community
has become increasingly concerned that humans
experience health problems and wildlife
populations are adversely affected following
exposure to chemicals that interact with the
endocrine (hormonal) system. The endocrine
system plays a critical role in normal growth,
development, reproduction, and behavior.
Disruptions in hormonal balance at critical life
stages may have long-lasting effects. Chemicals
that interfere with the function of the body's
natural hormones are called endocrine-
disrupting chemicals (EDCs). A broad range of
environmental contaminants, including some
global state-of'the-science assessment of EDCs
and a national working group that coordinates
EDC research among multiple federal agencies.
ORD's multidisciplinary EDC research addresses
critical gaps in our understanding of how people
and wildlife are exposed to EDCs in the
environment and the health and ecological
effects of such exposures. The information
gained in this research program will directly
support EPA risk assessments and risk
management activities.
EDC Screening and Testing
The Food Quality Protection Act and Safe
Drinking Water Act Amendments mandate that
59
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EPA develop an EDC screening and testing
program to evaluate chemicals found in food
and drinking water. EPA's Endocrine Disrupter
Screening Program develops and validates
ORD scientists have developed a screening test using
fathead minnows that identifies reproductive
disruptions resulting from exposure to chemicals.
methods and procedures used to detect and
characterize the endocrine-disrupting activity of
pesticides, industrial chemicals, and
environmental contaminants. These protocols
will help EPA and industry efficiently gather
information regarding endocrine-disrupting
activity for the estimated 87,000 chemicals in
commercial use.
ORD scientists play a major role in
developing these testing protocols. As of 2001,
ORD researchers have developed or are
developing
• protocols to identify chemicals that change the
age of puberty in male and female rats,
• screening tests to identify substances that mimic
or interfere with male hormones,
• methods to assess the effects of chemicals on
reproduction and on f>re- and postnatal
development in mammals,
• procedures for detecting chemically induced
reproductive problems in fish and invertebrate
animals, and
• tests to identify chemicals that interact with
locations in cells where hormones bind to cells.
In addition to laboratory tests, ORD
scientists are developing computer models that
predict a chemical's effect on biological systems
based on its molecular structure. These models
will provide a means to rapidly and cost-
effectively screen large numbers of chemicals for
structural features likely to be associated with
endocrine-disrupting'activity. Chemicals
identified by these models as possible EDCs can
then be evaluated using one of the biological
screening methods listed above.
These three-dimensional diagrams show the
structural similarity between two compounds,
When a structural characteristic is associated
with endocrine-disrupting activity, a computer
model can be used to identify other'
compounds with similar structural features.
60
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EDO Toxicology
A major area of ORD research addresses
chemicals that either mimic, enhance, or block
the action of male hormones. Chemicals that
exhibit any of these effects include phthalate
esters (used widely in the manufacture of
plastics) and several pesticides. When exposed
to these chemicals, laboratory animals have
developed numerous developmental problems
including undescended testes, malformation or
lack of sexual organs, and cancer-like testicular
lesions.
In 1999, ORD investigators reported that
exposure of pregnant and nursing rats to
atrazine, a widely used agricultural herbicide,
increased the risk that male offspring would
suffer from inflammation of the prostate gland as
adults. In 2000-2001, ORD toxicologists used
two of the newly developed screening protocols
to determine that
atrazine delayed the
onset of puberty in both
male and female rats.
Using the same
protocols and an
expanded range of
doses, ORD scientists
were able to
characterize the
relationship between
dose and response for
this toxic effect, an
ability that had not
been anticipated when
An ORD toxicologist
conducting research.
the protocols were developed. EPA's Office of
Pesticide Programs incorporated the results from
this research on atrazine into the latest human
health risk assessment, which was used to
determine the level of atrazine residue permitted
in foods.
ORD toxicology and
epidemiology studies have
found that exposure to
BPCs can alter the age at
which puberty is reached.
EDC Epidemiology
In 2000, scientists working under EPA's
Science to Achieve Results (STAR) grant
program reported results of an epidemiologic
study on the effect of polybrominated biphenyl
(PBB) on the age at
which girls reach
puberty. Following an
industrial accident in
Michigan in which a
PBB-containing fire
retardant was
inadvertently added to
livestock feed, health
authorities established
a registry of residents
exposed to meat and
dairy products
contaminated with
PBB. Daughters of
61
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women listed in this registry who were born
during or shortly after the incident were eligible
for the study. The researchers found that
breastfed girls ex]36*sed to high levels of PBB
before birth were approximately six to twelve
months younger when they started their periods
«$&
than breastfed girls exposed to lower PBB levels
before birth or girls who were not breastfed.
..#..;
EDO Risk Management
ORD recently launched a new risk
management research activity focusing on
several types of compounds that are known or
suspected EDCs. A team of scientists from ORD
and EPA's program offices are collaborating with
outside researchers to address two major
questions:
• Can die application of currently available risk
management tools successfully manage the risk of
exposure to EDCs in a cost-effective manner?
• As more information about EDCs becomes
available, whal'hew tools will we need to manage
the risks associated with, exposure to EDCs?
This research program includes scientists
within and outside of ORD and EPA who are
laying the groundwork for future research in this
area. Recent accomplishments include
publication of Removal of Endocrine Disrupter
Chemicals During Drinking Water Treatment,
completion of the draft document Risk
Management Evaluation of Endocrine Disrupting
Chemicals, and coordination of a workshop
where experts identified and evaluated effective
risk management strategies for EDCs.
ENVIRONMENTAL SOCIOECONOMIC
VALUES
While of undeniable benefit to the nation's
citizens, virtually all regulatory activities impose
costs on the public. Understanding how to
evaluate the costs and benefits associated with
environmental decision making is another
emerging research area at EPA.
Eliciting an individual's true
preferences is one of the
most important features of
survey design.
Working under a STAR grant administered
by ORD, a researcher at the University of
California-San Diego studied various survey
formats that are used to assign an economic
value to environmental assets such as clean air,
clean water, and the cleanup of sites
contaminated with toxic or hazardous
substances. The research explored incentive'
62
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compatible preference surveys, which are
designed to provide survey participants with
incentives to truthfully and fully reveal their
preferences on the subject of the survey. EPA is
using the findings of this research to develop a
handbook for agencies and organizations that
conduct preference surveys on environmental
issues. For instance, these types of surveys can
be used to assign economic value to
environmental resources-such as wilderness
areas and haze-free vistas at scenic locations-
and policies that protect human health, such as
air pollution control regulations. This new
information can help EPA and state policy
analysts evaluate and articulate the costs and
benefits of environmental programs.
LOOKING TO THE FUTURE
Anticipated accomplishments in ORD's research
on emerging environmental issues include
• new and improved biological and computational
screens and tests for EPA's EDC screening and
testing program;
• a better understanding of the impact of EDC
exposures during development on the onset and
severity of health problems later in life;
• an evaluation of the usefulneTs offish, reptile,
and. bird species as indicators of the presence of
EDCs in the environment; and
* a determination of the extemvf sources-such as
combustion operations,
animal feedlots, and
wastewater treatment
plants-that can expose
people to EDCs.
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For more information, please access the
Office of Research and Development website at:
www.epa.gov/ORD
This document is available on ORD's website at:
www.epa.gov/ORD/publications
Paper copies of this and many other EPA publications may be
ordered from the National Service Center for Environmental
Publications (NSCEP) by telephone at 1-800-490-9198
or online through:
www.epa.gov/epahome/publications.htm
The information provided in this report does not constitute an
endorsement by the Environmental Protection Agency of any
non-Federal entity, its products or services.
United States Environmental Protection Agency
Research and Development (8101)
EPA/600/R-01/094
April 2002 . =-- ^"
http://www.epa.gov '••
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