Unrted States
Environmental Protection
Agency
Office of Research and
Development
Research Triangle Park, NC 27711
ERA/600/R-00/079
August 2000
http://www.epa.gov/nheerl
v>EPA
National Health and
Environmental Effects
Research Laboratory
Human Studies Division
Investigating the Environment's
Impact on Human Health
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:PROTECTING
rHUMAN
HEALTH
;• Epidemiologists study whether poten-
i dally susceptible subpopulattons, such
| as the elderly (right) and children
" (below), arc at a greater risk than the
I general population of experiencing
>: adverse health effects from environ-
mental pollutants.
studies. However, the extrapolation of
in vitro and In vivo animal toxicology
data is complicated by factors unique
to humans, such as long life span, the
presence of pre-existing diseases, and
high inter-individual variability.
The mission of the U.S. Environmen-
tal Protection Agency (EPA) is to
protect human health and safe-
guard the natural environment-
air, water, and land - upon which
life depends. ERA'S National
Health and Environmental Effects
Research Laboratory (NHEERL)
supports the Agency's regulatory
decision-making process by
investigating potential risks that
environmental contaminants
may pose to humans and eco-
systems.
Much of this effort is achieved
through controlled animal
To provide directly applicable human
data as well as to facilitate the
extrapolation of nonhuman data, the
multidisciplinary staff of NHEERL's
Human Studies Division (HSD)
conducts a coordinated research
program that integrates epidemio-
logical, clinical, and laboratory-based
studies.
Using sophisticated equipment
that concentrates outside air
particles (right), scientists study
the effects of exposures to these
particles (left) at concentra-
tions commonly encountered in
large urban areas.
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"Through this integrated approach, HSD
continues to inform EPA's regulatory
standard-setting process for air and
water pollution, and pesticide control.
In addition, HSD often collaborates
with other EPA scientists as well as
researchers in other government agen-
cies, universities, and international
organizations to obtain needed data.
For example, collaborations between
HSD and the University of North
Carolina's Center for Environmental
Medicine and Lung Biology (CEMLB)
have generated human data that
directly influenced the setting of air
quality standards by demonstrating
that:
• People with vascular heart
disease have an increased
sensitivity to carbon monoxide
• Asthmatics have an increased
sensitivity to ozone
• Air pollutants may induce ad-
verse health effects through a
variety of subcellular (molecular)
mechanisms
The staff in the Subject Recruitment Office
(below) enroll volunteers to study the acute
effects of low-level exposures to common
environmental pollutants.
A field scientist (above) evaluates house-
hold dust as a potential source of pesticide
exposures.
THROUGH
HIGH
| QUALITY
F RESEARCH
|L Geographic information systems allow
jj investigators to determine whether
p there is an association between the
j* spatial distributions of adverse health
f" effects and environmental pollutants
t Oeft).
B
IP-
AQ electron micrograph of the
lining of a bronchus (above)
reveals air pollution particles
(dark granules) embedded
between the hair-like cilia. The
presence of a spherical mucoid
droplet is typical.
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EPIPEMIOLOGICAL
STUDIES
An Epidemiologist (right)
analyzes blood parameters to
determine whether the eld-
erly are especially sensitive
to the adverse health effects
of air pollution particles.
subpopulcrhons, including:
• The elderly
People with pre-existing
health conditions
Infants and chi dren
These studies involve analyses of
existing health databases as well as
new investigations using cohort,
cross-sectional, and panel designs.
Health effects of interest include:
In a field study in Inner
Mongolia (above), collabo-
rating scientists use a global
positioning system to deter-
mine the distribution of ar-
senic-contaminated wells.
The epidemiology program evaluates
the relationship between real-world
exposures to environmental contami-
nants and adverse health effects.
Environmental contamination may
result from:
• Natural occurrence (e.g.,
arsenic in drinking water)
• Residential and industrial
discharges into the air and water
• Treatments intended to ensure
food and water quality (e.g., by-
products from water disinfection)
• Agricultural practices (e.g.,
pesticide contamination)
HSD conducts national and interna-
tional field studies, many of which
focus on particularly sensitive
• Cardiovascular disease
• Respiratory disease
• Reproductive & developmental
abnormalities
• Neurological disease
• Cancer
• Infectious disease
HSD also conducts
epidemiological studies
to investigate the
incidence of drinking-
water contamination by
mioxDorganisms, such as
Cryptosporidium (left)
and Giardia (right),
which can cause severe
gastrointestinal illness.
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CLINICAL
STUDIES
Clinical physiology equipment,
which looks similar to exercise
equipment (right), is used to
measure the effects of air pol-
lutants on lung function.
Prior to conducting any human
exposures, volunteers are care-
fully screened by trained health
professionals (below).
The Human Studies Division complies with
the requirements of the "Common Rule"
to ensure that its clinical studies in-
volve short-term, real-world expo-
sures conducted in a safe and ethi-
cal manner. Using state-of-the-art
technology, human volun-
teers are exposed under
controlled conditions to
ambient concentrations of
common environmental
pollutants, such as:
• Air particles
• Ozone
• Hazardous air pollutants
• By-products from water
disinfection
• Fuel additives
Using sophisticated non-invasive instruments like gamma cameras
(above), scientists can study how microscopic air pollutants deposit
in the lungs (insetX:
The health effects of these pollutants
are then measured along a wide range
of physiological parameters, including:
• Respiratory function
• Respiratory tract dosimetry
• Cardiovascular function
• Neurobehavioral effects
• Pharmacokinetics
• Cellular/molecular processes
• Immune status, including
allergic response
y.._—s
A specially designed pharmacokinetic chamber
(above) allows investigators to periodically
sample a volunteer's blood during a one-hour
controlled exposure to determine how the body
absorbs and eliminates environmental pollut-
ants.
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STUDIES
Electron microscopy (right) is used
to obtain high resolution images,
such as an epithelial cell dividing
In culture (below). Such images
permit detection of subtle struc-
tural changes in cells following
exposure to environmental toxi-
cants.
To understand how environmental
contaminants induce adverse health
effects at the tissue, cellular, and
subcellular levels, HSD scientists also
expose human cell cultures to pollut-
ants and look for:
Evidence of cellular injury,
inflammation, and repair
Integrity of host defense
mechanisms
Altered gene expression
Changes in cellular com-
munication pathways
HSD scientists also develop and vali-
date biomarkers of exposure, effect
and susceptibility. Such efforts facilitate
extrapolation of nonhuman data and
improve epidemiological assessments
of exposure and health effects.
Currently, HSD is developing biomarkers
to assess:
• DMA damage from ambient air
particles
• Exposure to arsenic found in
drinking water
• Pesticide exposure in children
• DNAadductformation
• Exposure to microbial pathogens
Computer-assisted image
analysis is used to measure
subtle changes in human
tissues, such as lung
sections (right), that may
result from exposure to air
pollutants.
A visiting scientist (above) uses molecular
biology techniques to investigate how
pollutants niay disrupt cell function.
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FOSTERING
INTERACTIONS
HSD and the unique research
facilities depicted in this brochure
are located in the Human Studies
Facility on the medical campus
of the University of North Carolina
(UNC) at Chapel Hill. Comple-
menting its research capabilities,
the Facility's offices and varied
meeting places- including a main
seminar room, library, and four
conference rooms - encourage
collaboration and the free ex-
change of ideas with scientists at
. local universities as well as other
research institutions throughout
Research Triangle Park.
l!
CONTACT
INFORMATION
For more information about research programs in the Human Studies Division and
the availability of facilities for use by non-EPA scientists conducting research in the
public interest, please contact:
Ipfficeofthebirector
ilHuman Studies Division
'J&, , : : - ' " -'"- ' ;•-•;-•-•-•-• ' -••• ...:••
IIPA/NHEERL
...... .......... "
^Research Triangle Park, NC 2771 1
^Telephone: (9 19) 966^5200
[Fax: (919;) 966-621 2 , _;
f|mafl: Hs^.rrp-hsd@epa.gov
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1 FACILITY
LOCATION
i -
The Human Studies Facility (HSR) is located at 104 Mason Farm Road in Chapel
Hill, North Carolina. Also located in the facility is UNC's Centerfor Environmental
Medicine and Lung Biology (CEMLB), with whom HSD conducts some of its
collaborative studies. In total, the HSF is occupied by almost 100 scientific and
administrative staff.
Some of the photographs In this brochure"
depict non-EPA employees performing work
under contract or through a cooperative i
agreement with the EPA.
Printed on Recycled Paper
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