U.S. Environmental Protection Agency
Office of Research and Development
September 2001
NATIONAL EXPOSURE RESEARCH LABORATORY
JSTERI, 3001
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Volume 4, Issue 3
In This Issue
Click On A Topic
Research
Blazing New Trails
EPA Continues RAP with
Shaw
Source-to-Dose Modeling
More Research
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TIS Turns Two
HPO Update
NERL Notables
NERL Sponsors NAFEO
Faculty Development
and Student Intern
Opportunities
Reaching Out in Las Vegas
More Notables
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Task Information
Integration: The NERL Researcher's
Key to Discoveries and Innovations
That Drive a Revolution in
Environmental Decision Making
Gary
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The take home message about the Risk Assessment - Risk
Management - Accountability paradigm is worth restating,
and I hope that it generates scientific discussion among the
researchers within and outside of the NERL.
As progress is made, we all
will better understand the
important knowledge gaps
that our research needs to
address so that environmental
decisions have the greatest
possible positive impact on
human health and ecological
endpoints.
The risk assessment process helps us understand the ef-
fects mechanisms that either form the basis of the risk to
human health or that are associated with the ecological
endpoints of concern that form the basis of the risk. The
risk assessment process may also help us understand the ex-
posures and/or ambient pollutant levels associated with these
effects. The risk assessment process additionally helps us
understand the pathways of exposure from ambient pollutant
levels that lead to personal exposures or the pathways of ex-
posure that link the ambient pollutant levels to both ecologi-
cal stressors and effects.
Risk management decisions generally lead to actions to
reduce pollutant levels in the environment; however, account-
ability brings in new considerations. Desired pollutant levels
may be achieved through many combinations of reduction
actions. Each combination of these actions, while achieving
the desired levels, may bring about different changes in mor-
bidity and mortality or in ecosystem endpoints. Accountabil-
ity requires that the decision maker take into account not only
how the pollutant levels will change, but also how the mor-
bidity and mortality of the population or the ecosystem end-
points will change. Models and measurements that support
the decision makers will need to go beyond looking strictly at
pollutant levels so that potential changes in morbidity and
mortality or in ecosystem endpoints can also be considered.
Ultimately, accountability needs to be based on improving
the morbidity and mortality and the ecological endpoints.
This will require measurements of personal exposure/expo-
sure pathways/population effects and the ecological stres-
sor-response relationships to identify the causal links to the
risk management actions that explain the trends in these
measurements and endpoints.
At the individual researcher's level, integration occurs
across disciplines through coordination, cooperation, and
collaboration. At the Laboratory level, the NERL's senior
managers and I will be working with our counterparts in
ORD and the Agency through the Multi-year Planning
effort to identify places where integration will add value.
With your help we can carry out new and far-reaching part-
nerships that will foster integrated research for the greatest
impact on the decisions, actions, and regulations that safe-
guard the natural environment and protect human health. I
hope all of you will discuss this within your branches, teams,
and beyond. All of NERL's managers look forward to fur-
ther discussions with you as we move ahead.
Blazing New Trails
The NERL Environmental Sciences Division is blazing
new trails with its ongoing outreach efforts regarding envi-
ronmental aspects of pharmaceuticals and personal care
products (PPCPs). Recent efforts include the publication of
a book on PPCPs by the American Chemical Society (ACS)
and Oxford University Press.
Edited by Christian Daughton and Tammy Jones-Lepp, the
book is one of only two that have addressed this topic, and
both were published in summer 2001. The book is the result
of a proposal submitted by Daughton and Jones-Lepp to the
ACS to produce a symposium series book that captured and
expanded on the proceedings of a symposium organized for
the 219th National Meeting of the ACS last spring.
The symposium, "Pharmaceuticals and Personal Care
Products in the Environment: An Emerging Concern," was
organized and co-chaired by Daughton and was the first all-
day symposium in North America on PPCPs in the environ-
ment.
The book's final chapter breaks new ground in applying the
current body of knowledge on the occurrence of therapeutic
drugs in the environment by opening a window onto what
has long been an aspect of society that has proven difficult to
accurately assess — the magnitude and extent of illicit drug
use. The use of sewage-influent monitoring is proposed as a
non-intrusive means of calculating illicit drug usage on a
community-wide scale; this is the first truly new approach to
this much-debated issue to be put forth in decades.
The table of contents, preface, and two chapters written by
Daughton are available at: http://WWW.epa.gOV/nerlesdl/
chemistry/pharma/book.htm
Christian Daughton, NERL-Las Vegas, (702) 798-2207
NEKL Task #6980*
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Building Links: Source-to-Dose Modeling
The third annual meeting of the ORD University Partner-
ship Agreements for source-to-dose human exposure model-
ing was hosted by the NERL in Research Triangle Park,
North Carolina in August 2001. It included presentations by
15 researchers, scientist-to-scientist discussions, and a meet-
ing to discuss future plans. This collaborative research pro-
gram began in FY99 when five-year agreements were
competitively awarded by the NERL to the Lawrence Berke-
ley National Laboratory and the Environmental and Occupa-
tional Health Sciences Institute.
The purpose of this joint research program is to develop
and refine an integrated modeling framework with modular
components to predict exposures and doses of individuals,
populations, and susceptible subpopulations to important
classes of environmental pollutants. Such a modeling frame-
work will be an invaluable tool for decision makers in priori-
tizing pollutant classes for future measurement studies and
regulatory activities.
The modeling framework links together modules character-
izing source emissions, multi-media transport, environmental
and micro-environmental concentrations, human activity pat-
terns as related to pollutant concentrations, multi-pathway
exposures, and doses. Rather than emphasizing new model
development, the focus is on building links between inputs
and outputs of models for the entire series of processes from
source to dose. Where existing models are not sufficient,
new models are being developed to fill gaps in the modeling
framework. Since this program began, efforts have been
made to work with other interested laboratories and program
offices to incorporate their modeling activities and needs into
the research planning process.
Haluk Oyjkaynak, NERL-RTP, (919) 541-5172
NERL Task #3948*
Plume-in-Grid Photochemical Modeling
Scientists at the NERL Atmospheric Modeling Division
have been hard at work updating and testing the Plume-in-
Grid model of major point-source emissions. The plume-in-
grid (PinG) treatment, originally designed to simulate the
dynamic and photochemical processes of gaseous pollutants
in point-source plumes within the Community Multiscale Air
Quality (CMAQ) modeling system, has been upgraded to also
model aerosols and particulates. The aerosol model approach
currently employed in the CMAQ chemical transport model
has been incorporated into the PinG algorithm to make it
capable of treating aerosol processes in plumes. Code testing
of the upgraded PinG gas/aerosol model is underway and
simulations are planned in order to compare model results
with various particulate/aerosol plume measurements.
Selected results from simulations were presented at the
American Meteorological Society Symposium on
Atmospheric Chemistry. Modeled results for various gaseous
species were compared against pollutant data collected by
research aircraft during airborne traverses across power plant
plumes at various downwind distances. The evolution of
modeled plume ozone and oxides of nitrogen (NOX)
concentrations displayed the same behavior as in the
observed plume data collected by the research aircraft. The
ozone recovery and the rate of NOX oxidation in modeled
plumes were strongly related to the NOX emission rate, which
were also found in the plume measurements.
James Godomtch, NERL-RTP, (919) 541-4802
NERL Task #3873*
Cooperative R&D
In June, a cooperative research and development
agreement was signed between Fluent, Inc. and the NERL.
The goal is to help make Computational Fluid Dynamics
(CFD) a proven and applied tool to support air pollution
concentrations modeling within building and roadway human
exposure microenvironments. This will be achieved through
the following:
a) Comparison to experimental data and to other
established methodologies used for environmental
exposure modeling;
b)Identification of desirable custom software tools that
would simplify the CFD process for environmental
scientists and reduce the risk of user error in its
application;
c) Determination of best-practice methodologies that
document the recommended usage of CFD software for
environmental exposure modeling; and
d)Identification of research topics and future software
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development that should be pursued in order to extend
the state-of-the-art in CFD modeling of environmental
exposure to air pollutants.
Some preliminary results of evaluation studies and an
outline of research plans were presented at the annual Air
and Waste Management Association Conference in June
2001. Application should start by demonstrating that CFD
results are comparable to an appropriate set of base-case
situations that are supported by measurement data and,
perhaps, non-CFD analytical solutions. It is recommended
that these base cases be established through a working group
of commercial and government CFD practitioners. Standard
cases for different types of microenvironments (e.g., a
roadway or a building cluster) would be based on databases
from field and wind tunnel studies.
Alan Huber, NERL-RTP, (919) 541-1338
NERL Task #9524*
Release of Models-3/CMAQ Version 4.1
The NERL Atmospheric Modeling Division has released
version 4.1 of the Models-3/CMAQ (Community Multiscale
Air Quality) modeling system. The emission modeling sys-
tem has been replaced with a more flexible and efficient mod-
eling system. A tool has also been added for creating input
files using SAS and Arclnfo software. Other improvements
have been made to correct known problems, to add new sci-
ence options, and to improve the speed of the simulations.
Models-3/CMAQ for the Sun workstation has been
shipped to users who are able to process Digital Linear Tapes
(DLT), and a copy of the installation manual has been
shipped with each copy. Version 4.1 will be shipped to Sun
users without DLT. Version 4.1 for Windows NT is com-
plete, and the installation CD-ROM and manual are being
prepared. As before, the NT version will be distributed by
the National Technical Information Service, although patches
for those who have installed version 4.0 will be distributed by
the Models-3 help desk.
Gary Walter, NERL-RTP (919) 541-0573
NERL Task #3873*
Chiral Chemistry in the Environment
An Annual Performance Measure Report to the Office of
Pesticide Programs was delivered that describes the results of
research by the NERL Ecosystems Research Division on
chiral chemistry in the environment. We ordinarily think that
the diagram of a molecule's structure shows everything about
the way the atoms connect to make a specific chemical with
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defined properties. However, with some molecules, a careful
look at their three dimensional structure offers a surprise —
there are two ways to connect the atoms. These are called
chiral molecules, or chiral chemicals, from the Greek cheir
(hand), because, like hands, the two forms of the molecule
are non-superimposible mirror images of each other. These
two species are called enantiomers. Up to 25% of pesticides
are chiral, existing as two enantiomers that are non-
superimposable mirror images of each other. Enantiomers
usually interact with enzymes or other chiral molecules selec-
tively; this enantioselectivity often results in different rates of
microbial/biological transformation and differences in toxic-
ity of the two enantiomers. The enantiomers of chiral pesti-
cides should be treated as separate compounds; accurate
environmental and human risk assessments require an under-
standing of the relative persistence and effects of each enan-
tiomer.
In this report, the fungicide metalaxyl was shown to be
degraded enantioselectively by microbes in an aerobic envi-
ronment in laboratory microcosms — the half life for disap-
pearance of one enantiomer was 11 days while the other was
63 days. In addition, a racemic formulation of the herbicide
metolachlor applied to a watershed was shown to have de-
graded enantioselectively after 2 years; in soil at depths below
21 feet the residual metolachor was greatly depleted in the
(R)-enantiomer, suggesting considerable anaerobic biotrans-
formation. Preliminary results from experiments with food
extracts showed that the incurred malathion in a sample of
blackberries was enriched in the (-)-enantiomer, while in-
curred or-permethrin in spinach was slightly enriched in one
of its enantiomers.
Wayne Garrison, NERL-Athens, (706) 355-8219
NERL Task #6519*
United States-Mexico Transboundary
Air Pollution Studies
A recent special issue of The Science of the Total Environment
(Vol. 276, Nos. 1-3; 2001), guest edited by Dr. Shaibal
Mukerjee of the NERL Human Exposure and Atmospheric
Sciences Division, presents transboundary air pollution stud-
ies in the U.S.-Mexico border region. The introduction by Dr.
Mukerjee details environmental and North American Free
Trade Agreement (NAFTA) policy issues for the region dur-
ing the 1990s. The introduction summarizes the thirteen pa-
pers presented in the issue, and provides a quantitative
technique on how air pollution trends can be analyzed with
economic information, such as the increase in truck/car-
crossing data; it also provides figures for border industries
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known as maquiladoras during this period. The thirteen pa-
pers deal with air-quality indicators related, in part, to popula-
tion growth, cross-border traffic, and economic expansion
since ratification of NAFTA. The regions covered span from
Tijuana, Baja California to Brownsville, Texas. Many of the
air pollution assessments presented in this issue have made
national headlines in the U.S. (e.g., visibility degradation at Big
Bend National Park, Texas and exceedances for ozone in the
Paso del Norte region). Most of the studies have been spon-
sored by binational initiatives such as the La Paz Agreement
and U.S.-Mexico Border XXI Program. This special issue
should be of use to environmental scientists, managers,
policy makers, and public interest groups who are attempting
to assess border air quality conditions that may be conse-
quences of NAFTA initiatives.
ShaibalMukerjee, NERL-RTP, (919) 541-1865
NEKL Task #643
USDA Award for Excellence
In June the U.S. Department of Agriculture Award for
Excellence was presented to the
Semi-Arid Land-Surface-Atmo-
sphere Team (William G. Kepner,
K. Bruce Jones, Daniel T Heggem,
and Curtis M. Edmonds) for lead-
ing a multi-agency effort to provide
critical, hydro-ecological information
and new measurement tools for sustaining
our precious semi-arid natural resources.
U.S. Global Climate Observing System
National Report
An exciting example of ORD-wide and cross-agency coop-
eration is the creation of the Global Climate Observing Sys-
tem (GCOS) National Report that looks at uses of future
satellite remote sensors. Led by the National Oceanic and
Atmospheric Administration (NOAA), this dialogue exam-
ined all the potential uses of marine and coastal applied sen-
sors. Dr. Gary Foley identified this as a NERL opportunity
through his understanding that marine sensors often have
nearshore, terrestrial, and/or Great Lakes applications. Dr.
Foley contacted John Lyon to arrange for the NERL contri-
bution to the report. Other ORD contributions included Hal
Walker, National Health and Environmental Effects Labora-
tory, who led the dialogue with Dr. Lyon's help, and Michael
Slimak, National Center for Environmental Assessment, who
approved the EPA contribution. This detailed report pro-
vides an interesting means for readers to understand current
and future uses of remote sensors. The report demonstrates
a good consensus on the Federal missions that can be met
through satellite remote sensors.
The report is available at: ftp://ftp.esdim.noaa.gOV/pub/gCOS
Communicating Our Science
The Journal of the American Society for Mass Spectrometry has
published an article by Christian Daughton, NERL Environ-
mental Sciences Division, that attempts to tie together three
topics — the importance of communicating science, the cen-
tral importance of mass Spectrometry to environmental sci-
ence, and how both of these relate to the emerging field of
pharmaceuticals and personal care products (PPCPs) in the
environment. Daughton was encouraged to write this article
following a keynote presentation at a session on Emerging
Contaminants at the 49th American Society for Mass Spec-
trometry (ASMS) conference. Daughton's main objective was
to provide the ASMS with a marketing or outreach tool for
use in communicating to the lay science community and pub-
lic the importance of mass Spectrometry to environmental
protection — its key and unique role in ultimately protecting
public health and minimizing risks of chemical exposure.
The article is available at: http://WWW.epa.gOV/nerlesdl/
chemistry/pharma/index.htm
Christian Daughton, NERL-Las Vegas, (702) 798-2207
NEKL Task #6980*
EPA Continues RAP with Shaw
The start of a new school year marks the beginning of the
eleventh year of the EPA/Shaw University Research Appren-
ticeship Program (RAP) for High School Students. Currently
30 students, representing 11 of the 14 public high schools in
Wake County, North Carolina, are participating in the RAP.
Students apply for the program in the Spring semester of 8th
grade and continue in the year-round program until they
graduate from high school. Students accepted into the pro-
gram must demonstrate superior ability in math and science;
and applications are evaluated based on grades, teacher rec-
ommendations, and student essays. Acceptance into RAP is
very competitive: in 2001 there were over 100 applicants for
eight positions.
The objective of this program is to encourage students to
pursue advanced degrees in mathematics, science, and engi-
neering. Begun in 1990, the RAP provides students with the
opportunity to interact with scientists and engineers and to
develop effective scientific research and technical skills.
During the academic year, classes, workshops, and monthly
interactive presentations by EPA scientists are given three
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Saturdays each month at Shaw University in Raleigh, North
Carolina. During the summer, rising 9th, 10th, and 11th-grade
students attend six weeks of classes, workshops, and field
trips coordinated by Shaw University; rising seniors appren-
tice under EPA research mentors at our research facilities.
Senior research projects this past year included studies such
as "Low TEWI Alternatives for Supermarket Refrigeration,"
"Quantifying the Activity Patterns of a Dog and Children
Using Video Translation Software," and "The Role of Peroxi-
some Proliferation in the Induction of Hepathocellular Can-
cer by Chloral Hidrate and Trichloroacetic Acid."
This intensive research experi-
ence immerses students in the life
of scientific research and culmi-
nates in a research forum during
which each student presents their
work to an audience that includes
the mentors, other students in the
program, students' parents, and
EPA scientists.
The success of the EPA/Shaw University RAP is irrefut-
able. As of June 2001, fifty-six high school students directly
benefitted through participation in the program. Nine RAP
participants have been accepted into the prestigious North
Carolina School of Science and Mathematics. At least three
students co-authored peer-reviewed journal articles based on
research conducted while working at the EPA; and during the
1999—2000 academic year, participating students were each
enrolled in at least two advanced placement courses in math
and science. Most significantly, 100% of those who partici-
pated in the program entered college — 90% majored in ei-
ther science, math, or engineering with the support of over
half a million dollars in scholarships and grants.
The benefits of EPA's partnership with Shaw University
extend beyond the participating students to the EPA itself.
Mentors are grateful for the high caliber of work and conta-
gious energy brought into their labs by RAP students. Re-
flecting the universal satisfaction with the program, EPA
scientists have successfully recruited two program graduates
to work as EPA full-time summer employees. Beyond these
internal benefits, RAP participants serve as positive spokes-
persons for the EPA and undoubtedly contribute to the EPA
mission of protecting human health and safeguarding the
natural environment.
Kelly Uovic, NERL-RTP, (919) 541-7717
European Connection
Dr. Andrew Lindstrom was an invited platform speaker
representing the NERL at the recent NATO Advanced Study
Institute conference, "Disease Markers in Exhaled Breath:
Basic Mechanisms and Clinical Applications," held this sum-
mer in Crete, Greece. Dr. Lindstrom's presentation "Alveolar
Breath Sampling and Analysis in Human Exposure Assess-
ment Studies" will be published as a chapter in the NATO
monograph produced for this meeting. Due to his excellent
presentation, Dr. Lindstrom has been invited to participate in
the European Respiratory Society Task Force on Exhaled
Biomarkers. The task force will meet next in Berlin, Ger-
many.
Sharing Expertise in Okinawa
Mr. Joachim Pleil, NERL Human Exposure and Atmo-
spheric Sciences Division, was invited to Okinawa, Japan by
the U.S. Marine Corps to present a series of lectures on envi-
ronmental sampling and analysis to American and Japanese
professionals dealing with environmental, occupational health
and safety, hazardous waste, and public health concerns at the
various American installations. This activity, paid for and
organized by the Marine Corps Environmental Training Insti-
tute, was for all services including the Navy, Air Force, and
the U.S. Military Hospital. Pleil also advised senior military
staff on local environmental monitoring issues. Pleil is an
expert in the methods development area dealing with
biomarkers of exposure.
Please send your comments, feedback, or items for inclusion in the next edition to:
Robin Baily (baily.robin@epa.gov)
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