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Human Exposure and Atmospheric Sciences Division Publications: 2006

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This page lists publication titles, citations and abstracts produced by NERL's Human Exposure and Atmospheric Sciences Division for the year 2006, organized by Publication Type. Your search has returned 134 Matching Entries.

See also Human Exposure and Atmospheric Sciences Division citations with abstracts: 1999,  2000,  2001,  2002,  2003,  2004,  2005,  2006,  2007,  2008,  2009

Technical Information Manager: Liz Hope - (919) 541-2785 or hope.elizabeth@epa.gov

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Presented/Published
BOOK CHAPTER Integrating Bioanalytical Capability in An Environmental Analytical Laboratory 12/19/2006
VAN EMON, J. M., J. C. CHUANG, R. M. TREJO, AND J. DURNFORD. Integrating Bioanalytical Capability in An Environmental Analytical Laboratory. Chapter 1, Immunoassays and other Bioanalytical Techniques. CRC Press - Taylor & Francis Group, LLC, Boca Raton, FL, 1-44, (2006).
Abstract: The product is a book chapter which is an introductory and summary chapter for the reference work "Immunoassays and Other Bianalytical Techniques" to be published by CRC Press, Taylor and Francis Books. The chapter provides analytical chemists information on new techniques and gives examples on how to integrate bioanalytical methods in to an environmental analytical laboratory.

ETV DOCUMENT An Environmental Technology Verification (Etv) Testing of Enzymatic Test Kits for Warfare Agents and Pesticides in Drinking Water 11/01/2006
BATTELLE MEMORIAL INSTITUTE, R. MANGARAJ, S. BUEHLER, A. DINDAL, Z. WILLENBURG, AND K. RIGGS. An Environmental Technology Verification (Etv) Testing of Enzymatic Test Kits for Warfare Agents and Pesticides in Drinking Water. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-06/118 (NTIS PB2007-100691), 2006.
Abstract: Enzymatic test kits, generally designed to be handheld and portable, detect the presence of chemical agents, carbamate pesticides, and/or organophosphate pesticides by relying on the reaction of the cholinesterase enzyme. Under normal conditions, the enzyme reacts as expected with other chemicals present in the test kit. The activity of the enzyme is inhibited, however, by chemical agents, carbamate pesticides, and organophosphate pesticides. The effects of this inhibition will then generally lead to a color change, indicating the presence or absence of these compounds.

ETV DOCUMENT An Environmental Technology Verification (Etv) Testing of a Tracedetect's Safeguard Metals Analyzer for Arsenic 09/20/2006
BATTELLE MEMORIAL INSTITUTE, A. GREGG, T. KELLY, Z. WILLENBURG, A. DINDAL, AND K. RIGGS. An Environmental Technology Verification (Etv) Testing of a Tracedetect's Safeguard Metals Analyzer for Arsenic. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-06/098 (NTIS PB2006-115764), 2006.
Abstract: The TraceDetect's SafeGuard is designed to automatically measure total arsenic concentrations in drinking water samples (including raw water and treated water) over a range from 1 ppb to over 100 ppb. Once the operator has introduced the sample vial and selected "measure" on the control computer, all calibrations, dilutions, reductions, standard additions, and measurements are automatically performed by the SafeGuard with the results displayed and logged in a data file. The SafeGuard consists of three main components: the expert system, the fluidics system, and TraceDetect's patented NanoBand - sensor and potentiostat. Each of these components has a part in the measurement process from controlling the pumps, to adding chemicals, to making measurements and interpreting the results, minimizing the effort and expertise required to make trace metal measurements of this type with high precision. The SafeGuard uses anodic stripping voltammetry (ASV) and the method of standard addition to make metals measurements. The ASV is an electro-analytical method that detects ions in a solution by the potential at which they oxidize and strip away from the surface of an electrode. The SafeGuard is able to measure As (III) and reduce As (V) to As (III) to measure total arsenic. The SafeGuard automatically stores data for every measurement and operation.

ETV DOCUMENT An Environmental Technology Verification (Etv) Testing of Seven Technologies Detecting Toxicity in Drinking Water (R2) 08/22/2006
BATTELLE MEMORIAL INSTITUTE, M. SCHROCK, R. JAMES, A. DINDAL, Z. WILLENBERG, AND K. RIGGS. An Environmental Technology Verification (Etv) Testing of Seven Technologies Detecting Toxicity in Drinking Water (R2). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-06/081 (NTIS PB2006-114709), 2006.
Abstract: Rapid toxicity technologies can detect certain toxins and with testing it can be determined their susceptibility to interfering chemical in controlled experimental matrix. Rapid toxicity technologies do not identify or determine the concentrations of specific contaminants, but serve as a screening tool to quickly determine whether the water is potentially toxic. The technologies in this case were tested for their ability to detect such contaminants as: industrial chemicals, pesticides, rodenticides, pharmaceuticals, nerve agents and biological toxins.

ETV DOCUMENT An Environmental Technology Verification (Etv) Testing of Four Dioxin Emission Monitoring Systems 08/17/2006
BATTELLE MEMORIAL INSTITUTE, K. COWEN, T. KELLY, A. DINDAL, Z. WILLENBERG, AND K. RIGGS. An Environmental Technology Verification (Etv) Testing of Four Dioxin Emission Monitoring Systems. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-06/079 (NTIS PB2006-114705), 2006.
Abstract: The Environmental Technology Verification (ETV) Program, beginning as an initiative of the U.S. Environmental Protection Agency (EPA) in 1995, verifies the performance of commercially available, innovative technologies that can be used to measure environmental quality. The ETV provides, through a third-party, quality-assured performance data so buyers and users of environmental technologies can make informed purchase and application decisions, thus providing one path to reducing emissions and improving human health. To provide cost-effective testing, Stakeholder committees, made up of members with diverse backgrounds, provide guidance to the ETV by identifying and prioritizing environmental technologies to address present day environmental quality challenges.
The ETV Advanced Monitoring Systems (AMS) Center, one of six ETV Centers, is actively involved in verifying the performance of advanced monitoring systems available to the public for purchase. The AMS Center participates in the mission of the ETV by providing test plans, protocols, conducting independent performance tests of technologies, and preparing verification reports and statements describing the results of the testing. Vendors of tested technologies can use the verification reports and statements for marketing purposes. All approved verification reports are posted on the ETV Web Site as a form of distribution. The individual verification reports and statements describe by this abstract are for four Dioxin Emission Monitoring Systems: BM Becker Messtechnik GmbH's AMESA, IDX Technologies LTD's RIMMPA-TOFMS, Monitoring Systems GmbH's DioxinMonitoringSystem and SRI International/EPA's Jet-REMPI.

The EPA Method 23 s the certified extractive method used for quantifying polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) emissions from incinerators in the United States as well as in many other countries. This method is labor-intensive, expensive, and requires an extended time for subsequent laboratory analysis of collected samples. As a result, Method 23 measurements are made infrequently only for compliance purposes and not for long- or short-term performance monitoring. Emerging technologies are being developed to provide semi-continuous monitoring or long-term sampling of PCDD/PCDFs and may have the potential to provide more information on PCDD/PCDF source emissions than the relatively few samples required under federal or state regulations. For example, in Europe, mainly in Belgium and Germany, long-term sampling of PCDD/PCDFs has been used for compliance measurements since 2000. However, the performance of these newly introduced technologies has not been evaluated in the United States to determine their relative operational capabilities.

The purpose of this verification test was to generate performance data on four dioxin emission monitoring systems. The test was conducted at EPA's Research Triangle Park (RTP), North Carolina, campus over a period of two weeks in September 2005 and was supported by ARCADIS under a subcontract from Battelle. The accuracy and range of the technologies were determined through comparisons to a modified version of Method 23 for the integrated sampling of PCDD/PCDF with modifications as described in Section 3.2.2 of the reports. Other performance parameters such as data completeness and operational factors were determined from operator observations.

The verification test was conducted according to procedures specified in the Test/QA Plan for Verification of Dioxin Emission Monitoring Systems and the Quality Management Plan for the ETV/AMS Center as described in the reports, the performance of the technologies were evaluated in terms of: relative accuracy, range, data completeness, and operational factors (ease of use, maintenance, and consumables/waste generated). QA oversight of verification testing was provided by Battelle and EPA. Battelle QA staff conducted a technical systems audit (TSA), a performance evaluation audit, and a data quality audit of 10% of the test data. The EPA AMS Center QA Manager also conducted a TSA.

The verification statements, the full reports on which they are based, and the test/QA plan for this verification test are all available at www.epa.gov/etv/centers/center1.html .

ETV DOCUMENT Environmental Technology Verification Report: Constellation Technology Corporation Ct-1128 Portable Gas Chromatograph-Mass Spectrometer 07/25/2006
BATTELLE MEMORIAL INSTITUTE, R. MANGARAJ, A. DINDAL, Z. WILLENBERG, AND K. RIGGS. Environmental Technology Verification Report: Constellation Technology Corporation Ct-1128 Portable Gas Chromatograph-Mass Spectrometer. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-06/071 (NTIS PB2006-113524), 2006.
Abstract: The Environmental Technology Verification (ETV) Program, beginning as an initiative of the U.S. Environmental Protection Agency (EPA) in 1995, verifies the performance of commercially available, innovative technologies that can be used to measure environmental quality. The ETV provides, through a third-party, quality-assured performance data so buyers and users of environmental technologies can make informed purchase and application decisions, thus providing one path to reducing emissions and improving human health. To provide cost-effective testing, Stakeholder committees, made up of members with diverse backgrounds, provide guidance to the ETV by identifying and prioritizing environmental technologies to address present day environmental quality challenges.
The ETV Advanced Monitoring Systems (AMS) Center, one of six ETV Centers, is actively involved in verifying the performance of advanced monitoring systems available to the public for purchase. The AMS Center participates in the mission of the ETV by providing Test Plans, Protocols, conducting independent performance tests of technologies, and preparing Verification Reports and Statements describing the results of the testing. Vendors of tested technologies can use the Verification Reports and Statements for marketing purposes. All approved Verification Reports are posted on the ETV Web Site as a form of distribution. The individual verification report and statement describe by this abstract is for a Constellation Technology Corp. CT-1128 Portable GC/MS.

Many volatile and semivolatile contaminants in water are detected using bench-top mass spectrometers in a traditional laboratory setting. However, the CT-1128 verified in this test was a portable unit designed to be taken outside the laboratory setting for field analysis. This portability offers an advantage to first-responders and other users who need chemical information when time, sampling, and other limitations preclude analysis in a laboratory.

The ability of the CT-1128 to identify and quantify target contaminants was tested in various water matrices. The CT-1128 was evaluated for the following performance parameters: accuracy, precision, linearity. sensitivity, instrument stability, potential matrix and interference effects, field portability, and operational factors. Three classes of contaminants were used for testing: volatile organic compounds (benzene, toluene, ethyl benzene, total xylene), pesticides (2,4-D and dicrotophos), and chemical warfare agents (VX, GB, and GD). The contaminants were selected based on recommendations from the AMS Center stakeholders. The target contaminant concentrations were constructed to bracket the concentrations of interest, which were calculated using LD50 values assuming a 70-kilogram individual consuming 250 milliliters (mL) of the contaminated water. When LD50 data were not available or feasible for testing, the maximum contamination level, as defined by EPA National Primary Drinking Water Regulations, were used. Reference measurements were conducted on performance test samples only, to confirm the accuracy of sample preparation.



In addition to the performance test, drinking water, buffered waters, and trihalomethanes-fortified water samples, blanks and unfortified matrix samples were analyzed to confirm negative responses in the absence of target contaminants and also to ensure that no sources of contamination were introduced during the analysis.

Experienced GC-MS operators were used for testing since the vendor suggests that a new user obtain training in the use of a GC-MS prior to operating the CT-1128. The vendor identified solid phase microextraction (SPME) as the technique for preparing the water samples for subsequent GC-MS analysis by the CT-1128. It is very important to note that the methodology provided by the vendor was not optimized for any one specific target chemical. The same SPME fiber type and GC column were used throughout the test for all analytes.

QA oversight of verification testing was provided by Battelle and EPA. Battelle QA staff conducted a technical systems audit, a performance evaluation audit, and a data quality audit of 10% of the test data.

This verification statement, the full report on which it is based, and the test/QA plan for this verification test are all available at www.epa.gov/etv/centers/center1.html .


EXTRAMURAL DOCUMENT Optimization of Thermal Optical Analysis for the Measurement of Black Carbon in Regional Pm2.5: A Chemometric Approach 10/12/2006
CONNY, J. M. Optimization of Thermal Optical Analysis for the Measurement of Black Carbon in Regional Pm2.5: A Chemometric Approach. National Institute of Standards and Technology (NIST), Gaithersburg, MD, 2006.
Abstract: Thermal-optical analysis (TOA) is the principal method of the U.S. EPA's National Air Monitoring System for determining refractory carbon from combustion, or elemental carbon (EC), in particulate matter <2.5 µm (PM2.5). To isolate and quantify EC from organic carbon (OC) in PM, TOA combines a thermal protocol for removing carbonaceous material on a particle-laden quartz fiber filter with a system to optically monitor the filter during heating. The optical nature of TOA, in particular the thermal-optical transmission method (TOT), necessarily implies that what is measured is the mass of the light-absorbing component of EC, i.e., black carbon (BC). In 2003 the National Institute of Standards and Technology and the U.S. Environmental Protection Agency entered an agreement to optimize the TOA thermal protocol for PM2.5 based on an understanding of TOA's optical behavior, and thus, for measuring BC in PM2.5. While historically TOA has been used in studies concerned with the effect of PM on health and visibility, TOT is potentially a powerful method for measuring light-absorbing aerosol mass from combustion that is responsible for positive aerosol radiative forcing in global climate change [1]. Unfortunately, TOA is problematic in that different thermal protocols produce different BC results on the same sample material, and no protocol has been shown to produce BC measurements with proven accuracy and comparability with other methods. The principal focus of this research is the TOT method as implemented on Sunset Laboratory's Dual-Optics Carbon Analyzer. Since this instrument measures BC by the thermal-optical reflection method (TOR) along with TOT, an investigation of the reflection method was possible. A summary of the research on the TOA optimization is presented here.

JOURNAL On Statistical Issues Related to Farmworker Studies (9418let) 12/01/2006
BARR, D. B., D. LANDSITTEL, M. NISHIOKA, K. W. THOMAS, B. CURWIN, J. H. RAYMER, K. C. DONNELLY, L. MCCAULEY, AND P. B. RYAN. On Statistical Issues Related to Farmworker Studies (9418let). ENVIRONMENTAL HEALTH PERSPECTIVES. National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, NC, 114(12):A688-A689, (2006).
Abstract: This product is a response to a letter to the editor regarding an Environmental Health Perspective research article titled: "A Survey of Laboratory and Statistical Issues Related to Farmworker Exposure Studies".

JOURNAL Development and Evaluation of a High-Volume Dichotomous Sampler for Chemical Speciation of Coarse and Fine Particles 11/01/2006
SARDAR, S. B., M. GELLER, C. SIOUTAS, AND P. A. SOLOMON. Development and Evaluation of a High-Volume Dichotomous Sampler for Chemical Speciation of Coarse and Fine Particles. JOURNAL OF AEROSOL SCIENCE. Elsevier Science Ltd, New York, NY, 37(11):1455-1465, (2006).
Abstract: This paper describes the development and field evaluation of a compact high-volume dichotomous sampler (HVDS) that collects coarse (PM10-2.5) and fine (PM2.5) particulate matter. In its primary configuration as tested, the sampler size-fractionates PM10 into coarse and fine fractions with a minor flow ratio of 10% (minor/total flow rate), with major and minor flow rates of 900 and 100 l min-1, respectively. Performance evaluation for concentration enrichment was conducted with a 4% minor flow ratio (40 l min-1 minor flow) as well. Tests demonstrated near ideal results at both 10% and 4% minor flow ratios, indicating enrichment to be independent of minor flow rates within the range evaluated. Reasonable agreement was found between the new sampler and collocated Partisol and MOUDI for ambient measurements. Investigation of the effect of different ambient parameters like RH and wind speed on coarse PM concentration corroborates results from earlier studies. The HVDS is an effective system to collect coarse and fine PM simultaneously, allowing for comprehensive standard chemical analyses over short sampling intervals.

JOURNAL The Use of Biomonitoring Data in Exposure and Human Health Risk 11/01/2006
ALBERTINI, R., M. BIRD, N. DOERRER, L. L. NEEDHAM, S. ROBISON, L. S. SHELDON, AND H. ZENICK. The Use of Biomonitoring Data in Exposure and Human Health Risk. ENVIRONMENTAL HEALTH PERSPECTIVES. National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, NC, 114(11):1755-1762, (2006).
Abstract: Biomonitoring utilizes analytical methods which permit the accurate measurement of low levels of environmental chemicals in human tissues. However, depending on the intended use, biomonitoring, like all exposure tools, may not be a stand-alone exposure assessment tool for some of its environmental public health uses. While biomonitoring data demonstrate that many environmental chemicals are absorbed in human tissues, uncertainty exists regarding if and at what concentrations many of these chemicals cause adverse health outcomes. Moreover, without exposure pathway information, it is difficult to relate biomonitoring results to sources and routes of exposure and develop effective health risk management strategies. Based on the workshop and follow-up discussions, this overview paper summarizes "lessons learned," identifies data gaps, outlines research needs, and offers guidance for designing and conducting biomonitoring studies, as well as interpreting biomonitoring data in the context of risk assessment and risk management.

JOURNAL Impact of Polycyclic Aromatic Hydrocarbons of the Electrochemical Responses of a Ferricynide Probe at Template-Modified Self Assembled Monolayers on Gold Electrodes 11/01/2006
LUO, N., D. W. HATCHETT, AND K. R. ROGERS. Impact of Polycyclic Aromatic Hydrocarbons of the Electrochemical Responses of a Ferricynide Probe at Template-Modified Self Assembled Monolayers on Gold Electrodes. ELECTROANALYSIS. John Wiley & Sons, Ltd., Indianapolis, IN, 18(22):2180-2187, (2006).
Abstract: The impact of pyrene on the electrochemical response of the ferricyanide probe using Self Assembled Monolayer (SAM)-modified gold electrodes was investigated using Cyclic Voltammetry (CV) and Square Wave Voltammetry (SWV). These results suggest the feasibility of using SAMs, particularly the crosslinked (3-mercaptopropyl) trimethoxysilane (MPTS)-SAMs, as a strategy for development of electrochemical sensing of molecularly imprinted SAMs.

JOURNAL A Semiparametric Bayesian Model for Circular-Linear Regression 10/31/2006
GEORGE, B. J. AND K. GHOSH. A Semiparametric Bayesian Model for Circular-Linear Regression. Communications in Statistics - Simulation and Computation. Taylor & Francis, Inc., Philadelphia, PA, 35(4):911-923, (2006).
Abstract: We present a Bayesian approach to regress a circular variable on a linear predictor. The regression coefficients are assumed to have a nonparametric distribution with a Dirichlet process prior. The semiparametric Bayesian approach gives added flexibility to the model and is useful especially when the likelihood surface is ill-behaved. Markov chain Monte Carlo techniques are used to fit the proposed model and generate predictions. The method is illustrated using an environmental data set.

JOURNAL Development of a Physiologically Based Pharmacokinetic Model for Deltamethrin in the Adult Male Sprague-Dawley Rat 10/01/2006
MIRFAZAELIAN, A., K. KIM, S. S. ANAND, H. J. KIM, R. TORNERO-VELEZ, J. V. BRUCKNER, AND J. W. FISHER. Development of a Physiologically Based Pharmacokinetic Model for Deltamethrin in the Adult Male Sprague-Dawley Rat. TOXICOLOGICAL SCIENCES. Society of Toxicology, 93(2):432-442, (2006).
Abstract: Deltamethrin (DLT) is a Type II pyrethroid insecticide widely used in agriculture and public health. DLT is a potent neurotoxin that is primarily cleared from the body by metabolism. To better understand the dosimetry of DLT in the central nervous system, a physiologically based pharmacokinetic (PBPK) model for DLT was constructed for the adult, male Sprague-Dawley (SD) rat that employed both flow-limited (brain, GI tract, liver and rapid-perfused tissues) and diffusion limited (fat, blood/plasma and slowly-perfused tissues) rate equations.

JOURNAL Sources of Mercury Wet Deposition in Eastern Ohio, USA 10/01/2006
KEELER, G. J., M. S. LANDIS, G. A. NORRIS, E. CHRISTIANSON, AND J. T. DVONCH. Sources of Mercury Wet Deposition in Eastern Ohio, USA. ENVIRONMENTAL SCIENCE & TECHNOLOGY. American Chemical Society, Washington, DC, Vol 40(19):5874-5881, (2006).
Abstract: In the fall of 2002, an enhanced air monitoring site was established in Steubenville, Ohio as part of a multi-year comprehensive mercury monitoring and source apportionment study to investigate the impact of local and regional coal combustion sources on atmospheric mercury deposition in the Ohio River Valley. This study deployed advanced monitoring instrumentation, utilized innovative analytical techniques, and applied state-of-the-art statistical receptor models. This paper will present wet deposition data and source apportionment modeling results from daily event precipitation samples collected during the calendar years 2003-2004. The volume-weighted mean mercury concentrations for 2003 and 2004 were 14.0 and 13.5 ng L-1, and total annual mercury wet deposition was 13.5 and 19.7 µg m-2, respectively. Two new EPA implemented multivariate statistical models, Positive Matrix Factorization (PMF) and Unmix, were applied to the data set and six sources were identified. The dominant contributor to the mercury wet deposition was found by both models to be coal combustion (~70%). Meteorological analysis also indicates that a majority of the mercury deposition found at the Steubenville site was due to local and regional sources.

JOURNAL Preface of Special Issue of Aerosol Science and Technology for Particulate Matter Supersites Program and Related Studies 10/01/2006
GELLER, M. AND P. A. SOLOMON. Preface of Special Issue of Aerosol Science and Technology for Particulate Matter Supersites Program and Related Studies. AEROSOL SCIENCE AND TECHNOLOGY. Taylor & Francis, Inc., Philadelphia, PA, 40(10):735-736, (2006).
Abstract: This article is the preface or editors note to a dedicated issue of Aerosol Science and Technology, journal of the American Association for Aerosol Research. It includes a selection of scientific papers from the specialty conference entitled, "Particulate Matter Supersites Program and Related Studies," that was held in February 2005 in Atlanta, Georgia, USA. The American Association of Aerosol Research (AAAR) was the societal sponsor and EPA was a major co-sponsor. Seventeen peer-reviewed papers are included in the special issue covering the following four categories: instrument development and evaluation, measurement methods, pm characterization, and modeling and source apportionment.

JOURNAL Pesticide Measurements from the First National Environmental Health Survey of Child Care Centers Using a Multi-Residue Gc/MS Analysis Method 09/06/2006
TULVE, N. S., P. A. JONES, M. G. NISHIOKA, R. C. FORTMANN, C. W. CROGHAN, J. ZHOU, A. FRASER, C. CAVE, AND W. FRIEDMAN. Pesticide Measurements from the First National Environmental Health Survey of Child Care Centers Using a Multi-Residue Gc/MS Analysis Method. ENVIRONMENTAL SCIENCE & TECHNOLOGY. American Chemical Society, Washington, DC, 40(20):6269-6274, (2006).
Abstract: The US Department of Housing and Urban Development, in collaboration with the US Consumer Product Safety Commission and the US Environmental Protection Agency, characterized the environments of young children (<6 years) by measuring lead, allergens, and pesticides in a randomly-selected nationally representative sample of licensed institutional child care centers. Multi-stage sampling with clustering was used to select 168 child care centers in 30 primary sampling units in the US. Centers were recruited into the study by telephone interviewers. Samples for pesticides, lead, and allergens were collected at multiple locations in each center by field technicians. Field sampling was conducted from July through October, 2001. Wipe samples from indoor surfaces (floors, tabletops, desks) and soil samples were collected at the centers and analyzed using a multi-residue GC/MS analysis method. Based on the questionnaire responses, pyrethroids were the most commonly used pesticides among centers applying pesticides. Among the 63% of centers reporting pesticide applications, the number of pesticides used in each center ranged from 1 to 10 and the frequency of use ranged from 1 to 107 times annually. Numerous organophosphate and pyrethroid pesticides were detected in the indoor floor wipe samples. Chlorpyrifos (0.004-28 ng/cm2), diazinon (0.002-18 ng/cm2), cispermethrin (0.004-3 ng/cm2), and trans-permethrin (0.004-7 ng/cm2) were detected in >67% of the centers. Associations exist between residues measured on the floor and other surfaces for several pesticides (p-values range from <0.0001 to 0.002), but to a lesser degree between floor and soil and other surfaces and soil. Regional analyses indicate no differences in mean level of pesticide loading between the four Census regions (0.08 < p < 0.88). Results show that there is the potential for exposure to pesticides in child care centers.

JOURNAL Special Issue of Atmospheric Environment for Particulate Matter Supersites Program and Related Studies 09/01/2006
WITTIG, A. E. AND P. A. SOLOMON. Special Issue of Atmospheric Environment for Particulate Matter Supersites Program and Related Studies. ATMOSPHERIC ENVIRONMENT. Elsevier Science Ltd, New York, NY, 40(Supplement 2):179-181, (2006).
Abstract: This special issue of Atmospheric Environment provides a selection of papers that were presented at the 2005 AAAR PM Supersites Program and Related Studies International Specialty Conference held in Atlanta, GA, 7-11 February 2005. Topics of papers in this issue range from the evaluation of new methods to measure fine particles and their precursors, to analysis of ambient measurements and modeling results to learn about the sources and fate of aerosols and related species, to health and welfare effects of PM. This special section complements three other special journal issues for the conference in Aerosol Science and Technology, J. Air and Waste Management Association, and Journal of Geophysical Research - Atmospheres, all scheduled to be published in spring 2006.

JOURNAL Establishing a National Environmental Public Health Tracking Network 09/01/2006
MEYER, P., T. H. WATKINS, AND J. QUALTERS. Establishing a National Environmental Public Health Tracking Network. EM: AIR AND WASTE MANAGEMENT ASSOCIATIONS MAGAZINE FOR ENVIRONMENTAL MANAGERS. Air & Waste Management Association, Pittsburgh, PA, 22-24, (2006).
Abstract: This paper describes the CDC's efforts to develop a National Environmental Public Health Tracking Network Tracking Network) with particular focus on air related issues and collaboration with EPA. A Tracking Network is needed in the United States to improve the health of communities by improving access to health and environmental information. The concept originated with a Pew Environmental Health Commission Report that described multiple fragmented health tracking and environmental monitoring systems throughout the US. The different health and environmental data systems were rarely examined together as part of ongoing public health tracking for prevention and control of environmentally related diseases. In responding to these findings, Congress appropriated funds to the Centers for Disease Control and Prevention¿s (CDC's) National Center for Environmental Health (NCEH) to establish a Tracking Network. EPA and CDC initiated collaboration on air quality issues as part of early efforts to develop the Tracking Network.

JOURNAL Strategic Biomonitoring Initiatives: Moving the Science Forward 09/01/2006
ANGERER, J., M. G. BIRD, T. A. BURKE, N. G. DOERRER, L. L. NEEDHAM, S. H. ROBISON, L. S. SHELDON, AND H. ZENICK. Strategic Biomonitoring Initiatives: Moving the Science Forward. TOXICOLOGICAL SCIENCES. Society of Toxicology, 93(1):3-10, (2006).
Abstract: Biomonitoring programs in the United States and Europe demonstrate the vast array of data that are publicly available for the evaluation of exposure trends, identification of susceptible populations, detection of emerging chemical risks, the conduct of epidemiology studies, and evaluation or risk reduction strategies.

JOURNAL Absence of 14 C in PM 2.5 Emissions from Gasohol Combustion in Small Engines 09/01/2006
LEWIS, C. W., J. VOLCKENS, J. N. BRADDOCK, W. S. CREWS, W. A. LONNEMAN, AND A. P. MCNICHOL. Absence of 14 C in PM 2.5 Emissions from Gasohol Combustion in Small Engines. AEROSOL SCIENCE AND TECHNOLOGY. Taylor & Francis, Inc., Philadelphia, PA, 40(9):657-663, (2006).
Abstract: PM2.5 combustion emissions from small engines using ethanol-containing gasoline (gasohol) were analyzed for their 14C content, which was found to be much smaller than in the fuel. This suggests that using 14C measurements on ambient aerosol to estimate the contribution from fossil fuel combustion will be little affected by increased use of gasohol.

JOURNAL ELISA and Sol-Gel Based Immunoaffinity Purification of the Pyrethroid Bioallethrin in Food and Environmental Samples 08/10/2006
KAWARE, M., A. BRONSHTEIN, J. SAFI, J. M. VAN EMON, J. C. CHUANG, B. HOCK, K. KRAMER, AND M. ALTSTEIN. ELISA and Sol-Gel Based Immunoaffinity Purification of the Pyrethroid Bioallethrin in Food and Environmental Samples. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY. American Chemical Society, Washington, DC, 54:6482-6492, (2006).
Abstract: The peer-reviewed article describes the development of a new sol-gel based immunoaffinity purification procedure and an immunoassay for the pyrethroid bioallethrin. The immunoaffinity chromatography procedure was applied to food samples providing an efficient cleanup prior to immunoassay or gas chromatography-mass spectrometry (GC-MS) detection. The immunoaffinity column removed interfering components in the acetone extracts of the food samples as detected by GC-MS and yielded high recovery of bioallethrin from spiked extracts. Environmental soil and dust samples could be analyzed by an enzyme-linked immunosorbent assay (ELISA) without a cleanup step.

JOURNAL Children's Residential Exposure to Chlorpyrifos: Application of Cppaes Field Measurements of Chlorpyrifos and Tcpy Within Mentor/Sheds Pesticides Model 08/01/2006
HORE, P., V. ZARTARIAN, J. XUE, H. A. OZKAYNAK, S. WANG, Y. YANG, P. CHU, L. S. SHELDON, M. ROBSON, L. L. NEEDHAM, D. B. BARR, N. C. FREEMAN, P. G. GEORGOPOULOS, AND P. J. LIOY. Children's Residential Exposure to Chlorpyrifos: Application of Cppaes Field Measurements of Chlorpyrifos and Tcpy Within Mentor/Sheds Pesticides Model. SCIENCE OF THE TOTAL ENVIRONMENT. Elsevier Science Ltd, New York, NY, 366(1-2):525-537, (2005).
Abstract: The comprehensive individual field-measurements on non-dietary exposure collected in the Children's-Post-Pesticide-Application-Exposure-Study (CPPAES) were used within MENTOR/SHEDS-Pesticides, a physically based stochastic human exposure and dose model. In this application, however, the model was run deterministically. The MENTOR/SHEDS-Pesticides employed the CPPAES as input variables to simulate the exposure and the dose profiles for seven children over a 2-week post-application period
following a routine professional indoor crack-and-crevice chlorpyrifos application. The input variables were obtained from a personal activity diary, microenvironmental measurements and personal biomonitoring data obtained from CPPAES samples collected from the individual children and in their homes. Simulation results were compared with CPPAES field measured values obtained from the childrens' homes to assess the utility of the different microenvironmental data collected in CPPAES, i.e. indicator toys and wipe samplers to estimate aggregate exposures that can be result from one or more exposure pathways and routes. The final analyses of the database involved comparisons of the actual data obtained from the individual biomarker samples of a urinary metabolite of chlorpyrifos (TCPy) and the values predicted by MENTOR-SHEDS Pesticides using the CPPAES-derived variables. Because duplicate diet samples were not part of the CPPAES study design, SHEDS-Pesticides simulated dose profiles did not account for the dietary route. The research provided more confidence in the types of data

that can be used in the inhalation and dermal contact modules of MENTOR/SHEDS-Pesticides to predict the pesticide dose received by a child. It was determined that we still need additional understanding about: 1. the types of activities and durations of activities that result in non-dietary ingestion of pesticides and 2. the influence of dietary exposures on the levels of TCPY found in the urine.

JOURNAL Air Contaminant Exposure During the Operation of Lawn and Garden Equipment 07/01/2006
BALDAUF, R. W., C. FORTUNE, J. P. WEINSTEIN, M. WHEELER, AND F. BLANCHARD. Air Contaminant Exposure During the Operation of Lawn and Garden Equipment. JOURNAL OF EXPOSURE ANALYSIS AND ENVIRONMENTAL EPIDEMIOLOGY. Nature Publishing Group, London, Uk, 16(4):362-370, (2006).
Abstract: The U.S. Environmental Protection Agency (EPA) initiated the Small Engine Exposure Study (SEES) to evaluate potential exposures among users of small, gasoline-powered, non-road spark-ignition (SI) lawn and garden engines. Equipment tested included riding tractors, walk-behind lawn mowers, string trimmers, and chainsaws. Personal and background air quality measurements were collected on equipment operators for carbon monoxide (CO), particulate matter less than 2.5 µm in aerodynamic diameter (PM2.5), volatile organic compounds (VOCs), and aldehydes. PM2.5 measurements included continuous and integrated mass, elemental and organic carbon (EC/OC), and trace metals. Aldehyde measurements included speciation for formaldehyde and acetaldehyde.
The results demonstrated that equipment operators can experience elevated exposures to CO, PM2.5 and air toxics while operating these engines. Ten-second average CO personal exposures spanned over two orders of magnitude, with short-term concentrations exceeding 120 ppm for some engine applications tested. PM2.5 concentrations averaged over each engine test period also spanned two orders of magnitude. The results also suggest that health standards, such as the CO and PM2.5 National Ambient Air Quality Standards (NAAQS), may be exceeded for certain equipment types under certain operating scenarios. Aldehyde measurements suggested exposures from primary engine emissions that exceed typical ambient concentrations, but do not exceed occupational health standards. Continuous exposure measurements illustrated the important role of the operator's activity and environmental conditions in affecting exposure levels.

JOURNAL Secondary Organic Carbon and Aerosol Yields from the Irradiations of Isoprene and Á-Pinene in the Presence of No x and So 2 06/15/2006
KLEINDIENST, T. E., E. O. EDNEY, M. LEWANDOWSKI, J. H. OFFENBERG, AND M. JAOUI. Secondary Organic Carbon and Aerosol Yields from the Irradiations of Isoprene and Á-Pinene in the Presence of No x and So 2. ENVIRONMENTAL SCIENCE & TECHNOLOGY. American Chemical Society, Washington, DC, 40(12):3807-3828, (2006).
Abstract: A laboratory study was carried out to investigate the secondary organic carbon (SOC) yields of a-pinene and isoprene in the presence of SO2, which produces acidic aerosol in the system. Experiments were based on irradiating each hydrocarbon (HC) with NOx in a 14.5 m3 smog chamber operated in the dynamic mode. The experimental design consisted of several multi-part experiments or each HC. In the first part of each experiment, an HC/NOx irradiation was conducted in the absence of SO2 and was followed by irradiations with the addition of SO2 in subsequent parts. Filter-based analyses for organic carbon were made using a thermal-optical approach either with an off-line instrument or in situ with an automated instrument. For isoprene in the absence of SO2, the SOC yield was approximately 0.001, a value consistent with earlier work from this laboratory. With the addition of up to 200 ppb SO2, the yield increased by a factor of 7. For α-pinene in the absence of SO2, the SOC yield of the irradiated mixture was found to average 0.096 from two experiments. With SO2 in the system, the SOC yield increased on average to 0.132. These results suggest that SO2, and by inference acidic aerosol, may play a role in increasing the yield of SOC from the photooxidation products of biogenic hydrocarbons or by the direct uptake of biogenic hydrocarbons onto acidic aerosol.

JOURNAL Analysis of Secondary Organic Aerosol Compounds from the Photooxidation of d-Limonene in the Presence of No X and Their Detection in Ambient PM 2.5 06/15/2006
JAOUI, M., E. CORSE, T. E. KLEINDIENST, J. H. OFFENBERG, M. LEWANDOWSKI, AND E. O. EDNEY. Analysis of Secondary Organic Aerosol Compounds from the Photooxidation of d-Limonene in the Presence of No X and Their Detection in Ambient PM 2.5. ENVIRONMENTAL SCIENCE & TECHNOLOGY. American Chemical Society, Washington, DC, 40(12):3807-3828, (2006).
Abstract: Chemical analysis of secondary organic aerosol (SOA) from the photooxidation of a d-limonene/NOx/air mixture was carried out. SOA, generated in a smog chamber, was collected on Zefluor filters. To determine the structural characteristics of the compounds, the filter samples were solvent extracted and derivatized using analytical techniques that characterize functional groups contained in the compound: BF3-methanol derivatization was used for carboxylic groups, BSTFA for acidic and nonacidic hydroxyl groups, and PFBHA for ketone and aldehyde groups. The resulting derivative compounds were analyzed by GC-MS in the methane CI and EI modes. GC-MS analysis showed the occurrence of 103 oxygenated organic compounds in the filter extracts, 28 of which were identified. The major components include five tracer compounds previously identified from the photooxidation of α-pinene/NOX or β-pinene/NOx systems, C4-C6 linear dicarboxylic acids, ketolimononaldehyde, limonic acid, and ketolimonic acid. Time profiles, yields, and proposed reaction schemes are provided for selected compounds. The laboratory SOA yield was 0.51 at a SOA concentration of 1470 µg m-3. To determine the contributions of SOA products from d-limonene to ambient PM2.5, an analysis was performed for eight ambient PM2.5 samples collected in the southeastern United States in summer 2003. GC-MS analysis showed the occurrence of 21 d-limonene SOA compounds, indicating the impact of d-limonene on the regional aerosol burden. Based on our analysis, two compounds (# 55 and 69), not observed from the photooxidation of α-pinene or β-pinene, are candidate tracers for d-limonene in atmospheric particulate matter.

JOURNAL Use of GIS and Ancillary Variables to Predict Volatile Organic Compound and Nitrogen Dioxide Levels at Unmonitored Locations 06/15/2006
SMITH, L., S. MUKERJEE, M. GONZALES, C. STALLINGS, L. M. NEAS, G. A. NORRIS, AND H. A. OZKAYNAK. Use of GIS and Ancillary Variables to Predict Volatile Organic Compound and Nitrogen Dioxide Levels at Unmonitored Locations. ATMOSPHERIC ENVIRONMENT. Elsevier Science Ltd, New York, NY, 40(20):3773-3787, (2006).
Abstract: This paper presents a GIS-based regression spatial method, known as land-use regression (LUR) modeling, to estimate ambient air pollution exposures used in the EPA El Paso Children's Health Study. Passive measurements of select volatile organic compounds (VOC) and nitrogen dioxide (NO2) were conducted at elementary schools in El Paso, Texas. Predictive equations were developed by regressing passive monitor measurements at the schools with land use variables derived from GIS databases. Rather than using an arbitrary linear LUR model, a multi-step approach was used to develop the predictive equations to provide pollutant predictions at other locations in the city where no pollutant monitoring was done to ultimately assess pollutant impact on children's exposures in schools. The VOC/NO2 predictions provided by this LUR modeling method were linked with the epidemiologic models to assess respiratory health effects from traffic and other urban emissions (not discussed). The LUR model approach used in this study is also being applied in the EPA Detroit Children's Health Study.

JOURNAL Biomonitoring of Exposure in Farmworker Studies 06/01/2006
BARR, D., K. W. THOMAS, B. CURWIN, D. LANDSITTEL, J. H. RAYMER, C. LU, K. C. DONNELLY, AND J. ACQUAVELLA. Biomonitoring of Exposure in Farmworker Studies. ENVIRONMENTAL HEALTH PERSPECTIVES. National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, NC, 114(6):936-942, (2006).
Abstract: Though biomonitoring has been used in many occupational and environmental health and exposure studies, we are only beginning to understand the complexities and uncertainties involved with the biomonitoring process -- from study design, to sample collection, to chemical analysis -- and with interpreting the resulting data. We present an overview of concepts that should be considered when using biomonitoring or biomonitoring data, assess the current status of biomonitoring, and detail potential advancements in the field which may improve our ability to both collect and interpret biomonitoring data. We discuss issues such as the appropriateness of biomonitoring for a given study, the sampling timeframe, temporal variability in biological measurements to nonpersistent chemicals, and the complex issues surrounding data interpretation. In addition, we provide recommendations to improve the utility of biomonitoring in farmworker studies. The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention.
Although this work was reviewed by the U.S. EPA and approved for publication, it may not necessarily reflect official Agency policy.

JOURNAL A Survey of Laboratory and Statistical Issues Related to Farmworker Exposure Studies 06/01/2006
BARR, D. B., D. LANDSITTEL, M. NISHIOKA, K. W. THOMAS, B. CURWIN, J. H. RAYMER, K. C. DONNELLY, L. MCCAULEY, AND B. RYAN. A Survey of Laboratory and Statistical Issues Related to Farmworker Exposure Studies. ENVIRONMENTAL HEALTH PERSPECTIVES. National Institute of Environmental Health Sciences (NIEHS), Research Triangle Park, NC, 114(6):961-968, (2006).
Abstract: Developing internally valid, and perhaps generalizable, farmworker exposure studies is a complex process that involves many statistical and laboratory considerations. Statistics are an integral component of each study beginning with the design stage and continuing to the final data analysis and interpretation. Similarly, data quality plays a significant role in the overall value of the study. Data quality can be derived from several experimental parameters including statistical design of the study and quality of environmental and biological analytical measurements. We discuss statistical and analytic issues that should be addressed in every farmworker study. These issues include study design and sample size determination, analytical methods and quality control and assurance, treatment of missing data or data below the method's limits of detection, and post-hoc analyses of data from multiple studies.

JOURNAL Continuous and Semi-Continuous Methods for PM Mass and Composition 04/01/2006
SOLOMON, P. A. AND C. SIOUTAS. Continuous and Semi-Continuous Methods for PM Mass and Composition. EM: AIR AND WASTE MANAGEMENT ASSOCIATIONS MAGAZINE FOR ENVIRONMENTAL MANAGERS. Air & Waste Management Association, Pittsburgh, PA, 11-17, (2006).
Abstract: This article is a review of the status of continuous and semi-continuous methods for PM mass and composition based on results from EPA's PM Supersites Program and related studies. It summarizes recommendations suggested by Solomon and Sioutas (2006 submitted to the J. Air and Waste Management Association) on the same subject. Methods recommendations are divided into two areas: Research and Routine. Research indicates the method is not yet ready for routine network operations and requires additional operational and diagnostic evaluation before it can be ready for such use. Routing indicates it is ready for use in routine networks, but likely still requires additional evaluation to gain further confidence in the methods results.

JOURNAL Seasonal Abundance of Organic Molecular Markers in Urban Particulate Matter from Philadelphia, Pa 04/01/2006
LI, M., S. R. MCDOW, D. J. TOLLERUD, AND M. A. MAZUREK. Seasonal Abundance of Organic Molecular Markers in Urban Particulate Matter from Philadelphia, Pa. ATMOSPHERIC ENVIRONMENT. Elsevier Science Ltd, New York, NY, 40(13):2260-2273, (2005).
Abstract: Organic molecular markers were measured in airborne particulate matter (PM10) from the City of Philadelphia North Broad Street air quality monitoring site to identify the seasonal abundances of key tracer compounds together with their dominant sources. Daily PM10 samples were collected seasonally in 2000 for 4 two-week periods (January, April, August, and October). Ambient concentrations of individual markers are similar to other reported levels for metropolitan Los Angeles, CA and Atlanta, GA. Seasonal and daily variations of marker compounds are consistent with motor vehicle exhaust, particularly in winter. Summer concentration patterns indicate the importance of secondary organic aerosol to the PM10 ambient mass.

JOURNAL Special Issue of the Journal of the Air & Waste Management Association on the Particulate Matter Supersites Program and Related Studies 04/01/2006
CHOW, J. C. AND P. A. SOLOMON. Special Issue of the Journal of the Air & Waste Management Association on the Particulate Matter Supersites Program and Related Studies. JOURNAL OF AIR AND WASTE MANAGEMENT. Air & Waste Management Association, Pittsburgh, PA, 56(4):369-370, (2006).
Abstract: This article is the preface or editors note to the dedicated issue of the Journal of the Air & Waste Management Association for a selection of scientific papers from the specialty conference entitled, "Particulate Matter Supersites Program and Related Studies," that was held in February 2005 in Atlanta, Georgia, USA. The American Association of Aerosol Science was the societal sponsor. Fifteen peer-reviewed papers are included in the special issue.

JOURNAL A Probabilistic Arsenic Exposure Assessment for Children Who Contact Caa Treated Playsets and Decks: Part 1. Model Methodology, Variability Results, and Model Evaluation 04/01/2006
ZARTARIAN, V., J. XUE, H. A. OZKAYNAK, W. DANG, G. GLEN, L. SMITH, AND C. STALLINGS. A Probabilistic Arsenic Exposure Assessment for Children Who Contact Caa Treated Playsets and Decks: Part 1. Model Methodology, Variability Results, and Model Evaluation. RISK ANALYSIS. Blackwell Publishing, Malden, MA, 26(2):515-531, (2005).
Abstract: Concerns have been raised regarding the safety of young children who may contact arsenic residues while playing on and around chromated copper arsenate (CCA)-treated wood playsets and decks. Although CCA registrants voluntarily canceled the production of treated wood for residential use in 2003, the potential for exposure from existing structures and surrounding soil still poses concerns. The EPA's Office of Research and Development developed and applied the probabilistic Stochastic Human Exposure and Dose Simulation model for wood preservatives (SHEDS-Wood) to estimate children's absorbed dose of arsenic from CCA. Skin contact with, and non-dietary ingestion of, arsenic in soil and wood residues were considered for the population of children in the United States who frequently contact CCA-treated wood playsets and decks. Model analyses were conducted to assess the range in population estimates and the impact of potential mitigation strategies such as the use of sealants and hand washing after play events. The results show predicted central values for lifetime annual average daily dose values for arsenic ranging from 10-6 to 10-5 mg/kg/day, with predicted 95th percentiles on the order of 10-5 mg/kg/day. There were several orders of magnitude between lower and upper percentiles. Residue ingestion via hand-to-mouth contact was determined to be the most significant exposure route for most scenarios. Results of several alternative scenarios were similar to baseline results, except for the scenario with greatly reduced residue concentrations through hypothetical wood sealant applications; in this scenario, exposures were lower, and the soil ingestion route dominated. SHEDS-Wood estimates are typically consistent with, or within the range of, other CCA exposure models.

JOURNAL A PROBABILISTIC ARSENIC EXPOSURE ASSESSMENT FOR CHILDREN WHO CONTACT CHROMATED COPPER ARSENATE ( CAA )-TREATED PLAYSETS AND DECKS: PART 2 SENSITIVITY AND UNCERTAINTY ANALYSIS 04/01/2006
XUE, J., V. ZARTARIAN, H. A. OZKAYNAK, W. DANG, G. GLEN, L. SMITH, AND C. STALLINGS. A PROBABILISTIC ARSENIC EXPOSURE ASSESSMENT FOR CHILDREN WHO CONTACT CHROMATED COPPER ARSENATE ( CAA )-TREATED PLAYSETS AND DECKS: PART 2 SENSITIVITY AND UNCERTAINTY ANALYSIS. RISK ANALYSIS. Blackwell Publishing, Malden, MA, 26(2):533-541, (2005).
Abstract: A probabilistic model (SHEDS-Wood) was developed to examine children's exposure and dose to chromated copper arsenate (CCA)-treated wood, as described in Part 1 of this two part paper. This Part 2 paper discusses sensitivity and uncertainty analyses conducted to assess the key model inputs and areas of needed research for children's exposure to CCA-treated playsets and decks. The following types of analyses were conducted: (1) sensitivity analyses using a percentile scaling approach and multiple stepwise regression; and (2) uncertainty analyses using the bootstrap and 2-stage Monte Carlo techniques. The five most important variables, based on both sensitivity and uncertainty analyses, were: wood surface residue-to-skin transfer efficiency; wood surface residue levels; fraction of hand surface area mouthed per mouthing event; average fraction of non-residential outdoor time a child plays on/around CCA-treated public playsets; and frequency of hand washing. In general, there was a factor of 8 for the 5th and 95th percentiles and a factor of 4 for the 50th percentile in the uncertainty of predicted population dose estimates due to parameter uncertainty. Data were available for most of the key model inputs identified with sensitivity and uncertainty analyses; however, there were few or no data for some key inputs. To evaluate and improve the accuracy of model results, future measurement studies should obtain longitudinal time-activity diary information on children, spatial and temporal measurements of residue and soil concentrations on or near CCA treated playsets and decks, and key exposure factors. Future studies should also address other sources of uncertainty in addition to parameter uncertainty, such as scenario and model uncertainty.

JOURNAL Identification of Sources and Estimation of Emission Profiles from Highly Time-Resolved Pollutant Measurements in Tampa, Fl 03/24/2006
PANCRAS, P., J. M. ONDOV, N. POOR, M. S. LANDIS, AND R. K. STEVENS. Identification of Sources and Estimation of Emission Profiles from Highly Time-Resolved Pollutant Measurements in Tampa, Fl. ATMOSPHERIC ENVIRONMENT. Elsevier Science Ltd, New York, NY, 40(Supplement 2):467-481, (2006).
Abstract: Aerosol slurry samples were collected at 30-min intervals for sequential 1-month periods at each of two sites (Sydney and "Dairy") in the Tampa Bay area during the 2002 Bay Regional Atmospheric Chemistry Experiment using the University of Maryland Semicontinuous Elements in Aerosol Sampler-II (SEAS-II). More than 500 samples, believed to be affected by plumes from local utility and industrial sources were selected for electrothermal atomic absorption spectrophotometric analyses for elemental markers (Al, Fe, Cr, Cu, Mn, Pb, Se, As, Ni, Zn and Cd) based on excursions in SO2 and NOx measurements. Correlation of short-term excursions in metals and SO2, and surface wind directions observed between May 23 and 26th, 2002, revealed the influence of an animal feed supplements production facility (AFS),17 km upwind at a station angle of 81°, for which emissions had not previously been detected by standard monitoring methods. Emission "profiles" for this source were developed, separately, from the time series data and by Positive Matrix Factorization (PMF). In addition, a local dust component was evident in Al and Fe concentration profiles during periods of elevated wind speeds and was resolved by PMF. Similarly, large but brief 1.5-h excursion in Zn (maximum, 403 ng/m3), Cd, and Pb on May 17th, were correlated with winds from the direction of an incinerator (station angle, 250°) 17 km from Sydney. Lastly, large excursions in As concentrations (maximum, 86 ng/m3) observed (May 4th and 5th at Sydney and November 2nd and 3rd at the Dairy) were used to locate previously unrecognized sources, tentatively associated with combustion / production of pressure-treated lumber. Profiles developed directly from the time series data were in the range of those derived from PMF and those for the incinerator, with previously published values.

JOURNAL Effect of Soil Properties on Lead Bioavailability and Toxcity to Earthworms 03/01/2006
BRADHAM, K. D., E. A. DAYTON, N. T. BASTA, J. SCHRODER, M. PAYTON, AND R. LANNO. Effect of Soil Properties on Lead Bioavailability and Toxcity to Earthworms. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, 25(3):769-775, (2006).
Abstract: Soil properties are important factors modifying metal bioavailability to ecological receptors. Twenty-one soils with a wide range of soil properties were amended with a single concentration of Pb (2000 mg/kg) to determine the effects of soil properties on Pb bioavailability and toxicity to earthworms. Earthworm mortality ranged from 0% mortality to 100% acute mortality following exposure to the same total concentration of Pb (2000 mg/kg) in amended field soils. Internal Pb concentrations in earthworms ranged from 28.7 to 782 mg Pb/kg, with a mean of 271 mg Pb/kg. Path analysis was used to partition correlations, in an attempt to discern the relative contribution of each soil property. Path analysis results indicated that pH was the most important soil property affecting earthworm mortality (p < 0.01) and internal Pb (p < 0.05). Soil pH was inversely related to mortality and internal Pb. Soil pH is inversely related to soil solution Pb and Pb bioavailability. The most important soil property modifying reproduction was FEAL. Because FEAL is rich in pH dependent cation exchange sites, several soil properties including pH, FEAL and CEC have a causal effect on Pb adsorption and soluble Pb. Path analysis is useful for assessing contaminated soils with a wide range of soil properties and can assist in site ecological risk assessment and remediation decisions for contaminated sites. Soil properties are important factors modifying metal bioavailability and toxicity and should be considered in the ecological risk assessment of metals in contaminated soils.

JOURNAL Immunoassay Method for the Determination of Pentachlorophenol in Soil and Sediment 03/01/2006
CHUANG, J. C., J. M. VAN EMON, J. K. FINEGOLD, Y. CHOU, AND F. RUBIO. Immunoassay Method for the Determination of Pentachlorophenol in Soil and Sediment. ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY. Springer-Verlag, New York, NY, 76(3):381-388, (2006).
Abstract: The journal article describes the use of a prototype immunoassay method for the determination of pentacholorphenol (PCP) in soil and sediment. PCP was used as a pesticide and wood preservative and is not currently available to the general public. The paper stresses the importance of analyzing this compound, sample preparation techniques, and evaluation of the ELISA method utilizing GC/MS. The method can be used as a qualitative or quantitative tool.

JOURNAL Thermal Properties of Secondary Organic Aerosols 02/15/2006
OFFENBERG, J. H., T. E. KLEINDIENST, MOHAMMAD JAOUI, M. LEWANDOWSKI, AND E. O. EDNEY. Thermal Properties of Secondary Organic Aerosols. GEOPHYSICAL RESEARCH LETTERS. American Geophysical Union, Washington, DC, 33(3):1-4, (2006).
Abstract: Volume concentrations of steady-state secondary organic aerosol (SOA) were measured in several hydrocarbon/NOx irradiation experiments. These measurements were used to estimate the thermal behavior of the particles that may be formed in the atmosphere. These laboratory measurements suggest that the difference in the volume of the SOA due to a change in temperature depends upon the reactant concentrations.

JOURNAL Comparison of 24h Average VOC Monitoring Results for Residential Indoor and Outdoor Air Using Carbopack X-Filled Diffusive Samplers and Active Sampling a Pilot Study 02/15/2006
MCCLENNY, W. A., H. JACUMIN, K. OLIVER, H. DAUGHTREY, AND D. A. WHITAKER. Comparison of 24h Average VOC Monitoring Results for Residential Indoor and Outdoor Air Using Carbopack X-Filled Diffusive Samplers and Active Sampling a Pilot Study. JOURNAL OF ENVIRONMENTAL MONITORING. Royal Society of Chemistry, Cambridge, Uk, 8(2):263-269, (2006).
Abstract: Analytical results obtained by thermal desorption GC/MS for 24h diffusive sampling of 11 volatile organic compounds (VOCs) are compared with results of time-averaged active sampling at a known constant flow rate. Air samples were collected with co-located duplicate diffusive sampling tubes and one passivated canister. A total of eight multiple-component sampling events took place at fixed positions inside and outside three private homes. Subsequently, a known amount of sample air was transferred from the canister to an adsorbent tube for analysis by thermal desorption GC/MS. Results for the 11 most prevalent compounds --Freon 11, 1,3-butadiene, benzene, toluene, tetrachloroethene, ethylbenzene, m,p-xylene, o-xylene, 4-ethyltoluene, 1,3,5-trimethylbenzene, and p-dichlorobenzene--show that the ratio of average study values (diffusive sampling to active sampling) is 0.92 with 0.70 and 1.14 extreme ratios. Absolute percent difference for duplicate samples using diffusive sampling was < 10% for the four most prevalent compounds. Agreement between the two sampling approaches indicates that the prediction of approximately constant diffusive sampling rates based on previous laboratory studies is valid under the field conditions.

PRESENTATION Daily Variation in Organic Composition of Fine Particulate Matter in the Detroit Exposure and Aerosol Research Study 12/11/2006
MCDOW, S. R., J. TURLINGTON, D. A. OLSON, L. STOCKBURGER, R. W. WILLIAMS, AND A. F. VETTE. Daily Variation in Organic Composition of Fine Particulate Matter in the Detroit Exposure and Aerosol Research Study. Presented at American Geophysical Union National Meeting, San Francisco, CA, December 11 - 15, 2006.
Abstract: Organic composition of fine particulate matter (PM2.5) was investigated as a part of the Detroit Exposure and Aerosol Research Study (DEARS). A high volume (113 liters/minute) sampler was used at the Allen Park community air monitoring station to collect PM2.5 for analysis by gas chromatography/mass spectrometry (GCMS). Patterns of individual n-alkane concentrations are consistent with a significant biogenic component of PM2.5. Average concentrations of species emitted primarily by motor vehicles, including hopanes and polycyclic aromatic hydrocarbons, were fairly low, and similar to recent summer measurements in other U.S. locations where motor vehicles appear to be an important PM2.5 source.

PRESENTATION Particulate Organic Source Markers in the New York City Metropolitan Area 12/11/2006
MCDOW, S. R., M. MAZUREK, M. LI, R. M. DUVALL, AND G. A. NORRIS. Particulate Organic Source Markers in the New York City Metropolitan Area. Presented at American Geophysical Union National Meeting, San Fancisco, CA, December 11 - 15, 2006.
Abstract: A sampling network of four sites was established for the Speciation of Organics for Apportionment of PM2.5 (SOAP) project during 2002-2003 to investigate composition, seasonal and spatial variability, and source contributions to particulate organic matter in the New York City metropolitan area. A total of 63 organic species were selected for analysis based on their promise for distinguishing anthropogenic, biogenic, primary, and secondary sources. Results suggested differences in spatial variability for different sources of particulate organic matter within the metropolitan area. For example, hopanes exhibited substantially higher concentrations at urban and near road sites than suburban and background sites, demonstrating a local influence for motor vehicle contributions, but dicarboxylic acids were more spatially uniform, suggesting that secondary organic aerosol was more regional in nature.

PRESENTATION How Can Biomonitoring Inform Exposure Assessment? Permethrin a Case Study. 12/03/2006
MORGAN, M. K. AND L. S. SHELDON. How Can Biomonitoring Inform Exposure Assessment? Permethrin a Case Study. Presented at Society of Risk Analysis Annual Meeting, Baltimore, MD, December 03 - 06, 2006.
Abstract: Biomonitoring is an important tool for understanding the linkages between external chemical exposures, internal doses and potential health outcomes in humans. In recent years, there has been an explosion of available human biomonitoring data from scientists.

PRESENTATION Summary of Emissions Management Strategy Policy Relevant Findings from EPA's PM Supersites Program 11/06/2006
SOLOMON, P. A. AND P. K. HOPKE. Summary of Emissions Management Strategy Policy Relevant Findings from EPA's PM Supersites Program. Presented at 2006 National Air Monitoring Conference, Las Vegas, NV, November 06 - 09, 2006.
Abstract: EPA is developing an integrated synthesis of key scientific and policy-relevant findings from EPA's Particulate Matter Supersites Program. This presentation provides a summary of the program and the integrated synthesis. Since there are many examples of such findings, ranging from methods to better understanding source-receptor relationships and atmospheric processes, a single example illustrative example is chosen. Here the scientific finding - development of a method to continuously measure particle bound water -- is linked to the policy findings -- the ability to close the mass balance of mass measured on the FRM at one hour time intervals within the uncertainty of the measurements. This is the first time this has been achieved.

PRESENTATION METHOD DEVELOPMENT FOR THE DETERMINATION OF PERFLUORINATED ORGANIC COMPOUNDS ( PFCS ) IN SURFACE WATER 11/05/2006
NAKAYAMA, S., A. B. LINDSTROM, M. J. STRYNAR, X. YE, L. HELFANT, AND J. L. VARNS. METHOD DEVELOPMENT FOR THE DETERMINATION OF PERFLUORINATED ORGANIC COMPOUNDS ( PFCS ) IN SURFACE WATER. Presented at Society of Environmental Toxicology and Chemistry (SETAC), Montreal, QC, CANADA, November 05 - 09, 2006.
Abstract: The method for the determination of perfluorinated organic compounds (PFCs) in surface water has been developed and applied to natural water. The method shows an adequate sensitivity, precision and accuracy for ten kinds of target compounds. These PFCs were found in most samples with total concentrations ranging from 1.64 to 942 ng/L.

PRESENTATION Analysis of Fish Homogenates for Perfluorinated Compounds 11/04/2006
STRYNAR, M. J., X. YE, A. B. LINDSTROM, S. NAKAYAMA, L. HELFANT, J. L. VARNS, AND J. M. LAZORCHAK. Analysis of Fish Homogenates for Perfluorinated Compounds. Presented at Society of Environmental Toxicology and Chemistry (SETAC), Montreal, QC, CANADA, November 04 - 09, 2006.
Abstract: Perfluorinated compounds (PFCs) which include PFOS and PFOA are widely distributed in wildlife. Whole fish homogenates were analyzed for PFCs from the upper Mississippi, the Missouri and the Ohio rivers. Methods development, validation data, and preliminary study results will be discussed

PRESENTATION Development, Evaluation and Application of An Automated Event Precipitation Sampler for Network Operation 10/26/2006
KEELER, G. J., E. CHRISTIANSON, J. BARRES, J. T. DVONCH, F. MARSIK, AND M. S. LANDIS. Development, Evaluation and Application of An Automated Event Precipitation Sampler for Network Operation. Presented at Annual NADP Meeting, Norfolk, VA, October 24 - 26, 2006.
Abstract: In 1993, the University of Michigan Air Quality Laboratory (UMAQL) designed a new wet-only precipitation collection system that was utilized in the Lake Michigan Loading Study. The collection system was designed to collect discrete mercury and trace element samples on an event basis. Results showed that with proper preparation and ultra-clean collection techniques, wet-only precipitation collection utilizing the UMAQL modified MIC-B collector can provide virtually contamination-free mercury and trace element samples. Subsequent application of this collector has led to several source-receptor studies that utilized the event precipitation chemistry data to investigate the sources and pathways for atmospheric contaminants entering sensitive ecosystems.

PRESENTATION Spatial and Temporal Variability of Mobile Source Air Toxics in the Detroit Exposure and Aerosol Research Study 10/24/2006
VETTE, A. F., R. W. WILLIAMS, C. W. CROGHAN, AND D. A. WHITAKER. Spatial and Temporal Variability of Mobile Source Air Toxics in the Detroit Exposure and Aerosol Research Study. Presented at CRC Mobile Source Air Toxics Workshop, Phoenix, AZ, October 24 - 25, 2006.
Abstract: Data from the first two years of the Detroit Exposure and Aerosol Research Study (DEARS) were evaluated to determine spatial and temporal characteristics in concentrations of mobile source air toxics (MSATs). Outdoor concentrations of MSATs were significantly higher in samples collected downwind from and in close proximity to roadways. MSATs measured outdoors in urban neighborhood sites were significantly higher than regional concentrations and at a state operated central community monitoring location indicating significant spatial variation in MSAT concentrations throughout the airshed.

PRESENTATION Sources of Mercury Wet Deposition in Steubenville, Ohio 10/24/2006
LANDIS, M. S., G. A. NORRIS, G. J. KEELER, E. M. CHRISTIANSON, J. T. DVONCH, AND J. SLATER. Sources of Mercury Wet Deposition in Steubenville, Ohio. Presented at The Annual National Atmospheric Deposition Program Meeting, Norfolk, VA, October 24 - 26, 2006.
Abstract: This paper will present wet deposition data and source apportionment modeling results from daily event precipitation samples collected during the calendar years 2003-2004.

PRESENTATION Radiocarbon Source Apportionment in a Biofuels Era 10/23/2006
LEWIS, C. W. Radiocarbon Source Apportionment in a Biofuels Era. Presented at 2006 CRC Mobile Source Air Toxics Workshop, Phoenix, AZ, October 23 - 25, 2006.
Abstract: Biofuels (gasohol and biodiesel) introduce radiocarbon into the U.S. mobile source fuel supply where it was previously absent. Initial measurements of radiocarbon in the PM2.5 combustion emissions from engines using gasohol indicate that this may have less effect on radiocarbon source apportionment of PM2.5 than anticipated.

PRESENTATION An in Silico Investigation of the Enantioselective Metabolism Rates of Triazole Fugicides 10/22/2006
CHANG, D., T. L. WHITEHEAD, M. S. OKINO, C. S. MAZUR, J. F. KENNEKE, R. TORNERO-VELEZ, J. C. JOHNSON, AND C. C. DARY. An in Silico Investigation of the Enantioselective Metabolism Rates of Triazole Fugicides. Presented at 14th North American International Society for the Study of Xenobiotics Meeting, Rio Grande, PUERTO RICO, October 22 - 26, 2006.
Abstract: The objective of this work is to use in silico methods such as ab initio quantum and classical force-field methods to explore and develop an understanding for the enantioselective metabolism rates experimentally observed in the triazole fungicide bromuconazole. This directed study is pivotal for the ab initio generation of chemical-specific metabolic parameters necessary in the development of physiologically-based pharmacokinetic models used in human exposure and risk assessment studies.

PRESENTATION Delamination and Xrf Analysis of Nist Lead in Paint Film Standards 10/19/2006
ROGERS, K. R. AND J. ABACHERLI. Delamination and Xrf Analysis of Nist Lead in Paint Film Standards. Presented at Lead Paint Test Kit Workshop, Research Triangle Park, NC, October 19 - 20, 2006.
Abstract: The objectives of this protocol were to remove the laminate coating from lead paint film standards acquired from NIST by means of surface heating. The average XRF value did not change after removal of the polymer coating suggesting that this protocol is satisfactory for rendering the NIST-XRF standard paint films acceptable for use with the chemically-based lead test kits.

PRESENTATION Detection and Quantification of Asymmetric Peaks 10/08/2006
CROGHAN, C. W. AND R. W. WILLIAMS. Detection and Quantification of Asymmetric Peaks. Presented at SouthEast SAS User Group , Atlanta, GA, October 08 - 10, 2006.
Abstract: One of the goals of a recent U.S. Environmental Protection Agency air pollution study was to relate the participants' activities to their exposures to particulate matter (PM) during their routine activities. PM concentration data were collected continuously with a real-time monitor, downloaded daily in CSV format and concatenated using AWK. Human activity diary information was collected via pen and paper and recovered using scannable decoding software (TeleForm). All data were converted into SAS. The asymmetric response peaks of the particulate matter concentrations made systematic detection and analysis of the area under their respective curves problematic. To overcome this problem, a program was written to locate each peak and generate an integrated value for its response area. Data were smoothed using a running average, inflection points were identified relative to the start and stoppage of each peak, and a moving baseline calculated. Incorporation of human activity descriptors allowed for the quantification of human activity pattern influence upon potential exposures to particulate matter under real-world conditions.We will be discussing two elements in this paper. The first discussion point is the conversion of the data from multiple sources into SAS. The data were collected in various methods including paper questionnaires, computer assisted technician interview, and electronic transfer from the monitoring instrument. The second element is the program that was written to locate the peaks in the data.

PRESENTATION Generating Participant Specific Figures Using Sas Graphic Procedures 10/08/2006
CROGHAN, C. W. AND M. K. MORGAN. Generating Participant Specific Figures Using Sas Graphic Procedures. Presented at SouthEast SAS User Group, Atlanta, GA, October 08 - 10, 2006.
Abstract: An important part of our research at the U.S. Environmental Protection Agency (EPA) is to effectively communicate the results from observational studies to the study participants. This can be particularly challenging where participants are from different socio-economic backgrounds. For our present study, we developed a short, descriptive report that was easy to understand by over 250 participants from low-, middle-, and high-income backgrounds. In each report, we present the chemical concentrations that were found at the participant's home compared to all homes in the study. The most effective way we found was to present the participant's study results using colorized figures. We will discuss the complex process that involved using SAS procedures gmap and greplay, and macro coding, to develop the figures for the reports. By creating an automated process, this program was an excellent solution that was creative, time efficient, and less prone to human error than the historical method of manually generating the plots.
In this paper, we will discuss the different SAS programming components (i.e., data step, SAS graph, and macro programming) that were utilized to construct the requested figures. Some knowledge of SAS programming is assumed. We will point out various efficiency elements that were incorporated within the programming. This paper is not intended to be a complete tutorial on the SAS graphics module. Only elements that were specifically used in generating the figures will be discussed. These elements include proc gmap, proc gslide, and proc greplay.

PRESENTATION Source Apportionment of Fine Particles in the U.S. and Associations Between Inflammatory Marker Il-8 09/14/2006
DUVALL, R. M., G. A. NORRIS, J. M. BURKE, J. K. MCGEE, M. I. GILMOUR, AND R. B. DEVLIN. Source Apportionment of Fine Particles in the U.S. and Associations Between Inflammatory Marker Il-8. Presented at International Aerosol Conference (AAAR & ISAM), St. Paul, MN, September 10 - 15, 2006.
Abstract: Associations are well established between particulate matter (PM) and increased human mortality and morbidity. The association between PM sources and inflammatory marker IL-8 was evaluated in this study.

PRESENTATION Particulate Matter Concentrations Measured in a Residential Neighborhood in Brooklyn, New York City During the Traffic-Related Exposure Study (T-Rex) 09/11/2006
CHEN, F., P. PHOUSONGPHOUANG, R. W. BALDAUF, R. W. WIENER, F. DIMMICK, AND M. WHEELER. Particulate Matter Concentrations Measured in a Residential Neighborhood in Brooklyn, New York City During the Traffic-Related Exposure Study (T-Rex). Presented at AAAR 2006 , St Paul, MN, September 11 - 15, 2006.
Abstract: PM10, PM10-2.5, and PM2.5 concentrations has been measured daily in the Sunset Park neighborhood of Brooklyn, NY from April 21 to May 17, 2005. Results showed the average concentrations of PM fractions were higher when measured closet to the major roadway.

PRESENTATION Performance Verification of Continuous Multi-Parameter Water Monitors for Distribution Systems 09/11/2006
JAMES, R., S. ALLGEIER, R. HAUGHT, AND R. G. FUERST. Performance Verification of Continuous Multi-Parameter Water Monitors for Distribution Systems. Presented at American Water Works Association, Washington, DC, September 10 - 12, 2006.
Abstract: The Environmental Technology Verification (ETV) Program's Advanced Monitoring Systems (AMS) Center has been charged by EPA to verify the performance of commercially available monitoring technologies for air, water, soil. Multi-parameter water monitors for distributions systems were verified as a water security technology by the AMS Center in 2004-2005.

PRESENTATION Performance Verification of Water Security Related Technologies 09/11/2006
RYAN, J., S. ALLGEIER, AND R. G. FUERST. Performance Verification of Water Security Related Technologies. Presented at American Water Works Association, Washington, DC, September 10 - 12, 2006.
Abstract: The Environmental Technology Verification (ETV) Program's Advanced Monitoring Systems (AMS) Center has been charged by EPA to verify the performance of commercially available monitoring technologies for air, water, soil. Four categories of water security technologies (most of which are field portable) have been verified by the AMS Center from 2003-2006.

PRESENTATION Evidence of Seed Oils in Fine Particles from the New York Metropolitan Area 09/10/2006
MAZUREK, M. A., M. LI, S. R. MCDOW, AND C. BELISLE. Evidence of Seed Oils in Fine Particles from the New York Metropolitan Area. Presented at International Aerosol Conference (AAAR/ISAM), St. Paul, MN, September 10 - 15, 2006.
Abstract: This abstract describes a poster on the contribution of seed oils used for cooking to organic particulate matter to be presented at the 2006 International Aerosol Conference sponsored by the American Association for Aerosol Research in St. Paul, Minnesota on September 10-15. Samples were collected in New York City as a part of the Speciation of Organics for Apportionment of PM-2.5 (SOAP) project between May of 2002 and May of 2003. Concentration patterns for individual long-chain aliphatic carboxylic acids are unlikely to be from plant or microbial sources, but are more likely due to the use of seed oils in cooking and indicative of cooking as a significant source of particulate organic matter in New York City.

PRESENTATION Rapid Method Development for Bdes in Twelve Diverse Human Exposure Assessment Media Using the Concept of Core Analytical Tools 09/10/2006
THORN, J. R., M. F. MISTA, M. G. NISHIOKA, N. S. TULVE, AND R. C. FORTMANN. Rapid Method Development for Bdes in Twelve Diverse Human Exposure Assessment Media Using the Concept of Core Analytical Tools. Presented at American Chemical Society, San Francisco, CA, September 10 - 14, 2006.
Abstract: For nine different BDEs, a core analytical method and a single instrumental method were developed and validated so that only the extraction method needed to be adapted for each matrix.

PRESENTATION (Aaar) Semi-Continuous Determination of Water-Soluble Particulate Components and Their Gaseous Precursors: Laboratory and Field Evaluation of Instrumentation Based on Wet Wall Denuder and Ion Chromatography Technology 09/10/2006
LONG, R. W., M. S. LANDIS, K. KRONMILLER, B. D. GROVER, D. J. EATOUGH, R. AL-HORR, AND R. K. STEVENS. (Aaar) Semi-Continuous Determination of Water-Soluble Particulate Components and Their Gaseous Precursors: Laboratory and Field Evaluation of Instrumentation Based on Wet Wall Denuder and Ion Chromatography Technology. Presented at International Aerosol Conference (AAAR), St. Paul, MN, September 10 - 15, 2006.
Abstract: Research conducted by EPA at its facility in Research Triangle Park, NC and by EPA, Brigham Young University (BYU), Dionex Corporation and others during field intensive studies in California, Utah and Florida has demonstrated the capability for the semi-continuous determination of water-soluble particulate components (SO42-, NO3-, NO2-, Cl-, and NH4+) and gaseous precursors (SO2, HNO3, HONO, HCl, and NH3) using instrumentation based on wet wall denuder (WWD) and ion chromatography (IC) technology.

PRESENTATION PM 2.5 Organic Speciation Intercomparison Results 09/10/2006
MCDOW, S. R., M. M. SCHANTZ, S. A. WISE, AND J. JUNGERS. PM 2.5 Organic Speciation Intercomparison Results. Presented at International Aerosol Conference (AAAR/ISAM), St. Paul, MN, September 10 - 15, 2006.
Abstract: This abstract describes a poster on results to a laboratory intercomparison of organic aerosol speciation analysis to be presented at the 2006 International Aerosol Conference sponsored by the American Association for Aerosol Research in St. Paul, Minnesota on September 10-15. Three interlaboratory trials were conducted and good agreement was observed in all trials for polycyclic aromatic hydrocarbons (PAH's) and nitro-substituted PAH's. Agreement between laboratories for other organic species, including alkanes, hopanes, and pyrolyzed sugars, was not clearly demonstrated. New standard reference materials were introduced in hopes of obtaining better agreement for these species.

PRESENTATION PERSONAL, RESIDENTIAL AND CENTRAL SITE PM MASS CONCENTRATIONS ASSOCIATED WITH THE DETROIT EXPOSURE AND AEROSOL RESEARCH STUDY ( DEARS ) 09/10/2006
WILLIAMS, R. W., A. F. VETTE, C. W. CROGHAN, C. D. STEVENS, P. A. JONES, J. THORNBURG, AND C. E. RODES. PERSONAL, RESIDENTIAL AND CENTRAL SITE PM MASS CONCENTRATIONS ASSOCIATED WITH THE DETROIT EXPOSURE AND AEROSOL RESEARCH STUDY ( DEARS ). Presented at 7th International Aerosol Conference (AAAR), Minneapolis, MN, September 10 - 15, 2006.
Abstract: The DEARS is a three year field monitoring study being performed by the US EPA's National Exposure Research Laboratory in the Detroit, Michigan area. Two years of monitoring have been completed and data from the first year of the study is currently being analyzed. This report summarizes the fine particulate matter (PM2.5) mass concentrations observed from personal, residential indoor, residential outdoor and central site monitoring. Mass concentrations from the various monitoring locations as well as the observed residential outdoor composition of the PM2.5 mass are provided. Residential infiltration of PM of ambient origin (Fpex) as well as personal exposure factors (Fpex) observed during the first two seasons are reported.

PRESENTATION The U.S. Environmental Protection Agency Version of Positive Matrix Factorization 09/10/2006
HOPKE, P. K., P. PAATERO, AND S. I. EBERLY. The U.S. Environmental Protection Agency Version of Positive Matrix Factorization. Presented at AAAR Conference, ST. Paul, MN, September 10 - 15, 2006.
Abstract: The abstract describes some of the special features of the EPA's version of Positive Matrix Factorization that is freely distributed. Features include descriptions of the Graphical User Interface, an approach for estimating errors in the modeled solutions, and future developments.

PRESENTATION Organic Molecular Marker Analysis of Low Volume Residential Samples for Source Apportionment in the Detroit Exposure and Aerosol Research Study 09/10/2006
MCDOW, S. R., J. TURLINGTON, D. A. OLSON, L. STOCKBURGER, R. W. WILLIAMS, AND A. F. VETTE. Organic Molecular Marker Analysis of Low Volume Residential Samples for Source Apportionment in the Detroit Exposure and Aerosol Research Study. Presented at International Aerosol Conference (AAAR/ISAM), St. Paul, MN, September 10 - 15, 2006.
Abstract: This abstract describes a poster on results for organic speciation analysis for Detroit Exposure and Aerosol Research Study (DEARS) to be presented at the 2006 International Aerosol Conference sponsored by the American Association for Aerosol Research in St. Paul, Minnesota on September 10-15. Analytical methods suitable for analysis of low volume and high volume samples by gas chromatography/mass spectrometry are reported. Preliminary results and concentration trends for high volume samples at the DEARS central site are presented.

PRESENTATION Evaluation of An Enzyme-Linked Immunosorbent Assay for Biological Monitoring of 3-Phenoxybenzoic Acid in Urine 09/10/2006
VAN EMON, J. M., J. C. CHUANG, J. FINEGOLD, R. M. TREJO, AND J. DURNFORD. Evaluation of An Enzyme-Linked Immunosorbent Assay for Biological Monitoring of 3-Phenoxybenzoic Acid in Urine. Presented at American Chemical Society National Meeting, San Francisco, CA, September 14, 2006.
Abstract: Abstract describes the development of an enzyme-linked immunosorbent assay (ELISA) method for monitoring 2,4-dichlorophenoxyacetic acid (2,4-D exposures). The ELISA is compared with a gas chromatograhy/mass spectrometry procedure. ELISA method development steps and comparative results are given for spiked urine samples.

PRESENTATION Dicarboxylic Acid Concentration Trends and Sampling Artifacts 09/10/2006
MCDOW, S. R. AND J. RAY. Dicarboxylic Acid Concentration Trends and Sampling Artifacts. Presented at International Aerosol Conference (AAR/ISAM), St. Paul, MN, September 10 - 15, 2006.
Abstract: This abstract describes a slide presentation on results of dicarboxylic acid concentration trends and sampling artifacts to be presented at the 2006 International Aerosol Conference sponsored by the American Association for Aerosol Research in St. Paul, Minnesota on September 10-15. Samples were collected in Philadelphia in the summer of 1999 during the Northeast Oxidant and Particulate Study (NEOPS). Implications for accurate sampling of dicarboxylic acids and potential for their use as secondary organic aerosol tracers are discussed.

PRESENTATION An Enzyme Linked Immunosorbent Assay (ELISA) Method for Monitoring 2,4 Dichlorophenoxyacetic Acid (2,4-D) Exposures 09/10/2006
VAN EMON, J. M., J. C. CHUANG, J. DURNFORD, AND K. W. THOMAS. An Enzyme Linked Immunosorbent Assay (ELISA) Method for Monitoring 2,4 Dichlorophenoxyacetic Acid (2,4-D) Exposures. Presented at American Chemical Society National Meeting, San Francisco, CA, September 10 - 14, 2006.
Abstract: Abstract describes a streamlined ELISA method developed to quantitatively measure 2,4-D in human urine samples. Method development steps and comparison with gas chromatography/mass spectrometry are presented. Results indicated that the ELISA method could be used as a high throughput, quantitative monitoring tool for identifying individuals with exposure to 2,4-D above typical background levels.

PRESENTATION Immunoaffinity Chromatography Coupled With LC-MS for the Identification and Determination of Individual Pyrethroids and Their Main Metabolites in Environmental Samples 09/10/2006
XIONG, G. AND J. M. VAN EMON. Immunoaffinity Chromatography Coupled With LC-MS for the Identification and Determination of Individual Pyrethroids and Their Main Metabolites in Environmental Samples. Presented at American Chemical Society 232nd National Meeting, San Francisco, CA, September 10 - 14, 2006.
Abstract: This is an ABSTRACT of an oral presentation which will be given at the 232nd ACS National Meeting. This work describes the development of a novel method for efficient screening and determination of commonly used pyrethroid pesticides and their 3-PBA metabolites based on the combination of immunoaffinity chromatography and liquid chromatography-mass spectrometry techniques.

PRESENTATION Source Apportionment of Fine Particulate Matter in the U.S. and Associations With Lung Inflammatory Markers Il-8, Cox-2 and Ho-1 09/05/2006
DUVALL, R. M., G. A. NORRIS, J. M. BURKE, J. K. MCGEE, M. I. GILMOUR, AND R. B. DEVLIN. Source Apportionment of Fine Particulate Matter in the U.S. and Associations With Lung Inflammatory Markers Il-8, Cox-2 and Ho-1. Presented at International Society of Exposure Analysis, Paris, FRANCE, September 02 - 06, 2006.
Abstract: Associations are well established between particulate matter (PM) and increased human mortality and morbidity. The association between fine PM sources and lung inflammatory markers IL-8, COX-2, and HO-1 was evaluated in this study.

PRESENTATION Measurement Method for Volatile Metabolic Biomarkers in Exhaled Breath Condensate 09/04/2006
PLEIL, J. D. Measurement Method for Volatile Metabolic Biomarkers in Exhaled Breath Condensate. Presented at International Association of Breath Research Workshop, Prague, CZECH REPUBLIC, September 04, 2006.
Abstract: EPA is developing biomarker methodology to interpret spot biological measurements and their linkage to previous environmental pollutants exposures for individuals. This work explores the use of a promising biological media, exhaled breath condensate (EBC), which contains trapped pulmonary aerosols and water soluble endogenous compounds. The desired outcome of this research is to identify patterns of molecules expressed in EBC that will indicate the level of cumulative exposure to groups of compounds from different sources experienced by a human subject.

PRESENTATION Exposure to Volatile Organic Compounds Measured in a Source Impacted Airshed 09/03/2006
VETTE, A. F., D. A. WHITAKER, C. W. CROGHAN, C. D. STEVENS, C. E. RODES, K. OLIVER, H. JACUMIN, AND R. W. WILLIAMS. Exposure to Volatile Organic Compounds Measured in a Source Impacted Airshed. Presented at ISEA/ISEE 2006, Paris, FRANCE, September 02 - 06, 2006.
Abstract: A three-year exposure monitoring study is being conducted in a large city in the Midwestern U.S. The study is aimed at determining the factors influencing exposures to air pollutants of outdoor origin, including volatile organic compounds (VOCs) and particulate matter.

PRESENTATION Develoment and Evaluation of a Model for Estimating Long-Term Average Ozone Exposures to Children 09/02/2006
XUE, J., H. A. OZKAYNAK, V. G. ZARTARIAN, AND J. D. SPENGLER. Develoment and Evaluation of a Model for Estimating Long-Term Average Ozone Exposures to Children. Presented at ISEA/ISEE 2006, Paris, FRANCE, September 02 - 06, 2006.
Abstract: Long-term average exposures of school-age children can be modelled using longitudinal measurements collected during the Harvard Southern California Chronic Ozone Exposure Study over a 12-month period: June, 1995-May, 1996. The data base contains over 200 young children with personal, indoor, and outdoor data, as well as time activity and other questionnaire information collected over a whole year period.

PRESENTATION Prediction of Airborne Pesticide Distributional Parameters By Physiochemical Properties 09/02/2006
EGEGHY, P. P., D. M. STOUT, AND E. J. FURTAW. Prediction of Airborne Pesticide Distributional Parameters By Physiochemical Properties. Presented at ISEA/ISEE 2006, Paris, FRANCE, September 02 - 06, 2006.
Abstract: Results demonstrate that in the absence of a recent application, observed pesticide levels in indoor air are largely a function of their physiochemical properties.

PRESENTATION The Movement of Diazinon Residues Into Holes Following Applications of a Granular Formulation to Residential Lawns 09/02/2006
STOUT, D. M., M. K. MORGAN, AND P. P. EGEGHY. The Movement of Diazinon Residues Into Holes Following Applications of a Granular Formulation to Residential Lawns. Presented at ISEA/ISEE 2006, Paris, FRANCE, September 02 - 06, 2006.
Abstract: Objectives include evaluating methods for collecting environmental samples and examining the transport and fate of diazinon from a source to the indoor living areas of homes.

PRESENTATION Estimation of Children's Exposures Via Poorly Characterized Pathways Using Ctepp Data 09/02/2006
SMITH, J. A., J. C. KISSEL, J. H. SHIRAI, M. K. MORGAN, L. S. SHELDON, AND C. W. CROGHAN. Estimation of Children's Exposures Via Poorly Characterized Pathways Using Ctepp Data. Presented at International Society of Exposure Analysis (ISEA), Paris, FRANCE, September 02 - 06, 2006.
Abstract: This work involved providing better exposure estimates for poorly characterized pathways (dermal and indirect ingestion) for young children in the CTEPP study. The chemicals used in this analysis were chlorpyrifos and its degradation product 3,5,6-trichloro-2-pyridinol.

PRESENTATION Prediction and Evaluation of Dietary Model on Arsenic Exposures Using the Sheds Model 09/02/2006
XUE, J., V. G. ZARTARIAN, AND H. A. OZKAYNAK. Prediction and Evaluation of Dietary Model on Arsenic Exposures Using the Sheds Model. Presented at ISEA/ISEE 2006, Paris, FRANCE, September 02 - 06, 2006.
Abstract: Arsenic (As) is one of the important environmental contaminants with many documented health hazards. Dietary intake is one of the most important exposure pathways for arsenic.

PRESENTATION Within and Between-Person Variation in Environmental Concentrations of Metals, PAHs and Pesticides Measured in NHEXAS-Md 09/02/2006
EGEGHY, P. P. AND J. J. QUACKENBOSS. Within and Between-Person Variation in Environmental Concentrations of Metals, PAHs and Pesticides Measured in NHEXAS-Md. Presented at ISEA/ISEE 2006 , Paris, FRANCE, September 02 - 06, 2006.
Abstract: Results suggest that where information on variance components for a specific chemical in a specific media is not available, a chemical's compound class may provide guidance in selecting sample size and in apportioning resources between numbers of subjects and numbers of repeated measurements.

PRESENTATION Environmental Stressor and Exposure Information for Older Adults 09/02/2006
THOMAS, K. W., S. BUEHLER, N. WILSON, S. GORDON, J. H. RAYMER, L. MICHAEL, AND W. STUDABAKER. Environmental Stressor and Exposure Information for Older Adults. Presented at ISEA/ISEE 2006, Paris, FRANCE, September 02 - 06, 2006.
Abstract: This product describes results of literature and data reviews to identify important chemical and biological stressors in the aging population, summarize extant exposure information, and identify data gaps.

PRESENTATION Development, Validation and Field Use of Novel Method for Extracting and Analyzing Organophosphate (Op) and Pyrethroid Pesticide Metabolites and Creatinine from Commercially Available Disposable Diapers 09/02/2006
NISHIOKA, M., K. ANDREWS, M. MCCAULEY, R. C. FORTMANN, AND J. WILKINS. Development, Validation and Field Use of Novel Method for Extracting and Analyzing Organophosphate (Op) and Pyrethroid Pesticide Metabolites and Creatinine from Commercially Available Disposable Diapers. Presented at ISEA/ISEE 2006 , Paris, FRANCE, September 02 - 06, 2006.
Abstract: The ability to efficiently extract urine from disposable diapers ensures an easy to use urine collection protocol and ready compliance for caregivers of very young children. The use of disposable diapers is also desirable because of their high capacity- urine is retained effectively overnight (12-14 hr for young children), thus providing integration of excretion over 50% of a day.

PRESENTATION SPATIAL ANALYSIS OF AIR POLLUTION AND DEVELOPMENT OF A LAND-USE REGRESSION ( LUR ) MODEL IN AN URBAN AIRSHED 09/02/2006
MUKERJEE, S., L. A. SMITH, X. L. LIAO, L. M. NEAS, C. STALLINGS, AND M. M. JOPHNSON. SPATIAL ANALYSIS OF AIR POLLUTION AND DEVELOPMENT OF A LAND-USE REGRESSION ( LUR ) MODEL IN AN URBAN AIRSHED. Presented at ISEA/ISEE 2006, Paris, FRANCE, September 02 - 06, 2006.
Abstract: The Detroit Children's Health Study is an epidemiologic study examining associations between chronic ambient environmental exposures to gaseous air pollutants and respiratory health outcomes among elementary school-age children in an urban airshed. The exposure component of this study was to use ambient and GIS data from selected school sites to assess spatial variability and develop a land-use regression (LUR) model that could estimate intra-urban gradients of ambient air pollution levels for use in the health assessment.

PRESENTATION Influence of Matrix Formulation on Dermal Percutaneous Absorption of Triazole Fungicides Using QSAR and PBPK/Pd Models 09/02/2006
CHANG, D., P. P. EGEGHY, J. B. KNAAK, R. TORNERO-VELEZ, M. S. OKINO, F. W. POWER, M. DELLARCO, C. S. MAZUR, J. F. KENNEKE, AND C. C. DARY. Influence of Matrix Formulation on Dermal Percutaneous Absorption of Triazole Fungicides Using QSAR and PBPK/Pd Models. Presented at ISEA/ISEE 2006 , Paris, FRANCE, September 02 - 06, 2006.
Abstract: The objective of this work is to use the Exposure Related Dose Estimating Model (ERDEM) and quantitative structure-activity relationship (QSAR) models to develop an assessment tool for human exposure assessment to triazole fungicides. A dermal exposure route is used for the physiological based pharmacokinetic model and matrix formulation effects are simulated for propiconazole.

PRESENTATION Assessing Exposure Factors of Asthmatic Children 09/02/2006
STEVENS, C. D., R. W. WILLIAMS, AND T. R. MCCURDY. Assessing Exposure Factors of Asthmatic Children. Presented at ISEA/ISEE 2006 , Paris, FRANCE, September 02 - 06, 2006.
Abstract: Since 1980, there has been a 75% increase in the prevalence of asthma in children in the U.S.
A pilot study was conducted in a southeastern US city to develop and to evaluate methods and factors associated with asthmatic children's (< 6 yrs.) exposures to air pollutants. Observations support the need to collect data on activities and lifestyle factors in large-scale asthma studies to model asthmatic children's exposures and intake dose rates.

PRESENTATION Levels of 2,4-Dichlorophenoxyacetic Acid in the Homes and Urine of 135 Preschool Children and Their Adult Caregivers in North Carolina and Ohio 09/02/2006
MORGAN, M. K., L. S. SHELDON, C. W. CROGHAN, P. A. JONES, K. W. THOMAS, J. C. CHUANG, AND N. K. WILSON. Levels of 2,4-Dichlorophenoxyacetic Acid in the Homes and Urine of 135 Preschool Children and Their Adult Caregivers in North Carolina and Ohio. Presented at ISEA/ISEE 2006, Paris, FRANCE, September 02 - 06, 2006.
Abstract: This study investigated the aggregate exposures of preschool children and their primary adult caregivers to chemicals commonly found in their everyday environments. One primary objective of this study was to identify the important sources and pathways of the participant's exposures to 2,4-dichlorophenoxyacetic acid (2,4-D) at their homes. 2,4-D is a herbicide that is commonly used in the United States to control for broadleaf weeds in agricultural and residential settings.

PRESENTATION Common Issues in Human and Ecosystem Exposure Assessment: the Significance of Partitioning, Kinetics, and Uptake at Biological Exchange Surfaces 09/02/2006
MCKONE, T., W. J. RILEY, R. MADDALENA, R. ROSEBAUM, AND D. A. VALLERO. Common Issues in Human and Ecosystem Exposure Assessment: the Significance of Partitioning, Kinetics, and Uptake at Biological Exchange Surfaces. Presented at ISEA/ISEE 2006, Paris, FRANCE, September 02 - 06, 2006.
Abstract: Exogenous chemicals enter organisms through critical surfaces in the lung, gills, gut, and skin. Transfer across these boundaries is the first step in characterizing the ratio of tissue dose to external exposure. Surface processes and fugacity are important elements of both human and ecosystem exposure assessments.

PRESENTATION Dietary Exposure to Pyrethroids in the U.S Population 09/02/2006
TORNERO-VELEZ, R., J. XUE, E. SCOLLON, J. M. STARR, P. P. EGEGHY, D. B. BARR, M. J. DEVITO, AND C. C. DARY. Dietary Exposure to Pyrethroids in the U.S Population. Presented at ISEA/ISEE 2006, Paris, FRANCE, September 02 - 06, 2006.
Abstract: We examined the contribution of pyrethroid residues in food as an important driver of exposure. The levels of urinary metabolites of pyrethroids reported in NHANES were used as a general estimate of population exposure to pyrethroids. Dietary exposure to pyrethroids was estimated using the USDA PDP database, and was related to urinary metabolites through pharmacokinetic modeling. Comparison of the predicted metabolites levels with values reported in NHANES suggests that diet is a minor source of pyrethroids.

PRESENTATION American Healthy Homes Survey: A National Study of Residential Related Hazards 09/02/2006
BRADHAM, K. D., R. HIGHSMITH, L. S. SHELDON, D. M. STOUT, S. L. HARPER, S. J. VESPER, P. A. JONES, M. MEDINA-VERA, R. C. FORTMANN, E. A. COPPEDGE, C. W. CROGHAN, W. FRIEDMAN, E. PINZER, P. ASHLEY, D. COX, AND G. DEWALT. American Healthy Homes Survey: A National Study of Residential Related Hazards. Presented at ISEA/ISEE 2006, Paris, FRANCE, September 02 - 06, 2006.
Abstract: The US Environmental Protection Agency's (EPA) National Exposure Research Laboratory (NERL) and the US Department of Housing and Urban Development's (HUD) Office of Healthy Homes and Lead Hazard Control conducted a national survey of housing related hazards in US residences. The collaborative study, the American Healthy Homes Survey (AHHS), was designed to assess residential concentrations of lead, allergens, mold, pesticides, and arsenic for the general population, including but not limited to children and other susceptible subpopulations, to these key hazards.

PRESENTATION Pilot Study of the Potential for Human Exposures to Pet-Borne Diazinon Residues Following Lawn Applications in North Carolina 09/02/2006
MORGAN, M. K., D. M. STOUT, AND D. B. BARR. Pilot Study of the Potential for Human Exposures to Pet-Borne Diazinon Residues Following Lawn Applications in North Carolina. Presented at ISEA/ISEE 2006, Paris, FRANCE, September 02 - 06, 2006.
Abstract: This study examined the potential for indoor/outdoor pet dogs to be an important pathway for transporting diazinon residues into homes and onto occupants following residential lawn applications. The primary objective was to investigate the potential exposures of children and their pet dogs to diazinon after a lawn application at their homes.

PRESENTATION Pesticide Use and Prostate Cancer Incidence in a Prospective Cohort Study 09/02/2006
ALAVANJA, M., L. BEANE-FREEMAN, J. COBLE, J. LUBIN, R. MAHAJAN, J. HOPPIN, K. W. THOMAS, C. HINES, D. SANDLER, AND A. BLAIR. Pesticide Use and Prostate Cancer Incidence in a Prospective Cohort Study. Presented at ISEA/ISEE 2006, Paris, FRANCE, September 02 - 06, 2006.
Abstract: This product describes an analysis of potential associations between pesticide use and prostate cancer in the Agricultural Health Study epidemiological cohort.

PRESENTATION Issues and Challenges in Modeling Children's Longitudinal Exposures: An Ozone Study 09/02/2006
XUE, J., V. G. ZARTARIAN, AND H. A. OZKAYNAK. Issues and Challenges in Modeling Children's Longitudinal Exposures: An Ozone Study. Presented at ISEA/ISEE 2006, Paris, FRANCE, September 02 - 06, 2006.
Abstract: Modeling children's exposures is a complicated, data-intensive process. Modeling longitudinal exposures, which are important for regulatory decision making, especially for most air toxics, adds another level of complexity and data requirements. Because it is difficult to model inter- and intra-personal variability for exposure model inputs, there is potential for inaccurate estimation of upper percentiles of longitudinal exposure distributions

PRESENTATION Urban Scale Variability of PM 2.5 Components 09/02/2006
STEVENS, C. D., R. W. WILLIAMS, A. F. VETTE, AND P. A. JONES. Urban Scale Variability of PM 2.5 Components. Presented at ISEA/ISEE Conference, Paris, FRANCE, September 02 - 06, 2006.
Abstract: This study is being conducted in a large city in the mid-west U.S. The preliminary spatial analyses for particulate nitrate, selected trace elements, and organic and elemental carbon (OC/EC) will be presented.

PRESENTATION Estimates of Age-Specific Urinary Excretion Rates for Creatinine Among Children 09/02/2006
EGEGHY, P. P. AND K. W. THOMAS. Estimates of Age-Specific Urinary Excretion Rates for Creatinine Among Children. Presented at ISEA/ISEE 2006, Paris, FRANCE, September 02 - 06, 2006.
Abstract: The results of this study suggest that naïve adjustment by creatinine concentration, without consideration of the age-dependence of the physiological mechanisms controlling its excretion, may introduce sizeable error and is inappropriate when comparing metabolite concentrations among different age groups.

PRESENTATION Polybrominated Diphenyl Ethers in US Soils 08/21/2006
OFFENBERG, J. H., H. M. STAPLETON, M. J. STRYNAR, AND A. B. LINDSTROM. Polybrominated Diphenyl Ethers in US Soils. Presented at Dioxin 2006, Oslo, NORWAY, August 21 - 25, 2006.
Abstract: Chemical analysis of thirty-three soil samples from 15 US states reveals Polybrominated Diphenyl Ethers (PBDEs), in every sample.PBDE concentrations rangefrom 0.09 to 1200 parts per billion by mass. These data are the first analysis of soil concentrations of PBDEs in soils from across the US, and provide the first demonstration of the ubiquity of PBDEs in US surface soils.

PRESENTATION Size-Segregated Particulate Mercury Measurements in Steubenville, Oh and Detroit, Mi, USA 08/09/2006
LYNAM, M. AND M. S. LANDIS. Size-Segregated Particulate Mercury Measurements in Steubenville, Oh and Detroit, Mi, USA. Presented at 8th International Conference on Mercury, Madison, WI, August 06 - 11, 2006.
Abstract: This poster presents data on size-segregated particulate-phase mercury made during field intensive measurements in Steubenville, OH and Detroit, MI in 2004. The goal was to obtain information about size distribution of particle-associated mercury. A knowledge of size distribution gives rise to improved modeling of dry deposition fluxes of coarse and fine particle mercury and an assessment of the relative importance of each.

PRESENTATION Mercury Emissions from Brake Wear Associated With on-Road Vehicles 08/06/2006
CHRISTIANSON, M. G., G. J. KEELER, M. S. LANDIS, AND A. F. VETTE. Mercury Emissions from Brake Wear Associated With on-Road Vehicles. Presented at International Conference on Mercury as a Global Pollutant, Madison, WI, August 06 - 11, 2006.
Abstract: This paper will focus on brake wear emissions of mercury and trace metals collected from 16 in-use light-duty vehicles (14 gasoline and 2 diesel) on a chassis dynamometer over the course of urban drive cycles.

PRESENTATION Investigating Oxidation Mechanisms of Hgo in the Free Troposphere and Its Influence on Long Range Mercury Transport 08/06/2006
LANDIS, M. S., R. J. STEVENSON, AND G. J. KEELER. Investigating Oxidation Mechanisms of Hgo in the Free Troposphere and Its Influence on Long Range Mercury Transport. Presented at International Conference on Mercury, Madison, WI, August 06 - 11, 2006.
Abstract: ORD initiated automated speciated mercury measurements at the NOAA Mauna Loa Observatory (MLO), a high altitude research station (~11,500 feet) in 2001. Mercury monitoring at MLO was supplemented with trace element aerosol, criteria gas, and gas and particulate halide measurements. Observations at MLO are consistent with aircraft results suggesting that there is a significant Hg0 oxidation mechanism at altitude. These observations are not consistent with the contemporary conceptual atmospheric mercury model that estimates the Hg0 atmospheric lifetime to be approximately 1 year.

PRESENTATION Mercury Emissions from Gasoline and Diesel Powered on-Road Vehicles 08/06/2006
LANDIS, M. S., A. F. VETTE, M. CHRISTIANSON, AND G. J. KEELER. Mercury Emissions from Gasoline and Diesel Powered on-Road Vehicles. Presented at 8th International Conference on Mercury, Madison, WI, August 06 - 11, 2006.
Abstract: Measurements of elemental gaseous mercury (Hg0), divalent reactive gaseous mercury (RGM), and particulate phase mercury (Hg(p)) were made from 14 gasoline and 2 diesel powered in-use light-duty vehicles on a chassis dynamometer. All vehicles were tested under both cold and hot start conditions on a variable speed urban driving cycle. Gas phase species dominated mercury emissions from all vehicles. The mass emission rates and the relative proportion of Hg0 and RGM varied significantly between vehicles and between hot and cold start conditions. Speciated mercury emission rates, mercury in fuel, and mercury in lubricating oil will be presented and discussed.

PRESENTATION Measurement and Modeling of Atmospheric Mercury Species and Related Pollutants in South Florida from 2000-2005 08/06/2006
STEVENS, R. K., M. S. LANDIS, G. J. KEELER, T. D. ATKESON, AND K. LARSON. Measurement and Modeling of Atmospheric Mercury Species and Related Pollutants in South Florida from 2000-2005. Presented at International Conference on Mercury as a Global Pollutant, Madison, WI, August 06 - 11, 2006.
Abstract: In 2000, Florida DEP, USEPA, and Broward EPD located an atmospheric mercury monitoring site adjacent to the Everglades in southeast Florida for the purposes of field testing the Tekran mercury speciation system under long-term operational conditions and evaluating the impact of emissions sources in South Florida. A second site was subsequently established in downtown Ft. Lauderdale in 2001. Rainfall mercury remains high in southern Florida despite striking local emissions reductions in the early
1990¿s, begging the question of what processes underlie this phenomenon? The objective was to obtain data to support modeling of the fate and transport of mercury emission from sources in the region. Measurements will be incorporated into meteorological and receptor models to calculate the fate and transport of mercury. Elevated concentrations of mercury and related species were observed at the Everglades site with prevailing winds from the Ft. Lauderdale/Miami urban area. As part of the modeling, the amount of deposition and or transformations, occurring during transport between the monitoring sites will be estimated.

PRESENTATION Urinary Biomarker Interpretation Using Pharmacokinetic Models 07/26/2006
OKINO, M. S., C. B. THOMPSON, F. W. POWER, R. TORNERO-VELEZ, A. TSANG, J. N. BLANCATO, AND C. C. DARY. Urinary Biomarker Interpretation Using Pharmacokinetic Models. Presented at International Council of Chemistry Associations Workshop, Minneapolis, MN, July 26 - 27, 2006.
Abstract: The issues involved with applying PBPK models in urinary biomarker interpretation were presented. Example scenarios were modeled, and absorbed doses were estimated for selected participants from a field study to illustrate the applicability and limitations of the methods.

PRESENTATION Impacts of Traffic on Air Quality and Health Effects Near Major Roadways 07/12/2006
BALDAUF, R. W., C. BAILEY, P. T. ROWLEY, M. HOYER, AND R. COOK. Impacts of Traffic on Air Quality and Health Effects Near Major Roadways. Presented at Urban Transport 2006, Prague, CZECH REPUBLIC, July 12 - 14, 2006.
Abstract: A growing number of epidemiological studies conducted in Europe, Asia, and North America have identified an increase in occurrence of adverse health effects for populations living near major roads. However, the biological mechanism(s) leading to the adverse effects have not been identified. Limitations in exposure assessment have resulted in a need to evaluate and improve methods of predicting exposures in the near road environment. Questions remain on the spatial extent of the zone of influence of the road, and the factors affecting concentration variability including traffic volume, vehicle fleet mix, and fleet operating characteristics. In the U.S., federal agencies have been under increasing pressure to evaluate potential air quality and health impacts from transportation systems.
This paper will provide a summary of studies evaluating near road health effects, air quality and population exposures. The paper will focus on work conducted in the United States, although several studies from Europe have been included. A significant amount of work has also been conducted in Europe and Asia, generally indicating similar results.

PRESENTATION The US EPA Implementation of Positive Matrix Factorization and a New Approach to Uncertainty Emissions 07/09/2006
HOPKE, P. K., P. PAATERO, AND S. I. EBERLY. The US EPA Implementation of Positive Matrix Factorization and a New Approach to Uncertainty Emissions. Presented at International Environmental Modeling and Software Society , Burlington, VT, July 09 - 13, 2006.
Abstract: This abstract describes the approach implemented in EPA's version of Positive Matrix Factorization (EPA PMF) to estimate uncertainties in the modeled solutions. Details are provided regarding sources of uncertainty in constrained factor analytic models and how these approaches are addressed with bootstrapping and pulling, the techniques used in EPA PMF. Results using simulated and real data are presented.

PRESENTATION Suggestions for Optimized Planning of Multivariate Monitoring of Atmospheric Pollution 07/09/2006
PAATERO, P., S. I. EBERLY, AND P. K. HOPKE. Suggestions for Optimized Planning of Multivariate Monitoring of Atmospheric Pollution. Presented at International Environmental Modeling and Software Society, Burlington, VT, July 09 - 13, 2006.
Abstract: Recent work in factor analysis of multivariate data sets has shown that variables with little signal should not be included in the factor analysis. Work also shows that rotational ambiguity is reduced if sources impacting a receptor have both large and small contributions. These two aspects are important for designing field studies involving receptor modeling.

PRESENTATION Closure Between Semi-Continuous Measurement of PM 2.5 Mass and Composition 06/21/2006
GLOVER, B. D., D. J. EATOUGH, W. R. WOOLWINE, J. CANNON, N. L. EATOUGH, R. W. LONG, AND R. A. CARY. Closure Between Semi-Continuous Measurement of PM 2.5 Mass and Composition. Presented at 99th Air & Waste Management Association Annual Conference, New Orleans, LA, June 20 - 23, 2006.
Abstract: This extended abstract reports the first successful attempt to quantitatively measure all the major species of PM2.5 on a semi-continuous basis. Comparisons are made between both PC-BOSS integrated species concentration measurements with semi-continuous species measurements and of measured semi-continuous mass with constructed semi-continuous mass.

PRESENTATION Associations Between Fine Particulate Matter Sources and Health Effects 05/18/2006
DUVALL, R. M., G. A. NORRIS, J. M. BURKE, J. K. MCGEE, M. I. GILMOUR, AND R. B. DEVLIN. Associations Between Fine Particulate Matter Sources and Health Effects. Presented at EPA Science Forum 2006, Washington, DC, May 16 - 18, 2006.
Abstract: Associations are well established between particulate matter (PM) and increased human mortality and morbidity. The toxicity of PM may differ depending on the type of PM source, and health impacts may vary by location depending on the mix of PM sources impacting each location. The association between PM sources and health effects was evaluated in this study.

PRESENTATION Improving Exposure Data Inputs Needed to Assess Environmental Risks of Older Adults 05/17/2006
THOMAS, K. W., N. S. TULVE, T. R. MCCURDY, M. S. OKINO, AND L. J. MELNYK. Improving Exposure Data Inputs Needed to Assess Environmental Risks of Older Adults. Presented at EPA Science Forum - 2006, Washington, DC, May 16 - 18, 2006.
Abstract: An abstract has been prepared for the 2006 EPA Science forum that describes work to develop a scientific understanding of differential exposures, activities, and dose in aging populations and potentially susceptible subpopulations. When combined with information being developed on age-related changes in pharmacokinetics and physiological parameters, this research is expected to reduce uncertainties in risk assessment through understanding and elucidating the fundamental determinants of exposure and dose.

PRESENTATION Integrated Laboratory and Field Characterization of Organic Carbon in PM 2.5 Formed Through Chemical Reactions 05/17/2006
OFFENBERG, J. H., T. KLEINDIENST, E. O. EDNEY, M. LEWANDOWSKI, AND MOHAMMAD JAOUI. Integrated Laboratory and Field Characterization of Organic Carbon in PM 2.5 Formed Through Chemical Reactions. Presented at EPA Science Forum 2006, Washington, DC, May 16 - 18, 2006.
Abstract: An integrated laboratory and field research program is underway at the National Exposure Research Laboratory (NERL) to characterize organic carbon in PM2.5 (particulate matter) formed through chemical reactions. Information from this study will provide critical data needed to improve the treatment of secondary organic aerosol (SOA) formation in the Community Multiscale Air Quality (CMAQ) model.

PRESENTATION Innovative Tools and Methods for Assessing Children's Potential Chemical Exposure 05/16/2006
TULVE, N. S., K. DEENER, C. SAINT, E. A. COHEN-HUBAL, L. J. MELNYK, L. S. SHELDON, AND D. STOUT. Innovative Tools and Methods for Assessing Children's Potential Chemical Exposure. Presented at EPA Science Forum 2006, Washington, DC, May 16 - 18, 2006.
Abstract: Children's exposures to environmental contaminants are different than adults, due in part to differences in physiologic functions. Research on children's exposure to environmental contaminants is currently being performed within EPA, academia, industry, and other research organizations.

PRESENTATION Estimation of Chemical Specific Parameters Within Physiologically Based Pharmacokinetic/Pharmacodynamic Models 05/16/2006
CHANG, D., M. S. OKINO, FRED W. POWER, R. TORNERO-VELEZ, J. F. KENNEKE, CHRIS S. MAZUR, C. C. DARY, AND TIM W. COLLETTE. Estimation of Chemical Specific Parameters Within Physiologically Based Pharmacokinetic/Pharmacodynamic Models. Presented at EPA Science Forum 2006, Washington, DC, May 16 - 18, 2006.
Abstract: While relationships between chemical structure and observed properties or activities (QSAR - quantitative structure activity relationship) can be used to predict the behavior of unknown chemicals, this method is semiempirical in nature relying on high quality experimental data to construct statistically relevant relationships for a set of chemically similar compounds (congeners).

PRESENTATION Important Factors Influencing Children's Exposure to Pesticides 05/16/2006
EGEGHY, P. P., N. S. TULVE, D. M. STOUT, M. K. MORGAN, L. J. MELNYK, E. A. COHEN-HUBAL, R. C. FORTMANN, AND L. S. SHELDON. Important Factors Influencing Children's Exposure to Pesticides. Presented at EPA Science Forum 2006, Washington, DC, May 16 - 18, 2006.
Abstract: The Children's Exposure Research Program in the National Exposure Research Laboratory has supported numerous laboratory and field studies to reduce uncertainty in the exposure estimates with the goal of ensuring that pesticides are regulated appropriately. These studies were conducted to identify pesticide use patterns, measure pesticide concentrations in homes and day care centers, describe spatial and temporal distributions of pesticide concentrations following residential applications, evaluate approaches for estimating dermal and non-dietary exposure, and characterize activity patterns of young children.

PRESENTATION Air Quality Characterization of Environmental Public Health Tracking 05/16/2006
WATKINS, T. H., F. DIMMICK, D. M. HOLLAND, T. L. CONNER, A. GILLILAND, V. BOOTHE, C. PAULU, AND A. SMITH. Air Quality Characterization of Environmental Public Health Tracking. Presented at 28th NATO/CMMS International Technical Meeting, Leipzig, GERMANY, May 16 - 19, 2006.
Abstract: The EPA and the CDC have conducted a collaborative effort entitled the Public Health Air Surveillance Evaluation (PHASE) to pilot the development of integrated air quality data sets, from routinely available sources, for specific use by public health officials.

PRESENTATION Interpreting Biomarkers of Exposure Inb Humans 05/16/2006
MORGAN, M. K. AND L. S. SHELDON. Interpreting Biomarkers of Exposure Inb Humans. Presented at EPA Science Forum 2006, Washington, DC, May 16 - 18, 2006.
Abstract: This is a presentation for EPA's 2006 Science Forum in Washington, DC. It discusses the important research area on interpreting biomarkers of exposure in humans.

PRESENTATION Source Apportionment Results, Uncertainties, and Modeling Tools 05/15/2006
DUVALL, R. M., G. A. NORRIS, AND S. R. MCDOW. Source Apportionment Results, Uncertainties, and Modeling Tools. Presented at Krakow Integrated Project, Krakow, POLAND, May 15 - 16, 2006.
Abstract: Advanced multivariate receptor modeling tools are available from the U.S. Environmental Protection Agency (EPA) that use only speciated sample data to identify and quantify sources of air pollution. EPA has developed both EPA Unmix and EPA Positive Matrix Factorization (PMF) and the programs are available to the public as easy to use stand-alone programs. These programs use two different approaches to separate out sources with Unmix using only the species concentration data, while PMF requires a combination of species concentration and uncertainty data. This work presents the following topics: (1) review of the EPA PMF 1.1 and EPA Unmix 5.0 multivariate receptor models, (2) application of these models to PM10 data collected in Krakow, Poland, (3) challenges in U.S. source apportionment, and (4) efforts to reduce uncertainty in source apportionment.

PRESENTATION Verification of Ambient Monitoring Technologies for Ammonia and Hydrogen Sulfide at Animal Feeding Operations 05/10/2006
SUMNER, A. L., K. A. COWEN, A. B. DINDAL, K. B. RIGGS, J. L. HATFIELD, R. L. PFEIFFER, K. D. SCOGGINS, E. D. WINEGAR, AND R. G. FUERST. Verification of Ambient Monitoring Technologies for Ammonia and Hydrogen Sulfide at Animal Feeding Operations. Presented at Air and Waste Management Association, Durham, NC, May 09 - 11, 2006.
Abstract: The increasing concentration of livestock agriculture into animal feeding operations (AFOs) has raised concerns about the environmental and potential health impact of the emissions from AFOs into the atmosphere. Gaseous ammonia (NH3) and hydrogen sulfide (H2S), byproducts of animal wastes, are emitted from AFOs into the atmosphere. In 2002, the U.S. Environmental Protection Agency (EPA) estimated that agricultural activities accounted for 65% of the total NH3 emissions into the atmosphere. Ammonia impacts regional and national air quality, specifically through nitrogen deposition and production of atmospheric haze, due to its ability to form ammonium sulfate and nitrate aerosols. NH3 can also impact human health at high levels [i.e., greater than 50 parts per million (ppm)] and has a strong, sharp characteristic odor. Emissions of H2S from AFOs, on the other hand, are unlikely to have a significant influence on regional or national air quality, but may have a significant affect nearby AFOs; H2S is a component of "sewer gas" and has the generally objectionable odor of rotten eggs, which can decrease the quality of life in the proximity of H2S sources. However, the ability to smell H2S can dull or deaden at levels higher than approximately 50 ppm, and H2S is toxic at levels greater than 500 ppm.

PRESENTATION Semi-Continuous Determination of Water-Soluble Particulate Components and Their Gaseous Precursors: Laboratory and Field Evaluation of Instrumentation Based on Wet Wall Denuder and Ion Chromatography Technology 05/10/2006
LONG, R. W., M. S. LANDIS, K. KRONMILLER, B. D. GROVER, D. J. EATOUGH, R. K. STEVENS, AND R. AL-HORR. Semi-Continuous Determination of Water-Soluble Particulate Components and Their Gaseous Precursors: Laboratory and Field Evaluation of Instrumentation Based on Wet Wall Denuder and Ion Chromatography Technology. Presented at AWMA Symposium, Durham, NC, May 09 - 11, 2006.
Abstract: Research conducted by EPA at its facility in Research Triangle Park, NC and by EPA, Brigham Young University (BYU), and others during field intensive studies in California, Utah and Florida has demonstrated the capability for the semi-continuous determination of water-soluble particulate components (SO42-, NO3-, NO2-, Cl-, and NH4+) and gaseous precursors (SO2, HNO3, HONO, HCl, and NH3) using instrumentation based on wet wall denuder (WWD) and ion chromatography (IC) technology. Two instruments, an IC-based prototype monitor developed at Texas Tech University (TTU) and a Dionex Gas-Particle Ion Chromatograph (GPIC), were evaluated in the laboratory using simulated ambient aerosols and gases to compare their response to other measurement methods under controlled conditions and to identify potential sampling artifacts that might occur under ambient conditions. The instruments were also evaluated during field intensive studies in Rubidoux, CA (July 2003); Fresno, CA (December 2003); Lindon, UT (February 2005); Tampa, FL (May 2005); and Riverside, CA (July-August 2005) during which results obtained from the WWD-IC based instruments were compared to results obtained from additional semi-continuous and integrated methods for the determination of water-soluble particulate components and/or their gaseous precursors. Results from the laboratory and field evaluations will be presented.

PRESENTATION Passive Aerosol Sampler for Characterization, Ambient Concentration, and Particle Size Measurement 05/09/2006
WAGNER, J., D. LEITH, G. CASUCCIO, T. MERRIFIELD, T. PETERS, AND R. WILLIS. Passive Aerosol Sampler for Characterization, Ambient Concentration, and Particle Size Measurement. Presented at Symposium on Air Quality Measurement Methods and Technology, Durham, NC, May 09 - 11, 2006.
Abstract: This is an extended abstract of a presentation made at the Air and Waste Management Association's Symposium on Air Quality Measurement Methods and Technology, Durham, NC, May 9-11, 2006. The abstract describes the theory, design, and initial testing of a passive aerosol sampler for PM2.5, PM10, and PM10-2.5 .

PRESENTATION Use of Passive Samplers in the Dears 05/09/2006
WILLIAMS, R. W., A. F. VETTE, D. A. WHITAKER, C. W. CROGHAN, P. A. JONES, H. DAUGHTREY, K. OLIVER, H. JACUMIN, D. WILLIAMS, C. E. RODES, J. THORNBURG, J. HERRINGTON, L. ZHANG, AND J. ZHANG. Use of Passive Samplers in the Dears. Presented at Symposium on Air Quality measurement Methods and Technology (AWMA), Durham, NC, May 09 - 11, 2006.
Abstract: The Detroit Exposure and Aerosol Research Study (DEARS) employs a number of passive diffusion-based samplers for the collection of select gaseous air pollutants. These pollutants include criteria gases such as ozone, carbonyls such as acrolein, and volatile organics such as 1-3, butadiene. The use, range of applicability, and preliminary data quality findings from the first two seasons of the DEARS will be reported in this presentation.

PRESENTATION Passive Aerosol Sampler for PM 10-2.5 05/09/2006
LEITH, D., T. MERRIFIELD, R. WILLIS, T. L. CONNER, M. BOUNDY, J. WAGNER, G. CASUCCIO, AND T. PETERS. Passive Aerosol Sampler for PM 10-2.5. Presented at Symposium on Air Quality Measurement Methods and Technology, Durham, NC, May 09 - 11, 2006.
Abstract: This is an extended abstract of a presentation made at the Air and Waste Management Association's Symposium on Air Quality Measurement Methods and Technology, Durham, NC, May 9-11, 2006. The abstract describes the application of a passive aerosol sampler for coarse PM characterization.

PRESENTATION Evaluation of PM 10, PM 2.5 and PM 10-2.5 Measurements Using a Passive Particulate Sampler 05/09/2006
WILLIS, R., D. LEITH, T. MERRIFIELD, J. WAGNER, G. CASUCCIO, C. COWLEY, T. L. CONNER, AND T. PETERS. Evaluation of PM 10, PM 2.5 and PM 10-2.5 Measurements Using a Passive Particulate Sampler. Presented at Symposium on Air Quality Measurement Methods and Technology, Durham, NC, May 09 - 11, 2006.
Abstract: This is an extended abstract of a presentation made at the Air and Waste Management Association's Symposium on Air Quality Measurement Methods and Technology, Durham, NC, May 9-11, 2006. The abstract describes field evaluations of a passive aerosol sampler for PM2.5, PM10, and PM10-2.5 .

PRESENTATION Developing a Quality System for the National Children's Study 04/25/2006
MICHAEL, D., K. HULL, J. J. QUACKENBOSS, AND E. J. KANTOR. Developing a Quality System for the National Children's Study. Presented at Conference on Managing Environmental Quality Systems, Austin, TX, April 24 - 27, 2006.
Abstract: A Quality Management Plan (QMP) is under development for a national, interagency, long-term study known as the National Children's Study (NCS). The NCS is a study to examine the effects of environmental influences on the health and development of more than 100,000 children across the United States, following them from before birth until age 21.

PRESENTATION Highly Selective Sensors for Chemical and Biological Warfare Agents, Insecticides and Vocs Based on a Molecular Surface Imprinting Technique 03/15/2006
ZHOU, Y., R. TSUI, G. MARACAS, J. M. VAN EMON, AND K. LEVON. Highly Selective Sensors for Chemical and Biological Warfare Agents, Insecticides and Vocs Based on a Molecular Surface Imprinting Technique. Presented at Pittsburgh Conference (Pittcon) 2006, Orlando, FL, March 12 - 17, 2006.
Abstract: Abstract was given as an oral platform presentation at the Pittsburgh Conference, Orlando FL (March 5-9, 2006). Research described is the development of sensors based on molecular surface imprinting. Applications include the monitoring of chemical and biological agents and insecticides.

PRESENTATION Evaluation of Multiple Pharmacokinetic Modeling Structures for Trichloroethylene 03/08/2006
OKINO, M. S., M. V. EVANS, FRED W. POWER, W. A. CHIU, J. C. LIPSCOMB, J. N. BLANCATO, AND C. CHEN. Evaluation of Multiple Pharmacokinetic Modeling Structures for Trichloroethylene. Presented at Society of Toxicology, San Diego, CA, March 05 - 09, 2006.
Abstract: A series of PBPK models were developed for trichloroethylene (TCE) to evaluate biological processes that may affect the absorption, distribution, metabolism and excretion (ADME) of TCE and its metabolites.

PRESENTATION USE OF EXPOSURE RELATED DOSE ESTIMATING MODEL ( ERDEM ) TO CONSTRUCT A PBPK /MODEL FOR CARBOFURAN WITH THE REPORTED EXPERIMENTAL DATA IN THE RAT 03/07/2006
ZHANG, X., M. S. OKINO, FRED W. POWER, J. B. KNAAK, A. M. TSANG, L. S. HARRISON, A. O. RUIZ, C. B. THOMPSON, AND C. C. DARY. USE OF EXPOSURE RELATED DOSE ESTIMATING MODEL ( ERDEM ) TO CONSTRUCT A PBPK /MODEL FOR CARBOFURAN WITH THE REPORTED EXPERIMENTAL DATA IN THE RAT. Presented at Society of Toxicology, San Diego, CA, March 05 - 09, 2006.
Abstract: To better understand the relationships among carbofuran exposure, dose, and effects, a physiologically-based pharmacokinetic and pharmacodynamic (PBPK/PD) model was developed for the rat using the Exposure Related Dose Estimating Model (ERDEM) framework.

PRESENTATION Development of a Physiologically Based Pharmacokinetic Model for Deltamethrin in Developing Sprague-Dawley Rats 03/07/2006
MIRFAZAELIAN, A., K. KIM, S. S. ANAND, S. LEE, H. J. KIM, R. TORNERO-VELEZ, J. V. BRUCKNER, AND J. W. FISHER. Development of a Physiologically Based Pharmacokinetic Model for Deltamethrin in Developing Sprague-Dawley Rats. Presented at Society of Toxicology, San Diego, CA, March 05 - 09, 2006.
Abstract: This work describes the development of a physiologically based pharmacokinetic (PBPK) model of deltamethrin, a type II pyrethroid, in the developing male Sprague-Dawley rat. Generalized Michaelis-Menten equations were used to calculate metabolic rate constants and organ weights of rats of different ages. The PBPK model predictions compared favorably with experimental blood, brain and fat DLT profiles over the range of doses. The model will aid in our understanding of the processes affecting the disposition of pyrethroids in humans.

PRESENTATION Development of a Physiologically Based Pharmacokinetic Model for Deltamethrin in Adult and Developing Sprague-Dawley Rats 03/07/2006
MIRFAZAELIAN, A., K. KIM, S. S. ANAND, H. J. KIM, R. TORNERO-VELEZ, J. V. BUCKNER, AND J. W. FISHER. Development of a Physiologically Based Pharmacokinetic Model for Deltamethrin in Adult and Developing Sprague-Dawley Rats. Presented at Society of Toxicology, San Diego, CA, March 05 - 09, 2006.
Abstract: This work describes the development of a physiologically based pharmacokinetic (PBPK) model of deltamethrin, a type II pyrethroid, in the developing male Sprague-Dawley rat. Generalized Michaelis-Menten equations were used to calculate metabolic rate constants and organ weights of rats of different ages. The PBPK model predictions compared favorably with experimental blood, brain and fat DLT profiles over the range of doses. The model will aid in our understanding of the processes affecting the disposition of pyrethroids in humans.

PRESENTATION PHYSIOLOGICALLY-BASED PHARMACOKINETIC ( PBPK ) MODEL FOR METHYL TERTIARY BUTYL ETHER ( MTBE ): A REVIEW OF EXISTING MODELS 03/06/2006
POWER, FRED W., J. N. BLANCATO, M. V. EVANS, A. TSANG, AND J. C. CALDWELL. PHYSIOLOGICALLY-BASED PHARMACOKINETIC ( PBPK ) MODEL FOR METHYL TERTIARY BUTYL ETHER ( MTBE ): A REVIEW OF EXISTING MODELS. Presented at Society of Toxicology, San Diego, CA, March 05 - 09, 2006.
Abstract: MTBE is a volatile organic compound used as an oxygenate additive to gasoline, added to comply with the 1990 Clean Air Act. Previous PBPK models for MTBE were reviewed and incorporated into the Exposure Related Dose Estimating Model (ERDEM) software. This model also included an explicit pulmonary compartment. Organs (compartments) included in the model were: liver (for metabolism), fat, kidney, brain, and slowly and rapidly perfused compartments. Both inhalation and oral dosing were included as routes of exposure. Numerous simulations were performed to compare performance between present and previous MTBE PBPK models with available data : (400 and 8000 ppm inhalation exposure for 6 hours, and oral dosing of 40 and 400 mg/kg to a 215g rat). Physiological and metabolic parameters were changed to human values and model performance was re-examined. Using available human data (inhalation, dermal and oral exposures), model comparisons were matched to MTBE peak values, and peak concentration for the metabolite TBA. An uncertainty analysis (representing errors due to parameters or model structure) and variability analysis (attempting to include assumed changes due to differences in the general population) was performed for rat. The simulation results showed model fit for peak MTBE levels to be similar for rat and human.
This work was reviewed by EPA and approved for publication but does not necessarily reflect official Agency policy.

PRESENTATION The U.S. National Children's Study 02/23/2006
QUACKENBOSS, J. J. The U.S. National Children's Study. Presented at International Symposium on Children's Environmental Health, Tokyo, JAPAN, February 23 - 24, 2006.
Abstract: The National Children's Study (NCS) is a study to examine the effects of environmental influences on the health and development of more than 100,000 children across the United States, following them from before birth until age 21. The goal of the study is to understand the factors that are responsible for the physical and mental health of children.

PRESENTATION PUBLIC HEALTH AIR SURVEILLANCE EVALUATION ( PHASE ): WHAT IS IT? WHERE HAS IT BEEN? WHERE IS IT GOING? 02/06/2006
DIMMICK, F. PUBLIC HEALTH AIR SURVEILLANCE EVALUATION ( PHASE ): WHAT IS IT? WHERE HAS IT BEEN? WHERE IS IT GOING? Presented at Air Quality Conference, San Antonio, TX, February 05 - 08, 2006.
Abstract: NERL's Human Exposure and Atmospheric Sciences Division and other participants in the Public Health Air Surveillance Evaluation (PHASE) project will be discussing their results at the EPA Air Quality Conference in San Antonio, Texas on February 6, 2006. The PHASE project is a collaboration between the EPA, CDC and the States of Maine, New York and Wisconsin. The objective of this collaboration is to develop, evaluate, and demonstrate the advantages and limitations of different methods of generating air quality characterization surveillance data that could be systematically and routinely available to link with public health surveillance data as part of the CDC's Environmental Public Health Tracking Network. EPA has provided air quality data for ozone and fine particles based on ambient air monitors, an application of the EPA/NOAA Community Multiscale Air Quality model, and statistically developed estimates.

PRESENTATION Public Health Air Surveillance Evaluation (Phase) a Summary 01/25/2006
DIMMICK, F. Public Health Air Surveillance Evaluation (Phase) a Summary. Presented at European Comission, Directorate General Environment, and French Agency for Environmental and Occupational Health Safety, Research Triangle Park, NC, January 25, 2006.
Abstract: NERL's Human Exposure and Atmospheric Sciences Division and other participants in the Public Health Air Surveillance Evaluation (PHASE) project will be discussing their results with European Commission, Directorate General Environment, and
French Agency for Environment and Occupational Health Safety in RTP, NC on January 25, 2006. The PHASE project is a collaboration between the EPA, CDC and the States of Maine, New York and Wisconsin. The objective of this collaboration is to develop, evaluate, and demonstrate the advantages and limitations of different methods of generating air quality characterization surveillance data that could be systematically and routinely available to link with public health surveillance data as part of the CDC's Environmental Public Health Tracking Network. EPA has provided air quality data for ozone and fine particles based on ambient air monitors, an application of the EPA/NOAA Community Multiscale Air Quality model, and statistically developed estimates.

PRESENTATION Biomonitoring: Interpretation and Uses 01/18/2006
SHELDON, L. S., M. K. MORGAN, AND J. D. PLEIL. Biomonitoring: Interpretation and Uses. Presented at Internation al Life Sciences Institute Annual Meeting, San Juan, PUERTO RICO, January 16 - 19, 2006.
Abstract: With advanced technologies, it is now possible to measure very low levels of many chemicals in biological fluids. However, the appropriate use and interpretation of biomarkers will depend upon many factors associated with the exposure, adsorption, deposition, metabolism, and elimination of these chemicals. Current ORD exposure research is directed toward developing the processes, tools, and information to put biomonitoring data into perspective for the risk assessment process, to define the appropriate uses of specific biomarkers, and to integrate biomarker measurements with exposure and internal dose. Modeling tools will be used to help select approaches for collecting biomonitoring data and to identify data gaps that limit interpretation. Measurement studies, modeling, and data analysis will be used to fill these knowledge gaps and to quantify the relationship between biomarkers, exposure, and internal dose. Modeling and advanced statistical analysis will be used to define the relationship between environmental concentrations and biomarkers. This information will be used to predict changes in biomarker concentrations that may result from changes in environmental concentrations. Research in metabonomics and genomics will allow us to develop and interpret biomarkers of effects resulting from exposures to environmental stressors and to identify sensitive phenotypes.
Results from this research program will allow the Agency to generate meaningful biomonitoring data and to make better use of the available data. Potential uses may include identifying susceptible populations, identifying emerging chemical risks, evaluating tends in exposures, conducting epidemiology studies, and evaluating the impact of risk reduction strategies.

PRESENTATION Biomoniitoring Research Within the U.S. EPA's Office of Research and Development 01/17/2006
SHELDON, L. S. Biomoniitoring Research Within the U.S. EPA's Office of Research and Development. Presented at 2006 ILSI Annual Meeting , San Juan, PUERTO RICO, January 13 - 19, 2006.
Abstract: Current ORD exposure research is directed toward developing the processes, tools, and information to put biomonitoring data into perspective for the risk assessment process, to define the appropriate uses of specific biomarkers, and to integrate biomarker measurements with exposure and internal dose

PUBLISHED REPORT Summary of EPA's Particulate Matter Supersites Program: Results That Can Be Used to Prepare and Evaluate State Implementation Plans (Sips) 12/12/2006
SOLOMON, P. A. Summary of EPA's Particulate Matter Supersites Program: Results That Can Be Used to Prepare and Evaluate State Implementation Plans (Sips). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-06/154 (NTIS PB2007-103430), 2006.
Abstract: In 1999, the United States Environmental Protection Agency (EPA) initiated a major air quality program referred to as the Particulate Matter (PM) Supersites Program. The PM Supersites Program is a multi-year, $27 million air quality program consisting of eight (8) regional air quality projects located throughout the US, each with differing atmospheric pollution conditions resulting from variations in source emissions and meteorology. The overall goal of the program was to elucidate source–receptor relationships and atmospheric processes leading to PM accumulation on urban and regional scales, and thus provide the scientific foundation for modeling and data analysis efforts to support the development of State Implementation Plans (SIPs) and more effective risk management approaches for PM. The program had three main objectives: 1) develop and evaluate measurement methods, 2) characterize ambient PM, and 3) support health and exposure studies. To facilitate communication of results to key stakeholders a synthesis of key scientific findings and based on those findings, policy- and health-relevant findings and knowledge gaps is being developed. Technical responses to these questions were addressed by Supersites Program PIs and their teams, each choosing two to address. The product described here summarizes the accomplishments of the Supersites Program and how they can be used in support of developing SIPs.
A major theme throughout all Supersites Projects was the evaluation and advancement of continuous and semi-continuous measurement methods for PM mass, components of mass, and physical properties of PM. With the inclusion of size distribution measurements and particle mass spectrometers at multiple sites, significant advancements were made towards understanding the formation and growth of ultrafine PM. Application of continuous methods also provided unique opportunities for improving our ability to link ambient concentrations of PM to their sources using advanced receptor-oriented models that integrated hourly data with meteorological variables, allowing source contributions to be apportioned not only to source categories but also to specific sources. While just in initial phases, it is already apparent that the use of continuous data collected in multiple locations can provide important datasets for evaluation and application of source-oriented models. Some results are already leading to changes in model formulations as well as indicating the effect of precursor controls on PM components and ozone. Overall, results from the Supersites Program and related studies have reduced the uncertainty associated with our understanding of the formation and accumulation of PM in air and the linking of ambient PM to its sources.

This report includes discussions on how the Supersites Program has already supported SIP efforts in several locations throughout the US. In the appendices, a series of detailed tables are provided as details and extensive references supporting the findings provided in this abbreviated report.


PUBLISHED REPORT Construction of a Physiologically Based Pharmacokinetic/Pharmacodynamic (PBPK/Pd) Model for Carbofuran Using the Exposure Related Dose Estimating Model (Erdem) 10/20/2006
ZHANG, X., A. M. TSANG, M. S. OKINO, F. W. POWER, J. B. KNAAK, AND C. C. DARY. Construction of a Physiologically Based Pharmacokinetic/Pharmacodynamic (PBPK/Pd) Model for Carbofuran Using the Exposure Related Dose Estimating Model (Erdem). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-06/135 (NTIS PB2007-100680), 2006.
Abstract: Carbofuran, known as 2, 3-dihydro-2, 2-dimethyl-7-benzofuranyl-N-methylcarbamate, is a broad spectrum N-methyl carbamate pesticide. Carbofuran and its metabolite, 3-hydroxycarbofuran, exert their toxicity by reversibly inhibiting acetylcholinesterase (AChE). Carbofuran is widely used in agriculture for pest control. Agricultural workers and the general population may be exposed to it by dermal contact, inhalation, or ingestion as a result of its application or by food intake. To better characterize the human health risk caused by carbofuran exposure, a physiologically-based pharmacokinetic/ pharmacodynamic (PBPK/PD) model was developed in the Exposure Related Dose Estimating Model (ERDEM) system in order to facilitate an understanding of carbofuran's absorption, distribution, metabolism, elimination (ADME) processes, and AChE inhibition effects for the rat. To obtain relevant experimental measurements and the estimates of physiological, biochemical, and physicochemical parameters for the model, literature reviews were conducted. The focus was placed on oral exposure and modeling carbofuran metabolism in the liver to 16 known metabolites, the enterohepatic circulation of glucuronide conjugates, and the excretion to urine and feces. Cholinesterase inhibition by carbofuran and 3-hydroxycarbofuran is modeled in the blood and brain.
Generally, the model simulated results were consistent with available experimental measurements. Following an oral exposure of 50 µg/kg carbofuran, the model predicted that the minimum blood AChE activity occurred at 22 minutes as the enzyme activity was inhibited by 40%, comparing with 15 minutes (37%) reported by Ferguson et al., (1984). The model also suggested that carbofuran had a short half-life of 5.2 hrs; the inhibition capability of carbofuran (ki = 1.6 x 105 L mmol-1 H-1) was about 2.7 times that of 3-hydroxycarbofuran (ki = 6 x 104 L mmol-1 H-1); and a NOAEL value for acute single oral exposure in the rat was about 10 µg/kg using the blood AChE activity as the toxicological endpoint. To identify parameters that had the greatest impact on the simulated dose metrics in urine and blood for the oral exposure scenario, global relative ratios from a sensitivity analysis were calculated based on the boundary values (i.e., 5th and 95th percentiles of each model parameter). Ultimately, thirty sensitive parameters, which included major compartment blood flows and volumes, main metabolic reactions, partition coefficients of major metabolites in main compartments, and the urinary excretion of major metabolites, were found and chosen for constructing Monte Carlo simulations. Results of the simulation runs indicated that following oral exposure to 50 µg/kg carbofuran the minimum AChE activity in the blood ranged from 29.3% to 79.0% (as 5th and 95th percentiles) with a mean of 55.9% (SD = 15.1%); and the minimum AChE activity in the brain ranged from 8.6% to 61.3% (as 5th and 95th percentiles) with a mean of 32.0% (SD = 16.2%). The results of this carbofuran study, and the resulting rat PBPK/PD model, provide a good framework for future risk assessment activities.

PUBLISHED REPORT Multi-Site Evaluations of Candidate Methodologies for Determining Coarse Particulate (PM 10-2.5) Concentrations: August 2005 Updated Report Regarding Second-Generation and New PM 10-2.5 Samplers 09/18/2006
VANDERPOOL, R. W., T. HANLEY, F. DIMMICK, E. T. HUNIKE, P. A. SOLOMON, F. F. MCELROY, R. MURDOCH, AND S. NATARAJAN. Multi-Site Evaluations of Candidate Methodologies for Determining Coarse Particulate (PM 10-2.5) Concentrations: August 2005 Updated Report Regarding Second-Generation and New PM 10-2.5 Samplers. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-06/093 (NTIS PB2006-115765), 2006.
Abstract: Multi-site field studies were conducted to evaluate the performance of sampling methods for measuring the coarse fraction of PM10 (PM10 2.5) in ambient air. The field studies involved the use of both time-integrated filter-based and direct continuous methods. Despite operational problems encountered with some of the instruments during these field intensives, overall measurement results were encouraging and the instrument manufacturers are continuing to improve the reliability of the coarse mode samplers.

PUBLISHED REPORT EXPOSURE RELATED DOSE ESTIMATING MODEL ( ERDEM ) A PHYSIOLOGICALLY-BASED PHARMACOKINETIC AND PHARMACODYNAMIC ( PBPK/PD ) MODEL FOR ASSESSING HUMAN EXPOSURE AND RISK 06/28/2006
BLANCATO, J. N., F. W. POWER, R. N. BROWN, AND C. C. DARY. EXPOSURE RELATED DOSE ESTIMATING MODEL ( ERDEM ) A PHYSIOLOGICALLY-BASED PHARMACOKINETIC AND PHARMACODYNAMIC ( PBPK/PD ) MODEL FOR ASSESSING HUMAN EXPOSURE AND RISK. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-06/061 (NTIS PB2006-114712), 2006.
Abstract: The Exposure Related Dose Estimating Model (ERDEM) is a PBPK/PD modeling system that was developed by EPA's National Exposure Research Laboratory (NERL). The ERDEM framework provides the flexibility either to use existing models and to build new PBPK and PBPK/PD models to address specific science questions. Over the past several years, ERDEM has been enhanced to improve ease of operation and to provide additional modeling capabilities. With these enhancements, ERDEM has been applied to a variety of chemicals as part of the regulatory risk assessment process. Applications for malathion and N- methyl carbamate were presented to and peer-reviewed by the FIFRA Scientific Advisory Panel.

PUBLISHED REPORT Estimating Contributions of Outdoor Fine Particles to Indoor Concentrations and Personal Exposures: Effects of Household Characteristics and Personal Activities 03/02/2006
WALLACE, L. A., R. W. WILLIAMS, J. SUGGS, AND P. A. JONES. Estimating Contributions of Outdoor Fine Particles to Indoor Concentrations and Personal Exposures: Effects of Household Characteristics and Personal Activities. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-06/023 (NTIS PB2006-113533), 2006.
Abstract: A study of personal, indoor, and outdoor exposure to PM2.5 and associated elements has been carried out for 37 residents of the Research Triangle Park area in North Carolina. Participants were monitored for 7 consecutive days in each of four seasons. One goal of the study was to estimate the contribution of outdoor PM2.5 to indoor concentrations and personal exposures on an individual basis. This contribution depends on the infiltration factor Finf, the fraction of outdoor PM2.5 remaining airborne after penetrating indoors. Relying on previous studies suggesting that sulfur has few indoor sources, we can estimate Finf for each house based on indoor/outdoor sulfur ratios. Since Finf depends on air exchange rates, we can also calculate the value by regressing the observed indoor/outdoor sulfur ratios on the measured air exchange rates. The two approaches are not completely independent but give excellent agreement (R2 = 0.96-0.99) in estimating the average infiltration factor for each house, thereby validating the air exchange rate measurements and providing considerable confidence in the reliability of Finf estimates. These estimates range from 0.26 to 0.89. Using the daily estimated infiltration factor for each house, we calculate the contribution of outdoor PM2.5 to indoor air concentrations, both for the full year and for the four seasons. We show that in summer when air conditioners were in use, the contribution of outdoor PM2.5 to indoor concentrations was at its lowest (averaging 0.50) for most homes, whereas the average infiltration factor for the other three seasons was 0.62-0.63. The indoor-generated contributions to indoor PM2.5 had a wider range (0-33 µg/m3) than the outdoor contributions (5-22 µg/m3). We then regress the calculated outdoor PM2.5 contribution to indoor air concentrations on measured residential outdoor concentrations. The regressions have moderately high R2 values (range 0.39-0.93), although we present evidence that these values should be treated as upper bounds rather than best estimates.
A second goal was to calculate the "outdoor exposure factor" Fpex, the fraction of outdoor PM2.5 contributing to personal exposure. This can be done directly using the ratio of personal/outdoor sulfur measurements, or indirectly using a model depending on the fraction of time spent indoors. The direct measurements result in an estimate of 0.54 for the mean outdoor exposure factor, whereas the model predicts a mean value of 0.63. We find that the time-weighted model adds no value to our estimate of Fpex and discuss the possible reasons for this. Using the direct estimates of Fpex based on the sulfur ratios, we calculate the contribution of outdoor PM2.5 to personal exposure. The range of outdoor contributions to personal exposure (6-18 µg/m3) is much smaller than the range of indoor contributions (6-34 µg/m3). We regress this contribution on measured outdoor PM2.5. This regression is desired by epidemiologists attempting to relate health effects to outdoor particle concentrations, since it shows the strength of the relationship between exposure to particles of outdoor origin and the outdoor concentrations. The regressions again have moderately high R2 values (range 0.19-0.88), although again we show that these values should be treated as upper bounds.

A third but somewhat subsidiary goal was to estimate two remaining parameters that affect Finf: the penetration coefficient P and the deposition rate k, where these parameters are assumed to refer to sulfur and particles in the same size range as sulfur. We use two approaches, which, however, are not completely independent. Both involve using the indoor/outdoor sulfur ratio (or its inverse) and the air exchange rate (or its inverse). While the two approaches generally agree well on predicting P and k for individual homes, each includes some nonphysical estimates (e.g., P >1). Also, many of the estimates for k are not significantly different from zero. We conclude that the lack of an independent method for estimating P and k results in our inability to validate these estimates for individual homes. On the other hand, the overall estimate of the average P (0.81-0.85) and k (0.22-0.23 h-1) for all homes may be more stable.

As a result of our ability to split indoor and personal exposures into indoor-generated and outdoor-generated particles, we were able to run regressions on these variables as well. This allows a better estimate of the impact of air exchange rates, since air exchange operates in opposite directions for these two variables. The results show that increases in air exchange (either measured or approximated by questionnaire responses referring to open windows) significantly affect each of these variables in the expected direction (increasing the impact of outdoor-generated particles, decreasing the impact of indoor-generated particles).

A fourth and final goal of this analysis was to identify household characteristics and personal activities that may affect exposure. A number of multiple regressions were performed on the personal, indoor, and outdoor PM2.5 and sulfur concentrations. A simple regression of indoor PM2.5 on outdoor PM2.5 resulted in an R2 value of only 9%; the multiple regression improved the R2 to 42% (using the outdoor monitors near the home) and 43% (using the central-site monitor). Important variables affecting indoor air PM2.5 concentrations included smoking and cooking, variables often found in other studies. The number of persons in the household contributed to PM2.5 and this has also been noted before. However, burned food, use of a kitchen exhaust fan, number of pilot lights, and duration of candle use were also important contributors, and these have not generally been noted in other studies.

PUBLISHED REPORT Relationships Between Questionnaire Responses and Children's Pesticide Exposure Measurements 01/19/2006
THOMPSON, C. B., L. S. HARRISON, R. FENSKE, G. L. ROBERTSON, AND S. C. HERN. Relationships Between Questionnaire Responses and Children's Pesticide Exposure Measurements. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-05/092 (NTIS PB2006-102459), 2005.
Abstract: The objective of this project is to identify questions that indicate a higher likelihood of predicting a child's level of exposure to pesticides as input to future study designs.

 

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