May 2011

EPA/600/R-10/075A

Integrated Science Assessment 

for Lead

National Center for Environmental Assessment-RTP Division

Office of Research and Development

U.S. Environmental Protection Agency

Research Triangle Park, NC
May 2011 ii DRAFT – DO NOT CITE OR QUOTE

Disclaimer

This document is the first external review draft for review purposes only and does not constitute 

U.S. Environmental Protection Agency policy. Mention of trade names or commercial products does 

not constitute endorsement or recommendation for use.
May 2011 iii DRAFT – DO NOT CITE OR QUOTE

Contents

Lead Project Team____________________________________________________________________________________ iv

Authors, Contributors, and Reviewers ___________________________________________________________________ vi

Clean Air Scientific Advisory Committee Lead NAAQS Review Panel_________________________________________ xi

Acronyms and Abbreviations __________________________________________________________________________ xiii
May 2011 iv DRAFT – DO NOT CITE OR QUOTE

Lead Project Team 

Executive Direction

Dr. John Vandenberg (Director)—National Center for Environmental Assessment-RTP Division, 

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

Park, NC

Ms. Debra Walsh (Deputy Director)—National Center for Environmental Assessment-RTP Division, 

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

Park, NC

Dr. Mary Ross (Branch Chief)—National Center for Environmental Assessment, Office of Research 

and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Doug Johns (Acting Branch Chief)—National Center for Environmental Assessment, Office of 

Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Scientific Staff

Dr. Ellen Kirrane (Pb Team Leader)—National Center for Environmental Assessment, Office of 

Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. James Brown—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Mr. Allen Davis—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Jean-Jacques Dubois—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Tara Greaver—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Erin Hines—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Dennis Kotchmar—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Meredith Lassiter—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Stephen McDow—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC
May 2011 v DRAFT – DO NOT CITE OR QUOTE

Dr. Qingyu Meng—Oak Ridge Institute for Science and Education, National Center for 

Environmental Assessment, Office of Research and Development, U.S. Environmental Protection 

Agency, Research Triangle Park, NC

Dr. Elizabeth Oesterling Owens—National Center for Environmental Assessment, Office of 

Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Molini Patel—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Jennifer Richmond-Bryant—National Center for Environmental Assessment, Office of Research 

and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Lindsay Stanek—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. David Svendsgaard—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Lisa Vinikoor-Imler—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Technical Support Staff

Mr. Kenneth J. Breito–Senior Environmental Employment Program, National Center for 

Environmental Assessment, Office of Research and Development, U.S. Environmental Protection 

Agency, Research Triangle Park, NC 

Ms. Ellen Lorang—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Mr. J. Sawyer Lucy–Student Services Authority, National Center for Environmental Assessment, 

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

Park, NC

Ms. Deborah Wales—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Mr. Richard N. Wilson–National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Ms. Barbara Wright—Senior Environmental Employment Program, National Center for 

Environmental Assessment, Office of Research and Development, U.S. Environmental Protection 

Agency, Research Triangle Park, NC
May 2011 vi DRAFT – DO NOT CITE OR QUOTE

Authors, Contributors, and Reviewers

Authors

Dr. Ellen Kirrane (Pb Team Leader)—National Center for Environmental Assessment, Office of

Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Robyn Blain— Energy, Environment and Transportation, Environmental Science & Policy, ICF 

International, Lexington, MA

Dr. James Brown—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Mr. Allen Davis—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC 

Dr. Gary Diamond—Syracuse Research Corporation, Akron, NY 

Dr. Rodney Dietert—Cornell University College of Veterinary Medicine, Veterinary Medical Center, 

Ithaca, NY

Dr. Jean-Jacques Dubois—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Anne Fairbrother—Exponent, Inc., Bellevue, WA

Dr. Jay Gandy—Department of Environmental and Occupational Health, University of Arkansas for 

Medical Sciences, Little Rock, AR

Dr. Harvey Gonick—David Geffen School of Medicine, University of California-Los Angeles, Los 

Angeles, CA

Dr. Margaret Graham—School of Geosciences, University of Edinburgh, Edinburgh, Scotland

Dr. Tara Greaver—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Erin Hines—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Dennis Kotchmar—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Meredith Lassiter—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Stephen McDow—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC
May 2011 vii DRAFT – DO NOT CITE OR QUOTE

Dr. Qingyu Meng—Oak Ridge Institute for Science and Education, National Center for 

Environmental Assessment, Office of Research and Development, U.S. Environmental Protection 

Agency, Research Triangle Park, NC

Dr. Bill Mendez—Energy, Environment and Transportation, Environmental Science & Policy, ICF 

International, Fairfax, VA

Dr. Howard Mielke—Center for Bioenvironmental Research, Tulane/Xavier Universities, New 

Orleans, LA

Ms. Chandrika Moudgal— Energy, Environment and Transportation, Environmental Science & 

Policy, ICF International, Dublin, CA

Dr. Elizabeth Oesterling Owens—National Center for Environmental Assessment, Office of 

Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Katherine Palmquist—Exponent, Inc., Bellevue, WA

Dr. Molini Patel—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Jennifer Richmond-Bryant—National Center for Environmental Assessment, Office of Research 

and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Stephen Rothenberg—National Institute of Public Health, Cuernavaca, Morelos, Mexico

Dr. MaryJane Selgrade—Energy, Environment and Transportation, Environmental Science & Policy, 

ICF International, RTP, NC

Dr. Lindsay Stanek—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. David Svendsgaard—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Lisa Vinikoor-Imler—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Virginia Weaver—Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 

Dr. Marc Weisskopf—Department of Environmental Health and Department of Epidemiology, 

Harvard School of Public Health, Harvard University, Boston, Massachusetts 

Dr. John Pierce Wise, Sr.—Maine Center for Toxicology and Environmental Health, Department of 

Applied Medical Sciences, Portland, ME 

Dr. Rosalind Wright—Harvard Medical School and School of Public Health, Harvard University, 

Boston, MA

Dr. Robert Wright—Harvard Medical School and School of Public Health, Harvard University, 

Boston, MA 
May 2011 viii DRAFT – DO NOT CITE OR QUOTE

Contributors

Mr. Brian Adams—Oak Ridge Institute for Science and Education, National Center for 

Environmental Assessment, Office of Research and Development, U.S. Environmental Protection 

Agency, Research Triangle Park, NC

Dr. Halil Cakir—Oak Ridge Institute for Science and Education, National Center for Environmental 

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

Triangle Park, NC

Ms. Ye Cao—Oak Ridge Institute for Science and Education, National Center for Environmental 

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

Triangle Park, NC

Mr. Josh Drukenbrod, Office of Air Quality Planning and Standards, Office of Air and Radiation, 

U.S. Environmental Protection Agency, RTP, NC

Ms. Katelyn Hausman—Department of Epidmiology, Gillings School of Global Public Health, 

University of North Carolina, Chapel Hill, NC 

Ms. Katie Shumake—Oak Ridge Institute for Science and Education, National Center for 

Environmental Assessment, Office of Research and Development, U.S. Environmental Protection 

Agency, Research Triangle Park, NC

Ms. Lauren Tuttle—Oak Ridge Institute for Science and Education, National Center for 

Environmental Assessment, Office of Research and Development, U.S. Environmental Protection 

Agency, Research Triangle Park, NC

Ms. Brianna Young—Oak Ridge Institute for Science and Education, National Center for 

Environmental Assessment, Office of Research and Development, U.S. Environmental Protection 

Agency, Research Triangle Park, NC

Reviewers

Dr. David Buchwalter—Department of Toxicology, North Carolina State University, Raleigh, NC

Mr. Kevin Cavender—Office of Air Quality Planning and Standards, Office of Air and Radiation, 

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

Dr. David DeMarini—National Health and Environmental Effects Research Laboratory, Office of 

Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Pam Factor-Litvak—Department of Epidemiology, Mailman School of Public Health, New York, 

NY

Dr. Gabriel Filippelli—Department of Earth Sciences, Indiana University-Purdue University, 

Indianapolis, IN

Dr. Andrew Friedland—Environmental Studies Program, Darmouth College, Hanover, NH
May 2011 ix DRAFT – DO NOT CITE OR QUOTE

Dr. Barbara Glenn—National Center for Environmental Assessment, Office of Research and 

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

Dr. Jeff Herrick—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Marion Hoyer—Office of Transportation and Air Quality, Office of Air and Radiation, 

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

Dr. Douglas Johns—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Thomas Luben—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Karen Martin—Office of Air Quality Planning and Standards, Office of Air and Radiation, 

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

Ms. Connie Meacham—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Marie Lynn Miranda—Environmental Sciences and Policy, Nicholas School of the Environment, 

Duke University, Durham, NC

Dr. Deirdre Murphy—Office of Air Quality Planning and Standards, Office of Air and Radiation, 

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

Dr. Paul Mushak—PB Associates, Durham NC

Dr. Kris Novak—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Mr. David Orlin—Air and Radiation Law Office, Office of General Counsel, U.S. Environmental 

Protection Agency, Washington, DC

Dr. Pradeep Rajan—Office of Air Quality Planning and Standards, Office of Air and Radiation, 

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

Ms. Joanne Rice—Office of Air Quality Planning and Standards, Office of Air and Radiation, 

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

Dr. Mary Ross—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Joel Schwartz—Department of Environmental Health, Harvard School of Public Health, Boston, 

MA

Mr. Jason Sacks—National Center for Environmental Assessment, Office of Research and 

Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Jay Turner—Environmental and Chemical Engineering Department, Washington University, St. 

Louis, MO
May 2011 x DRAFT – DO NOT CITE OR QUOTE

Dr. John Vandenberg—National Center for Environmental Assessment-RTP Division, Office of 

Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Nosratola Vaziri—Division of Nephrology and Hypertension, School of Medicine, University of 

California, Irvine

Ms. Debra Walsh—National Center for Environmental Assessment-RTP Division, Office of 

Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC

Dr. Nasser Zawia—Department of Biomedical and Pharmaceutical Sciences, University of Rhode 

Island
May 2011 xi DRAFT – DO NOT CITE OR QUOTE

Clean Air Scientific Advisory Committee 

Lead NAAQS Review Panel

Chair of the Environmental Protection Agency’s Clean Air Scientific Advisory Committee

Dr. Jonathan M. Samet*, Department of Preventive Medicine at the Keck School of Medicine, and 

Director of the Institute for Global Health at the University of Southern California, Los Angeles, CA

Chair of the Lead Review Panel

Dr. Christopher H. Frey*, North Carolina State University, Raleigh, NC

Members

Dr. George A. Allen*, Northeast States for Coordinated Air Use Management (NESCAUM), Boston, 

MA

Dr. Herbert Allen, University of Delaware, Newark, DE

Dr. Richard Canfield, Cornel University, Ithaca, NY

Dr. Deborah Cory-Slechta, University of Rochester, Rochester, NY

Dr. Cliff Davidson, Syracuse University, Syracuse, NY

Dr. Philip E. Goodrum, Environmental Resources Management (ERM), Dewitt, NY

Dr. Sean Hays, Summit Toxicology, Allenspark, CO

Dr. Philip Hopke, Clarkson University, Potsdam, NY

Dr. Susan Korrick, Harvard Medical School, Boston, MA

Dr. Michael Kosnett, University of Colorado Health Sciences Center, Denver, CO

Dr. Roman Lanno, Ohio State University, Columbus, OH

Dr. Richard L. Poirot, Vermont Agency of Natural Resources, Waterbury, VT

Dr. Joel Pounds, Battelle-Pacific Northwest National Laboratory, Richland, WA

Dr. Michael Rabinowitz, Harvard University, Newport, RI

Dr. William Stubblefield, Oregon State University, Corvallis, OR

Dr. Ian von Lindern, TerraGraphics Environmental Engineering, Inc., Moscow, ID

Dr. Gail Wasserman, Columbia University, New York, NY
May 2011 xii DRAFT – DO NOT CITE OR QUOTE

Dr. Michael Weitzman, New York University School of Medicine, New York, NY

* Members of the statutory Clean Air Scientific Advisory Committee (CASAC) appointed by the 

EPA Administrator 

Science Advisory Board Staff 

Mr. Aaron Yeow, Designated Federal Officer, Office of Administration, Science Advisory Board 

Staff Office, U.S. Environmental Protection Agency, Washington, DC 20004. Phone: 202-564-2050, 

Email: yeow.aaron@epa.gov
May 2011 xiii DRAFT – DO NOT CITE OR QUOTE

Acronyms and Abbreviations

α alpha

αT the extent of DNA denaturation per cell

Å Ångström (10-10 meter)

AA African American; arachidonic acid, atomic absorption

AALM All Ages Lead Model

AAS atomic absorption (spectrophotometry, spectrometry, spectroscopy)

Ab amyloid-beta peptide 

ABL atmospheric boundary layer

ACE angiotensin converting enzyme

ACh acetylcholine

ACP acid phosphatase

ACR acute to chronic ratio

Acyl-CoA acyl-coenzyme A

AD axial diffusivity

ADHD attention deficit hyperactivity disorder

ADP adenosine diphosphate

AE anion exchanger

AF absorbed fraction; absorption fraction

A/G albumin/globulin

Ag silver

A-horizon topsoil horizon (surface soil)

AKI acute kidney injury

Al aluminum

ALA aminolevulinic acid 

ALAD aminolevulinic acid dehydratase; aminolevulinic acid dehydrogenase; 

aminolevulinate dehydratase; δ-aminolevulinic acid dehydratase

ALAD 1-1 aminolevulinate delta-dehydratase 1-1

ALAD-2 aminolevulinate delta-dehydratase-2

ALD aldehyde dehydrogenase

ALM Adult Lead Methodology

ALP alkaline phosphatase

ALT alanine aminotransferase

AM Alveolar macrophages

AMF arbuscular mycorrhizal fungi

AMP adenosine monophosphate

ANC acid neutralizing capacity; absolute neutrophil counts

ANF atrial natriuretic factor

AngII renal angiotensin II

ANOVA analysis of variance

ANPR advance notice of proposed rulemaking

AP-1 activator protein-1

ApaI polymorphism of the VDR in humans

APC antigen-presenting cell

APOE Apolipoprotein E 

APRT adenine phosphoribosyltransferase

AQCD Air Quality Criteria Document

AQS (U.S. EPA) Air Quality System (database)

As arsenic
May 2011 xiv DRAFT – DO NOT CITE OR QUOTE

AST aspartate aminotransferase 

ASV anode stripping voltammetry

ATLD ataxia-telangiectasia-like disorder

ATOFMS aerosol time-of-flight mass spectrometry

ATP adenosine-triphosphate

ATPase adenosine triphosphatase; adenosine triphosphate synthase

ATSDR Agency for Toxic Substances and Disease Research

Au gold

avg average

AVS acid-volitile sulfides

a-wave initial negative deflection in the electroretinogram

AWQC Ambient Water Quality Criteria

β Beta; Beta coefficient; regression coefficient; standardized coefficient

3β-HSD 3-beta-hydroxysteroid dehydrogenase

17β-HSD 17-beta-hydroxysteroid dehydrogenase

Ba barium

BAF bioaccumulation factors

BAL 2,3-dimercaptopropanol 

BASC Behavior Assessment System for Children

BASC-PRS Behavior Assessment System for Children-Parent Ratings Scale

BASC-TRS Behavior Assessment System for Children-Teacher Rating Scale

BCB blood cerebrospinal fluid barrier

B-cell Bone marrow-derived lymphocytes, B lymphocyte

BCF bioconcentration factors

Bcl-x member of the B-cell lymphoma-2 protein family

Bcl-xl B-cell lymphoma-extra large

B-horizon subsoil horizon

bio biological

Bi2S3 bismuth (III) sulfide

BK biokinetics

BLM biotic ligand model

BMD benchmark dose; bone mineral density

BMDL benchmark dose limit

BMI body mass index

BMP bone morphogenetic protein

BMS Baltimore Memory Study 

BMW battery manufacturing workers

BP blood pressure

BR bronchial responsiveness

BrdU bromo-2’-deoxyuridine

8-Br-GMPc 8-bromo-cyclic guanosine monophosphate

Bs-horizon subsoil horizon with accumulation of sesquioxides

BSI Brief Symptom Inventory 

BSID-II Bayley Scale for Infant Development-II

BsmI polymorphism of the VDR in humans

Bt20 birth to 20 cohort

BUN blood urea nitrogen

bw body weight

b-wave initial positive deflection in the electroretinogram

C carbon; Celsius; soil or dry sediment Pb concentration; Caucasian; 

Cysteine

Ca calcium
May 2011 xv DRAFT – DO NOT CITE OR QUOTE

Ca2+ calcium ion

CAA Clean Air Act

CaBP calcium binding protein

CaCl2 calcium chloride

CaCO3 calcium carbonate; calcite

CaEDTA calcium ethylenediaminetetraacetic acid

CaMKII calmodulin-dependent protein kinase II

cAMP cyclic adenosine monophosphate

CASAC Clean Air Scientific Advisory Committee

CASM Comprehensive Aquatic Systems Model

CaSO4 calcium sulfate

CaSO4.2H2O gypsum

CAT catalase

CBLI cumulative blood lead index

CBSA core based statistical area

CD cluster of differentiation

Cd cadmium

Cd(II) cadmium (II)

Cd2+ cadmium ion

CD3+ T lymphocyte

CD4+ T helper cell

CDC Centers for Disease Control

CEA carcinoembryonic antigen

CEC cation exchange capacity

cent central

cert. certiorari

cf correction factor; latin abbreviation for conferre (used as "compared 

with)

CFL contanst flux layer

CFR Code of Federal Regulations

cGMP cyclic guanosine monophosphate

ChAT chlorine acetyltranferase

CHD coronary heart disease

CHL Chinese hamster lung

CHO Chinese hamster ovary cell line

C-horizon soil horizon under A- and B- horizons, may contain lumps or shelves 

of rock and parent material

CHV79 Chinese hamster lung cell line

CI confidence interval

Cir. circuit

CKD chronic kidney disease

CKD-EPI Chronic Kidney Disease Epidemiology Collaboration

CL confidence limit

Cl chlorine

Cl- chlorine ion

Cl2 molecular chlorine

CLACE 5 fifth Cloud and Aerosol Characterization Experiment in the Free 

Troposphere campaign

CLS Cincinnati Lead Study 

CO carbon monoxide

CO2 carbon dioxide 

CO3

2- carbonate ion
May 2011 xvi DRAFT – DO NOT CITE OR QUOTE

Co cobalt

CoA coenzyme A

COD coefficient of difference

Coeff coefficient

COMP aT the percentage of sperm with increased sensitivity to DNA

denaturation

Con control

Conc. concentration

Cong. congress

Corr correlation

COX cyclooxygenase; cytochrome oxidase subunits

COX-2 cyclooxygenase-2

cPLA2 cytosolic phopholipidase A2

CPRS-R Conners' Parent Rating Scale-Revised

Cr chromium; creatine

Cr III chromium III

CRAC Ca2+ release activated calcium

CRACI calcium release activated calcium influx

CREB cyclic adenosinemonophosphate (cAMP) response element-binding

CRP C-reactive protein

CSF colony-stimulating factor

CSN Chemical Speciation Network

CT zinc-adequate control

Cu copper

Cu(II) copper (II)

CV coefficient of variation

CVD cardiovasicular disease

CYP cytochrome

CYP 1A1, Cyp1A1 cytochrome P450 family 1 member A1

CYP 1A2, Cyp1A2 cytochrome P450 family 1 member A2

CYP P450 cytochrome P450

Δ delta, difference, change

Δ5-3β-HSD delta-5-3-beta-hydroxysteroid dehydrogenase

δ-ALA 5-aminolevulinic acid; delta-aminolevulinic acid 

δ-ALAD delta-aminolevulinic acid dehydratase

D2, D3 dopamine receptors

D50 size at 50% efficiency

d day(s); depth

db, dB decibel

DbH dopamine beta-hyrdoxylase 

DBP diastolic blood pressure

dep dependent

dev. deviation

DEX exogenous dexamethasone

DG degenerate gyrus 

2-dG 2-deoxyguanosine 

DHAA dehydroascorbate

diff differentiation

DIT developmental immunotoxicity

DMPS 2,3-dimercaptopropane-l-sulfonic acid 

DMSA dimercaptosuccinic acid

DMSO dimethyl sulfoxide
May 2011 xvii DRAFT – DO NOT CITE OR QUOTE

DNA deoxyribonucleic acid

DoAD developmental origins of adult disease 

DOC dissolved organic carbon

DOM dissolved organic matter

DP-109 metal chelator

DP-460 metal chelator

DR diet-restricted

DRD4 dopamine 4 receptor 

DRD4.7 dopamine 4 receptor repeat alleles

DRUM Davis Rotating Unit for Monitoring

D-serine neuronal signal

DSM-IV Diagnostic Statistical Manual-IV

DTH delayed-type hypersensitivity

DTPA diethylene triamine pentaacetic acid; techetium-diethylenetriaminepentaacetic acid

E east; expression for exposure 

E2 estradiol

e exponential function

EC endothelial cell

EC10 effect concentration for 10% of test population

EC20 effect concentration for 20% of test population

EC50 effect concentration for 50% of test population

ECG electrocardiography; electrocardiogram

ECOD 7-ethoxycoumarin-o-deethylase

Eco-SSLs ecological soil screening levels

ED10 effect dose for 10% of population

EDTA ethylenediaminetetraacetic acid

EFS electrical field stimulus

EGF epidermal growth factor 

EGFR epidermal growth factor receptor

eGFR estimated glomerular filtration rate

Eh electrochemical potential

E-horizon soil horizon with eluviated or leached of mineral and/or organic 

content

EI-MS electron impact ionization mass spectrometry

eNOS endothelial nitric oxide synthase

EOG end-of-grade

EPA U.S. Environmental Protection Agency

EPT ephemeroptera, plecoptera, trichoptera

ER endoplasmic reticulum

Erg-1 ether-a-go-go related gene 

ERG electroretinogram

ERK extracellular signal regulated kinase

ERK1/2 extracellular signal-regulated kinases 1 and 2

EROD 7-ethoxyresorufin-o-deethylase

ESCA electron spectroscopy for chemical analysis

ESI-MS electrospray ionization mass spectrometry

ESRD end stage renal disease

ET endothelin 

ET-1 vasoconstrictor endothelin-1 

ETA-type receptors endothelin type A receptors

EU European Union
May 2011 xviii DRAFT – DO NOT CITE OR QUOTE

EURO European emission standard

eV electronvolts

EXAFS X-ray absorption fine structure spectroscopy

F0 filial 0 generation

F1 first offspring generation

F2 second offspring generation

FAA Federal Aviation Agency

FAI free androgen index

FAS apoptosis stimulating fragment

Fas-L apoptosis stimulating fragment ligand

Fe iron

Fe(III) iron III

FEM Federal equivalence method

FEV1 forced expiratory volume in 1 second

FI fixed interval 

FI-Ext fixed interval with extinction

Fl fluoride

FokI polymorphism of the VDR in humans

FR Federal Register (Notice)

FrA fractional anisotropy 

FR-FI fixed ratio-fixed interval 

FRM Federal reference method

FSH follicle-stimulating hormone

FSIQ full scale intelligence quotient (IQ)

FT3 free triodothyronine

FT4 free thyroxine 

G pregnancy; guanine

G2 gap 2 Phase

g, mg, kg, μg, ng, pg gram(s), milligram(s), microgram(s), kilogram(s), nanogram(s), 

picogram(s)

G93A mouse model

GABA γ-aminobutyric acid; gamma aminobutyric acid

GABAergic gamma aminobutyric acid-ergic

GAD generalized anxiety disorder

GC gas chromatography

G-CSF granulocyte colony-stimulating factor

GD gestational day

GEE generalized estimating equations

GFAAS graphite furnace atomic absorption spectrometry

GFAP glial fibrillary acidic protein

GFR glomerular filtration rate

GGT gamma-glutamyl transpeptidase

GH growth hormone

GI gastrointestinal

GIS Geographic Information System

G+L pregnancy plus lactation

GLE gestationally-lead exposed 

GM geometric mean

GMR geometric mean blood lead ratio

GnRH gonadotropin-releasing hormone

G6PD glucose-6-phosphate dehydrogenase

GPEI glutathione transferase P (GST-P) enhancer I
May 2011 xix DRAFT – DO NOT CITE OR QUOTE

GPT glutamate pyruvate transaminase

GPx glutathione peroxidase

GPX1 gene encoding for glutathione peroxidase 1

GR glutathione reductase

GRP78 glucose-regulated protein 78

GRP94 glucose-regulated protein 94

Grp glucose-regulated protein

GSD geometric standard deviation

GSH glutathione

GSSG glutathione disulfide

GST glutathione S-transferase

GSTM1 glutathione S-transferase Mu 1 

GST-P glutathione transferase P

GTP guanosine-5'-triphosphate; guanine triphosphate 

H hydrogen

H+ hydrogen ion

h hour(s)

ha hectare

HAD hydroxyalkenals

Hb hemoglobin

HC5 acute toxicity hazardous concentration for 5% of species

HC10 acute toxicity hazardous concentration for 10% of species

HCl hydrochloric acid

HCO3

- bicarbonate; hydrogen carbonate

Hct hematocrit

HDL high-density lipoprotein

HF hydrogen fluoride

HFE hemochromatosis gene

HFE C282Y hemochromatosis gene with C282Y mutation

HFE H63D hemochromatosis gene with H63D mutation

Hg mercury

HgCl2 mercury(II) chloride

5-HIAA 5-hydroxyindoleacetic acid

HIV human immunodeficiency virus

HLA-DRB human leukocyte antigen genes

HMEC human dermal microvascular endothelial cells

HMGR 3-hydroxy-3-methylglutaryl-CoA reductase

HMOX-1 heme oxygenase-1

HNO3 nitric acid

HO-1 heme oxygenase; heme oxidase-1 

H2O water

H2O2 hydrogen peroxide

HOME Home Observation for Measurement of the Environment

HPA hypothalamic-pituitary-adrenal

HPb, h-Pb high lead

HPG hypothalamic-pituitary-gonadal

HPLC high-performance liquid chromatography

HPRT hypoxanthine-guanine phosphoribosyltransferase

HPT hyperparathyroidism; hypothalamic-pituitary-thyroid 

HR heart rate; hazard ratio

HRV heart rate variability

hsp heat shock proteins
May 2011 xx DRAFT – DO NOT CITE OR QUOTE

5HT serotonin

5-HT 5-hydroxytryptamine

5-HT2B 5-hydroxytryptamine receptor 2B

hTERT telomerase reverse transcriptase

HVA homovanillic acid

I interstate

IARC International Agency for Research on Cancer

IC50 half maximal inhibitory concentration

ICAP inductively coupled argon plasma

ICP-AES inductively coupled plasma atomic emission spectroscopy

ICPMS, ICP-MS inductively coupled plasma mass spectrometry

ICR imprinting control region

ICRP International Commission on Radiological Protection

ID identification

IDA iron-deficiency anemia 

IDE insulin-degrading enzyme 

IEPA Illinois Environmental Protection Agency

IEUBK Integrated Exposure Uptake Biokinetic

IFN-γ interferon-gamma

Ig immunoglobulin

IgA immunoglobulin A

IgE immunoglobulin E

IGF-1 insulin-like growth factor 1

IgG immunoglobulin G

IgM immunoglobulin M

IHD ischemic heart disease

IL interleukin

IL-1β interleukin-1 Beta

IL-2 interleukin-2

IL-4 interleukin-4

IL-5 interleukin-5

IL-6 interleukin-6

IL-8 interleukin-8

IL-10 interleukin-10

IL-12 interleukin-12

IMPROVE Interagency Monitoring of Protected Visual Environment

IMT intimal medial thickening

INL inner neuroblastic layers of the retina 

iNOS inducible nitric oxide synthase

i.p. intraperitoneal (route)

IQ intelligence quotient

IQR interquartile range

IRE1 inositol-requiring enzyme-1

ISA Integrated Science Assessment

ISF intake slope factor

ISL inertial sublayer

ISO International Standards Organization

i.v. intravenous

IVBA in vitro bioaccessibility

IVF in vitro fertilization

JNK jun N-terminal kinase

K Kelvin; potassium; resupsension factor
May 2011 xxi DRAFT – DO NOT CITE OR QUOTE

K+ potassium ion

K0.5 concentration of free metal giving half maximal metal-dependent 

release

KART Karters of American Racing Triad

Kd dissociation constant

Kd partition coefficient; ratio of the metal concentration in soil to that in 

soil solution

kDa, kD kiloDalton

KEDI-WISC Korean Educational Development Institute-Wechsler Intelligence 

Scale for Children

6-keto-PGF1α 6-keto-prostaglandin F1α (vasodilatory prostaglandin)

keV kiloelectron volt

Ki-67 antigen, cell cycle and tumor growth marker

Kim-1 kidney injury molecule-1

Kinder-KITAP Kinder-Testbatterie zur Aufmerksamkeitsprüfung für Kinder

K-ras specific protooncogene

Λ lambda; resuspension rate

L length

L, mL, dL liter(s), milliliter(s), deciliter(s)

LA-ICP-MS laser ablation inductively coupled plasma mass spectrometry

LC50 lethal concentration (at which 50% of exposed organisms die)

LD50 lethal dose (at which 50% of exposed organisms die)

LDH lactate dehydrogenase

LDL low-density lipoproteins

LFH-horizons organic soil horizons located above well-drained surface soil 

LF/HF low frequency to high frequency ratio

LH luteinizing hormone

LHRH luteinizing hormone releasing hormone

LINE long interspersed nuclear element

LINE-1 long interspersed nucleotide elements-1

LLNA local lymph node assay 

ln natural logarithm

L-NAME L-NG-nitroarginine methyl ester

L-NOARG L-nitroarginine

LOEC lowest-observed-effect concentration

log logarithm

LPb low lead

LPS lipopolysaccharide

LSO lateral superior olive 

M metal

M, mM, μM, nM Molar, milliMolar, microMolar, nanoMolar

m, cm, mm, μm, nm, km meter(s), centimeter(s), millimeter(s), 

micrometer(s), nanometer(s), kilometer(s)

MAP mean arterial pressure

MAPK mitogen-activated protein kinase(s), MAP kinase

MATC maximum acceptable toxicant concentration

max maximum, maxima

MBP myelin basic protein

MCH mean corpuscular hemoglobin

MCHC mean corpuscular hemoglobin concentration

MchDMSA mono-cyclohexyl dimercaptosuccinic acid

MCL maximum containment level

MCP-1 monocyte chemotactic protein-1
May 2011 xxii DRAFT – DO NOT CITE OR QUOTE

MCV mean corpuscular volume

MD mean diffusivity

MDA malondialdehyde

MDD major depressive disorder 

MDI Mental Development Index

MDL method detection limit

MDRD Modification of Diet in Kidney Disease 

Med, med median

MEK1 dual specificity mitogen-activated protein kinase 1

MEK2 dual specificity mitogen-activated protein kinase 2

Mg magnesium

Mg2+ magnesium ion

MHC major histocompatibility complex

MI myocardial infarction, "heart attack"; myocardial ischemia

mI myoinositol

min minimum; minima; minute(s)

MKK1/2 MAPK kinase 1 and 2

ML mixed layer

MMAD mass median aerodynamic diameter

MMF mycophenolate mofetil

mmHg millimeters of mercury

mmol, μmol, nmol millimole(s), micromole(s), nanomole(s)

MN micronuclei formation; mononuclear 

Mn manganese

MNE micronucleated erythrocytes per thousand

MnO2 manganese dioxide

Mo molybdenum

mo month(s)

MOUDI multi-orifice uniform deposit impactor

MPb, m-Pb moderate lead

MPO myeloperoxidase

MRI magnetic resonance imaging

mRNA messenger ribonucleic acid

MRS magnetic resonance spectroscopy

MS maternal stress

MSC mesenchymal cell

MSWI municipal solid waste incineration

Mt metallothionein

MTHFR methylenetetrahydrofolate reductase 

MTP mitochondrial transmembrane pore

MW molecular weight

MZ marginal zinc

N nitrogen; normal; north; number; population

n number of observations

Na sodium

Na+ sodium ion

NAAQS National Ambient Air Quality Standards

NAC N-acetyl cysteine; nucleus accumbens

Na2CaEDTA calcium disodium ethylenediaminetetraacetic acid

NaCl sodium chloride

NAD nicotinamide adenine dinucleotide

NADH nicotinamide adenine dinucleotide dehydrogenase
May 2011 xxiii DRAFT – DO NOT CITE OR QUOTE

NADP nicotinamide adenine dinucleotide phosphate

NADPH, NAD(P)H reduced nicotinamide adenine dinucleotide phosphate

NAEC no-adverse-effect concentration

NAG N-acetyl-β-D-glucosaminidase; N-acetylglucosamine 

NaHCO3 sodium bicarbonate; sodium hydrogen carbonate

NANC non-adrenergic non-cholinergic

NAS Normative Aging Study

NASCAR National Association for Stock Car Automobile Racing

NATTS National Air Toxics Trends Station

NAWQA National Water Quality Assessment

NCAM neural cell adhesion molecule 

NCEA National Center for Environmental Assessment

NCore National Core multi-pollutant monitoring network

N.D. not detected

NDMAR N-nitrosodimethylamine receptor

NE norepinephrine

NECAT New England Children’s Amalgam Trial

NEI National Emissions Inventory

NFI non-fixed interval

NF-κB nuclear factor kappa B

NGAL neutrophil gelatinase-associated lipocalin

NGF nerve growth factor 

NH non-hispanic

NHANES National Health and Nutrition Examination Survey

NH4Cl ammonium chloride

NHEJ non-homologous end joining

NHEXAS National Human Exposure Assessment Survey

NH4OAc ammonium acetate

7-NI 7-nitroinidazole 

Ni nickel

NICA non-ideal competitive absorption

NIOSH National Institute for Occupational Safety and Health

NIST National Institute of Standards and Technology

NK natural killer

NKF-K/DOQI National Kidney Foundation - Kidney Disease Outcomes Quality 

Initiative

NMDA N-methyl-D-aspartate

NMR nuclear magnetic resonance

nNOS neuronal nitric oxide synthase (NOS)

NO nitric oxide; nitrogen monoxide

NO2 nitrogen dioxide

No. number

NOAA National Oceanic and Atmospheric Administration

NOAEL no observed adverse effect level

NOEC no-observed-effect concentration

NOEL no-observed-effect level

NOS nitric oxide synthase; nitric oxide systems

NOX nitrogen oxides, oxides of nitrogen (NO + NO2)

NP nanoparticle

NPSH nonprotein sulfhydryl 

NQO1 NAD(P)H-quinone oxidoreductase (genotype)

NRC National Research Council
May 2011 xxiv DRAFT – DO NOT CITE OR QUOTE

NRCS Natural Resouces Conservation Service

Nrf2 nuclear factor erythroid 2-related factor 2

NS not specified

NTPDase nucleoside triphosphate diphosphohydrolase

NW northwest

NYC New York City

NZ New Zealand

O2 molecular oxygen

O2

- superoxide

O3 ozone

9-O-Ac-GD3 9-O-acetylated-GD3

OAQPS U.S. EPA Office of Air Quality Planning and Standards, in OAR

OAR U.S. EPA Office of Air and Radiation

OBS observations

OC organic carbon

OEPA Ohio Environmental Protection Agency

OH- hydroxide ion

1,25-(OH)2D3 1,25-dihydroxy vitamin D 

O-horizon horizon forest floor, organic soil horizon (above surface soil)

OLC osteoblast-like cells

OM organic matter

ONL outer neuroblastic layers of the retina 

ONOO- peroxynitrate ion

OR odds ratio

ORD U.S. EPA Office of Research and Development

OS offspring stress

OSHA Occupational Safety and Health Administration

OVA ovalbumin

8-oxo-dG 8-hydroxy-2’-deoxyguanosine

P percentile; phosphorus

P0 parent generation

P450 cytochrome P450

p probability value; number of paried hourly observations; statistical 

significance

PAD peripheral arterial disease

PAH(s) polycyclic aromatic hydrocarbon(s)

Pb lead 203Pb lead-203 radionuclide 204Pb stable isotope of lead-204 206Pb stable isotope of lead-206 207Pb stable isotope of lead-207 208Pb stable isotope of lead-208 210Pb stable isotope of lead-210

Pb++ divalent Pb ion

Pb0 elemental lead

Pb(II) lead (II)

Pb2+ lead ion

Pb(Ac)2 lead acetate

PbB blood lead concentration

PbBrCl lead bromochloride

Pb(C2H3O2)2 lead (II) acetate

PbCl+ lead chloride
May 2011 xxv DRAFT – DO NOT CITE OR QUOTE

PbCl2 lead chloride

PbCl3 lead (III) chloride; lead trichloride

PbCl4 lead (IV) chloride; lead tetrachloride

PbCO3 cerrusite; lead carbonate 

Pb(CO3)2 lead (IV) carbonate

Pb(CO3)2(OH)2 hydrocerussite

PbCrO4 lead (II) chromate

PbD floor dust lead

PbFe6(SO4)4(OH)12 plumbjarosite

PBG porphobilinogen

Pb(NO3)2 lead(II) nitrate

Pb-NS lead-no stress

PbO lead oxide; litharge; massicot

PbO2 lead dioxide

Pb(IV)O2 lead dioxide

Pb3O4 minimum or "red Pb"

Pb(OH)2 lead hydroxide

Pb5(PO4)3Cl pyromorphite

Pb5(PO4)3OH hydroxypyromorphite

PbS galena; lead sulfide; soil lead concentration

PbSe lead selenide

PbSO4 anglesite; lead sulfate

Pb4SO4(CO3)2(OH)3 macphersonite

PbxS lead by stress

Pb5(VO4)3Cl vanadinite

PC12 pheochromocytoma 12 (adrenal / neuronal cell line)

PCA principal component analysis

PCE polychromatic erythrocyte

PCR polymerase chain reaction

Pct percent

PCV packed cell volume

PD Parkinson's Disease

PDI Psychomotor Development Index 

PEC probable effect concentration

PEL permissible exposure limit

PER partial exfiltration reactor

PG prostaglandin 

PGE2, PGE2 prostaglandin E2

PGF2 prostaglandin F2

pH relative acidity; Log of the reciprocal of the hydrogen ion 

concentration

PHA polyhydroxyalkanoates

PHE phenylalanine

PIH pregnancy induced hypertension

PIQ performance intelligence quotient (IQ)

PIR poverty-income ratio

PIXE particle induced X-Ray emission; proton-induced x-ray emission

PKC protein kinase C

PLP proteolipid protein

PM particulate matter
May 2011 xxvi DRAFT – DO NOT CITE OR QUOTE

PMX Particulate matter of a specific size range not defined for regulatory 

use. Usually X refers to the 50% cut point, the aerodynamic diameter 

at which the sampler collects 50% of the particles and rejects 50% of 

the particles. The collection efficiency, given by a penetration curve, 

increases for particles with smaller diameters and decreases for 

particles with larger diameters. The definition of PMX is sometimes 

abbreviated as “particles with a nominal aerodynamic diameter less 

than or equal to X μm” although X is usually a 50% cut point.

PM10 In general terms, particulate matter with an aerodynamic diameter less 

than or equal to a nominal 10 μm; a measurement of thoracic particles 

(i.e., that subset of inhalable particles thought small enough to 

penetrate beyond the larynx into the thoracic region of the respiratory 

tract) in regulatory terms, particles with an upper 50% cut-point of 

10± 0.5 μm aerodynamic diameter (the 50% cut point diameter is the 

diameter at which the sampler collects 50% of the particles and rejects 

50% of the particles) and a penetration curve as measured by a 

reference method based on Appendix J of 40 CFR Part 50 and 

designated in accordance with 40 CFR Part 53 or by an equivalent 

method designated in accordance with 40 CFR Part 53.

PM2.5 In general terms, particulate matter with an aerodynamic diameter less 

than or equal to a nominal 2.5 μm; a measurement of fine particles in 

regulatory terms, particles with an upper 50% cut-point of 2.5 μm 

aerodynamic diameter (the 50% cut point diameter is the diameter at 

which the sampler collects 50% of the particles and rejects 50% of the 

particles) and a penetration curve as measured by a reference method 

based on Appendix L of 40 CFR Part 50 and designated in accordance 

with 40 CFR Part 53, by an equivalent method designated in 

accordance with 40 CFR Part 53, or by an approved regional method 

designated in accordance with Appendix C of 40 CFR Part 58.

PM10-2.5 In general terms, particulate matter with an aerodynamic diameter less 

than or equal to a nominal 10 μm and greater than a nominal 2.5 μm; 

a measurement of thoracic coarse particulate matter or the coarse 

fraction of PM10 in regulatory terms, particles with an upper 50% 

cut-point of 10 μm aerodynamic diameter and a lower 50% cut-point 

of 2.5 μm aerodynamic diameter (the 50% cut point diameter is the 

diameter at which the sampler collects 50% of the particles and rejects 

50% of the particles) as measured by a reference method based on 

Appendix O of 40 CFR Part 50 and designated in accordance with 40 

CFR Part 53 or by an equivalent method designated in accordance 

with 40 CFR Part 53.

PM10C The PM10-2.5 concentration of PM10-2.5 measured by the 40 CFR Part 

50 Appendix O reference method which consists of currently 

operated, collocated low-volume (16.7 Lpm) PM10 and PM2.5

reference method samplers.

p38MAPK p38 mitogen-activated protein kinase(s)

PMN polymorphonuclear leukocyte

P5N pyrimidine 5'-nucleotidase 

PND post natal day

POC particulate organic carbon

PP polypropylene; pulse pressure 

ppb parts per billion

ppm parts per million

PRP post-reinforcement pause

PS dam stress; prenatal stress; phosphatidylserine

PSA prostate specific antigen 

PSA-NCAM polysialylated-neural cell adhesion molecule 

PT proximal tubule

PTFE polytetrafluoroethylene

PTHrP parathyroid hormone-related protein

PUFA polyunsaturated fatty acid

PVC polyvinyl chloride
May 2011 xxvii DRAFT – DO NOT CITE OR QUOTE

PVD peripheral vascular disease

Q quantile; quartile; quintile

QRS QRS complex in ECG

QT QT interval in ECG

QTc corrected QT Interval

ρ rho; bulk density; correlation

ρS Pearson's r correlation coefficient

R net drainage loss out of soil depth of concern; Spearman correlation 

coefficient; upward resuspension flux; correlation

r Pearson correlation coefficient

R2 multiple regression correlation coefficient 

r

2 correlation coefficient

RAAS renin-angiotensin-aldosterone system

RAC2 gene encoding for Rac2

RBA relative bioavailability

RBC red blood cell

RBP retinol binding protein

RD radial diffusivity

Ref reference (group)

RI-RI concurrent random interval

RL repeated learning 220Rn radon isotope 222Rn stable isotope of radon-222

RNA ribonucleic acid

ROI reactive oxygen intermediate/superoxide anion; regions of interest

ROS reactive oxygen species

RR relative risk; risk ratio

RSL roughness sublayer (transition layer, wake layer, interfacial layer)

rtPCR reverse transcription polymerase chain reaction

σ sigma, standard deviation

S south; sulfur; synthesis phase

SAB U.S. EPA Science Advisory Board

SATs Standard Assessment Tests 

SBP systolic blood pressure

SCE sister chromatid exchange

Scna α-synuclein

SD standard deviation

SDN sexually dimorphic nucleus

SE standard error

Se selenium

sec second(s)

SEM scanning electron microscopy; simultaneously extracted metal; 

standard error of the mean

SES socioeconomic status

Sess. session

SGA small for gestational age

sGC soluble guanylate cyclase

sGC-β1 soluble guanylate cyclase-beta 1

SGOT serum glutamic oxaloacetic transaminase

SGPT serum glutamic pyruvic transaminase

SHBG sex hormone binding globulin

SHM Stockholm humic model
May 2011 xxviii DRAFT – DO NOT CITE OR QUOTE

siRNA small interfering RNA

SJW silver jewelry workers

SLAMS State and Local Air Monitoring Stations

SMC smooth muscle cells

SNAP-25 synaptosomal-associated protein 25

SNARE soluble NSF attachment receptor

SNP single-nucleotide polymorphism; sodium nitroprusside

SNS sympathetic nervous system

SO stratum oriens 

SO2 sulfur dioxide

So south

SOC superior olivary complex 

SOD superoxide dismutase

SOD1 superoxide dismutase-1

SOF study of osteoporotic fractures

SOM self-organizing map

SP spray painters

SP1, Sp1 specificity protein 1

SPM suspended particulate matter

SPT skin prick test

SREBP-2 sterol regulatory element binding protein-2

S. Rep. Senate Report

SRIXE synchrotron radation induced X-ray emission

StAR steroidogenic acute regulatory protein

STAT signal transducer and activator of transcription

STAT3 signal transducer and activator of transcription 3

STAT5 signal transducer and activator of transcription 5

STD. Standard

ST Interval measured from the J point to the end of the T wave in an ECG

Syb synaptobrevin

Syn synaptophysin

Syt synaptotagmin 

SZn supplemental zinc 

T, t time

T3, T3 triiodothyronine

T4, T4 thyroxine

t1/2 half-life (-lives); time required to reduce the initial concentration by 

50%

TBARS thioBarbituric acid reactive substances; thiobarbituric acid-reactive 

species 

T cell, T-cell T lymphocyte

TE trace elements

TEC threshold effect concentrations

TF ratio of the metal concentration in plant to that in soil; transferrin

TFIIIA transcription factor IIIA

Tg transgenic

TGF transforming growth factor

TGF-β β transforming growth factor

TGFβ1, TGF-β1 β1 transforming growth factor

TH tyrosine hydroxylase

TH1, Th1 T-derived lymphocyte helper 1

TH2, Th2 T-derived lymphocyte helper 2
May 2011 xxix DRAFT – DO NOT CITE OR QUOTE

Th T-helper lymphocyte

TIMP-1 tissue inhibitor of metalloproteinases-1

TIMS thermal ionization mass spectrometry

TLC Treatment of Lead-exposed Children (study)

T/LH testosterone/luteinizing hormone - measure of Leydig cell function

TNF tumor necrosis factor (e.g., TNF-α)

TNP-Ficoll trinitrophenyl-ficoll 

TNP-OVA trinitrophenyl-ovalabumin 

TPR total peripheral vascular resistance

TS transferrin saturation 

TSH thyroid stimulating hormone; total sulfhydryl

TSP total suspended particles

TSS total suspended solids

TXB2 thromboxane

UA urbanized area

UBL urban boundary layer

UCL urban canopy layer

UDPGT uridine diphosphate (UDP)-glucuronosyltransferase(s)

U.K. United Kingdom

U.S. United States of America

USC U.S. Code

U.S. EPA United States Environmental Protection Agency

USF uptake slope factor

USGS United States Geological Survey

USL urban surface layer

UUDS urban dynamic driving schedule

UV ultraviolet radiation

V vanadium

V79 Chinese hamster lung cell line

VA Veterans Administration

VAChAT vesicular acetylcholine transporter

VAMP-2 vesicle-associated membrane protein-2

VA-NAS Veterans Administration Normative Aging Study

VDAC voltage-dependent anion channel

VDR vitamin D receptor

VGAT vesicular gamma aminobutyric acid (GABA) transporter

VGLUT1 vesicular glutamate transporter 1

VIQ verbal intelligence quotient (IQ)

VLPb very low lead

VMAT2 vesicular monoamine transporter-2

VO4

3- vanadate ion

VOC(s) volatile organic compound(s)

vs., v. versus

VSMC vascular smooth muscle cells

WACAP Western Airborne Contaminants Assessment Project

WBC white blood cell 

WCST Wisconsin Card Sorting Test 

WHAM Windermere humic aqueous model

WHO World Health Organization

WIAT Wechsler Individual Achievement Test

WISC Weschler Intelligence Scale for Children

WISC-R Weschler Intelligence Scale for Children-Revised
May 2011 xxx DRAFT – DO NOT CITE OR QUOTE

wk week(s)

WML white matter lesions 

WPPSI-III Wechsler Preschool and Primary Scales of Intelligence-III

WPPSI-R Weschler Preschool and Primary Scale of Intelligence-Revised

WRAT Wide Range Achievement Test

W/S winter/summer

WT wild type

wt. weight

XAFS X-ray absorption fine structure

XANES X-ray absorption near edge structure

XDH xanthine dehydrogenase

Xij observed hourly concentrations for time period i at site j

Xik observed hourly concentrations for time period i at site k

XPS X-ray photoelectron spectroscopy

XRF X-ray fluorescence

yr year(s)

Zn zinc

Zn2+ zinc ion

ZPP zirconium-potassium perchlorate; zinc protoporphyrin 

Z-score standard score