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Toxicity Testing for Assessment of Environmental Agents: Interim Report
Toxicity Testing for Assessment of Environmental Agents
Interim Report
Committee on Toxicity Testing and Assessment of Environmental Agents
Board on Environmental Studies and Toxicology
Institute for Laboratory Animal Research
Division on Earth and Life Studies
NATIONAL RESEARCH COUNCIL OF THE NATIONAL ACADEMIES
THE NATIONAL ACADEMIES PRESS
Washington, D.C.
www.nap.edu
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Toxicity Testing for Assessment of Environmental Agents: Interim Report
THE NATIONAL ACADEMIES PRESS
500 Fifth Street, NW Washington, DC 20001
NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.
This project was supported by Contract No. 68-C-03-081 between the National Academy of Sciences and the U.S. Environmental Protection Agency. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of the organizations or agencies that provided support for this project.
International Standard Book Number 0-309-10092-5 (Book)
International Standard Book Number 0-309-65652-4 (PDF)
Library of Congress Control Number 2006923288
Additional copies of this report are available from
The National Academies Press
500 Fifth Street, NW Box 285 Washington, DC 20055 800-624-6242 202-334-3313 (in the Washington metropolitan area) http://www.nap.edu
Copyright 2006 by the National Academy of Sciences. All rights reserved.
Printed in the United States of America
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Toxicity Testing for Assessment of Environmental Agents: Interim Report
THE NATIONAL ACADEMIES
Advisers to the Nation on Science, Engineering, and Medicine
The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Ralph J. Cicerone is president of the National Academy of Sciences.
The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Wm. A. Wulf is president of the National Academy of Engineering.
The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Harvey V. Fineberg is president of the Institute of Medicine.
The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Ralph J. Cicerone and Dr. Wm. A. Wulf are chair and vice chair, respectively, of the National Research Council.
www.national-academies.org
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COMMITTEE ON TOXICITY TESTING AND ASSESSMENT OF ENVIRONMENTALAGENTS
Members
DANIEL KREWSKI (Chair),
University of Ottawa, Ottawa, ON
DANIEL ACOSTA, JR.,
University of Cincinnati, Cincinnati, OH
MELVIN ANDERSEN,
CIIT Centers for Health Research, Research Triangle Park, NC
HENRY ANDERSON,
Wisconsin Division of Public Health, Madison
JOHN BAILAR III,
University of Chicago, Chicago, IL
KIM BOEKELHEIDE,
Brown University, Providence, RI
ROBERT BRENT,
Thomas Jefferson University, Wilmington, DE
GAIL CHARNLEY,
HealthRisk Strategies, Washington, DC
VIVIAN CHEUNG,
University of Pennsylvania, Philadelphia
SIDNEY GREEN,
Howard University, Washington, DC
KARL KELSEY,
Harvard University, Boston, MA
NANCY KERKVLIET,
Oregon State University, Corvallis
ABBY LI,
Exponent, Inc., San Francisco, CA
GEORGE LUCIER, Consultant,
Pittsboro, NC
LAWRENCE MCCRAY,
Massachusetts Institute of Technology, Cambridge
OTTO MEYER,
Danish Institute for Food and Veterinary Research, Søborg, Denmark
D. REID PATTERSON,
Reid Patterson Consulting, Inc., Grayslake, IL
WILLIAM PENNIE,
Pfizer, Inc., Groton, CT
ROBERT SCALA,
Exxon Biomedical Sciences (Ret.), Tucson, AZ
GINA SOLOMON,
Natural Resources Defense Council, San Francisco, CA
MARTIN STEPHENS,
The Humane Society of the United States, Washington, DC
JAMES YAGER, JR.,
Johns Hopkins University, Baltimore, MD
LAUREN ZEISE,
California Environmental Protection Agency, Oakland
Staff
ELLEN MANTUS, Study Director
ROBERTA WEDGE, Study Director (through January 2005)
JOANNE ZURLO, Board Director
JENNIFER OBERNIER, Program Officer
NORMAN GROSSBLATT, Senior Editor
JENNIFER D. ROBERTS, Postdoctoral Research Associate
MIRSADA KARALIC-LONCAREVIC, Research Associate
JORDAN CRAGO, Senior Project Assistant
LUCY FUSCO, Senior Project Assistant
ALEXANDRA STUPPLE, Senior Editorial Assistant
Sponsor
U.S. ENVIRONMENTAL PROTECTION AGENCY
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BOARD ON ENVIRONMENTAL STUDIES AND TOXICOLOGY
Members
JONATHAN M. SAMET (Chair),
Johns Hopkins University, Baltimore, MD
RAMÓN ALVAREZ,
Environmental Defense, Austin, TX
JOHN M. BALBUS,
Environmental Defense, Washington, DC
THOMAS BURKE,
Johns Hopkins University, Baltimore, MD
DALLAS BURTRAW,
Resources for the Future, Washington, DC
JAMES S. BUS,
Dow Chemical Company, Midland, MI
COSTEL D. DENSON,
University of Delaware, Newark
E. DONALD ELLIOTT,
Willkie Farr & Gallagher LLP, Washington, DC
J. PAUL GILMAN,
Oak Ridge National Laboratory, Oak Ridge, TN
SHERRI W. GOODMAN,
Center for Naval Analyses, Alexandria, VA
JUDITH A. GRAHAM,
American Chemistry Council, Arlington, VA
DANIEL S. GREENBAUM,
Health Effects Institute, Cambridge, MA
WILLIAM P. HORN,
Birch, Horton, Bittner and Cherot, Washington, DC
ROBERT HUGGETT,
Michigan State University (emeritus), East Lansing
JAMES H. JOHNSON, JR.,
Howard University, Washington, DC
JUDITH L. MEYER,
University of Georgia, Athens
PATRICK Y. O’BRIEN,
ChevronTexaco Energy Technology Company, Richmond, CA
DOROTHY E. PATTON,
International Life Sciences Institute, Washington, DC
STEWARD T.A. PICKETT,
Institute of Ecosystem Studies, Millbrook, NY
DANNY D. REIBLE,
University of Texas, Austin
JOSEPH V. RODRICKS,
ENVIRON International Corporation, Arlington, VA
ARMISTEAD G. RUSSELL,
Georgia Institute of Technology, Atlanta
LISA SPEER,
Natural Resources Defense Council, New York, NY
KIMBERLY M. THOMPSON,
Massachusetts Institute of Technology, Cambridge
MONICA G. TURNER,
University of Wisconsin, Madison
MARK J. UTELL,
University of Rochester Medical Center, Rochester, NY
CHRIS G. WHIPPLE,
ENVIRON International Corporation, Emeryville, CA
LAUREN ZEISE,
California Environmental Protection Agency, Oakland
Senior Staff
JAMES J. REISA, Director
DAVID J. POLICANSKY, Scholar
RAYMOND A. WASSEL, Senior Program Officer for Environmental Sciences and Engineering
KULBIR BAKSHI, Senior Program Officer for Toxicology
EILEEN N. ABT, Senior Program Officer for Risk Analysis
K. JOHN HOLMES, Senior Program Officer
SUSAN N.J. MARTEL, Senior Program Officer
SUZANNE VAN DRUNICK, Senior Program Officer
ELLEN K. MANTUS, Senior Program Officer
RUTH E. CROSSGROVE, Senior Editor
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INSTITUTE FOR LABORATORY ANIMAL RESEARCH COUNCIL
Members
PETER A. WARD (Chair),
University of Michigan, Ann Arbor
STEPHEN W. BARTHOLD,
University of California, Davis
WILLIAM C. CAMPBELL,
Drew University, Madison, NJ
JEFFREY EVERITT,
GlaxoSmithKline Research & Development, Research Triangle Park, NC
MICHAEL F. FESTING,
Leicestershire, United Kingdom
ESTELLE B. GAUDA,
Johns Hopkins University, Baltimore, MD
JANET C. GONDER,
Pinehurst, NC
COENRAAD F.M. HENDRIKSEN,
National Institute of Public Health and the Environment, Bilthoven, Netherlands
JAY R. KAPLAN,
Wake Forest University School of Medicine, Winston-Salem, NC
HILTON J. KLEIN,
Merck Research Laboratories, West Point, PA
WILLIAM MORTON,
University of Washington, Seattle
RANDALL J. NELSON,
University of Tennessee, Memphis
ABIGAIL SMITH,
University of Pennsylvania, Philadelphia
MICHAEL K. STOSKOPF,
North Carolina State University, Raleigh
PETER THERAN,
Massachusetts Society for the Prevention of Cruelty to Animals, Boston
Staff
JOANNE ZURLO, Director
KATHLEEN BEIL, Administrative Assistant
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Toxicity Testing for Assessment of Environmental Agents: Interim Report
OTHER REPORTS OF THE BOARD ON ENVIRONMENTAL STUDIES AND TOXICOLOGY
Superfund and Mining Megasites—Lessons from the Coeur d’Alene River Basin (2005)
Health Implications of Perchlorate Ingestion (2005)
Air Quality Management in the United States (2004)
Endangered and Threatened Species of the Platte River (2004)
Atlantic Salmon in Maine (2004)
Endangered and Threatened Fishes in the Klamath River Basin (2004)
Cumulative Environmental Effects of Alaska North Slope Oil and Gas Development (2003)
Estimating the Public Health Benefits of Proposed Air Pollution Regulations (2002)
Biosolids Applied to Land: Advancing Standards and Practices (2002)
The Airliner Cabin Environment and Health of Passengers and Crew (2002)
Arsenic in Drinking Water: 2001 Update (2001)
Evaluating Vehicle Emissions Inspection and Maintenance Programs (2001)
Compensating for Wetland Losses Under the Clean Water Act (2001)
A Risk-Management Strategy for PCB-Contaminated Sediments (2001)
Acute Exposure Guideline Levels for Selected Airborne Chemicals (4 volumes, 2000-2004)
Toxicological Effects of Methylmercury (2000)
Strengthening Science at the U.S. Environmental Protection Agency (2000)
Scientific Frontiers in Developmental Toxicology and Risk Assessment (2000)
Ecological Indicators for the Nation (2000)
Waste Incineration and Public Health (1999)
Hormonally Active Agents in the Environment (1999)
Research Priorities for Airborne Particulate Matter (4 volumes, 1998-2004)
The National Research Council’s Committee on Toxicology: The First 50 Years (1997)
Carcinogens and Anticarcinogens in the Human Diet (1996)
Upstream: Salmon and Society in the Pacific Northwest (1996)
Science and the Endangered Species Act (1995)
Wetlands: Characteristics and Boundaries (1995)
Biologic Markers (5 volumes, 1989-1995)
Review of EPA’s Environmental Monitoring and Assessment Program (3 volumes, 1994-1995)
Science and Judgment in Risk Assessment (1994)
Pesticides in the Diets of Infants and Children (1993)
Dolphins and the Tuna Industry (1992)
Science and the National Parks (1992)
Human Exposure Assessment for Airborne Pollutants (1991)
Rethinking the Ozone Problem in Urban and Regional Air Pollution (1991)
Decline of the Sea Turtles (1990)
Copies of these reports may be ordered from the National Academies Press
(800) 624-6242 or (202) 334-3313
www.nap.edu
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INSTITUTE FOR LABORATORY ANIMAL RESEARCH PUBLICATIONS
Science, Medicine, and Animals: A Circle of Discovery (2004)
The Development of Science-Based Guidelines for Laboratory Animal Care: Proceedings of the November 2003 International Workshop (2004)
National Need and Priorities for Veterinarians in Biomedical Research (2004)
Occupational Health and Safety in the Care and Use of Nonhuman Primates (2003)
International Perspectives—The Future of Nonhuman Primate Resources: Proceedings of the Workshop Held April 17-19, 2002 (2003)
Guidelines for the Care and Use of Mammals in Neuroscience and Behavioral Research (2003)
Principles and Guidelines for the Use of Animals in Precollege Education (2001)
Strategies That Influence Cost Containment in Animal Research (2000)
Definition of Pain and Distress and Reporting Requirements for Laboratory Animals: Proceedings of the Workshop Held June 22, 2000 (2000)
Monoclonal Antibody Production (1999)
Microbial and Phenotypic Definition of Rats and Mice: Proceedings of the 1999 US/Japan Conference (1999)
The Psychological Well-Being of Nonhuman Primates (1998)
Microbial Status and Genetic Evaluation of Mice and Rats: Proceedings of the 1998 US/Japan Conference (1998)
Biomedical Models and Resources: Current Needs and Future Opportunities (1998)
Approaches to Cost Recovery for Animal Research: Implications for Science, Animals, Research Competitiveness, and Regulatory Compliance (1998)
Occupational Health and Safety in the Care and Use of Research Animals (1997)
Chimpanzees in Research: Strategies for Their Ethical Care, Management, and Use (1997)
Guide for the Care and Use of Laboratory Animals, 7th ed. (1996)
Nutrient Requirements of Laboratory Animals, 4th ed. (1995)
Laboratory Animal Management: Dogs (1994)
Recognition and Alleviation of Pain and Distress in Laboratory Animals (1992)
Infectious Diseases of Mice and Rats (1991)
Companion Guide to Infectious Diseases of Mice and Rats (1991)
Laboratory Animal Management: Rodents (1990)
Immunodeficient Rodents: A Guide to Their Immunobiology, Husbandry, and Use (1989)
Use of Laboratory Animals in Biomedical and Behavioral Research (1988)
Copies of these reports may be ordered from the National Academies Press
(800) 624-6242 or (202) 334-3313
www.nap.edu
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Toxicity Testing for Assessment of Environmental Agents: Interim Report
This report is dedicated to the memory
of our fellow committee member,
Dr. Herbert Rosenkranz
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Abbreviations
ACD
acute contact dermatitis
ACS
American Cancer Society
ADJ
adjustment factor
ADME
absorption, distribution, metabolism, and excretion
AEGL
acute exposure guideline level
AhR
aryl hydrocarbon receptor
ARNT
AhR nuclear translocator
BBDR
biologically based dose response
BMC
benchmark concentration
BMD
benchmark dose
BT
Buehler test
CDC
Centers for Disease Control and Prevention
CFR
Code of Federal Regulations
CNS
central nervous system
CSA
chemical safety assessment
CYPs
cytochrome P450s
DAF
dosimetric adjustment factor
EC
European Commission
ECVAM
European Centre for the Validation of Alternative Methods
EDSP
Endocrine Disruptor Screening Program
EDSTAC
Endocrine Disruptor Screening and Testing Advisory Committee
EGP
Environmental Genome Project
ELISA
enzyme-linked immunosorbent assay
EPA
Environmental Protection Agency
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EPHT
environmental public-health tracking
EU
European Union
FDA
Food and Drug Administration
FEV1
forced expiratory volume in 1 second
FFDCA
Federal Food, Drug, and Cosmetics Act
FIFRA
Federal Insecticide, Fungicide, and Rodenticide Act
FQPA
Food Quality Protection Act
GD
gestational day
GFP
green fluorescent protein
GMPT
guinea pig maximization test
HESI
Health and Environmental Sciences Institute
HPV
high-production volume
HTS
high-throughput screening
HUPO
Human Proteome Organization
IARC
International Agency for Research on Cancer
IC50
inhibition concentrations 50%
ICCVAM
Interagency Coordinating Committee on the Validation of Alternative Methods
ICH
International Conference on Harmonization
IgM
immunoglobulin M
ILSI
International Life Sciences Institute
IOM
Institute of Medicine
IPCS
International Programme on Chemical Safety
LC50
lethal concentration 50%
LD50
lethal dose 50%
LLNA
local lymph node assay
LOAEL
lowest-observed-adverse-effect level
MPCA
microbial pest-control agent
MTS
medium-throughput screening
NAAQS
national ambient air quality standards
NICEATM
NTP Interagency Center for the Evaluation of Alternative Toxicological Methods
NIEHS
National Institute of Environmental Health Sciences
NOAEL
no-observed-adverse-effect level
NRC
National Research Council
NTP
National Toxicology Program
OECD
Organisation for Economic Co-operation and Development
OSHA
Occupational Safety and Health Administration
PAH
polycyclic aromatic hydrocarbon
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PBPK
physiologically based pharmacokinetic
PBT
persistence, bioaccumulation, and toxicity
PK
pharmacokinetic
PMN
premanufacturing notice
PND
postnatal day
QSAR
quantitative structure-activity relationship
REACH
Registration, Evaluation and Authorisation of Chemicals
RfC
Reference concentration
RfD
Reference dose
SAR
structure-activity relationship
SIDS
screening information dataset
SNP
single-nucleotide polymorphism
SRBCs
sheep red blood cells
TCDD
2,3,7,8-tetrachlorodibenzo-p-dioxin
TG
testing guideline
TGD
technical guidance document
TSC
the SNP Consortium
TSCA
Toxic Substances Control Act
UDP
up-down procedure
UF
uncertainty factor
UN
United Nations
vPvB
very persistent and very bioaccumulative
WHO
World Health Organization
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Contents
SUMMARY
1
1
INTRODUCTION
15
Regulatory Requirements,
16
Toxicity Testing,
16
Challenges to Toxicity Testing and Assessment,
20
Committee’s Task and Approach,
21
Organization of the Report,
23
References,
24
2
ANIMAL AND IN VITRO TOXICITY TESTING
26
Toxicity Testing Characterized by Exposure Duration,
29
Toxicity Testing Characterized by Specific End Point,
35
Mechanistic Testing: Metabolism and Pharmacokinetic Studies,
57
References,
59
3
HUMAN DATA
71
Clinical or Controlled-Exposure Studies,
72
Case Reports,
73
Epidemiologic Studies,
74
Use of Human Data for Regulatory Analyses,
76
Challenges to the Advancement of Epidemiology,
79
Contributions of Emerging Fields to Epidemiology,
80
References,
85
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4
STRATEGIES FOR TOXICITY TESTING
92
Types of Toxicity-Testing Strategies,
93
Toxicity-Testing Strategies for Pesticides and Food Additives,
94
Toxicity-Testing Strategies for Screening of Industrial Chemicals,
99
Strategies for Screening Chemicals for Effects on Specific Systems and End Points,
102
Committee Observations on Toxicity-Testing Strategies,
112
References,
115
5
USE OF DATA IN HUMAN HEALTH RISK ASSESSMENT
118
Noncancer Risk-Assessment Guidance,
120
Cancer Risk-Assessment Guidance,
133
Committee Observations Concerning Toxicity Data Available for Risk Assessment,
140
References,
144
6
NEW APPROACHES
149
Approaches for Improving Existing Toxicity-Testing Strategies,
151
Committee Evaluation of Suggested Improvements in Testing Strategies,
185
References,
191
7
ALTERNATIVE APPROACHES AND EMERGING TECHNOLOGIES
194
Alternatives to Current Animal-Testing Approaches,
195
Emerging Technologies,
202
Validation,
216
References,
220
APPENDIXES
A.
Biographic Information on the Committee on Toxicity Testing and Assessment of Environmental Agents
230
B.
Testing Protocols
240
BOXES
4-1
Human Health Data to Be Obtained with Basic SIDS Testing Battery,
100
6-1
Roadmap Activities: High-Throughput Screening (HTS),
184
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FIGURES
4-1
Endocrine-disruptor screening program overview,
105
4-2
Developmental-toxicity testing approach,
110
5-1
IPCS (1999) subdivision of interspecies and intraspecies uncertainty factors into pharmacokinetic and pharmacodynamic components,
128
6-1
The four objectives of toxicity testing,
150
6-2
Guideline study designs used to derive the oral reference dose,
153
6-3
Expanded chronic-carcinogenicity study,
156
6-4
ILSI-HESI draft proposed tiered approach for systemic-toxicity evaluation,
169
6-5
ILSI-HESI draft proposed tiered life-stages testing scheme for pesticides,
171
TABLES
1-1
Some Major U.S. Regulatory Agency Authority, Public-Health Goals, and Risk-Management Approaches,
17
2-1
EPA Acute-Toxicity Categories,
30
2-2
Representative Genetic Toxicology Tests,
49
2-3
Representative Validated In Vitro Methods for Cellular-Toxicity Testing,
53
3-1
Examples of Epidemiologic Study Designs,
74
3-2
Examples of Risks or Standards Derived from Human Data,
76
4-1
Battery of Tests Required by EPA for New Pesticide Chemicals,
95
4-2
Toxicity Tests for Microbial Pest-Control Agents,
96
4-3
Concern Levels for Direct Food Additives,
97
4-4
Testing Required for Direct and Indirect Food Additives,
98
4-5
European Union Testing Strategy,
103
4-6
Endocrine-Disruptor Screening Tests,
106
4-7
OECD Conceptual Framework for Testing Endocrine Disruptors,
108
5-1
EPA’s Weight-of-Evidence Approach for Evaluating Degree of Concern for Prenatal and Postnatal Toxicity on the Basis of Human and Animal Data,
131
5-2
Level of Evidence in Carcinogen Classification Schemes or Narrative Descriptions,
135
6-1
REACH Testing Strategy,
178
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Toxicity Testing for Assessment
of Environmental Agents
Interim Report
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