Review of Texas Commission on Environmental Quality’s Ethylene Oxide Development Support Document

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Committee to Review Texas Commission on Environmental Quality’s Ethylene Oxide Development Support Document

Board on Environmental Studies and Toxicology

Division on Earth and Life Studies

Consensus Study Report

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This activity was supported by a contract between the National Academy of Sciences and the Texas Commission on Environmental Quality (Contract Number AWD-001984). Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.

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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2025. Review of Texas Commission on Environmental Quality’s Ethylene Oxide Development Support Document. Washington, DC: National Academies Press. https://doi.org/10.17226/28592.

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COMMITTEE TO REVIEW TEXAS COMMISSION ON ENVIRONMENTAL QUALITY’S ETHYLENE OXIDE DEVELOPMENT SUPPORT DOCUMENT

DAVID C. DORMAN (Chair), North Carolina State University

DEBORAH H. BENNETT, University of California, Davis

ANNECLAIRE J. DE ROOS, Drexel University

ELLEN A. EISEN, University of California, Berkeley

WENDY HEIGER-BERNAYS, Boston University

CARMEN J. MARSIT, Emory University

KEEVE E. NACHMAN, Johns Hopkins Bloomberg School of Public Health

ANNE E. NIGRA, Columbia University

CRAIG ROWLANDS, UL Solutions

VERONICA M. VIEIRA, University of California, Irvine

JOSEPH WIEMELS, University of Southern California (until December 2024)

National Academies of Sciences, Engineering, and Medicine Staff

KATHRYN Z. GUYTON, Study Director

KELSEY BABIK, Associate Program Officer (until August 2024)

ANTHONY DEPINTO, Program Officer

SABINA VADNAIS, Associate Program Officer (since October 2024)

LESLIE BEAUCHAMP, Senior Program Assistant (until October 2024)

ZOE ALEXANDER, Senior Program Assistant (since October 2024)

BOARD ON ENVIRONMENTAL STUDIES AND TOXICOLOGY

FRANK W. DAVIS (Chair), University of California, Santa Barbara

DANA BOYD BARR, Emory University

WEIHSUEH A. CHIU, Texas A&M University

FRANCESCA DOMINICI, Harvard University

CORIE A. ELLISON, The Procter & Gamble Company

MAHMUD FAROOQUE, Arizona State University

MARIE C. FORTIN, Merck

MARIE L. MIRANDA, University of Illinois Chicago

MELISSA J. PERRY, George Mason University

SACOBY M. WILSON, University of Maryland

TRACEY J. WOODRUFF, University of California, San Francisco

National Academies of Sciences, Engineering, and Medicine Staff

CLIFFORD S. DUKE, Board Director (until May 2025)

NATALIE ARMSTRONG, Program Officer

LESLIE BEAUCHAMP, Senior Program Assistant (until October 2024)

ANTHONY DEPINTO, Program Officer

KATHRYN Z. GUYTON, Senior Program Officer

LAURA LLANOS, Finance Business Partner

THOMASINA LYLES, Senior Program Assistant

Reviewers

This Consensus Study Report was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine in making each published report as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process.

We thank the following individuals for their review of this report:

UDAYAN APTE, University of Kansas

JOHN BAILER, Miami University (retired)

PENELOPE FENNER-CRISP, Independent Consultant

SUE JINKS-ROBERTSON (NAS), Duke University

RASHMI JOGLEKAR, University of California, San Francisco

JULEEN LAM, California State University East Bay

DANA LOOMIS, Plumas County Public Health Agency (retired)

ANDREW OLSHAN, University of North Carolina at Chapel Hill

LORENZ RHOMBERG, Gradient Corporation

KAREN ROBINSON, Johns Hopkins University

JON SAMET (NAM), University of Colorado (retired)

Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations of this report, nor did they see the final draft before its release. The review of this report was overseen by DAVID RICHARDSON, University of California, Irvine, and LYNN GOLDMAN (NAM), George Washington University. They were responsible for making certain that an independent examination of this report was carried out in accordance with the standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the authoring committee and the National Academies.

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Acknowledgments

Many people were essential in helping the committee accomplish its charge. The committee gratefully acknowledges the participants at its information-gathering sessions who provided insights and viewpoints pertinent to the committee’s task. We thank Maureen Gwinn, Kristine Thayer, and Paul White from the U.S. Environmental Protection Agency and Kyle Steenland from Emory University for their contributions during the open session at the committee’s fourth meeting.

In addition, we are grateful to the Texas Commission on Environmental Quality (TCEQ) for sponsoring the study and to the TCEQ staff—Sabine Lange and Joseph (Kip) Haney—for their presentations to the committee.

The committee is grateful to the staff of the National Academies of Sciences, Engineering, and Medicine who contributed to producing this report, especially the outstanding and tireless study staff: Kathryn Guyton, Kelsey Babik, Anthony DePinto, Sabina Vadnais, Leslie Beauchamp, and Zoe Alexander. Thank you also to Elizabeth Boyle of the Health and Medicine Division for her contributions and to the staff of the Division on Earth and Life Studies who provided additional support, including Elizabeth Eide, Lauren Everett, Laura Llanos, Nancy Huddleston, Radiah Rose, and Maggie Walser.

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Contents

ACRONYMS AND ABBREVIATIONS

SUMMARY

1 INTRODUCTION

Ethylene Oxide

Prior Cancer Assessments

Development of Toxicity Values

The Committee’s Task

The Committee’s Approach to the Task

Organization of the Report

2 HAZARD IDENTIFICATION

Previous Cancer Assessments

Systematic Review Process and Considerations

Epidemiological Evidence for Breast Cancer

Experimental Animal Data to Inform Hazard Assessment

MOA Considerations

Findings and Recommendations

3 DOSE-RESPONSE

Consideration of Mortality and Incidence Data

TCEQ’s Dose-Response Assessment for Lymphoid Cancers

NIOSH

UCC

Age-Dependent Adjustment Factors

Influence of MOA on Model Selection

Dose-Response Model Selection

TCEQ’s Systematic Review for Dose-Response

Other Considerations: Endogenous Ethylene Oxide

Findings and Recommendations

REFERENCES

APPENDIX A: COMMITTEE BIOGRAPHIES

APPENDIX B: PUBLIC MEETING AGENDA

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Acronyms and Abbreviations