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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2025. Exploring military exposures and mental, behavioral, and neurologic health outcomes among post-9/11 veterans. Washington, DC: National Academies Press. https://doi.org/10.17226/29219.

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COMMITTEE ON THE MENTAL HEALTH EFFECTS OF TOXIC EXPOSURES AMONG VETERANS

DEBORAH CORY-SLECHTA (Cochair), University of Rochester

JEANNETTE SOUTH-PAUL (Cochair), Meharry Medical College

CARL CASTRO, University of Southern California; USC-RAND Epstein Family Foundation

R. YATES COLEY, Kaiser Permanente Washington Health Research Institute; University of Washington

AISHA S. DICKERSON, Johns Hopkins University

LISA DIXON, Columbia University; New York-Presbyterian; New York State Psychiatric Institute

JAIMIE L. GRADUS, Boston University

PATRICIA JANULEWICZ LLOYD, University of Massachusetts Boston

MARIANTHI-ANNA KIOUMOURTZOGLOU, Columbia University

BHRAMAR MUKHERJEE, Yale University

DAVIN QUINN, University of New Mexico

RAJEEV RAMCHAND, RAND

JACK TSAI, University of Texas Health Science Center at Houston; Department of Veterans Affairs

Study Staff

LESLIE Y. KWAN, Study Director

ANNE N. STYKA, Senior Program Officer (interim Study Director January–June 2025)

AIMEE MEAD, Program Officer (from October 2024)

NICHOLAS A. MURDOCK, Associate Program Officer (from February 2024)

MAGGIE ANDERSON, Research Assistant (from February 2025)

GRACE READING, Senior Program Assistant (through October 2024)

MIA SALTRELLI, Senior Program Assistant (from April 2025)

Y. CRYSTI PARK, Program Coordinator

ROSE MARIE MARTINEZ, Senior Board Director

Consultants

JOSEPH GASPER, Westat

ANNE ROUBAL, Westat

DELAYNA GOULDING, Westat

RACHEL NEENAN, Westat

CHRIS MANGLITZ, Westat

National Academy of Medicine Fellows

National Academy of Medicine Emerging Leaders in Health and Medicine Scholar

LUCINDA LEUNG, University of California, Los Angeles; VA Greater Los Angeles Healthcare System

National Academy of Medicine Distinguished Nurse Scholar-in-Residence

MARGARET CHAMBERLAIN WILMOTH, University of North Carolina at Chapel Hill

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:

RACHEL SAYKO ADAMS, Boston University

LINDA CHAO, University of California, San Francisco; San Francisco VA Health Care System

JOSEPH T. COYLE, Harvard University

SARA DOLAN, Baylor University

DAVID L. EATON, University of Washington (Emeritus)

ELLEN EISEN, University of California, Berkeley

LAWRENCE GOLDSTEIN, University of California, San Diego

DONGHAI LIANG, Emory University

MELISSA J. PERRY, George Mason University

MARY JO PUGH, University of Utah

CATHERINE M. YORK, Carle Neurosciences Institute

Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the conclusions of

this report nor did they see the final draft before its release. The review of this report was overseen by DAVID A. SAVITZ, Brown University, and KENNETH S. RAMOS, Texas A&M 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.

Acknowledgments

The committee could not have completed its report and accomplished its charge without the critical support of many people. The perspectives of many individuals and groups were immensely helpful to the committee in informing its deliberations through presentations and discussions at the public meetings. These sessions were critical to helping the committee to identify and define relevant exposures and outcomes and appropriate sources of data for its analyses. The following speakers provided their research, expertise, and perspectives: Erin Dursa, Anthony Hardie, Charles Henry, Stuart Hoffman, Chris Ivany, John Kolivosky, Thomas F. Mattras, Tracy Neal-Walden, Ajus Ninan, Chelsey Simoni, Thomas Smoot, Carla Stumpf Patton, and Larry Vandergrift. The committee thanks Aleks Morosky and Jose Ramos at the Wounded Warrior Project for their support connecting the committee with veterans. The committee also greatly benefited from hearing lived experiences and other input from many individuals and organizations on concerns about military exposures and mental health and neurocognitive conditions at its public comment sessions and through written comment.

The committee thanks its Westat consultants, Joseph Gasper, Anne Roubal, DeLayna Goulding, Rachel Neenan, and Chris Manglitz, who provided immense analytic support.

Finally, the committee would like to express its gratitude to the National Academies of Sciences, Engineering, and Medicine staff who contributed to producing this report, especially the dedicated and tireless study staff: Leslie Y. Kwan, Anne Styka, Aimee Mead, Nick Murdock, Maggie

Anderson, Grace Reading, Mia Saltrelli, Y. Crysti Park, and Rose Marie Martinez. The committee is also grateful to Anne Marie Houppert and other National Academies Research Center staff for their assistance with the literature search strategy. The committee thanks Donna Doebler, L. Brielle Dojer, Aja Drain, and Alexandra McKay for their additional support.

Contents

PREFACE

ACRONYMS AND ABBREVIATIONS

SUMMARY

SUMMARY ANNEX: CONCLUSIONS

1 INTRODUCTION

Statement of Task

Committee Process

Committee Approach to Evaluating the Evidence

Organization of This Report

References

2 BACKGROUND AND MILITARY CONTEXT

Factors Before Military Service

Factors During Military Service

Factors During and After Separation from Military Service

Summary

References

3 MILITARY-RELATED ENVIRONMENTAL AND OCCUPATIONAL EXPOSURES

Burn Pits

Dust and PM

Fuels

Exhaust

Incinerator Emissions

Metals

Mold

Radiation

Solvents

Biologic Plausibility and Mechanisms

Summary

References

4 METHODS

Original Data Analyses

Structured Literature Review

Evaluation of Evidence

Summary

References

5 DESCRIPTION OF THE STUDY SAMPLE

Sample Construction

Descriptive Statistics

Exposures

Outcomes

Assessment of Representativeness

Summary

6 RESULTS FOR MENTAL AND BEHAVIORAL HEALTH OUTCOMES

Adjustment Disorders

Attention Disorders

Anxiety Disorders

Depression

Posttraumatic Stress Disorder

Serious Mental Illness: Schizophrenia, Psychosis, and Bipolar Disorder

Sleep Disorders

Substance Use Disorders

Nonfatal Suicide Attempts and Intentional Self-Harm

Summary

References

7 RESULTS FOR NEUROLOGIC OUTCOMES

Amyotrophic Lateral Sclerosis

Dementia

Multiple Sclerosis

Parkinson’s Disease

Summary

References

8 RESULTS FOR CHRONIC MULTISYMPTOM ILLNESS

Chronic Multisymptom Illness

Summary

References

9 CONCLUDING REMARKS

References

APPENDIXES

A Public Law 117-168

B Public Meeting Agendas

C Committee and Staff Biosketches

D ICD-10 Codes for Health Outcomes

E Phecode to ICD-10 Code Mapping

F Comparison of Characteristics of Alternative Study Cohorts

G Odds Ratio Tables

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Boxes, Figures, and Tables

BOXES

S-1 Statement of Task

1-1 Statement of Task

4-1 Health Outcomes

4-2 Exposures from Individual Longitudinal Exposure Record–Exposure Pathway Data

4-3 Structured Literature Search Parameters

FIGURES

2-1 Conceptual model examining factors relevant to the potential relationship between deployment-related environmental and occupational exposures and mental, behavioral, and neurologic health outcomes among post-9/11 U.S. veterans

5-1 Construction of sample for case-control analysis

5-2 Combination heatmap displaying percentage of the population with two overlapping exposures within the sample with each exposure

5-3 Combination heatmap displaying number of the population with two overlapping exposures

Preface

Active-duty military service members are selfless first responders to preserve our national security and that of our allies in times of peace and war. The nation then commits to their support and care following this unquestioned service. Operation Enduring Freedom describes the U.S. military involvement in the war in Afghanistan in the first stage from September 2001 through 2014 and the larger scale of the war through 2021. Operation Iraqi Freedom ran almost concurrently with the conflict in Afghanistan, and these were the largest military operations for the United States since the Vietnam War and the first to rely totally on an all-volunteer force. More than 1.9 million U.S. military personnel have been deployed in 3 million tours of duty lasting more than 30 days as part of these conflicts, enduring recognized and yet-to-be-characterized toxic environmental and occupational exposures in addition to the expected stressors of combat, physical and mental rigors, injuries, and other challenges. Consequences of these experiences often appear years after separation from military service and require identification, characterization, and treatment through clinicians in the Veterans Health Administration and civilian clinical settings.

In accordance with PL 117-168, Sergeant First Class Heath Robinson Honoring our Promise to Address Comprehensive Toxics Act of 2022, this congressionally mandated committee was formed to conduct a study to assess possible relationships between toxic exposures experienced by veterans during military service and mental, behavioral, and neurologic health outcomes and chronic multisymptom illness. The multidisciplinary committee of nationally recognized scientists, statisticians, clinicians, and veterans

offers this report that reflects an independent scientific assessment of and conclusions on the potential relationship between these health conditions and military exposures.

Deborah Cory-Slechta and Jeannette South-Paul, Cochairs

Committee on the Mental Health Effects of Toxic Exposures Among Veterans

August 2025

Acronyms and Abbreviations