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International Standard Book Number-13: 978-0-309-70011-5
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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2023. Health Risk Considerations for the Use of Unencapsulated Steel Slag. Washington, DC: The National Academies Press. https://doi.org/10.17226/26881.

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COMMITTEE ON ELECTRIC ARC FURNACE SLAG: UNDERSTANDING HUMAN HEALTH RISKS FROM UNENCAPSULATED USES

Members

AARON BARCHOWSKY(Chair), University of Pittsburgh, Pittsburgh, PA

MICHAEL ASCHNER, Albert Einstein College of Medicine, Bronx, NY

DANIEL BAIN, University of Pittsburgh, Pittsburgh, PA

SIMONE CHARLES, University of Michigan, Ann Arbor, MI

ALAN CRAMB, Illinois Institute of Technology, Chicago, IL

NATASHA DEJARNETT, University of Louisville, Louisville, KY (until November 21, 2022)

REBECCA FRY, University of North Carolina, Chapel Hill, NC

PHILIP GOODRUM, GSI Environmental Inc., Fayetteville, NY

JOHN KISSEL, University of Washington, Seattle, WA

DEB NIEMEIER, University of Maryland, College Park, MD

PEGGY O’DAY, University of California, Merced, CA

RUTH O’DONNELL, Private citizen, Waukesha, WI

REBECCA PARKIN, The George Washington University, Washington, DC

DAVID WALKER, Columbia University, Palisades, NY

ROBERT WRIGHT, Icahn School of Medicine at Mount Sinai, New York, NY

Staff

RAYMOND WASSEL, Scholar and Responsible Staff Officer

CLIFFORD S. DUKE, Director, Board on Environmental Studies and Toxicology

KATHRYN GUYTON, Senior Program Officer (until May 2, 2023)

NATALIE ARMSTRONG, Associate Program Officer (until December 20, 2022)

ANTHONY DEPINTO, Associate Program Officer

LESLIE BEAUCHAMP, Senior Program Assistant

THOMASINA LYLES, Senior Program Assistant

Sponsor

U.S. ENVIRONMENTAL PROTECTION AGENCY

BOARD ON ENVIRONMENTAL STUDIES AND TOXICOLOGY

Members

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

DANA BOYD BARR, Emory University, Atlanta, GA

ANN M. BARTUSKA, U.S. Department of Agriculture (retired), Washington, DC

WEIHSUEH A. CHIU, Texas A&M University, College Station, TX

FRANCESCA DOMINICI, Harvard University, Boston, MA

MAHMUD FAROOQUE, Arizona State University, Tempe, AZ

R. JEFFREY LEWIS, ExxonMobil Biomedical Sciences, Inc., Annandale, NJ

MARIE LYNN MIRANDA, University of Notre Dame, Notre Dame, IN

MELISSA J. PERRY, George Mason University, Fairfax, VA

REZA J. RASOULPOUR, Corteva Agriscience, Indianapolis, IN

JOSHUA TEWKSBURY, Smithsonian Tropical Research Institute, Panamá

SACOBY M. WILSON, University of Maryland, College Park, MD

TRACEY JEAN WOODRUFF, University of California, San Francisco, CA

Staff

CLIFFORD S. DUKE, Director

RAYMOND WASSEL, Scholar

KATHRYN GUYTON, Senior Program Officer

NATALIE ARMSTRONG, Associate Program Officer

ANTHONY DEPINTO, Associate Program Officer

LAURA LLANOS, Finance Business Partner

LESLIE BEAUCHAMP, Senior Program Assistant

THOMASINA LYLES, Senior Program Assistant

KATHERINE KANE, 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:

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 L. EATON (NAM), University of Washington, and CORALE L. BRIERLEY (NAE), Brierley Consultancy LLC. 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.

Contents

ACRONYMS AND ABBREVIATIONS

SUMMARY

1INTRODUCTION

Steelmaking and Electric Arc Furnace Slag

Study Background

Committee’s Statement of Task and Approach

Organization of the Report

2ELECTRIC ARC FURNACE STEELMAKING AND SLAG FORMATION, COMPOSITION, AND DISTRIBUTION

Steel Production and Slag Formation in an Electric Arc Furnace

Slag Composition

Slag Processing, Distribution, and Use

Geographic Distribution of Electric Arc Furnace Facilities and Slag Processors

State Government Oversight of Slag Use

Summary

3PROPERTIES AND ENVIRONMENTAL DYNAMICS OF SLAG

Mineralogy and Mineralogical Phases of Slag Solidification

Trace Constituents in Slag

Organic Pollutants from Plastic Materials Mixed with Scrap Steel

Weathering and Mechanical Degradation of Slag

Environmental Weathering of Slag

Mechanical Degradation of Slag

Release and Environmental Transport of Trace Slag Constituents

Leaching and Mobilization of Trace Elements by Water

Summary

4HUMAN EXPOSURE TO UNENCAPSULATED ELECTRIC ARC FURNACE SLAG

Conceptual Site Model

Average Daily Dose Equations

Bioaccessibility and Bioavailability

Key Exposure Variables for Further Evaluation

Summary

5TOXICITY OF SELECTED SLAG CONSTITUENTS

Chromium

Manganese

Summary

6MULTIPLE STRESSORS IN DISADVANTAGED COMMUNITIES WHERE UNENCAPSULATED SLAG MAY BE USED

Cumulative Exposures

Societal Inequities and Cumulative Exposures

Demographic Considerations

Summary

7SYNTHESIS OF RISK CONSIDERATIONS FOR UNENCAPSULATED ELECTRIC ARC FURNACE SLAG USES

Previous Risk Assessments on Electric Arc Furnace Slag

Hazard Ranking of Constituents in Electric Arc Furnace Slag

Risk Factors and Data Needs

Priority Research Needs

REFERENCES

APPENDIXES

ACOMMITTEE MEMBER BIOGRAPHIES

BOPEN SESSION AGENDAS

CEAF STEEL FACILITIES

DSLAG PROCESSING FACILITIES

ESLAG MINERALOGY

FREVIEW OF PAST RISK ASSESSMENTS OF ELECTRIC ARC FURNACE SLAG

Acronyms and Abbreviations