Understanding the Impacts of Tire Anti-Degradants 6PPD and 6PPD-Quinone on Airports (2026)
Chapter: Front Matter
Understanding the Impacts of
Tire Anti-Degradants
6PPD and 6PPD-Quinone on
Airports
Christine Nancarrow
Selene Convy
Pacific Stormwater
Seattle, WA
Christopher D. Zevitas
Jacob Klaybor
U.S. DOT Volpe National Transportation Systems Center
Cambridge, MA
 |
Conduct of Research Report for ACRP 11-09 Topic 02 Submitted July 2026 |
ACRP Web-Only Document 69
Understanding the Impacts of Tire Anti-Degradants
6PPD and 6PPD-Quinone on Airports
© 2026 by the National Academy of Sciences. National Academies of Sciences, Engineering, and Medicine and the graphical logo are trademarks of the National Academy of Sciences. All rights reserved.
ACKNOWLEDGMENT
This work was sponsored by the Federal Aviation Administration (FAA). It was conducted through the Airport Cooperative Research Program (ACRP), which is administered by the Transportation Research Board (TRB) of the National Academies of Sciences, Engineering, and Medicine.
COPYRIGHT INFORMATION
Authors herein are responsible for the originality and accuracy of their materials and for obtaining written permissions from publishers or persons who own the copyright to any previously published or copyrighted material used herein.
The National Academy of Sciences (NAS) grants permission to reproduce written material in this publication for classroom and non-commercial purposes subject to the rights of any third parties and appropriate attribution. Permission is given with the understanding that none of the material will be used to imply NAS, TRB, AASHTO, APTA, FAA, FHWA, FTA, GHSA, or NHTSA endorsement of a particular product, method, or practice. For other uses of the written material, users must request permission from the National Academies Press.
DISCLAIMER
Any opinions, findings, and conclusions or recommendations expressed or implied in this document are those of the researchers who performed the research and are not necessarily those of the Transportation Research Board; the National Academies of Sciences, Engineering, and Medicine; or the program sponsors.
The Transportation Research Board does not develop, issue, or publish standards or specifications. The Transportation Research Board manages applied research projects which provide the scientific foundation that may be used by Transportation Research Board sponsors, industry associations, or other organizations as the basis for revised practices, procedures, or specifications.
The Transportation Research Board, the National Academies, and the sponsors of the Airport Cooperative Research Program do not endorse products or manufacturers. Trade or manufacturers’ names appear herein solely because they are considered essential to the object of the report.
The information contained in this document was taken directly from the submission of the author(s). This material has not been edited by TRB.
The National Academy of Sciences was established in 1863 by an Act of Congress, signed by President Lincoln, as a private, nongovernmental institution to advise the nation on issues related to science and technology. Members are elected by their peers for outstanding contributions to research. Dr. Neil Shubin is president.
The National Academy of Engineering was established in 1964 under the charter of the National Academy of Sciences to bring the practices of engineering to advising the nation. Members are elected by their peers for extraordinary contributions to engineering. Dr. Tsu-Jae Liu is president.
The National Academy of Medicine (formerly the Institute of Medicine) was established in 1970 under the charter of the National Academy of Sciences to advise the nation on medical and health issues. Members are elected by their peers for distinguished contributions to medicine and health. Dr. Monica Bertagnolli is president.
The three Academies work together as the National Academies of Sciences, Engineering, and Medicine to provide independent, objective analysis and advice to the nation and conduct other activities to solve complex problems and inform public policy decisions. The National Academies also encourage education and research, recognize outstanding contributions to knowledge, and increase public understanding in matters of science, engineering, and medicine.
Learn more about the National Academies of Sciences, Engineering, and Medicine at www.nationalacademies.org.
The Transportation Research Board is one of four centers of the National Academies of Sciences, Engineering, and Medicine. The mission of the Transportation Research Board is to mobilize expertise, experience, and knowledge to anticipate and solve complex transportation-related challenges. The Board’s varied activities annually engage more than 5,500 engineers, scientists, and other transportation researchers and practitioners from the public and private sectors and academia, all of whom contribute their expertise in the public interest. The program is supported by state departments of transportation, federal agencies including component administrations of the U.S. Department of Transportation, and other organizations and individuals interested in the development of transportation.
Learn more about the Transportation Research Board at www.TRB.org.
COOPERATIVE RESEARCH PROGRAMS
CRP STAFF FOR ACRP WEB-ONLY DOCUMENT 69
Monique R. Evans, Director, Cooperative Research Programs
Waseem Dekelbab, Deputy Director, Cooperative Research Programs
Jordan Christensen, Senior Program Manager
Demisha Williams, Senior Program Assistant
Brian Haefs, Acting Director of Publications
Jennifer Correro, Assistant Editor
ACRP PROJECT 11-09/Topic 02 PANEL
Field of Special Projects
Api Appulingam, City of Philadelphia, PA, Philadelphia, PA
Steven L. Domino, InterVISTAS, San Mateo, CA
Kimberly A. Kenville, University of North Dakota, West Fargo, ND
Rohini Kumarage, City of Austin, TX, Austin, TX
Carol L. Niewola, New Hampshire Department of Transportation, Concord, NH
Angel E. Ramos, AtkinsRealis, Brownsville, TX
Cedric Simon, Lynchburg Regional Airport, Lynchburg, VA
Asciatu Whiteside, Dallas-Fort Worth International Airport, DFW Airport, TX
Elissa Ashley, FAA Liaison
Rachel Stephenson, FAA Liaison
Melinda Z. Pagliarello, Airports Council International–North America Liaison
CONTENTS
2 WHAT ARE TIRE ANTI-DEGRADANTS AND WHAT IS THE CONCERN? BACKGROUND ON TIRE ANTI-DEGRADANTS
2.1 What Are Tire Anti-Degradants 6PPD and 6PPD-q?
2.2 Why Are 6PPD and 6PPD-q a Concern?
3 SOURCES AND PATHWAYS AT AIRPORTS
3.2 Crumb Rubber in Recycled Tire Asphalt
4 ENVIRONMENTAL AND OPERATIONAL IMPACTS
5 REGULATORY AND LEGAL CONTEXT
5.1 Federal, State, Tribal, and International Policy and Regulatory Developments
6 MITIGATION AND MANAGEMENT STRATEGIES
6.1 Development of Alternative Tire Anti-Degradants
6.2 Conventional Airport Design Mitigation Opportunities and Alternatives to Recycled Tire Asphalt
6.3 Conventional Stormwater Best Management Practices
6.4 Innovative Stormwater Best Management Practices
6.5 Enhanced FOD and Runway Rubber Removal
6.6 Waste Management and Disposal
7 CURRENT AIRPORT RESEARCH AND FUTURE RESEARCH NEEDS
7.1 Completed and Ongoing Research Conducted at Airports
