Federal Research on Recycled Tire Crumb Used on Playing Fields
Concerns have been raised by the public about the potential health risks from playing on synthetic turf fields in the U.S. containing tire crumb rubber. Studies to date have not shown an elevated health risk from playing on fields with tire crumb rubber, but the existing studies have been limited.
To help address these concerns, the Centers for Disease Control and Prevention/Agency for Toxic Substances and Disease Registry (CDC/ATSDR) and the U.S. Environmental Protection Agency (EPA), in collaboration with the Consumer Product Safety Commission (CPSC), launched a multi-agency research effort in February 2016.
This multi-agency research effort, known as the Federal Research Action Plan on Recycled Tire Crumb Used on Playing Fields and Playgrounds (FRAP), is focused on assessing potential human exposure, which includes conducting research activities to characterize the chemicals associated with tire crumb rubber and to identify the ways in which people may be exposed to those chemicals based on their activities on synthetic turf fields. Also, the FRAP includes characterizing emissions and bioaccessibility to differentiate what is present in the tire crumb rubber from what people may actually be exposed to from tire crumb rubber.
This coordinated Federal Research Action Plan on Recycled Tire Crumb Used on Playing Fields and Playgrounds (FRAP) includes outreach to key stakeholders, such as athletes and parents, and seeks to:
- Fill important data and knowledge gaps.
- Characterize constituents of tire crumb.
- Identify ways in which people may be exposed to tire crumb rubber based on their activities on the fields.
The study has four parts:
- Literature Review/Gap Analysis (EPA and CDC/ATSDR)
- Recycled Tire Crumb Characterization (EPA and CDC/ATSDR)
- Exposure Characterization Study (EPA and CDC/ATSDR)
- Playground Study (Consumer Product Safety Commission)
Based upon available literature, this research effort represents the largest tire crumb rubber study conducted in the United States. While this report is not a risk assessment, the information and results from the effort will fill specific data gaps about the potential for human exposure to chemical constituents associated with tire crumb rubber used in synthetic turf fields. In general, the findings from the report support the premise that while chemicals are present as expected in the tire crumb rubber, human exposure appears to be limited based on what is released into air or simulated biological fluids (gastric fluid, saliva and sweat).
Currently, CDC/ATSDR is initiating a biomonitoring study to investigate potential exposure to constituents in tire crumb rubber. The CDC/ATSDR 30-day Federal Register Notice inviting comments on the information collection request, "Exposure Characterization and Measurements during Activities Conducted on Synthetic Turf Fields with Tire Crumb Rubber Infill,"EXIT has now closed.
The exposure characterization report (Part 2) will summarize the potential exposures that may be experienced by users of synthetic turf playing fields with tire crumb rubber, such as how people come in contact with the materials, how often and for how long. Part 2 will be released at a later date, along with results from the planned biomonitoring study conducted by CDC/ATSDR. The timeline and information about the study will continue to be posted to this website.
Literature Review/Gap Analysis (EPA and CDC/ATSDR): On December 30, 2016, the agencies released a status report describing the progress of the research to date. The status report includes the final peer-reviewed Literature Review/Gaps Analysis report and describes the progress to date on other research activities that are part of the effort including: Characterization of the chemicals found in tire crumb rubber; Characterization of the exposure scenarios for those who use turf fields containing tire crumb rubber; Study to better understand how children use playgrounds containing tire crumb and; Outreach to key stakeholders. The status report does not include research findings. (See sidebar for links to the Federal Register Notices and 2016 Status Report).
Recycled Tire Crumb Characterization (EPA and CDC/ATSDR): Tire crumb rubber samples were gathered from tire crumb manufacturing/recycling plants and from indoor and outdoor fields across the country. Samples were gathered from nine tire crumb manufacturing/recycling plants and 40 fields. Collection and analysis of the samples for the tire crumb characterization portion of the study was completed in 2018. A draft report of results was sent for external peer-review in May 2018. The report is now available to view here (or in the link on the sidebar).
Exposure Characterization Study (EPA and CDC/ATSDR): The exposure characterization pilot portion of the study as outlined in the Federal Research Action Plan was posted for public comment in February 2017. An additional requirement of a 30-day Federal Register Notice, along with the Information Collection Request (ICR) package was published on June 12, 2017. On August 2, 2017, the Office of Management and Budget (OMB) approved the Information Collection Request for the continuation of the exposure characterization study. With the OMB approval, the EPA and CDC/ATSDR team were able to complete the field work associated with the exposure characterization in the Fall of 2017. During the exposure characterization field work, EPA and CDC/ATSDR visited several fields to collect exposure information to better characterize people’s exposure to tire crumbs. Activity information from field users who elected to participate in the study was also gathered. Analysis of the samples for the exposure characterization portion of the study was completed in 2018. A draft report of results was sent for external peer-review in May 2018. Peer review of the draft study (both characterization and exposure components) identified weaknesses in the human exposure study. As a result, CDC determined it needed to conduct a more robust biomonitoring study to investigate potential exposure to constituents in tire crumb rubber. This new study required a new ICR and expanded the timeline. The decision was made to not hold off on releasing the characterization part of the study (Synthetic Turf Field Recycled Tire Crumb Rubber Characterization Research Final Report: Part 1 -Tire Crumb Rubber Characterization).
Playground Study (Consumer Product Safety Commission): CPSC conducted a playground use survey gathering information about children’s behavior on playgrounds. This survey has been completed and is currently being reviewed by CPSC staff. It could be released as early as fall 2019. CPSC will continue its work on playgrounds by conducting a risk assessment of children’s exposure to playground surfaces made of recycled tire rubber. This work will utilize the CPSC survey as well as data from EPA’s FRAP Part 1 (characterization of the chemicals and materials in recycled tire rubber crumb), released July 25, and CDC’s (ATSDR) FRAP Part 2 (characterization of potential exposures for those who use turf fields containing tire crumb) after it is released.