Research into Utilization of Repurposed Tire Granules on Sports Fields and Playgrounds by Federal Institutions
The Federal Research Action Plan (FRAP) on Recycled Tire Crumb Used on Playing Fields and Playgrounds, a collaborative effort launched in 2016 by the Centers for Disease Control and Prevention (CDC), the Agency for Toxic Substances and Disease Registry (ATSDR), the U.S. Consumer Product Safety Commission (CPSC), and other agencies, has released its findings.
The FRAP aimed to fill data and knowledge gaps, characterize constituents of tire crumb, and identify ways people may be exposed to tire crumb rubber. The study had four parts: Literature Review/Gap Analysis, Recycled Tire Crumb Characterization, Exposure Characterization Study, and Playground Study.
The Recycled Tire Crumb Characterization Report, released in 2019, found that a range of metals, semivolatile organic compounds, volatile organic compounds, and bacteria were detected in recycled tire crumb rubber infill. However, for many chemicals measured during active play at the outdoor fields, concentrations in air were not different than background samples while others were somewhat higher.
The Exposure Characterization Study, completed in 2024, found no differences in PAH metabolites in urine between study participants using synthetic turf fields compared to those using grass fields. However, it did find that many chemicals were found at higher concentrations in air samples at the indoor field compared to the outdoor fields.
The Playground Study, conducted by the CPSC and completed in 2019, gathered information about children's behavior on playgrounds. A report of the survey findings is available.
The Tire Crumb Exposure Characterization Report, also finalized in 2024, provided further details on potential exposures for those who use turf fields containing tire crumb. The CPSC will use both the FRAP Report Part 1 and Part 2 in its work on playgrounds, conducting a risk assessment of children's exposure to playground surfaces made of tire rubber.
In the biomonitoring pilot study, concentrations for metals measured in blood were similar to those in the general population. The study found that generally, only small amounts of most organic chemicals are released from tire crumb into the air through emissions.
The FRAP found no definitive evidence of serious health risks associated with exposure to recycled tire crumb rubber on synthetic turf fields. However, it emphasized that significant questions and uncertainties remain about potential long-term health effects, warranting further study.
In summary, while current evidence from the federal research initiative does not confirm significant health hazards from tire crumb on play surfaces, the plan calls for ongoing monitoring and more comprehensive research to resolve remaining uncertainties about safety. This cautious but largely reassuring conclusion aligns with other recent assessments noting the sustainability benefits of crumb rubber recycling alongside the need for vigilance on potential health impacts.
For more information, the Synthetic Turf Field Recycled Tire Crumb Rubber Characterization Research Final Report: Part 1 - Tire Crumb Rubber Characterization is now available for access and download. Tire Crumb Rubber Questions and Answers are also available. A summary of public and stakeholder engagement for the FRAP is also available. A public webinar on August 6th, 2019, was given to learn more about the Tire Crumb Rubber Characterization (Part 1) Report. The Recycled Tire Crumb Rubber Exposure Characterization Report was finalized and released by EPA and ATSDR in April 2024, completing their work with respect to playing fields. The EPA and ATSDR also completed a pilot-scale exposure study that included the collection of indoor and outdoor field, personal, and biomarker samples for indicators of exposures, questionnaire and video-based activity assessments, and exposure modeling assessments.
- The study under the Federal Research Action Plan (FRAP) aimed to understand exposure to tire crumb rubber, investigating different chemicals such as metals, semivolatile organic compounds, volatile organic compounds, and bacteria in the air and playground surfaces.
- The Exposure Characterization Study uncovered higher concentrations of chemicals in air samples at indoor fields compared to outdoor fields, signifying a potential concern for environmental science and health-and-wellness.
- Although the FRAP findings did not confirm significant health hazards from tire crumb on play surfaces, it emphasized the necessity for continuous monitoring and extensive research in environmental science, medical-conditions, health-and-wellness, and science to address any remaining safety concerns.
