The OEHHA report found “no evidence of significant risk for cancer or other health problems” tied to crumb rubber exposure for players, coaches, referees and spectators, including young athletes. | Photo Credit: Robert A. Bothman Inc.
What You Need to Know
- California’s Office of Environmental Health Hazard Assessment (OEHHA) released a final study assessing potential health risks from recycled-tire “crumb rubber” used as synthetic turf infill.
- OEHHA reported no evidence of a significant risk of cancer or other health problems for athletes, coaches, referees, or spectators — including young athletes and toddlers.
- The nine-year effort evaluated 35 fields across California, analyzed 100+ chemicals, and included air sampling plus exposure research involving 1,000+ soccer players.
- OEHHA said the findings may help inform California sustainability and waste-tire management goals as synthetic turf use expands statewide.
Learn More
SACRAMENTO, Calif. — California’s Office of Environmental Health Hazard Assessment has concluded that crumb rubber infill made from recycled tires is not likely to pose a significant health risk to people who use or watch games on synthetic turf fields.
In a March 5 press release, OEHHA said its final report found “no evidence of significant risk for cancer or other health problems” tied to crumb rubber exposure for players, coaches, referees and spectators, including young athletes.
The assessment focused on crumb rubber, the small granules produced by grinding recycled waste tires and commonly used as infill between synthetic grass blades. OEHHA said the material helps keep turf fibers upright, adds cushioning and improves traction.
“This study should ease concerns about the safety of crumb rubber use in synthetic turf fields,” said OEHHA Director Kris Thayer, “Athletes of all ages can use these fields without parents worrying about this commonly used material,” according to an OEHHA press release.
OEHHA said synthetic turf is widely used because it requires less maintenance, uses less water and can support play without rest periods. The agency cited more than 900 synthetic turf installations in California.
The report was also framed as part of California’s broader waste-tire and sustainability efforts.
“Protecting public health is our top priority, and California is committed to making sure waste tires are managed safely so they don’t litter communities or pose risks to residents,” CalRecycle Director Zoe Heller said, according to an OEHHA press release.
To evaluate potential health impacts, OEHHA tested 35 synthetic turf fields across the state, selecting both older and newer sites and including locations from each of California’s climate regions. The agency collected multiple samples from each field to address variation in source materials and also took air samples during active field use and when fields were idle.
OEHHA said it assessed more than 100 chemicals that could pose a risk, a broader scope than prior studies that reviewed fewer compounds. The agency coordinated with Lawrence Berkeley National Laboratory to simulate sweat and digestion as part of identifying chemicals people could potentially contact.
OEHHA also worked with researchers from UC Berkeley and the University of Arizona to examine how soccer players may be exposed — including through skin contact, inhalation and incidental ingestion. The team surveyed more than 1,000 soccer players ages 7 to 71 about play habits such as sliding and diving, and recorded games and practices to quantify field contact. Because goalkeepers tend to have the most contact with the surface, OEHHA said goalie data were used to estimate risk for players. The analysis also considered toddlers who might crawl on turf.
In its risk characterization, OEHHA reported no acute risk for athletes, referees, coaches or spectators, including toddlers. In most cases, the agency said risks of sensory irritation, cancer, reproductive harm or effects on a developing fetus were “negligible.”
This article is based on reporting originally published by the California Office of Environmental Health Hazard Assessment (OEHHA) on March 5, 2026.