Is Rubber Mulch Safe?
Rubber mulch is recycled tire rubber. A 2016 federal status report from the EPA, CDC and the Consumer Product Safety Commission says recycled tire rubber is used in several types of recreational venues, including as loose rubber mulch, as infill in synthetic turf fields and for running surfaces.
The EPA says its July 2019 tire crumb characterization report supports the premise that while chemicals are present in tire crumb rubber as expected, human exposure appears to be limited based on what is released into air or simulated biological fluids. For metals, it says only small fractions, less than 1 to 3 percent, are released into simulated biological fluids, compared with a default assumption of 100 percent.
Zinc is what comes out most. The New York State Department of Health says crumb rubber contains zinc, and that studies consistently find zinc readily leaches from crumb rubber in greater quantities than any other substance.
Sources checked September 15, 2026. Every point below links the page it came from.
The sources behind this answer
- Government sourceA 2016 federal status report says recycled tire rubber is used in several recreational venues, including as synthetic turf infill, as loose rubber mulch or rubber mats, and for running surfaces. US EPA, CDC and CPSC, Federal Research Action Plan status report ↗
- StudyThe EPA says its July 2019 report supports the premise that while chemicals are present in tire crumb rubber, human exposure appears limited based on what is released into air or simulated biological fluids. US EPA ↗
- StudyThe EPA says only small fractions of metals, less than 1 to 3 percent, are released from tire crumb rubber into simulated biological fluids, compared with a default assumption of 100 percent. US EPA ↗
- Government sourceThe New York State Department of Health says crumb rubber contains zinc, and studies consistently find zinc readily leaches from crumb rubber in greater quantities than any other substance. New York State Department of Health ↗
Sources checked September 15, 2026. A brand statement is the company’s own claim, which we report but have not verified. Our grades are model-based estimates, not lab tests.