Crumb rubber or another infill for a sports field?

What the federal study found

In February 2016, CDC/ATSDR and the EPA, working with the Consumer Product Safety Commission, launched the Federal Research Action Plan on tire crumb used on playing fields. The EPA calls it the largest tire crumb rubber study conducted in the United States. It reported in two parts.

Part 1, July 2019, asked what is in the rubber. As expected, it detected a range of metals, semivolatile and volatile organic compounds, and bacteria. The team sampled 40 fields, 25 outdoor and 15 indoor, plus material from nine tire recycling plants, according to New Jersey’s environment department, which summarized both parts in October 2025.

Part 2, April 2024, asked what reaches people during play. It used skin wipes, air, dust and field surface samples, plus a small blood and urine study. Taken together, EPA says the findings show chemicals are present and exposures can occur, but “they are likely limited.” Its examples:

• Only small amounts of most organic chemicals are released from the rubber into the air.
• Less than 1 to 3 percent of the metals dissolved into simulated body fluids.
• Metals in blood were similar to those in the general population.
• PAH markers in urine did not differ between players on turf and players on grass.

What the study did not settle

Know the limits before you quote the results to a board or a parent group.

• It is not a risk assessment. EPA says so in its questions and answers.
• The blood and urine work was a pilot. New Jersey counts 25 participants, with 14 urine and 13 blood samples from outdoor play. One naphthalene marker ran 34 percent higher after play, though New Jersey says it is hard to conclude the turf was the main source.
• Only the rubber was tested. Part 1 left out the turf blades, the backing, and other infills such as sand and coconut fiber.
• Playgrounds are still open. EPA’s page, checked 12 September 2026, says the CPSC will go on to a risk assessment of children’s exposure to playground surfaces made of tire rubber.

Indoor fields need their own plan

The federal team found many chemicals at higher concentrations in the air at the indoor field than at the outdoor fields. In the Part 1 rubber samples, New Jersey reports indoor levels of semivolatile compounds 1.5 to 10 times higher than outdoor, possibly because indoor rubber sees less sun and rain, and less ventilation.

Connecticut’s Department of Public Health advises indoor fields to increase ventilation as much as possible. For an indoor facility, plan the air handling alongside the infill.

The alternatives, side by side

The Toxics Use Reduction Institute at UMass Lowell sorts the alternatives into three groups:

• Synthetic: EPDM, TPE, and products made from waste athletic shoe materials.
• Mineral or plant-based: sand, cork and coconut hulls.
• Combinations: such as acrylic-coated sand.

TPE (thermoplastic elastomer). TURI’s TPE assessment concludes that, on the information available, TPE “contains fewer chemicals of concern” than tire crumb, but is still likely to contain some. TPE is a broad family, and products vary. TURI also heard from a municipality whose infill was labeled TPE but was made from PVC plastic. Confirm the polymer in writing.

EPDM. TURI’s EPDM assessment finds it “may contain fewer chemicals of concern” than tire crumb, again with some present. New Jersey cites evidence of lower PAHs and metals in water leached from EPDM. Read spec sheets closely: tire crumb can itself be coated with EPDM, and coated crumb is still tire rubber underneath.

Cork, coconut and walnut shell. These avoid rubber altogether. New Jersey found no extensive scientific study of the health effects of substitute infills. It flags that walnut shells or coconut may pose a risk to players with food allergies.

Sand, coated sand and zeolite. Rubber pellets are buoyant and may wash away, New Jersey warns. Where significant rain events are common, it advises high-specific-gravity infills such as silica or acrylic-coated sand and zeolite-based infill. If your field takes heavy storms, weigh this one heavily.

On environmental footprint the picture flips back and forth. In one life-cycle comparison New Jersey cites, tire crumb came out ahead of virgin TPE, EPDM and recycled EPDM. Bio-based infills such as cork, olive pits, wood granulate and coconut fiber may be the most favorable of all.

Heat: infill changes it less than you’d think

Infill alone won’t make a field cool. TURI’s hazards assessment states that “all synthetic turf reaches higher temperatures than natural grass, regardless of the infill materials.” One study it cites measured lower temperatures with TPE infill than with tire crumb or plant-based infill.

Plan for heat whichever infill you pick. Connecticut’s health department notes that crumb rubber absorbs heat, and advises more frequent rest breaks and more water for players.

Microplastics, and a date in Europe

Tire crumb pieces are typically less than 5 mm across, which makes them microplastics by definition, New Jersey notes. Europe’s chemicals agency estimates about 16,000 tons of infill lost each year in Europe, roughly 900 kg per field.

The EU has acted. Under Regulation (EU) 2023/2055, the ban on selling granular infill for synthetic sports surfaces applies from 17 October 2031, according to the European Commission.

That is an EU rule. For a U.S. field, the rules to check are your state’s and your local government’s. Florida’s turf rule, for example, covers only single-family lots of an acre or less, and Florida DEP says it does not apply to athletic fields. Our Florida infill guide explains the residential side.

What to tell parents

Connecticut’s health department lists simple habits for players on crumb rubber fields:

• wear shoes on the field;
• don’t swallow infill, and watch young children;
• wash hands after play, especially before eating;
• clean turf burns with soap and water;
• clean clothing and equipment after use;
• take shoes off before going into the house.

The department also says it does not endorse any consumer product, artificial turf included. EPA suggests checking your own state’s public health agency for state-specific advice.

Checklist for your infill specification

For a new field or a replacement, our sports field turf page covers the work. On a free visit we measure the field and check the ground, then draw a custom layout you approve. Settle these first:

1. Name the problem you’re solving: chemicals, heat, storm washout or allergies.
2. Get the polymer and its additives in writing. TURI notes the full additive list is often not disclosed.
3. For TPE, confirm it isn’t PVC.
4. Ask which test standard the product data was checked against.
5. Where storms are heavy, favor an infill that won’t float.
6. Indoors, plan ventilation with the surface.
7. Plan heat breaks and closures for any infill.
8. Schedule grooming and decompaction to keep infill depth, and test hardness yearly, as in how long a turf field lasts.
9. Check your state health agency and local rules before you order.