The Facts & Science on Recycled Rubber
Questions & Answers about Recycled Rubber
- What is crumb rubber?
Crumb rubber is a granular recycled rubber particle that is made from repurposed tires. End-of-use rubber tires go through a cleaning and grinding process, which creates a material that has the same chemical composition as the rubber we use in our everyday lives. The condensed spongy granular output is ideal for filling field and playground surfaces. In short, crumb rubber is a form of recycled rubber, which is simply rubber.
- Why should we be recycling scrap tires?
Tire recycling is an economically sound, environmentally-friendly activity that contributes to a significant reduction of a tire's overall carbon footprint.
- Is crumb rubber safe?
Yes. There are more than 110 technical studies conducted by academic, private, and government entities that have found little or no significant health risk.
- Is crumb rubber a better material for athletic surfaces?
Crumb rubber infill and surfaces perform better than grass fields by enabling twice the amount of playing time, and an extended lifespan with proper maintenance. Whereas grass fields can lose significant playing time during the spring and fall due to rain, and during winter due to snow.
Turf fields with crumb rubber have a higher degree of surface friction and are more shock-absorbent than grass. This means that players are less likely to slip or fall unexpectedly on crumb rubber surfaces, but if they do, their impact will be more evenly distributed and less severe.
- Are there other types of infills for synthetic turf fields?
Crumb rubber is not the only type of infill used in turf fields. Ground cork, walnut shells, and coconut husks – to name a few- are other infill materials.
- Are soccer players and other athletes that play on synthetic turf more susceptible to health risks?
No. Dr. Archie Bleyer, former Chair of the Children's Cancer Group, the world's largest pediatric cancer research organization, tested soccer players in Washington state in 2017. He found that " Regular physical activity during adolescence and early adulthood helps prevent cancer later in life. Restricting the use or availability of all-weather year-round synthetic fields and thereby potentially reducing exercise could, in the long run, actually increase cancer incidence, as well as cardiovascular disease and other chronic illnesses."
- Why is the federal government studying crumb rubber if it's been found to be safe?
The EPA, CDC, and CPSC have been engaged in a multi-agency four-part research effort, titled "Federal Research Action Plan on Recycled Tire Crumb Used on Playing Fields and Playgrounds," since 2016. The goal of the study is to fill any potential data and knowledge gaps, characterize constituents of crumb rubber, and identify ways where people might encounter crumb rubber.
So far, the literature review and characterization study have been released, producing similar findings to past studies – crumb rubber presents no significant health risk.
- What exactly is being made from crumb rubber?
Recycled rubber is being used by manufacturers in a wide variety of applications today, including in agriculture, flooring, landscaping, infrastructure, and sports.
- How does this impact the environment?
Recycling rubber tires means that millions of scrap tires are no longer dumped in landfills, or left illegally in lakes, abandoned lots, along the side of the road and in sensitive habitats.
- How does crumb rubber infill compare to soil?
Both crumb rubber and surface soil contain naturally occurring elements and metals. Crumb rubber contains very low levels of these elements and metals, and it is not uncommon for background soil to contain higher levels due to historic pollution.
Studies Addressing Safety
To date, there have been more than 110 scientific studies, including peer-reviewed academic analyses and federal and state government reports that have thus far found no significant health risk associated with artificial (synthetic) turf with recyclable rubber infill.
We've highlighted some recent studies below.
Environmental Research: A research team published a January 2018 study in Environmental Research on their human health risk assessment of exposure to chemicals found in recycled rubber. They found that all estimated exposure risk scenarios fell within EPA guidelines, and that cancer levels for synthetic turf field users were comparable to or lower than those associated with natural soil fields.
Sports Medicine: Dr. Archie Bleyer published a May 2017 study in Sports Medicine to test public perceptions regarding the carcinogenic effects of crumb rubber exposure. Bleyer found that the state of adolescent cancer causation research does not support that claim and concluded that decreasing exercise by reducing access to playgrounds and sports fields may actually increase the rate of cancer occurrence among children in later life.
Washington State Department Of Health: The Washington State Department of Health published an April 2017 study to test unsubstantiated claims that soccer goalkeepers were more likely to get cancer due to high levels of crumb rubber exposure. The study compared cancer rates of soccer players to the general public, and assessed other carcinogenic factors associated with the demographic of the soccer players identified. It found that the players identified actually had lower rates of cancer compared to peer groups.
European Chemicals Agency: The European Chemicals Agency published a February 2017 study based on concerns from European Commission members. The study evaluated the risks to human health from substances found in recycled rubber granules that are used as an infill material in synthetic turf. ECHA found no reason to advise people against playing sports on synthetic turf containing recycled rubber granules as infill material, based on finding a very low level of concern from exposure to substances found in rubber granules.