Is Crumb Rubber Safe? Bill Seeks to Answer That Troubling Question

This story has been published in tandem with a segmentfor KCET's award-winning TV show "SoCal Connected." Watch it here now.

Sen. Jerry Hill (D-San Mateo) was struck by the scent of an artificial athletic field at a San Mateo County probation facility: rubber. "You can smell rubber. And when you walk on it these little clouds come up," Hill said. "You're obviously ingesting that, you're breathing it, if you get a cut it gets in your skin."

Hill joins parents and athletes across California who look at the artificial soccer, football, and baseball fields beneath their children's or their own feet, and ask: Is that stuff safe?

Over the past decade or so, synthetic materials have largely replaced natural grass on playing fields in public and private schools, parks, and professional stadiums. And while artificial turf comes in many varieties, the concern mostly lies with crumb rubber: small particles of shredded car and truck tires. The rubber crumbs, about the size of bread crumbs, are spread between blades of fake grass to act as a kind of synthetic dirt. They provide cushioning and grip.

But car and truck tires can contain a host of toxins, including carcinogens and heavy metals on the state's own Proposition 65 list of substances that cause cancer or reproductive harm.

SB 47, a new bill introduced by Hill, aims to find an answer to the looming safety question. The Children's Safe Playground and Turf Field Act of 2015, introduced on Dec. 17, would place a moratorium on the installation of crumb rubber fields by public or private schools or local governments until 2018. The bill calls for the Office of Environmental Health Hazard Assessment to study crumb rubber in the meantime. The bill could be assigned to a committee as early as Jan. 17.

"The Los Angeles Unified School District and New York City have already implemented complete bans -- this is just a temporary moratorium until a thorough analysis can be conducted," Hill said in a press release.

"Concerns have mounted about chemical compounds contained in recycled rubber tires as an increasing number of young athletes have developed leukemia, non-Hodgkin lymphoma, and testicular, prostate, and other forms of cancer," the release continued.

Crumb rubber fills a need in drought prone places like California, or in busy cities where demand for playing fields is so high that natural grass is not given time to regrow after use. In Los Angeles, for example, even without a drought it is difficult to maintain natural grass fields on city parks because athletes can be found playing so many hours of the day, say parks personnel.

Shredding the rubber into countless tiny particles makes it easier for toxins to enter the body, or leach into the air or water, experts say. Heat and sunlight, two elements in long supply in Southern California, also help break down the rubber and release particles. One industry estimate holds that 4,500 crumb rubber fields exist in the U.S.

Concern over crumb rubber has been building for years, but a recent NBC report has reinvigorated the debate. That report features a soccer coach at the University of Washington, Amy Griffin, who has tabulated a list of more than two dozen soccer players who have cancer. Griffin believes crumb rubber is the cause. Twenty two out of 27 players on her list are goalkeepers -- no coincidence, Griffin says, because goalies often dive to the turf and spend more time rolling on the field than other players.

The federal Environmental Protection Agency has studied crumb rubber and identified a litany of toxins it may contain. But it has left it to states and local governments to choose their own policies.

Several states and organizations have studied the health hazards of crumb rubber, too. By and large they have concluded that the rubber contains relatively low levels of toxins but assert that more research should be conducted.

Crumb rubber makers shred tires of numerous types from numerous manufacturers. Since ingredients vary among tires, it's difficult to determine what exactly each field contains.

Some cities and school districts feel they already know enough to act -- they don't want to wait for California or anyone else to release a study. New York City has banned crumb rubber, and the Los Angeles Unified School District has placed a ban on installing new crumb rubber, though it does have crumb rubber athletic fields. In October, the city of Santa Monica opted to replace an aging crumb rubber field with an alternative material it deemed safer. The field will be replaced this year, the city told KCET.

LAUSD's ban came on the heels of a discovery of lead around 2008 in crumb rubber play areas at nine preschools. Though the lead was "below levels considered dangerous to children," according to press release issued at the time, the district removed crumb rubber from 54 preschools. It later filed lawsuits against a series of turf companies it alleged wrongly sold it crumb rubber containing lead and carbon black. The lawsuits were settled.

California has already studied crumb rubber once. A 2010 study by the state looked at the hazards of inhaling the air above crumb rubber fields. After the study, the legislature was given a report saying that "these fields do not pose a serious public health concern."

That study, Hill said, "didn't do as much as we'd like." His bill calls for a study that would examine crumb rubber for a long list of toxins, evaluate the risk to various populations at varying exposure levels, look for a litany of cancer types connected to exposure, examine the products of various manufacturers, and look at how age of a field, heat or sunlight affect exposure.

For Hill, it's safer to be cautious when it come to children and cancer. "The only responsible thing for us to do is pause for a little and make sure."