SACRAMENTO – Following increasing concerns about the safety of recycled tire material used on synthetic turf fields, the Obama administration announced Friday a federal study to look into potential health risks.

The material in question — ground-up waste tires — has been a source of debate across the country since late 2014, when parents and health and environment advocates began demanding studies about whether repeated contact with the material could cause cancer.

That’s the year a University of Washington soccer coach came forward with a list of a few dozen young athletes with cancer who regularly played on turf fields — surfaces where tire pieces have been spread thickly to provide cushion and traction. The pieces often end up in the mouths, ears and clothing of athletes.

The list of cancer-stricken players now incudes more than 200 athletes across the country who play a variety of sports on turf fields, including football and field hockey. Half of the ill athletes on the list are soccer goalies under age 35 whose position requires them to do a lot of diving into the turf fields.

California has 902 synthetic turf fields, primarily in the Bay Area and Los Angeles County, according to the California Office of Environmental Health Hazard Assessment.

“Parents and athletes of all ages want and deserve conclusive answers on whether exposure to crumb rubber turf can make one sick,” said Sen. Bill Nelson, D-Fla., who urged President Obama in a letter last month to authorize the study. “Combining the resources and expertise of three federal agencies to help find those answers is the right thing to do.”

The three agencies that will carry out the study are the U.S. Environmental Protection Agency, the Consumer Product Safety Commission and the Agency for Toxic Substances and Disease Registry at the Centers for Disease Control and Prevention.

The study will include a technical team of almost 50 federal employees and a research budget of $2 million, said Laura Allen, EPA spokeswoman.

The idea will be to discover what chemicals are in crumb rubber and how people are exposed to them. The agencies expect to release a draft report of findings and conclusions by the end of the year.

“We know people are concerned about artificial turf fields, and players and their families want answers,” Allen said. “Limited studies have not shown an elevated health risk from playing on fields with tire crumb, but the existing studies do not comprehensively evaluate the concerns about health risks from exposure.”

The announcement of an EPA-involved study represents a reversal of sorts for the federal agency.

After conducting a study in 2009 that is often cited by industry groups as validating the safety of crumb rubber, the agency at first found the material posed “low levels of concern.” The EPA later backtracked and said the study was limited in scope, and that no conclusions should be drawn by it.

Amid growing concern over the past year, the EPA said it would not conduct another study and instead said it was up to states to conduct their own research.

The’s EPA’s hands-off approach comes after the agency spent years marketing crumb rubber for sports fields and playgrounds as a means of reducing the nation’s stockpile of waste tires, as first reported in The Chronicle in February 2015.

Then came Friday’s announcement that the EPA would participate in a new study.

“We’re happy it’s getting this level of attention,” said Jeff Ruch, executive director of the Public Employees for Environmental Responsibility, a national nonprofit that has fought the EPA since 2009 over its endorsement of ground tires. “What’s unstated is that this is a market largely created by an EPA program. This is a classic example of leaping before you look. Now, they are belatedly taking a look.”

The Synthetic Turf Council, an industry group, said in a statement Friday that it hoped the new study would “settle this matter once and for all.”

“We have consistently said that we support all additional research,” the group said. “At the same time, we strongly reaffirm that the existing studies clearly show that artificial turf fields and playgrounds with crumb rubber infill are safe and have no link to any health issues.”

The federal study comes as California is preparing its own study.

California officials authorized a $2.9 million study on the health effects of using recycled tire pieces on artificial turf. State Sen. Jerry Hill, D-San Mateo, initially called for the study in legislation that also would have required a moratorium on new fields in California while the state studied health risks. That bill died, but the state moved forward with the study anyway.

This year, Hill returned with a watered-down bill to require only that communities publicly discuss alternatives to crumb rubber.

But even that died after labor unions that spend millions on campaigns and lobbyists poured money into defeating it, saying it would put jobs in jeopardy. Their effort worked as SB47 was killed in committee last month.

“My concern is that the industry has been so strong in fighting any legislation that hopefully with better evidence and better research we can present the facts whatever they may be,” Hill said Friday.

Melanie Marty, deputy director for scientific affairs at the Office of Environmental Health Hazard Assessment, said California will work with federal agencies to ensure similar methods of examination are used so there aren’t conflicting findings.

While the state studies crumb rubber, California will continue to award millions of dollars in subsidies to schools and cities so that they can install public playgrounds and fields using the questionable materials.

University of Washington assistant soccer coach Amy Griffin, whose list of cancer-stricken athletes is credited with sparking renewed calls for research on crumb rubber, said Friday that many people continue to reach out to her with safety concerns.

“In this last year, I’ve learned there are many more questions than answers,” she said.