Artificial turf with "tire crumb" – present in the University of Montana football stadium and softball field – contains 96 chemicals including 12 known carcinogens, according to a recent analysis by Yale University.

From afar, the football field in Washington-Grizzly Stadium looks like green grass with white stripes. Up close, run a foot across the surface, and countless tiny black pellets pop up, all part of the 40,000 ground-up tires in every field, according to Environment and Human Health Inc.

Environment and Human Health is a Connecticut nonprofit dedicated to protecting human health from environmental harms. The group published results of the preliminary study on its website, the precursor to a full report.

Board president Nancy Alderman said Wednesday the nonprofit has been researching the harms of artificial turf since 2006. At the time, the group lobbied for a moratorium on installing the turf in Connecticut, but she said the health department declined to issue one.

However, the rubber surface is ubiquitous in fields and present as mulch in playgrounds across the country, and the analysis adds to a growing body of evidence the material is harmful to human health, Alderman said. She also said the government has not tested half the chemicals detected in the turf, so additional health hazards are possible.

"This is one of the largest failings of government that we have ever seen. Ever," Alderman said Wednesday.

The city of Missoula does not use the tire crumb surface in its playgrounds, according to a Parks and Recreation official.

At least one company selling the turf vouches for it, pointing to the conclusions of a toxicologist. Darren Gill, vice president of marketing for FieldTurf, a manufacturer of artificial turf, said plenty of available science speaks to the safety of crumb rubber.

"The 'Yale study' is the furthest thing from a study," Gill wrote in an email.

At UM, athletics spokespeople said the material is light years ahead of grass when it comes to other serious injuries and maintenance.

Athletic director Kent Haslam said he isn't familiar with the most recent analysis, but he said the country is going the way of artificial turf. He also said he counts on the companies selling the athletic surface to ensure it's not harmful.

"When we buy a product, we rely that the product is tested and is safe," Haslam said.


The report described Yale's process.

"There were five samples of infill from five different installers of fields and nine different samples of rubber mulch taken from nine different unopened bags of playground mulch," it said.

The result was "a witch's brew of toxic substances," according to Yale Alumni Magazine, which quoted lead researcher Gaboury Benoit, a professor of environmental chemistry and engineering.

Data collected from soccer players supports the findings the artificial turf is harmful, Alderman said. Soccer players who have played on the turf for a number of years are getting cancer, she said, namely lymphoma and leukemia.

"The reason that is important to know is both those cancers are affected by environmental exposure," she said.

The majority of the players getting the cancers are goalies, who are diving and more heavily exposed, according to the Environment and Human Health's website.

"They are close to the ground. They are the canaries in the coal mine," Alderman said.

Online, the nonprofit refers to data being compiled by Amy Griffin, a soccer coach based at the University of Washington. Griffin "has been keeping a list of athletes who have developed cancer after playing on turf fields containing waste tires."

"So far, she has identified 126 athletes, 109 of which are soccer players, 10 were football players, and six were field hockey and lacrosse players, who have developed different forms of cancer," read the February 2015 post.

It noted the following as reported cancers, excluding rare forms:

  • 51 lymphomas.
  • 19 leukemias.
  • 10 brain.
  • 9 testicular.
  • 9 sarcoma.
  • 6 thyroid.

"It is important to note the predominance of lymphomas and leukemias," the story said. "1,3-butadiene is connected to lymphoma and benzene is connected to leukemia. Both of these chemicals are present in rubber tires."


Various UM teams use the artificial turfs, including softball players in the newer field, and sometimes soccer players in the stadium.

Tyrone Holmes plays football for the Grizzlies, and as a defensive end, he often ends up down in the turf. He said he is not concerned about the health hazards and would not be without substantially more research.

Holmes, of Oregon, played on grass in high school, and he said the artificial turf was a significant improvement. The grass gets torn up, and it's uneven and soft. 

"I like playing on turf a ton more than grass. I feel faster on turf than I do on grass. It has less give," Holmes said.

Chuck Maes, assistant athletic director of internal affairs, said a frozen field of grass poses dangers to players as well. In the past, he said, athletes were landing on an icy field, like falling in a parking lot, or hitting a head on cement.

"It was very unplayable and unsafe," Maes said.

He saw many players hurt their knees and ankles. Concussions are down in recent years, he said, although he attributes the decline to a variety of factors.

At least in Montana, he said, the seasonal weather means grass doesn't work well, for the safety of players or for maintenance. The artificial turf, on the other hand, supports the teams.

"It has given us a nice, uniform playing surface where the field is never determining the outcome of the game for us. It's the players on the field," Maes said.

The stadium went from grass – and sometimes a mud pit – to turf in 2000, Haslam said. The areas of maintenance UM no longer needs to worry about include mud, water, fertilizer, paint and mowing.

The turf in the softball field is some six months new, but the one in the stadium will be up for replacement in a couple of years, Maes said. As planned, he anticipates UM will install artificial turf.


Gill, of FieldTurf, a Tarkett Sports Company, pointed to a report from toxicologist Laura Green as a refutation of the Yale analysis.

In the report, Green said she was asked by Rubberecycle to comment on the assessment of the risk of cancer posed by the rubber material, in this case, mulch in playgrounds. Rubberecycle manufactures rubber mulch.

"I have examined the relevant evidence, and have found that rubber mulch is neither known nor reasonably expected to cause cancer, and is otherwise safe for use in playgrounds," Green wrote in a memo.

Green is identified as consulting toxicologist in the report. Based in Massachusetts, she could not be reached late Wednesday about whether the product manufacturer paid for the study.

Green is founder and senior toxicologist of Cambridge Environmental as well as a diplomat of the American Board of Toxicology. She is also an author of the text "In Search of Safety: Chemicals and Cancer Risk."

In the memo, Green said that despite news reports based on Griffin's data, she had not seen any peer-reviewed studies or findings in scientific journals.

"To my knowledge, no systematic or scientific study of these cases has been performed or published," she wrote.

She also said the information the coach is collecting is incomplete as well as unverified, so scientists can't draw noteworthy conclusions from it. Plus, she said, even if the pattern exists, the cause could be totally unrelated.

"(And) we do not even know if the reports are completely accurate," Green said.


Betsy Story, vice president of the Associated Students of the University of Montana, said the student government wants students on campus to be satisfied with all aspects of campus life. If students have concerns about the turf, ASUM should hear about it, she said.

"We're always a resource to students who feel if something is significantly unjust, or in this case harmful to their bodies and possibly cancerous, they can come to ASUM and we can bring it up," Story said.

As the public considers the matter, though, Alderman said it is important to get scientific information from the scientists. She said the coaches who promote the turf are ill-equipped to assess the dangers because they are trained in athletics, not in public health.

"The scientists who are trying to educate the public that these fields are dangerous are being drowned out by industry and by the coaches around the country," Alderman said.

The city of Missoula does not use "tire crumb" in playgrounds, according to Donna Gaukler, director of Parks and Recreation. It uses only wood fiber or a rubber product that is "poured in place."

"We have an artificial turf going into a field at FMRP (Fort Missoula Regional Park), but we have not selected the final product yet," Gaukler wrote in an email.