A state Department of Health analysis of cancer rates among soccer players in Washington state found lower than expected rates, according to a report released Wednesday.
The study was prompted by an ongoing debate over whether the use of crumb rubber — made from recycled tires — to cushion artificial turf fields could cause cancer in young athletes. That controversy has been the subject of multiple news reports, including from NBC, ESPN and, last year, The News Tribune.
The state findings were met with criticism from concerned families of cancer-stricken athletes and others who had pushed for the study.
Dr. Cathy Wasserman, an epidemiologist with the Washington State Health Department, called the statistical analysis a “first step.”
“We are recommending that people who enjoy soccer continue to play, regardless of the type of field surface,” she said.
But she added that the recommendation is “based on what we know today.”
“Our investigation was not designed to discover the causes of cancer,” she said. Nor was it designed to explore crumb rubber exposure as a cause, she added.
Instead, its purpose was to look at whether cancer occurred at a higher rate among soccer players than among all Washington residents in the same age group. The study team, which included researchers from the University of Washington School of Public Health, concluded that it did not.
Lauren Jenks, director of the health department’s office of environmental public health sciences, said the report showed that “we are seeing less cancer among soccer players than we would expect if soccer players got cancer at the same rate as everybody else.”
Wasserman said research conducted elsewhere has not suggested that crumb rubber on athletic fields presents a significant health risk. The synthetic turf industry has repeatedly said there is no proven link between its product and cancer.
But Wasserman noted ongoing studies by the federal government and the state of California that could provide more information.
“Assurances of the safety of artificial turf with crumb rubber is limited by the lack of adequate information on potential toxicity,” she said. “We are acknowledging gaps in our knowledge. But we have to make recommendations based on the state of knowledge today.”
Officials said they would continue to monitor ongoing research by others.
The state study was prompted by reports of cancer diagnoses among players that had been collected by University of Washington women’s soccer coach Amy Griffin.
Wasserman said the department shared results of its investigation with Griffin and concerned families Tuesday. Griffin said Wednesday that she appreciates the state’s efforts, but deemed the report “inconclusive.”
“This wasn’t a study on turf fields, not did it address any of the potential carcinogens or toxins,” Griffin said. “You need to dig deeper.”
Among the families represented at Tuesday’s meeting with health officials: the Beardemphls of Tacoma. Mike and Stephanie Beardemphl’s son Luke, a goal keeper at Stadium High School who also played on other teams, died in 2015 at age 24, after a seven-year battle with Hodgkin lymphoma.
The Beardemphls said Wednesday that the state analysis left them with unanswered questions.
“The numbers they gave us didn’t make sense,” said Stephanie Beardemphl, who was at Tuesday’s meeting. She said some parents appeared angry, but most were disappointed.
Mike Beardemphl said the report failed to address families’ concerns. He said he would have liked to see more study of whether goal keepers are more affected, because their position demands more ground contact than other players — and potentially more crumb rubber exposure.
Stephanie Beardemphl said it should have looked more closely at higher-intensity players like her son.
“He was daily out there on the turf — diving in it, not just standing on it,” she recalled.
Griffin echoed that opinion.
“One of my biggest concerns has always been with the elite goalkeepers — the keepers that train in the stuff for multiple hours every week, 12 months out of the year,” she said. “This is the group that has, by far, the most exposure.”
Griffin began gathering information in 2009 after learning about what seemed like an unusual number of soccer goalkeepers who had been diagnosed with lymphoma.
Griffin and others theorized that soccer players, particularly goalkeepers, could have become ill because of their exposure to crumb rubber. Griffin’s information-gathering sparked a nationwide debate over the safety of crumb rubber-cushioned artificial turf used on school and park fields. The materials became popular during the 1990s.
After Griffin went public with her concerns, she began hearing from athletes and their families around the country. She started keeping a list. By 2016, the list included more than 200 athletes, including more than 50 from Washington state.
The state study released Wednesday compared the number of cancers among soccer players on Griffin’s list to the number that would be expected if the cancer rates among soccer players were the same as those for all Washington residents of similar age.
The study focused on those between the ages of 6 and 24 who were diagnosed between 2002 and 2015.
The state report found 28 cases from Griffin’s list met that criteria, but said that — based on its statistical predictions — 1,384 cases would be expected if soccer players experienced cancer at the same rate as Washington residents of similar ages.
The report also looked at information from Griffin’s report on specific cancers and certain types of soccer players.
Researchers also gathered answers to detailed questionnaires from 35 of the people on Griffin’s list.
Observed and expected cancers
The state Department of Health used statistical analysis to look at cancer diagnoses among soccer players. The report looked at data on players with cancer gathered by a University of Washington soccer coach and compared it to a calculated expected number of cancer diagnoses. The report compared cases from the coach’s report of those between the ages of 6 and 24, who were diagnosed from 2002 to 2015, with what would be expected if soccer players experienced cancer at the same rate as Washington residents of similar ages. A ratio greater than 1 would indicate that the number of cancer diagnoses reported by the coach was higher than expected.
All soccer players
All types of cancer
SOURCE: Washington State Department of Health
Read the report: doh.wa.gov/Portals/1/Documents/Pubs/210-091.pdf.
Advice for athletes
The state Department of Health says currently available research does not indicate a significant health risk from synthetic turf fields. But it does offer advice for athletes and families concerned about potential health effects:
▪ Wash hands after playing on the field and before eating.
▪ Take off shoes or cleats, sports equipment and soiled uniforms outside or in the garage to prevent tracking crumb rubber into the house.
▪ Shower after play, and quickly clean any cuts or scrapes to help prevent infection.
▪ Athletes who accidentally get crumb rubber in their mouths should spit it out; don’t swallow it.