Monday, October 13, 2014
October is Breast Cancer Awareness Month. It’s a time to reflect not only on ways to battle, cure and survive breast cancer, but all types of cancer. Therefore, when NBC News did an investigative report on the possible carcinogenic effects of the black filler pellets (called crumb rubber) used in artificial turf fields, it highlighted the paucity of study on the subject. Despite amazing advancements in the detection and treatment of cancers, we actually know far too little about the direct causes. Scientists understand that it’s a complicated formula involving genetics, environmental factors, age, gender, diet, exercise, length of exposure to possible cancer agents, and lifestyle. Isolating which factors are most significant for any given cancer can prove not only daunting but confusing. Since prevention will depend on discovering the antecedents of a particular cancer, the medical community searches for answers. Right now we are better informed on treatments, which have come a long way, and some promising flags for early detection for such cancers as breast, colon, skin and blood. But we still don’t know how to actually prevent cancers from happening.
In NBC’s report, it looked at the possible link between crumb rubber pellets made from shredded tires and blood related cancers, in particular non-Hodgkin lymphoma. The original concern came from Amy Griffin, the associate head women’s soccer coach at the University of Washington. She was never aware of any players with lymphoma, but suddenly 10 years ago several soccer players she knew, and in particular goalkeepers, were diagnosed with non-Hodgkin lymphoma (NHL). It was brought to light vividly when she accompanied one player to her chemotherapy and the nurse said, “Don’t tell me you guys are goalkeepers. You’re the fourth goalkeeper I’ve hooked up this week.” From that point forward, Griffin began to collect data on any youth players with cancer that she was aware of. Her list now stands at 38 players, 34 of whom are goalkeepers. As the mother of a goalkeeper, that fact naturally piqued my interest.
Before we throw the field out with the pellets, it’s important to know that scientists are divided on how harmful the crumbs are and if there is actually any discernable link between them and cancer in youth players. Since the formula for creating rubber tires varies from manufacturer to manufacturer, collecting data is difficult when dozens of brands mix together in the pellets. There are known carcinogens in tires such as arsenic, lead, benzene and polycyclic aromatic hydrocarbons, but authorities argue that with the vulcanization of the tires the chemicals become inert. Even the EPA has said that their studies show no harmful effects from the pellets. Yet under direct sunlight, the rubber can be 10 to 20 degrees hotter releasing gases which lead to a concern of breathing in harmful vapors. Add that red flag to getting the pellets rubbed into open cuts and abrasions and ingesting them unintentionally, and you make the case for further scientific investigation.
I began my professional life as a scientist, so I know firsthand the seriousness and difficulty of creating reliable studies. It’s hard to isolate a factor in an environment where so many factors meet. What is the genetic history of these players? Are athletes just more prone to blood diseases given the way exercise oxygenates the blood? Which, if any, of the chemicals in recycled tires could be linked to the development of cancer? Why are goalkeepers more susceptible than field players? What about football players who spend huge portions of a game lying face down on the turf? What other conditions do these players share, for example, drinking from the same type of plastic water bottle or wearing the same keeper gloves or living close to a freeway? What length and level of exposure might lead to cancer – just once or twice or long-term intense? Then these results need to be replicated in studies by other groups to be verified as true and reliable. Finally, the results must be compared to the general population. Is there a significant difference between soccer players getting NHL and other young people getting it? These are just a few of the difficulties in ascertaining a connection between crumb rubber and cancer.
Right now there are over 11,000 turf fields in America, most of which use crumb rubber. In addition, many playgrounds employ crumb rubber around swings and slides to cushion falls. Even environmentalists are reluctant to give up on the pellets because they are seen as a win-win solution. Landfills are no longer clogged with tires that can’t biodegrade and millions of kids experience fewer injuries on playing surfaces. There are alternatives fillers such as coconut fiber and cork, but these are products which are more expensive and scarce. Nevertheless, New York City no longer builds turf fields in its parks and Los Angeles is approaching a similar ban. The issue becomes does the injury buffering of crumb rubber outweigh the possible cancers? All this concern may actually be moot, as several organizations and studies suggest. A 2006 analysis in Norway concluded that inhalation would not cause “acute harmful effects” and that oral exposure would not increase health risks. Still, the study also suggested that more investigation was appropriate. Short-term studies aren’t nearly as strong as long-term studies, which can explore effects on the developing neurological and physical conditions of young players. Unfortunately by the time such studies are complete most youth players today will be married with kids of their own.
According to St. Jude’s Hospital, nine kids out of a million under age 15 develop NHL each year. There are 81 million kids under 18 in the United States, so that translates to approximately 730 new cases per year. That’s a really small percentage. Of course if your child develops the disease, it’s 100 percent, which is why anecdotal evidence is so powerfully alarming. National five-year survival rates are over 66 percent and increasing every year. To put this all in perspective, 650 children 12 and under were killed in car accidents in 2011, and we still drive to those soccer games on turf fields. All the same we should push for more study. It’s important to discover what correlations might exist between crumb rubber and cancer, not only so we can prevent particular cancers, but so we can also develop ideas on how to unlock other cancer-environmental connections. The names Amy Griffin is collecting make an interesting and significant data base to begin the investigation. Scientists need to broaden that list with names from football (boys are three times more likely to develop NHL than girls), track and other turf field sports. They need to collect data on familial histories, diet, lifestyles and other factors. They will need to compare with the general population to see if there are statistically significant differences. All in all, it will be a long process, but any inquiry will definitely promote research’s goal of early detection and prevention of all cancers.
Childhood cancer strikes terror in any parent’s heart, so hearing a national news organization report that soccer players may be at greater risk due to their playing surface can give us pause. However, given all the data, we need to avoid an alarmist approach. While a risk may exist, consider these facts. The number of general sports injuries far outpace any NHL cases. So taking the overall incidence of sports harm to youth players, NHL has a small, albeit emotional, impact. As a parent, and a parent of a goalkeeper at that, I wouldn’t hesitate to have my kids, grandkids, neighbors, and friends play on a turf field, but I would also ask for more research, while calmly paying attention to possible warning signs of trends or symptoms. Since any cancer can appear in any child at any time, it’s not a bad idea to look out for signs of fatigue, easy bruising, swollen lymph nodes, coughing or trouble breathing, fever, night sweats, and/or weight loss. While these symptoms can indicate cancer, they can also indicate any other number of serious health issues, so following up with a physician would never be a bad idea. Childhood has lots of intrinsic dangers, and as parents we need to measure how much we will restrict our kids’ activities based on risks. In this case, I would recommend “Play on!”