In the 1960s, my high school (I’m giving away my age) had what is probably best described as a pathetic football field. Patchy grass that was almost as much sand as it was grass; decrepit bleachers that had room for a couple hundred people; and a small but enthusiastic crowd for game nights. My high school no longer exists, but the school that has taken its place has what I would call a stadium. Built into a natural valley, the football field is surrounded by seating worthy of a professional sports team with room for thousands. The field itself is not grass, but artificial turf, sometimes called astroturf.
My high school is not alone. Synthetic turf is wildly popular. One industry insider says that there were 140 million square feet of synthetic turf installed in the US in 2011, and 2012 is probably no less. It’s not just schools: parks, sports centers, even child care centers are installing synthetic turf.
When using a synthetic turf field and looking out over that expanse of plastic, it’s almost impossible not to wonder about the chemicals you and your children may be exposed to as you (or the kids) execute your famous slide tackle, pick up a ball that’s been rolling across the turf, breathe hard at the end of a sprint, or grab some water during a time out.
One chemical in artificial turf gained a lot of notoriety about five years ago: lead. At the time, the turf industry typically used lead-containing pigments to keep the synthetic blades bright green. Fortunately, through a collaboration with the California attorney general, CEH was able to get major turf companies to switch to safer, non-lead based pigments. Since older turf fields with lead pigments may still be a problem, CEH has created a map showing hundreds of California turf fields we have tested for lead.
But what other chemicals may be lurking in that plastic? It’s a complicated story. In addition to the plastic blades, many modern synthetic turf sports fields use a synthetic “dirt” that provides a base for the plastic blades and cushioning for the athletes who use the field (the fake dirt is less common in turf used for landscaping or golf installations). The technical term for this synthetic dirt is “infill” and a common material for infill is recycled, ground, automobile tires. Recycled tires are also used to make synthetic mulch and pavers for playgrounds.
Tires, especially used tires, are a complicated mix of chemicals. State health scientists in California have done three reports (2007, 2009 and 2010) about potentially toxic chemicals in infill. The state scientists identified a whopping 33 chemicals in tire-based infill that have serious health concerns like cancer and reproductive harm. This is probably just a beginning. The California scientists also summarize a study that found 112 chemicals off-gassing from synthetic turf and a study that found 155 chemicals. Most of these were unidentified.
So what are we to make of this chemical soup? The data about these chemicals are sparse, and many of them are found in lots of places besides in synthetic turf. Well-known pediatrician and public health expert Dr. Phil Landrigan of New York’s Mt. Sinai School of Medicine says:
“What is not yet known is the extent to which these chemicals may get in to the bodies of children playing on turf fields… or the extent to which they may leach from the fields into the surrounding environment, soil and groundwater.”
Dr. Landrigan makes some simple suggestions to reduce exposure of children and athletes to infill chemicals: remove the infill pellets from shoes and clothes after the game/practice is over; shake out equipment and clothes (but not in your car or your house); and wash and shower thoroughly after playing. We’d also suggest washing hands before snacking, drinking, or adjusting mouthguards.
Infill made from materials other than recycled tires is available (like this coconut shell and cork-based product), but full information about the ingredients in products can be hard to find. If your town or school is installing a new field, be sure that it considers all of the alternatives – including natural grass–that are available.