Saturday, June 20, 2009

By William S. Bike

Gazette Magazine, Chicago

Plans to possibly cover the field at the Chicago's Sheridan Park with artificial turf have raised concerns with a national expert on turf-related problems from the University of Illinois at Chicago (UIC) School of Public Health, and counter-arguments from an artificial turf company spokesman.

"Right now, we are deciding whether the community prefers grass or artificial turf," said Larry Doody of the Sheridan Park Advisory Council.

A UIC expert is not a fan of artificial turf, however.

"We are worried about harmful chemicals," said Susan Buchanan, MD, MPH, associate director of the Great Lakes Center for Children's Environmental Health at the UIC School of Public Health. "Those can be heavy metals including lead, although most of the newer fields are made with lead-free materials, or they can be plasticizers like phthalates and polyaromatic hydrocarbons.

"Some of these chemicals are carcinogens. Some cause other chronic health effects when inhaled or ingested," she continued.

FieldTurf from Tarkett Sports is a brand being considered for Sheridan Park. It is made of a polyethylene/polypropylene fiber blend, silica sand, and ground styrene-butadiene rubber (SBR) infill. Darren Gill, director of marketing at Tarkett Sports said, "FieldTurf currently provides lead-free products. This statement can be confirmed via test results from independent laboratories. The safely of the FieldTurf product continues to be reaffirmed as FieldTurf's fibers have been proven to pose no harm to humans."

Gill said, "The plastic turf blades have the same makeup as shopping bags being used in your local grocery store. Everyone knows that SBR is in car tires, but it's actually used in foam mattresses, chewing gum, cosmetic sponges that women use, adhesive bandages, cleaning gloves used in the kitchen, water hoses, sports balls, and flip flops. People that are opposing rubber in the turf are actually using the same products daily. Silica sand is found in every beach."

Arguments over heat

Buchanan noted that artificial turf fields "act as heat sinks," she said. "They absorb heat, so very high temperatures have been measured on field surfaces during sunny weather."

Milone & MacBroom, a Connecticut engineering, landscape architecture, and environmental science firm, said in a study of thermal effects associated with artificial turf, "Maximum temperatures of approximately 156 degrees F" for the fibers "were noted when the fields were exposed to direct sunlight for a prolong period of time," and a maximum of 101 degrees for the rubber infill. They recommended wetting the turf, which provides "significant cooling."

Gill said, however, that the study also examined the heat levels two and five feet above both artificial turf and natural grass, the head and upper-torso levels of youngsters and adults. "and that's where they showed the difference in heat between the two is actually very marginal. The major concern here is heatstroke. When you look at heatstroke it's not much of a difference."

The study of the air above the field, Gill said, showed that "after three hours, the air above the natural grass surface was hotter than above artificial turf, and after seven hours the air above turf was 102 degrees and above the grass 99 degrees. Actually, the peak temperature was reached above the natural grass—just under 104 degrees."

Although modern synthetic turf fields are softer than older ones which on which turf was placed over hard surfaces, Buchanan said there still is "a concern about increased musculoskeletal injuries like more ankle and knee sprains."

"There's also a concern about more skin abrasions, which may result in more secondary skin infections," she continued.

Injury factor

A study by Michael C. Meyers, PhD, of West Texas A&M University, and Bill S. Barnhill, MD, Panhandle Sports Medicine Associates of Texas, showed that athletes get injured on artificial and natural turf in different ways. They said there are more non-contact injuries, epidermal (skin) problems, muscle-related trauma, and injuries during higher temperatures on artificial turf, and more head and neural trauma, ligament injuries, and injuries taking longer to heal sustained on natural grass.

Tarkett literature describes turf fibers as "quite soft, which will virtually eliminate skin abrasions."

Synthetic turf infill often is made from recycled rubber tire material called "rubber tire crumb."

"There are a lot of anecdotes that this tire crumb gets on the skin and sticks to it, so children who come home after having played on these fields take it into the homes and get it on other family members as well," Buchanan said.

"FieldTurf's crumb rubber infill is comprised of the cleanest cryogenic rubber available on the market today," according to Gill. "The products meet any state standards as it relates to VOC's and PAH's."

VOC stand for "volatile organic compounds" and PAH stands for "polycyclic aromatic hydrocarbons."

Gill cited a State of New York Department of Health fact sheet on the subject, which noted that "information on crumb rubber and crumb rubber infilled turf fields indicates that ingestion, dermal, or inhalation exposures to chemicals in or released from crumb rubber do not pose a significant public health concern."

"I support more recreational space for urban communities absolutely, and I realize that grass fields require maintenance," Buchanan said. "Sometimes pesticides are used on grass fields; that concerns me as well, although the pesticides usually dissipate very quickly and become inactivated in the sunlight. But I need more reassurance via scientific exposure data that people who use these fields frequently, like children on organized sports teams who are being exposed regularly, that their health is not at risk.

"I support the Chicago Park District creating or upgrading more play space for children, but my role as a health professional is to look out for the health of the people, especially children who are more vulnerable to exposures," Buchanan said.

Gill cited "hundreds of studies" on the safety of synthetic turf.

Buchanan said, "There are studies that have looked at the components of rubber tire and there are several health risk assessments—a mathematical model to predict health risks. What hasn't been done are actual exposure measurements while people are playing on the fields," she concluded.

Community activism

In several areas of the country, locals are increasing their opposition to synthetic turf.

In New York City in February, a coalition of environmental and civic groups called for a moratorium on the addition of artificial turf to sports fields while the New York City Health Department conducts a review of health risks. The coalition includes a former New York Parks commissioner, New Yorkers for Parks, and New York Lawyers for the Public Interest. A bill was introduced in the New York City Council to prohibit the use of certain synthetic turfs by council member Maria Baez.

Bills were proposed in California, Connecticut, Minnesota, New Jersey, and New York last year that would prohibit installing artificial turf fields.

A community group in San Carlos, CA, "Save San Carlos Parks," on May 13 sued that city for approving an artificial turf playing field.

Gill sees the opposition as uninformed or having ulterior motives.

"You have groups who hear that there's something negative associated with turf, and without doing any homework or any research they form an opinion," Gill said. "They're entitled to it, but I think the science is more important than anything. I think the science is there to back up the safety.

"Some groups oppose the idea of spending a lot of money on turf, but the only argument they can use to stop the process from moving forward is talking about, 'it's unsafe for our kids,'" Gill noted. "I usually see the two tied together. A group doesn't want to see the money spent so they argue the turf is unsafe. I think that there's an ulterior motive behind talking about the safety."

According to Save San Carlos Parks and a Maryland group, Parents Coalition of Montgomery County, the Synthetic Turf Council, which has a representative of FieldTurfTarkett on its board, successfully lobbied the federal Consumer Product Safety Commission in May 2008 to make sure that artificial turf would not be classified by the CPSC as a "children's product," as that would require more stringent testing for lead.

Gill countered, "I wish we could state that we had enough power to have that effect on the CPSB. The CPSB made that determination on their own.

"It really comes down to the overall classification of how the product is being used," he continued. "I don't believe artificial turf is a children's product per se. I look at turf more as a flooring or carpeting product. I don't have any problem worrying about if FieldTurf is going to pass any testing with flying colors.

"If natural grass were classified as a children's product, it would be banned. Natural grass contains more harmful elements than any children's toy could ever contain, probably 100 times more bacteria than artificial turf," Gill concluded.