Grass versus turf fields: Researching injuries, threat of cancer
Are turf or grass fields better for athletes to play on? Emma Straw was determined to find out.
Artificial turf first entered the playing field in 1966, when it was installed at the Astrodome, home of Major League Baseball’s Houston Astros. Dubbed AstroTurf, the synthetic grass innovation was praised for its durability and low cost, only to face later criticism as injuries began to arise.
According to the Hospital for Special Surgery, early injuries included anterior cruciate ligament (ACL) tears, concussions and ankle sprains. As more studies followed, incidents of turf burns and turf toe, a stiff big toe caused by arthritis, appeared.
In response to the growing injuries, artificial turf companies began working on improving their product to replicate the look, feel and safety of natural grass.
As of 2017, according to the Synthetic Turf Council, a trade association representing the synthetic turf industry, more than 12,000 synthetic turf sports fields are in use throughout the United States.
Made of nylon, polyethylene and tire crumbs, turf fields are cheaper to maintain than natural grass, can withstand heavier, more frequent use, conserve water and eliminate the use of potentially harmful pesticides and fertilizers.
However, costs are steep. Depending on the type and company, artificial turf fields can cost upwards of $750,000 and even more in medical bills.
According to Justin Shaginaw, an athletic trainer for the U.S. Soccer Federation, a study published in 2011 showed that there was a higher incidence of ankle injuries on artificial turf among football, rugby and soccer players.
The reason: As the coefficient of friction increases, there is an increase in the rate of lower extremity injuries.
As more concerns were raised and studies were conducted, results from a 2013 study that looked at injury rates among female soccer players showed a higher injury incidence rate on grass than on turf.
Shaginaw concluded that there is no definitive answer regarding injury rates and artificial turf, but that the key to injury prevention is wearing the proper cleats, those made specifically for natural grass or turf.
Other studies show that the effect of artificial turf on injury rates is still controversial. According to Dr. Mark Drakos, an orthopedic surgeon and sports medicine fellow from the Hospital for Special Surgery, most scientists believe that there are two material properties that can affect injury rates on turf and grass: the coefficient of friction and the coefficient of restitution.
While friction refers to the resistance that one surface or object encounters when moving over another, restitution is defined as the ability of a surface to absorb shock.
Fields with low shock absorbency place more impact upon an athlete during a collision and can result in higher injury and concussion rates.
While physical injuries dominated the early grass versus turf debate, new concerns about crumb rubber in artificial turf fields and their connection to cancer have since taken over.
In 2009, former U.S. women’s national team goalkeeper and current University of Washington Assistant Head Coach, Amy Griffin, compiled a list and collected data about athletes with cancer who have played on crumb-rubber artificial turf. Griffin suspected that the crumb-rubber, or tire crumbs, contained carcinogenic chemicals.
The Washington State Department of Health and researchers at the University of Washington School of Public Health conducted an investigation into whether the cancer rate seen in Griffin’s list was “unusual” and concluded it was not.
In addition, the Connecticut Department of Public Health conducted research in 2011 on five in-state crumb-rubber fields and found that health risks were not increased by the rubber vapors and particulates.
While research has not found significant links between cancer and crumb-rubber from turf fields, research is still ongoing.