When the U.S. faces Paraguay at the World Cup on June 12 at SoFi Stadium in Los Angeles, the teams will play on a natural grass surface, which, a month earlier, The top of an underlying artificial-turf field was carefully stitched together. This “hybrid turf” installation was part of a broader effort ahead of the World Cup to ensure that the world’s best football teams played primarily on natural grass surfaces.
FIFA, the governing body of the World Cup, has banned the use of synthetic turf in World Cup games for years, primarily because of a Player’s risk of injury increasedWhich has been well established. Synthetic turf is also notorious for causing poor turf burn, as its material is a poor solar radiator and can reach up to. 200 °F (93 °C).
However, many in the broader sports community are concerned that synthetic turf could cause more lethal harm, such as exposure to dangerous levels of heavy metals, cancer-causing chemicals, and microplastics.
A hybrid turf field was installed at the New York New Jersey Stadium ahead of the World Cup final to be played here in July. FIFA mandated that all World Cup games be played on natural grass surfaces, although chemical risk concerns did not play a large role in that decision.
(Image credit: Charlie Tribleau via Getty Images)
A recent 10-year study in California found no significant risks from the chemicals in artificial turf. But experts don’t agree that the study has calmed concerns about artificial turf. here’s why.
wonder of the space age
In the 1960s, artificial turf was considered another wonder of the space age, reflected in the AstroTurf brand name.
“Vacuums and brooms are the only maintenance items required,” Mentioned in an article After the 1966 Houston Astros–Los Angeles Dodgers game. first generation ground Thick nylon carpet was used on the field, but in the 1970s, it was replaced with “2G” turf, which used a slightly less abrasive polyethylene-fiber carpet surface and a cushioning layer of sand underneath.
The latest iteration, 3G, offers better traction and shock absorption than is typically provided by ground-up used tires that are treated with a variety of additives to strengthen and prevent rubber degradation.
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Rolls of artificial turf. Most turf now uses infill made from ground up car tires. This is at the center of the debate about the safety of infill turf.
(Image credit: Carl-Hendrik Teitel via Getty Images)
This infill is the root of the issue: All those tire pieces contain hundreds of chemicals and “created this risk situation that never existed before,” Rachel Masseyan environmental health researcher at the University of Massachusetts Lowell Center for Sustainable Production told Live Science.
more than 95% of 18,000 to 19,000 turf areas The US now includes tire-crumb infills. Astroturf continues to be a leading company offering 3G products. (Live Science contacted AstroTurf to discuss the company’s products but did not receive a response.)
Harmful chemicals?
Some researchers are concerned that turf contains about 400 chemicals that are linked to various health risks. asthma To leukemia.
“None of these [risk assessment] Studies dispute the fact” that those chemicals are present, Massey said. “So then all the debate is about how much risk there really is.”
To assess whether that exposure reached harmful levels, the California Office of Environmental Health Hazard Assessment (OEHHA), part of the California Environmental Protection Agency, studied the health effects of chemical exposure caused by synthetic turf.
“We identified and evaluated as many chemicals as we could in the crumb rubber by taking non-targeted samples.” amy gilsonOEHHA spokesperson.
They tried to measure exposure Metals are commonly found in Turf infill contains lead, cadmium, manganese, and zinc, with zinc often found at levels above US regulatory guidelines. Although zinc is essential for the body, it can harmful at high levelsWith the potential to cause anemia, damage the pancreas, and reduce fertility.
He also saw carbon black, a strong tire filler material which is shown Kill human cells in lab dishes; Benzene, which has been combined in many ways leukemia; toluene, which is toxic to the nervous system, liver and kidneys; and polycyclic aromatic hydrocarbons, compounds that are most commonly found in tobacco and wood smoke and are Linked to cancer in animal studies.
A recent study out of California looked at the risk levels of a myriad of chemicals found in infill used for artificial turf fields. Much of this infill is made from used car tires.
(Image credit: Maxshot/Getty Images)
Another potential concern came to light last year, when 1,3-Dimethylpropylamine (1,3-DMBA), a stimulant banned by the World Anti-Doping Agency, It was detected in post-match samples The opposing teams were represented by eight Norwegian Women’s Professional League football players. Artificial turf was found to be the source of the banned substance. With tire wear, 6PPD – a substance often added to tires to limit ozone-depleting emissions – can degrade into 1,3-DMBA, which was detected on the field where the game was played.
Its presence was also noted in a California EPA report microplastic In the field.
In 2023, European Union announced ban Effective ban on sales of products containing intentionally added microplastics 2031. Specifically, it named granular infill within artificial turf as the “largest source of microplastics intentionally introduced into the environment.” The US does not have a similar law.
Microplastics can harm human health By accumulating in various parts of the body through ingestion, skin contact or inhalation.
Early research on human cells in laboratory dishes indicates that Microplastics can damage the lining of blood vessels And promotes the formation of atherosclerotic plaques and blood clots. Other studies have proposed possible links between microplastic exposure and asthma And inflammatory bowel disease. However, there is much uncertainty about how microplastic exposure is measured and whether this exposure causes diseases or is simply a proxy for some other factor that causes these conditions.
“Insignificant” long-term harm
The California EPA focused on chemicals in tire infill that could potentially cause harm in high amounts. Then, it estimated the level of risk in players, referees and spectators through direct contact, inhalation or unknowingly swallowing tire pieces. First, they estimated risk indirectly by observing people.
“We actually had teams of people going out and taking video of players on the field,” Gilson said.
The research team also collected samples of artificial turf and then placed them in laboratory dishes with synthetic bodily fluids such as sweat, saliva and small intestinal fluids and then measured the concentrations of dozens of potentially harmful chemicals within those fluids. To be more conservative, they assumed that each chemical detected in their experiments would be completely taken up by human cells, jocelyn clouda toxicologist at OEHHA, who worked on the study, told Live Science.
The study found “no acute risk,” meaning short-term exposure to the substance is unlikely to cause immediate harm, he said, and the risks of long-term health effects such as cancer or reproductive harm were “negligible.”
But some experts said the study methodology was flawed. Andrew WattersonAn emeritus professor of public health at the University of Stirling in the UK said the study should have taken urine or exhaled air samples directly from real people exposed to artificial turf, rather than estimating exposure to synthetic body fluids.
Wrong approach to risk assessment
The bigger problem, says Massey and several environmental researchers Live Science spoke to, is that the underlying approach used by the California study — and most other environmental assessments conducted in the US — is flawed.
Rather than asking whether an average person is at risk, society should aim to reduce risk across the entire population, which also protects those at higher risk. Instead of asking, “Is this risk acceptable?” The latter approach asks, “How can we create the healthiest, safest playing surface for a child?” Macy said.
The California report included referees and spectators in addition to players, but does not include other at-risk groups, such as people exposed to chemicals leached into water supplies from synthetic turf, said Tracy Stewart, a Medway, Massachusetts resident who advocates against the use of artificial turf.
Another byproduct of 6PPD, a chemical associated with doping, has been It has been shown to cause mass die-offs of coho salmon. So when scientists started finding dead salmon near an artificial turf field in Vancouver 6PPD-Q and a range of other chemicals detected With stormwater runoff, the community was concerned.
The California study estimated 6PPD-Q exposure levels in synthetic bodily fluids, but did not model how groundwater would be affected. And without well-established safe limits for this chemical, the California study couldn’t assess its risk.
Beyond 3G area
The attraction of synthetic turf is all about “increased hours of use” garnet brownbillSpokesperson for the Natural Turf Alliance, a non-profit organization that advocates alternatives to synthetic turf across Australia. “It’s not affected by the weather, it never shuts down, and people claim it’s maintenance-free — it’s not,” he told Live Science.
However, in response to the European Union’s ban on microplastics in infill, many scientists are working on alternatives that may provide similar benefits.
Turf being installed at New York New Jersey Stadium. Such hybrid turf is composed of 99.5% grass and 0.5% stitching material.
(Image credit: Charlie Tribleau via Getty Images)
One material in development is hybrid turf, whose surface is “99.5% natural grass” with an additional 0.5% stitching material made of either plastic or biodegradable polymers, said Aaron Golembiewski, head of business development at TurfTalents, a company that consulted for FIFA on the installation of hybrid turf in several U.S. stadiums. “Hybrid turf is stronger than grass alone,” Golembiewski told Live Science. “It grows [the] “The amount of play.”
It is smoother than normal grass, with natural bumps and cracks. He said hybrid turf is cheaper to install from the start than synthetic turf and lasts a few years, although it requires more maintenance.
Grasslands may be sufficient for many communities. While some stakeholders figure out how to Maintain grass more sustainablyOther scientists are working to improve the grass. “If the same amount of engineering is put into natural grass, it’s all we can do,” Brownbill said. Not all grass is the same.
“There are high heat-resilient grasses; there are shade-resilient grasses; there are high-wear-resistant grasses,” Brownbill said. “[Municipalities] “Basically using 100-year-old technology… the same grass varieties that existed 100 years ago.”
Editor’s note: This article was prepared as part of Dalla Lana Fellowship in Journalism and Health Impact Program at the University of Toronto.
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