The Dirt on Synthetic Turf

The 2026 Men’s FIFA World Cup final will shake up the New York Metro Area in numerous ways. Notably, MetLife Stadium in East Rutherford, NJ, needs a renovation: FIFA requires the stadium to swap out its synthetic turf field for real grass. In between the plastic blades of grass, synthetic turf fields are filled with ground-up tires, called “crumb rubber” in place of where dirt would be. 

A new state bill questions the health hazards of crumb rubber. Sports fans question players’ safety on synthetic turf. In either case, turf fields are quickly replacing grass in New York’s parks — raising questions about a third impact: the environment. 

If passed, Int. 7158, sponsored by Assemblymember Grace Lee, would require a comprehensive environmental and public health study of crumb rubber. First introduced in 2021, the bill arsenic, cadmium, chromium, lead, vanadium, zinc, and acetone as hazardous materials in crumb rubber with potential adverse health effects such as cancer, birth defects, and nervous system damage. 

As part of the bill, all installation of synthetic turf fields containing crumb rubber would be immediately suspended throughout the state. 

Assemblymember Lee, whose district includes the Lower East Side where eight new synthetic turf baseball fields were installed, did not immediately respond to a request for comment. 

Synthetic turf is a new and rapidly developing technology which makes it hard to study. What was used in synthetic turf fields five years ago might look vastly different from new synthetic turf proposals. The NYC Health website lists some of the concerns with crumb rubber, noting that the city would consider replacing crumb rubber with a new form of synthetic turf. There are 202 synthetic turf systems in New York City. A 2018 report by the New York State Department of Health lists heat stress as a concern with the black, heat-radiating crumb rubber but at the time found no other health risks. 

To maintain consistency between playing fields, FIFA, the soccer's world governing body, requires all FIFA matches to be played on real grass. FIFA has a rigorous 120-page “Natural Turf Guidelines” to ensure that all soccer pitches end up nearly identical. This decision isn’t just for the similarities, synthetic turf poses safety concerns as well: ​​athletes seem to sustain more non-contact injuries on synthetic turf than on natural grass. 

When the Jets’ Aaron Rodgers tore his achilles tendon in September 2023 the football world suddenly had an interest in grass. Many fans argued that Rodgers wouldn’t have been injured if he was playing on real grass instead of synthetic turf, others suggested his injury was inevitable no matter the playing surface. Multiple studies have found an increased rate of ACL injuries on synthetic turf playing fields for football players and female soccer players. Multiple studies have also found the opposite to be true, that synthetic turf is safer than grass — though many were sponsored by the artificial turf industry. 

Debates continue today on the safety of synthetic turf versus real grass. About half of all the NFL stadiums use synthetic turf and nearly all new park construction in New York involves a synthetic turf playing field. Without conclusive evidence of player safety, the benefit of a synthetic turf field is that it’s easy to maintain. In arid environments where water is a concern, synthetic turf fields require no water, and in cold-weather climates where grass might die off mid-season, the synthetic turf fields would stay green. 

The effect of synthetic turf fields on the environment, though, is worth consideration. The crumb infill mentioned in Assemblymember Lee’s bill contains PFAs, also known as “forever chemicals” which are slowly being banned in other sectors in the state. PFAs can leech into waterways and contaminate drinking water. Today, about 97% of Americans with PFAs in their body. Scientists are studying the direct effects of having PFAs in the body as people who live near areas with high PFA contamination report more instances of cancer. 

Synthetic turf fields are organized into layers. There is a layer of crushed concrete or granite, topped by a shock-absorbing layer of plastic, then a synthetic fabric layer to prevent weeds from growing, and finally, the artificial grass filled in with crumb rubber. Many synthetic systems require a drainage system installed because the layers of plastic are unable to drain rainwater runoff. 

Advocacy group East River Park Action (ERPA) is rallying to get Assemblymember Lee’s bill passed. The group argues that natural grass keeps temperatures lower, reducing the risk of heat stress, doesn’t leech pollutants, and absorbs water as a natural flood mitigation system in a flood-prone city. They found cases of synthetic turf field infill flowing into the East River during storms. ERPA isn’t the only group against it, nearly 300 locals in Washington Heights sent a letter to officials in protest of a new synthetic turf field. 

“California law now allows cities and counties to ban synthetic turf. Boston has banned it. We can too,” ERPA wrote in their synthetic turf fact sheet. New Jersey’s Department of Environmental Protection recently raised concerns about the environmental and health impact of PFAS in synthetic turf and the EPA recently placed near-zero limits on PFAS in drinking water. 

One ERPA member, Marcella Durand, wrote “We advocate halting any use of artificial turf in New York City parks. We advocate the NYC Parks be better funded and staffed […] But more than anything, we advocate that our green spaces not cause active harm to humans and all living things on the planet.”