Fact Sheet on Crumb Rubber Used in Synthetic Turf
Synthetic turf fields using crumb rubber have been installed in many athletic and playing fields throughout New York City, the United States and the world. This fact sheet provides information on questions often asked about the rubber used in the synthetic turf fields.
Q: Why is synthetic turf used in NYC?
A: Athletic and playing fields in NYC parks are made of different materials, ranging from dirt, grass and asphalt to synthetic turf. Synthetic turf is a man-made product and is mostly installed in fields that are heavily used. Synthetic turf fields are used in NYC parks because they:
- provide even playing surfaces
- have padding that helps prevent injuries
- need no watering or mowing
- use no fertilizers or pesticides
- can be used year-round and in most weather
- do not need to be closed to protect or re-sod grass
- last a long time with little maintenance
Q: What are synthetic turf fields made of?
A: A: The NYC Parks Department uses different kinds of synthetic turf depending on how and where it will be used. Most of the synthetic turf fields contain crumb rubber infill along with padding and drainage systems. Other synthetic fields are made of carpet-style materials and do not use crumb rubber. The carpet-style fields are used primarily in the conversion of asphalt fields to synthetic fields.
Crumb rubber fields are made of the following materials:
- A bottom layer composed of plastic sheeting.
- Middle layers composed of crushed stones with plastic tubing for drainage and rubber padding for shock absorbance
- A top layer composed of plastic mesh with soft, plastic strands that resemble blades of grass
- Crumb rubber infill, made from recycled tires, is added to the top layer to provide extra padding and keep the grass upright. Sand is sometimes mixed with the crumb rubber.
Currently, about 13% of the Parks Department's 952 playing fields are synthetic turf (with 70% grass and 17% asphalt).
Q: What chemicals can be found in the synthetic turf crumb rubber?
A: The crumb rubber used in synthetic turf is mainly composed of recycled tires, which contain man-made and natural rubber. Very small amounts of chemicals called polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs) have been found in the crumb rubber. Crumb rubber can also contain small amounts of heavy metals such as zinc and iron.
Q: Can people be exposed to the chemicals found in crumb rubber?
A: Although the potential for significant exposure to the chemicals in crumb rubber is very low, there are three possible ways for people to have contact with these chemicals on artificial turf fields:
- Accidentally ingesting small amounts of crumb rubber by putting fingers in the mouth or not washing hands before eating after playing on the fields
- Breathing in dust and vapors while playing on the fields. Crumb rubber may become dust as it wears and the rubber may give off some vapors.
- Direct skin contact with the crumb rubber.
Q: Are any health effects associated with these chemicals?
A: Several scientific research studies carried out in the United States and Europe have assessed potential exposures and health risks for people using turf fields containing crumb rubber. According to the Health Department's review of these research findings, health effects are unlikely from exposure to the levels of chemicals found in synthetic turf. At much higher levels, these chemicals can cause serious health effects. In laboratory studies, PAHs have caused organ damage and cancer in animals. Some PAHs may also pose a cancer risk for people exposed to high levels for long periods. VOCs are a mixture of chemicals that can cause eye, nose, throat and skin irritation. At high levels, some VOCs can also cause organ damage.
Q: Can people be exposed to these chemicals from other sources?
A:The PAHs and VOCs found in crumb rubber are very common in the urban environment. People can be exposed by breathing or eating or by getting dirt or dust on their skin. Rubber dust from car tires is a source of city air pollution and soil pollution. PAHs are present in exhaust, smoke, soot, urban soil and char-broiled foods. VOCs are released into the air from gasoline, paint, building materials and many other sources.
Q: Does the heat generated by synthetic turf pose a health risk to users?
A: Like asphalt, the crumb rubber in synthetic turf fields absorbs heat from the sun and gets hotter than dirt or natural grass. On hot days, some synthetic turf fields may be too hot to play on. To protect yourself from the heat, drink lots of water, wear light and loose fitting clothes, always wear shoes, take breaks often, and exercise moderately. If you experience symptoms of heat related illness, such as dizziness, weakness, headache, nausea, vomiting or muscle cramps, move to a shaded area, drink water and rest. Seek medical attention if you do not feel better. It's especially important that adults supervising children take precautions on hot days.
Q: Are people who play on synthetic turf fields at risk of bacterial infections?
A: Bacterial infections, such as methicillin-resistant S. aureus (MRSA), have not been shown to be caused by synthetic turf fields. Bacterial infections among athletes are due mainly to physical contact and sharing contaminated towels or sports equipment. Coaches and players should be aware of the potential for MRSA transmission and infection among athletes. All skin cuts or abrasions should be washed with soap and water and covered immediately. School athletic departments and sports leagues, should use good hygienic practices and prohibit the sharing of towels and equipment that rubs against bare skin.
Q: Recently, lead was identified in some synthetic turf fields in New Jersey. Has lead been found in synthetic turf fields in NYC?
A:Some older carpet-style fields in New Jersey were found to contain lead in the carpet fibers. These fields do not contain crumb rubber. They resemble a flat carpet and are made of nylon fibers. Lead dust can be created through wear and tear if these nylon fields are not well maintained. The dust may be swallowed or inhaled if it becomes airborne. The NYC Parks Department maintains two carpet-style fields similar to the ones in New Jersey. Testing of the two NYC fields found the nylon fibers to be intact, and no lead dust hazards were identified.
Q: Should people continue to use synthetic turf fields with crumb rubber?
A: Yes. Regular physical activity is one of the most important parts of a healthy lifestyle. Synthetic turf fields allow access to open spaces for sports and physical activities. After any outdoor activity, people should wash their hands before eating or drinking. On very hot days, users should limit activities, take rest breaks and drink water.
Q: Where can I get more information?
A: The NYC Health Department has issued a report on potential exposures and health effects related to synthetic turf fields. The report identified heat-related illness as the primary health concern and recommended steps for preventing heat-related illness. The report concluded that the potential for exposure to the chemicals found in the crumb rubber infill of synthetic fields is probably too small to increase the risk for any health effects. Read the full report (PDF).
