Artificial turf is surface of synthetic fibers resembling natural grass. It is widely used for sports fields for being more hard-wearing and resistant than natural surfaces. Most use infills of crumb rubber from recycled tires; this use is controversial because of concerns that the tires contain carcinogens, though research into the issue is ongoing. [1]
An unpublished study by Rutgers University examined crumb rubber from synthetic fields in New York City. It found six possibly carcinogenic polycyclic aromatic hydrocarbons at levels excessive to state regulations. The researchers warned that the findings could have been made inaccurate by solvent extraction used to release the chemicals from the rubber. [2]
In a statistical study of the list of soccer players with cancer provided by UW coach Amy Griffin, public health researchers for the State of Washington found that the rates of cancer were actually lower than was estimated for the general population. While they did not state any conclusions on the safety of this form of artificial turf, they did recommend that players not restrict their play due to the presumed health benefits of being active. [3]
In 2007, the California Office of Environmental Health Assessment (OEHHA) simulated interactions children can have with after coming into direct contact with artificial turf. Results showed that five chemicals, including four polycyclic aromatic hydrocarbons (PAHs), were found in samples. One of these compounds, chrysene, was present at levels higher than the standard established by OEHHA. Chrysene is a known carcinogen, meaning it can increase the risk of a child developing cancer. [4]
In late 2015, the United States Congress' House Energy and Commerce Committee ordered for the Environmental Protection Agency (EPA) to investigate a link. As of 2016, the EPA, the Consumer Product Safety Commission and the Centers for Disease Control and Prevention were investigating. [5]
In 2018, a study commissioned by the Dutch minister of Health, Welfare and Sport from the Dutch National Institute for Public Health and the Environment found that "our findings for a representative number of Dutch pitches are consistent with those of prior and contemporary studies observing no elevated health risk from playing sports on synthetic turf pitches with recycled rubber granulate". [6]
A 2019 Yale study showed that there were 306 chemicals in crumb rubber and that 52 of these chemicals were classified as carcinogens by the Environmental Protection Agency (EPA). They stated that "a vacuum in our knowledge about the carcinogenic properties of many crumb rubber infill. The crumb rubber infill of artificial turf fields contains or emits chemicals that can affect human physiology." [7]
In 2020, the European Risk Assessment Study on Synthetic Turf Rubber Infill was completed; published in Science of the Total Environment , this was a scientific study funded by companies and industry association from the tyre granulate supply chain, drawing on data from diverse parts of Europe. The researchers concluded that "there are no relevant health risks associated with the use of synthetic turfs with ELT-derived infill material". [8]
A 2022 study published in the same journal analyzed the composition of synthetic turf football pitches from 17 countries. It confirmed the presence of "hazardous substances in the recycled crumb rubber samples collected all around the world" including PAHs of high and very high concern. The study concluded that different stakeholders "must work on a consensus to protect not only human health but also the environment, since there is evidence that crumb rubber hazardous chemicals can reach the environment and affect wildlife." The paper did not, however, discuss cancer risk in any detail. [9]
In March 2023, investigative reporters from the Philadelphia Inquirer bought souvenir samples of the old Veterans Stadium AstroTurf used from 1977–81 and commissioned diagnostics through the Eurofins Environmental Testing laboratory. The resulting lab report linked per- and polyfluoroalkyl substances (PFAS) to the turf. Six former Philadelphia Phillies who played at Veterans Stadium, home to the team from 1971 to 2003, died from glioblastoma, an aggressive brain cancer: Tug McGraw, Darren Daulton, John Vukovich, Johnny Oates, Ken Brett, and David West. [10]
Nigel Maguire, formerly a chief executive for the National Health Service in Cumbria, claims that his son, a goalkeeper, could have developed Hodgkin's lymphoma by playing on an artificial surface. He has called for a ban on the surfaces, saying "It is obscene so little research has been done." [11]
In 2014, Amy Griffin, soccer coach at the University of Washington, surveyed American players of the sport who had developed cancer. Of 38 players, 34 were goalkeepers, a position in which diving to the surface makes accidental ingestion or blood contact with crumb rubber more likely, Griffin has asserted. Lymphoma and leukemia, cancers of the blood, predominated. [12]
FIFA, the world governing body of association football (soccer), has stated that the evidence weighs in favour of artificial pitches being safe. The Football Association of England stated in February 2016 that they were observing reports and conducting their own research on the issue. [11]
Coal tar is a thick dark liquid which is a by-product of the production of coke and coal gas from coal. It is a type of creosote. It has both medical and industrial uses. Medicinally it is a topical medication applied to skin to treat psoriasis and seborrheic dermatitis (dandruff). It may be used in combination with ultraviolet light therapy. Industrially it is a railroad tie preservative and used in the surfacing of roads. Coal tar was listed as a known human carcinogen in the first Report on Carcinogens from the U.S. Federal Government, issued in 1980.
Piperonyl butoxide (PBO) is a pale yellow to light brown liquid organic compound used as an adjuvant component of pesticide formulations for synergy. That is, despite having no pesticidal activity of its own, it enhances the potency of certain pesticides such as carbamates, pyrethrins, pyrethroids, and rotenone. It is a semisynthetic derivative of safrole and is produced from the condensation of the sodium salt of 2-(2-butoxyethoxy) ethanol and the chloromethyl derivative of hydrogenated safrole (dihydrosafrole); or through 1,2-Methylenedioxybenzene.
1,3-Butadiene is the organic compound with the formula CH2=CH-CH=CH2. It is a colorless gas that is easily condensed to a liquid. It is important industrially as a precursor to synthetic rubber. The molecule can be viewed as the union of two vinyl groups. It is the simplest conjugated diene.
Artificial turf is a surface of synthetic fibers made to look like natural grass, used in sports arenas, residential lawns and commercial applications that traditionally use grass. It is much more durable than grass and easily maintained without irrigation or trimming, although periodic cleaning is required. Stadiums that are substantially covered and/or at high latitudes often use artificial turf, as they typically lack enough sunlight for photosynthesis and substitutes for solar radiation are prohibitively expensive and energy-intensive. Disadvantages include increased risk of injury especially when used in athletic competition, as well as health and environmental concerns about the petroleum and toxic chemicals used in its manufacture.
Chloroprene (IUPAC name 2-chlorobuta-1,3-diene) is a chemical compound with the molecular formula CH2=CCl−CH=CH2. Chloroprene is a colorless volatile liquid, almost exclusively used as a monomer for the production of the polymer polychloroprene, better known as neoprene, a type of synthetic rubber.
Atrazine is a chlorinated herbicide of the triazine class. It is used to prevent pre-emergence broadleaf weeds in crops such as maize (corn), soybean and sugarcane and on turf, such as golf courses and residential lawns. Atrazine's primary manufacturer is Syngenta and it is one of the most widely used herbicides in the United States, Canadian, and Australian agriculture. Its use was banned in the European Union in 2004, when the EU found groundwater levels exceeding the limits set by regulators, and Syngenta could not show that this could be prevented nor that these levels were safe.
Hexavalent chromium (chromium(VI), Cr(VI), chromium 6) is any chemical compound that contains the element chromium in the +6 oxidation state (thus hexavalent). It has been identified as carcinogenic, which is of concern since approximately 136,000 tonnes (150,000 tons) of hexavalent chromium were produced in 1985. Hexavalent chromium compounds can be carcinogens (IARC Group 1), especially if airborne and inhaled where they can cause lung cancer.
Crumb rubber is recycled rubber produced from automotive and truck scrap tires. During the recycling process, steel and tire cord (fluff) are removed, leaving tire rubber with a granular consistency. Continued processing with a granulator or cracker mill, possibly with the aid of cryogenics or by mechanical means, reduces the size of the particles further. The particles are sized and classified based on various criteria including color. The granulate is sized by passing through a screen, the size based on a dimension or mesh. Crumb rubber is often used in artificial turf as cushioning.
Bromodichloromethane is a trihalomethane with formula CHBrCl2. It is a colorless, nonflammable liquid which will dissolve in water, or evaporate in air. Most of the chemical is produced through the chlorine disinfection process, and as a result it can occur in municipally-treated drinking water. It is also produced in small quantities by algae in the oceans. According to the CDC, levels normal in drinking water are not known to cause health problems, but it has been classified by the US EPA as a probable human carcinogen.
Rubber mulch is a type of mulch used in gardening and landscaping that is made from recycled rubber, most often crumb rubber sourced from waste tires.
Tire recycling, or rubber recycling, is the process of recycling waste tires that are no longer suitable for use on vehicles due to wear or irreparable damage. These tires are a challenging source of waste, due to the large volume produced, the durability of the tires, and the components in the tire that are ecologically problematic.
The Office of Environmental Health Hazard Assessment, commonly referred to as OEHHA, is a specialized department within the cabinet-level California Environmental Protection Agency (CalEPA) with responsibility for evaluating health risks from environmental chemical contaminants.
The Del Amo Superfund Site is located in southern Los Angeles County between the cities of Torrance and Carson. It is a U.S. EPA Region 9 Superfund Site. The waste-disposal site of a rubber manufacturer is one of 94 Superfund Sites in California as of November 29, 2010.
2,4-Dichlorophenoxyacetic acid is an organic compound with the chemical formula Cl2C6H3OCH2CO2H. It is usually referred to by its ISO common name 2,4-D. It is a systemic herbicide that kills most broadleaf weeds by causing uncontrolled growth, but most grasses such as cereals, lawn turf, and grassland are relatively unaffected.
The substitution of dangerous chemicals in the workplace is the process of replacing or eliminating the use chemicals that have significant chemical hazards. The goal of the substitution process is to improve occupational health and safety and minimize harmful environmental impacts. The process can be time-consuming; assessments of dangers, costs, and practicality may be necessary. Substituting hazardous chemicals follows the principles of green chemistry and can result in clean technology.
Micronized rubber powder (MRP) is classified as fine, dry, powdered elastomeric crumb rubber in which a significant proportion of particles are less than 100 μm and free of foreign particulates. MRP particle size distributions typically range from 180 μm to 10 μm. Narrower distributions can be achieved depending on the classification technology.
The Waste Disposal Inc. Superfund site is an oil-related contaminated site in the highly industrialized city of Santa Fe Springs in Los Angeles County, California. It is approximately 38 acres (15 ha), with St Paul's high school immediately adjacent to the northeast corner of the site. Approximately 15,000 residents of Santa Fe Springs obtain drinking water from wells within three miles (4.8 km) of the site.
Tire recycling in the United States is the disposal and reuse of waste tires.
Glyphosate-based herbicides are usually made of a glyphosate salt that is combined with other ingredients that are needed to stabilize the herbicide formula and allow penetration into plants. The glyphosate-based herbicide Roundup was first developed by Monsanto in the 1970s. It is used most heavily on corn, soy, and cotton crops that have been genetically modified to be resistant to the herbicide. Some products include two active ingredients, such as Enlist Duo which includes 2,4-D as well as glyphosate. As of 2010, more than 750 glyphosate products were on the market. The names of inert ingredients used in glyphosate formulations are usually not listed on the product labels.
Rubber pollution, similar to plastic pollution, occurs in various environments, and originates from a variety of sources, ranging from the food industry processing chain to tire wear. Synthetic and natural rubber dust and fragments now occur in food, airborne as particulates in air pollution, hidden in the earth as soil pollution, and in waterways, lakes and the sea.