<P> Both the rubber granules (often made from recycled waste tires) and the synthetic fibres of artificial turf are subject to wear and can be washed into the environment . Second only to tire and road wear particles (TRWP) that make up a large portion of the fine road debris, the rubber granulate from artificial turf infill constitutes a significant source of rubber pollution . Fragments from the artificial reeds make their way into the environment as microplastics pollution in both marine as well as soil environments . </P> <P> A number of health and safety concerns have been raised about artificial turf . Friction between skin and older generations of artificial turf can cause abrasions and / or burns to a much greater extent than natural grass . Artificial turf tends to retain heat from the sun and can be much hotter than natural grass with prolonged exposure to the sun . There is some evidence that periodic disinfection of artificial turf is required as pathogens are not broken down by natural processes in the same manner as natural grass . Despite this, a 2006 study suggests certain microbial life is less active in artificial turf . </P> <P> There is evidence showing higher rates of player injury on artificial turf . In a study performed by the National Football League Injury and Safety Panel, published in the October 2012 issue of the American Journal of Sports Medicine, Elliott B. Hershman et al. reviewed injury data from NFL games played between 2000 and 2009 . "...the injury rate of knee sprains as a whole was 22% higher on FieldTurf than on natural grass . While MCL sprains did not occur at a rate significantly higher than on grass, rates of ACL sprains were 67% higher on FieldTurf ." Metatarsophalangeal joint sprain, known as "turf toe" when the big toe is involved, is named from the injury being associated with playing sports on rigid surfaces such as artificial turf and is a fairly common injury among professional American football players . Artificial turf is a harder surface than grass and does not have much "give" when forces are placed on it . </P> <P> There is also significant concern regarding a plausible link between artificial turf and cancer . Some artificial turf uses infill such as silicon sand and / or granulated rubber, referred to as "crumb rubber". Some granulated rubber is made from recycled car tires and may carry heavy metals which can leach into the water table . As early as 2007, a moratorium on the use of ground - up rubber tires in fields and playgrounds was recommended based on health concerns . </P>

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