Tyre granulate on the loose; How much escapes the turf? A systematic literature review

Tyre granulate used as infill for artificial turf is hailed by some as a good example of reuse, while others see it as a baleful means to dispose of discarded tyres. Because the particles are applied loosely to the surface, they will inevitably disperse into the environment. The possible environmental and health impacts of the particles are a source of societal concern. In response to this, policies to limit particle losses are being developed at the European level. To make informed decisions, data on the quantity of tyre granulate released into the environment are required. So far, however, there are no systematic reviews on or estimates of these losses. The aim of the present study was to identify the various pathways through which infill leaves a football turf and, subsequently, to estimate the quantity of infill leaving the turf by each of these pathways. Data on the pathways including the associated volumes were collected in a systematic literature review following the PRISMA method. The quality of the evidence reported in the retrieved literature was assessed using the GRADE method. The resulting pathways and corresponding quantities were captured in a mass balance. This study estimates that, without mitigation measures, approximately 950 kg/year (min. 570 kg/year, max. 2280 kg/year) of infill leaves the surface of an average artificial football turf via known pathways. Clearing snow can result in an additional loss of 830 kg/year (min. 200 kg/year, max. 2760 kg/year) of infill material. To mitigate the dispersion of infill, one could focus on snow removal, brushing and granulate picked up by players. Mitigation measures for these pathways are well-established and relatively easy to implement and maintain. Although the amount of granulate picked up from the turf by players is relatively small, the measure will promote environmental awareness among the players.