Leaching of zinc from rubber infill on artificial turf (football pitches)
Uitloging van zink uit rubbergranulaat op kunstgras voetbalvelden
26 May 2012, PDF |
55 pages |
RIVM Report 601774001
Many artificial football pitches are treated with a rubber infill made of recycled tyres. From this material zinc leaches to the soil, groundwater and surface water. [This can present significant environmental risks, particularly for aquatic life.] Human health risks posed by leaching of zinc are negligible as zinc concentrations in the water do not exceed drinking water standards. In the present study a targeted environmental risk assessment is performed for zinc in rubber infill on football pitches. The main focus was on the release of zinc from the rubber infill, i.e. the zinc load, the distribution of zinc between the soil, groundwater and surface water. Ageing of the rubber crumbs appears to be of major importance for estimating zinc releases. The study used simple calculation models and realistic input values, and assumed an increasing zinc release due to ageing of the rubber. Environmental quality standards for zinc in surface water and groundwater are exceeded. The study shows that zinc from the rubber infill is either emitted mainly to the surface water (when a drainage system has been constructed on clay or peat soils) or mainly to groundwater (in naturally well-drained sandy soils). The study showed that the predicted concentrations of zinc in soil, under typical Dutch drainage conditions, also exceeds environmental quality standards. The predicted zinc load is relatively high. For comparison, the zinc criteria in the Dutch Building Materials Decree are exceeded, and the leaching rate of zinc from rubber crumbs is up to 20 times greater than the local leaching of zinc from agricultural applications of manure and pesticides. The results can be used to assist decision-making on the use of rubber infill on football pitches where an environmental risk assessment is required.