EPDM Infill for Synthetic Turf

Ethylene propylene diene terpolymer (EPDM) is a synthetic rubber used to make roofing membranes, sheet roofing, wire and cable, seals and gaskets, diaphragms, tires and tubes, rubber flooring, and a variety of hoses. It is also used as infill in athletic turf, and is marketed as an alternative to tire-derived crumb rubber infill because of its high resistance to heat and weathering. While many studies have been conducted on tire-derived crumb rubber that detected residual levels of a large number of hazardous chemicals (including VOCs, phthalates, PAHs, heavy metals, and alkylphenols), fewer studies have been conducted on EPDM infill to evaluate the levels of these same classes of chemicals, so at the time of this research, it was not possible to determine if they are common. Furthermore, most of the existing studies on residual chemicals found in EPDM are more than ten years old, highlighting the need for updated research on this topic. EPDM is a vulcanized rubber that can be produced as black granules, which contains carbon black as a pigment and filler. It can also be produced in a variety of other colors that do not contain high levels of carbon black, such as beige and green. In addition to aesthetics, the lighter colors allow it to maintain a lower surface temperature on hot days. Although some infill may be manufactured from recycled EPDM, most products surveyed were composed entirely of virgin rubber. Consequently, this CP focuses on green-colored EPDM infill manufactured from virgin rubber and marketed for athletic turf. EPDM may also contain flame retardants or biocides, which could both introduce additional hazards into the product, though these were not found to be common.