Human exposure to polycyclic aromatic hydrocarbons and metal(oid)s from artificial turf and synthetic/recycled rubber materials: Insights from dermal bioaccessibility and risk assessment.

Synthetic and recycled rubber materials and artificial turf are widely used in public recreational settings, raising concerns about human exposure to polycyclic aromatic hydrocarbons (PAHs) and metal(oid)s. In this study, these contaminants were analysed in 37 samples, including rubber-based playground and athletic track flooring, as well as artificial turf plastic fibres and crumb rubber infill for football pitches, comprising both in-use and new materials. As dermal contact is the main exposure pathway, dermal bioaccessibility was assessed using an in vitro physiologically based extraction test (PBET) with synthetic human sweat and sebum fluid, simulating compound dissolution at the skin surface. Styrene-butadiene rubber (SBR) materials exhibited the highest PAH levels (mean 15770 ng g-1), with pyrene and benzo(g,h,i)perylene predominating across samples. Metal(oid)s concentrations were generally higher than PAHs, with Al, Fe, and Zn dominating the elemental profile, and the highest values observed in ethylene-propylene-diene monomer (EPDM) samples (mean 83100 μg g-1), although only three EPDM samples were analysed. PAH dermal bioaccessibility ratios ranged from 1.1% to 6.2%, whereas metal(oid) bioaccessibility showed a wider range, from 0.07% for Al in EPDM to 31.6% for As in artificial turf fibres (polyethylene/polypropylene), despite their low pollutant levels. Furthermore, dermal carcinogenic and non-carcinogenic risks assessed using bioaccessible concentrations following the Office of Environmental Health Hazard Assessment model remained below the selected risk thresholds across all evaluated population groups. The use of bioaccessible fractions would provide a more realistic estimate of exposure by accounting for compound-specific release from materials into the simulated dermal fluid and the resulting fraction of contaminants potentially available for dermal uptake.