Accumulation, translocation and impact of TiO2 nanoparticles in wheat (Triticum aestivum spp.): Influence of diameter and crystal phase

► TiO2-NP diameter, but not crystallinity, influences their transfer in plant tissues. ► Wheat roots accumulate TiO2-NPs with diameter up to 36 nm but not 140 nm TiO2-NPs. ► TiO2-NPs with diameter lower than 36 nm are translocated from wheat root to shoot. ► A 100 mg/L TiO2-NP wheat root exposure leads to Ti root content up to 110 μg/g d.wt. ► Exposure of wheat to the smallest TiO2-NP induces increased root elongation.