Zhu et al. were the first to provide evidence that TiO₂ NPs (21 nm) can transfer from daphnia to zebrafish by dietary exposure. Hence, dietary intake could be a major route of exposure to NPs for high trophic level aquatic organisms. Ecological research should therefore focus, not only on the concentration of NPs in the environment, but also on its bioconcentration, bioaccumulation and biomagnification. In addition it has been shown that TiO₂ NPs can increase accumulation of other environmental toxicants: enhanced accumulation of cadmium (Cd) and arsenic (As) was found in carp in the presence of TiO₂ NPs. The strong adsorption capacity for Cd and As was explained by the large specific surface area and strong electrostatic attraction of TiO₂ NPs that contribute to facilitated transport into different organs.

Lithopone in fillers, adhesives, joints and sealants

The vitaminB2@TiO₂NPs were obtained at room temperature, by a method developed after trying several ratios of reactants. Briefly, 0.02 g of P25TiO₂NPs were dispersed in 1 mL of ultra-pure water and stirred in a Vortex. Next, 200 μl of vitamin B2 dissolved in ultra-pure water (5.3 × 10⁻³ M) were added to 200 μL of P25TiO2NPs and the mixture was ultrasonicated for 1 hour to achieve a deep-yellow homogeneous suspension. The pellet obtained after centrifuging the suspension for 10 min at 4500 rpm was resuspended in ultrapure water, centrifuged again, and then lyophilized.