Durabo White, 24.5 per cent zinc sulphide, 51 per cent barium sulphate, 18 per cent white clay, 5.5 per cent infusorial earth.
Price and AvailabilityAlthough the evidence for general toxic effects was not conclusive, on the basis of the new data and strengthened methods our scientists could not rule out a concern for genotoxicity and consequently they could not establish a safe level for daily intake of TiO2 as a food additive.
Nano-sized TiO2 generally shows low or no acute toxicity in both invertebrates and vertebrates. However, exposure of Daphnia magna to 20 ppm TiO2 for 8 consecutive days was found to cause 40 % mortality. Zhu et al. showed minimal toxicity to D. magna after 48 h exposure, while upon chronic exposure for 21 days, D. magna suffered severe growth retardation and mortality. A significant amount of nano-sized TiO2 was found also accumulated in the body of the animals. Similar findings with coated nano-sized TiO2 (T-Lite™ SF, T-Lite™ SF-S and T-Lite™ MAX; BASF SE) were reported by Wiench et al. Biochemical measurements showed that exposure to TiO2 NPs induces significant concentration-dependent antioxidant enzyme activities in D. magna. Lee et al. showed that 7 and 20 nm-sized TiO2 induced no genotoxic effect in D. magna and in the larva of the aquatic midge Chironomus riparius.
