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No acute effects of nano-sized TiO2 were observed in Danio rerio (zebrafish) embryos. Exposure of rainbow trout to TiO2 NPs triggered lipid peroxidation, influence on the respiratory tract, disturbance in the metabolism of Cu and Zn, induction of intestinal erosion  and accumulation in kidney tissue. Linhua et al. exposed juvenile carp to 100 and 200 mg/ml of particles and TiO2 observed no mortality. However, the fish suffered from oxidative stress and pathological changes in gill and liver. In the infaunal species Arenicola marina, exposure to TiO2 NPs in sediment caused sub-lethal effects including decrease in casting rate and increase in cellular and DNA damage. Aggregated particles were visible in the lumen of the gut, but no uptake through the gut or the skin was observed.

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Maintaining consistency and quality during scale-up is one of the most challenging aspects of nano-TiO2 production. The factory must adhere to stringent quality control measures, using advanced analytical techniques like X-ray diffraction (XRD) and transmission electron microscopy (TEM) to ensure the purity and uniformity of the nanoparticles. Additionally, environmental safety and health considerations are paramount, given the potential risks associated with nanomaterials.

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