barium sulphate is insoluble in water

TiO2 NPs appeared to be more toxic to nematode Caenorhabditis elegans than submicron-sized TiO2.  At a concentration of 1 mg/l, 7 nm particles affected its fertility and survival rate and were more toxic than 20 nm anatase particles. Similarly, Hu et al. showed that rutile particles (10–20 nm), at concentrations above 1 g/kg soil, can be bio-accumulated in earthworms, where they induce oxidative stress, inhibit the activity of cellulase and induce DNA and mitochondrial damage.

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Overall, titanium dioxide plays a vital role in both industrial applications and environmental protection. With China leading the way in the production of high-purity titanium dioxide, the country is well-positioned to meet the growing demand for this essential mineral. By continuing to invest in research and development, China can further enhance its capabilities in titanium dioxide production and contribute to the advancement of global technological innovation.

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