titanium dioxide is a precipitate

The production process of titanium dioxide involves several stages, starting with the extraction of raw materials from mineral ores such as ilmenite, rutile, and anatase. These ores are then processed through various methods, including the sulfate and chloride processes, to produce high-purity titanium dioxide powder. The sulfate process involves treating the ore with sulfuric acid to extract titanium dioxide, while the chloride process uses chlorine gas to produce a purer form of the pigment.

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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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