Titanium dioxide’s carcinogenicity when inhaled is well-known from occupational settings during the production of titanium dioxide (TiO2) powders or in the manufacture of products containing the substance and reported in animal studies involving inhalation of titanium dioxide particles. Researchers have warned of possible future consequences caused by a poorly regulated use of nanotechnology in textiles, expanding on potential human health and environmental effects.
Although originally classified as biologically inert, there is a growing body of evidence on the toxicity of titanium dioxide to humans and non-target organisms … Artificial sweat was also used to test the concentration of the silver and TiO2 released from fabrics. The release rate was found to depend on the concentration of nanomaterials in the fabric and the pH of sweat.”
The International Agency for Research on Cancer classifies titanium dioxide as a Group 2B carcinogen.
The state of California regulates titanium dioxide in the form of airborne particles measuring 10 micrometers or less, stating: "...titanium dioxide (airborne, unbound particles of respirable size) is on the Proposition 65 list because it can cause cancer. Exposure to titanium dioxide may increase the risk of cancer."
Titanium dioxide is used as a pigment in paints. The production procedure is highly polluting because of the large quantities of wastes which are often thrown into the sea where, by chemical reaction, they can be transformed into 'red mud'. These wastes destroy living organisms such as plankton and they can also impregnate the flesh of fish used for human consumption.
In a study of 12 face masks, every mask contained titanium dioxide (TiO2) particles in at least one layer, at levels that exceeded the acceptable exposure level. It is used in face mask textiles to improve stability to ultraviolet light and as a white colorant and matting agent. Nanofibers containing titanium dioxide are used to make antimicrobial filters, often in combination with silver and graphene, while titanium dioxide nanoparticle coatings may also be applied to cotton fabric to enhance a mask's antibacterial properties.