For definition of Groups, see Preamble Evaluation.
VOL.: 47 (1989) (p. 307)
Chem. Abstr. Name: Titanium dioxide
Titanium dioxide is a white pigment produced mainly from ilmenite (iron titanate) and natural rutile (titanium dioxide). It is widely used in paints, paper, plastics, ceramics, rubber, inks and a variety of other products. Occupational exposure to titanium dioxide during its production, the production of paints, in painting trades and during other industrial use is likely to be extensive, but there is a paucity of data on levels, both occupational and environmental.
Titanium dioxide was tested for carcinogenicity by oral administration in one strain of mice and in one strain of rats, by inhalation in two strains of rats, by intratracheal administration in one strain of hamsters, by subcutaneous injection in one strain of rats and by intraperitoneal administration in one strain of male mice and two strains of female rats. Increased incidences of lung adenomas in rats of both sexes and of cystic keratinizing lesions diagnosed as squamous-cell carcinomas in female rats were observed in animals that had inhaled the high but not the low doses of titanium dioxide. Oral, subcutaneous, intratracheal and intraperitoneal administration did not produce a significant increase in the frequency of any type of tumour in any species. Intratracheal administration of titanium dioxide in combination with benzo[a]pyrene to hamsters resulted in an increase in the incidence of benign and malignant tumours of the larynx, trachea andlungs over that in benzo[a]pyrene-treated controls.
The only available epidemiological studyprovided inconclusive results.
Titanium dioxide did not induce morphological transformation in mammalian cells or mutation in bacteria.
There is inadequate evidence for the carcinogenicity of titanium dioxide in humans.
There is limited evidence for the carcinogenicity of titanium dioxide in experimental animals.
Titanium dioxide is not classifiable as to its carcinogenicity to humans (Group 3).
For definition of the italicized terms, see Preamble Evaluation.
Last updated 01/21/98
See Also: Toxicological Abbreviations Titanium dioxide (ICSC) Titanium dioxide (FAO Nutrition Meetings Report Series 46a) TITANIUM DIOXIDE (JECFA Evaluation)