anatase tio2 pigment quotes

The National Cancer Institute tested TiO2 for possible carcinogenicity by the oral route of exposure by feeding rats and mice with TiO2 (size not specified) at doses 25,000 or 50,000 ppm TiO2 for 103 weeks. They concluded that TiO2 was not carcinogenic.Also, the study with rats fed diets containing up to 5 % TiO2 coated mica for 130 weeks showed no treatment-related carcinogenicity. Since the size and other TiO2 properties were not specified or determined, we cannot generalize this conclusion and we have to take into account other possible outcomes of this scenario in different exposure conditions (other size/crystalline structure of TiO2 etc.).

...
...

This article discusses the discovery of phosphorescent lithopone on watercolor drawings by American artist John La Farge dated between 1890 and 1905 and the history of lithopone in the pigment industry in the late 19th and early 20th centuries. Despite having many desirable qualities for use in white watercolor or oil paints, the development of lithopone as an artists’ pigment was hampered by its tendency to darken in sunlight. Its availability to, and adoption by, artists remain unclear, as colormen's trade catalogs were generally not explicit in describing white pigments as containing lithopone. Further, lithopone may be mistaken for lead white during visual examination and its short-lived phosphorescence can be easily missed by the uninformed observer. Phosphorescent lithopone has been documented on only one other work-to-date: a watercolor by Van Gogh. In addition to the history of lithopone's manufacture, the article details the mechanism for its phosphorescence and its identification aided by Raman spectroscopy and spectrofluorimetry.

...