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.

Relative to a lot of other things that people should be concerned about, titanium dioxide in my mind, is really low on the list. I would be more worried about some substitutes that people are using for titanium dioxide that don't have decades of research associated with it, said Westerhoff.

While Skittles don't include white in their line-up, Dr. Johnson-Arbor theorizes that titanium dioxide is used to help contain all the other beautiful colors.

In response to the allegations, Justin Comes, vice president of research and development at Mars Wrigley North America, told Health that safety is of paramount importance to Mars Wrigley. While we do not comment on pending litigation, all Mars Wrigley ingredients are safe and manufactured in compliance with strict quality and safety requirements established by food safety regulators, including the FDA.

Lithopone Market