There are two primary forms of titanium dioxide commercially available: anatase and rutile. The rutile form is typically used in sunscreens due to its superior ability to handle UV rays and stability in the presence of UV light. The anatase form is typically used in other types of products, such as paint. Another plus of the rutile form is that its UVA protection extends past 400 nanometers, which is the upper limit of UVA.

6. What happens next?

It’s produced through the sulfate or chloride process, which both involve treating titanium ore with sulfuric or hydrochloric acid to produce titanium sulfate or titanium chloride. These materials are then further processed to remove impurities and produce titanium dioxide in its final form.

Still, in 2016 Skittles publicly declared it would get rid of the chemical compound in its products, according to a press release at the time from the Center for Food Safety, which called the substance harmful and potentially poisonous. But the ingredient remains, according to the lawsuit, which alleges the candy company is misleading consumers by not having eliminated titanium dioxide.

When asked about the recent Skittles lawsuit, the FDA said the agency does not comment on pending litigation.