Among the myriad stories on food safety and health facing consumers is a surprising wave of media coverage of a lawsuit filed by a California resident regarding very slight amounts of titanium dioxide used as a colorant in the popular Mars candy, Skittles.

According to the National Library of Medicine, titanium dioxide is a naturally occurring oxide that is sourced from ilmenite, rutile, and anatase. The class-action lawsuit claims that titanium dioxide is a “known toxin” and “unfit for human consumption.” It has been banned in the European Union as a food additive.

In the United States, Canada, and Britain, titanium dioxide is used in several products including toothpaste, sunscreen, and paint, and food items such as candy and chewing gum, baked goods, dressings, sandwich spreads, ice cream, coffee creamers, and cottage cheese.

Its properties include whitening and brightening, so for a candy like Skittles, it is what makes the colors so bright. But is titanium dioxide a “known toxin?”

As far back as 1979, the National Cancer Institute (NCI) of the U.S. National Institutes of Health determined that the substance is not carcinogenic. This conclusion was reached after a substantial amount of titanium dioxide was given to rats and mice in their food consistently over a period of two years. No tumors were found in the rats and “…in male and female mice, no tumors occurred in dosed groups at incidences that were significantly higher than those for corresponding control groups.”

More recent animal studies have suggested possible toxicity (in the form of the development of abnormal glands that are a precursor to colon cancer) when titanium dioxide is given to rats in water, but these studies have been criticized for not administering the chemical in food the way humans consume it, and for not having enough control over dosage.

On the other hand, the International Agency for Research on Cancer (IARC) determined it is possibly carcinogenic in humans.

The European Food Safety Authority has taken the position that because there is not yet conclusive research on whether titanium dioxide is safe for humans at very low doses as a food additive, they would rather err on the side of caution and ban it. They tend to follow the precautionary principle. This principle, in short, refers to not waiting for research to conclusively show danger before taking policy action on a particular exposure. It is also part of a European effort to ban all nanoparticles in food.

The United States tends to rely on risk-based decision-making, which waits for the determination of some degree of risk before any policies or management actions are put in place. Since there are no good data showing that titanium dioxide poses a danger to humans, the FDA has determined it should be allowed in very small amounts (the FDA limits it to no more than 1% of the weight of the item to which it is being added).

There are merits and limitations to both approaches. However, the broader questions around this lawsuit are worth examining: In the case of a candy that is not a necessary part of an individual’s (especially a child’s) diet, is this something that needs to be extensively pondered and decided by the courts?

Should the Mars Corporation be found liable when the FDA allows the use of titanium dioxide as a colorant, based on their assessment that it is low risk?

The research on titanium dioxide as a food additive is very available to consumers, parents, and policymakers. The FDA was aware of it when it made the decision to allow its use in the United States in small quantities. It is up to parents and other adults to make decisions about consuming food items that contain it (and after the enormous amount of press coverage this lawsuit has received, many now know Skittles sold in the U.S. contain small amounts of it).

While there is currently no U.S. regulation requiring mention of the use of titanium dioxide on food labels, this is an easy fix. The FDA could make it a requirement on labels in a very short time if they deemed it necessary based on the science.

Meanwhile, as parents examine the label on a bag of Skittles to see if there is anything they don’t want their children to eat, they may glance at the amount of sugar and make an entirely different decision…