Color Additives Safety, Part 2

by Food and Drug Administration (FDA)

(Page 2 of 4)

Each color has chemical "specifications" that place restrictions on the levels of impurities allowed in the additive. In some cases, these limitations are designed to ensure that the color contains no cancer-causing substances. Using chromatography and other sophisticated analytical techniques, FDA scientists probe sample compositions to confirm that each batch is within these limitations.

"We analyze every batch because every batch is a little different from the one before it," says Bailey. He explains that complex organic chemical reactions occurring during manufacturing can throw off a sample's composition. It's like baking a cake: Even though you follow a recipe closely, the cake turns out just a little different each time.

With certifiable colors, a shift in composition can mean rejection of an entire batch. In fiscal year 1992, of 3,943 batches tested, the agency rejected 40. FDA also regularly inspects color manufacturers and end users such as candy makers.

FDA is especially vigilant in monitoring products from foreign countries, which may contain color additives that are illegal domestically. The agency regularly seizes entire product shipments that contain prohibited colors. Often, this detective work comes easily. FDA, through its "import alerts," flags certain products. "You look for a pattern," says Bailey.

The batch certification program supports itself because the law requires manufacturers to pay FDA a user fee for every pound of color the agency certifies. "We like to think of batch certification as a government success story," Bailey says.

The Red Scare

In 1960, amendments to the Food, Drug, and Cosmetic Act of 1938 added the so-called Delaney anti-cancer clause to FDA's legal mandate. Among other things, the clause prohibits marketing any color additive the agency has found to cause cancer in animals or humans, regardless of amount.

In recent years, regulators have faced a dilemma in light of technological advances that enable scientists to identify smaller and smaller concentrations of a substance and conduct more sensitive toxicological tests. Are such tiny amounts a health threat? Scientists have yet to answer this question. Congress has held hearings to examine the pros and cons of liberalizing the Delaney clause. At press time, debates on the issue were in progress.

FDA applied the Delaney clause in 1990 when it outlawed several uses of the strawberry-toned FD&C Red No. 3. The banned uses include cosmetics and externally applied drugs, as well as uses of the color's non-water-soluble "lake." FDA previously had allowed these "provisional" uses while studies were in progress to evaluate the color's safety. Research later showed large amounts of the color causes thyroid tumors in male rats.

Though FDA viewed Red No. 3 cancer risks as small — about 1 in 100,000 over a 70-year lifetime — the agency banned provisional listings because of Delaney directives. At the same time, Red No. 3 has "permanent" listings for food and drug uses that are still allowed although the agency has announced plans to propose revoking these uses as well. For now, Red No. 3 can be used in foods and oral medications. Products such as maraschino cherries, bubble gum, baked goods, and all sorts of snack foods and candy may contain Red No. 3.

According to the International Association of Color Manufacturers, Red No. 3 is widely used in industry and hard to replace. It makes a very close match for primary red, which is important in creating color blends. It doesn't bleed, so drug companies use it to color pills with discernible shades for identification.

If Red No. 3 joins the ranks of colors forbidden for all uses, it won't be the first FD&C Red in recent years to be pulled from the market. FDA banned FD&C Red No. 2, a tint that continues to be an enigma, in 1976.

In the early 1970s, data from Russian studies raised questions about Red No. 2's safety. Several subsequent studies showed no hazards. FDA conducted its own tests, which were inconclusive. The consumer-oriented Health Research Group petitioned FDA to ban the color, while congressional and public interest mounted.

FDA turned the matter over to its Toxicology Advisory Committee, which evaluated numerous reports and decided there was no evidence of a hazard. The committee then asked FDA to conduct follow-up analyses. Agency scientists evaluated biological data and concluded that "it appears that feeding FD&C Red No. 2 at a high dosage results in a statistically significant increase" in malignant tumors in female rats.

There still was no positive proof of either potential danger or safety. FDA ultimately decided to ban the color because it had not been shown to be safe. The agency based its decision in part on the presumption that the color might cause cancer.

The judgment had a profound effect on consumer attitudes toward certifiable colors, says FDA's John E. Bailey. "The Red No. 2 decision will always be with us, he says. For example, some candy manufacturers reacted by removing red-colored pieces from their products, even if there was no Red No. 2 present. They were afraid sales would plummet because of public perception that red candies were dangerous.

About the Author

www.fda.gov
FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.