Solvent Impurity Rule Leaves Carcinogen Questions Open in Food Dye Production

The FDA is revoking authorization for three solvents used to make natural color additives, but the reasoning behind the move is drawing sharp criticism. Consumer advocates argue that a technical classification is doing the work that a cancer finding should be doing.

The agency will no longer allow methylene chloride, ethylene dichloride, and trichloroethylene in producing annatto extract, paprika oleoresin, and turmeric oleoresin. Those are colorants that many buyers see as the natural alternative to synthetic dyes. The revocations take effect Jan. 11.

A fourth action sits apart from the color additive question. Methylene chloride, the solvent found in paint strippers, loses its authorization for use in inks that mark fruits and vegetables. The FDA cited evidence that the substance causes cancer in humans or animals.

Abandonment is doing the heavy lifting

The agency's main justification for the solvent revocations is simple: the food industry has mostly stopped using these chemicals in food dyes. The FDA says it confirmed that abandonment, and that's the basis on which it moved.

Here's the thing: abandonment is a practical reason, not a health one. Removing a chemical nobody uses carries little cost, and it's an easy win. The harder question is what happens when the chemical is still in use.

That's where the impurity argument comes in. The Environmental Defense Fund petitioned the FDA to ban the solvents outright on cancer grounds. The agency denied that request. Its position is that the solvents are impurities in color additives, not color additives themselves.

That distinction carries weight. The Delaney clause, a provision of a 1958 law that set up modern food additive regulation, bars approval of any color additive found to cause cancer. The FDA used that clause to revoke Red No. 3 last year. In the ink case, the agency cited Delaney. In the dye production case, it didn't, because it treats the solvent as an impurity and the clause doesn't reach it.

Where the pushback lands

The EDF argues the classification sidesteps the purpose of the law. "Classifying these cancer-causing chemicals as 'impurities' does not eliminate their potential to harm people," the group said in a statement. It warned that if the reasoning carries into future decisions, "Americans [will be] exposed to cancer causing chemicals in their food."

Maria Doa, senior director of chemicals policy at the EDF, put it more bluntly. "The FDA must put consumer health ahead of industry interests to faithfully implement the Delaney Clause, which prohibits the use of cancer-causing ingredients in food," she said. "This means continuing to eliminate all uses of carcinogens still permitted in our food supply, regardless of industry buy-in."

The methylene chloride story has another open thread. The FDA hasn't yet acted on a related petition to remove other uses of the solvent, including in decaffeinating coffee. Earlier this year, a federal court threw out EPA restrictions that banned most uses of methylene chloride, finding the agency had gone too far with its prohibitions. That ruling makes the coffee question harder to predict.

A pattern worth watching

The dye actions fit a broader approach. Consumer concern about artificial colors has become a central piece of the Make America Healthy Again agenda, but much of that push has depended on voluntary industry moves. Where the FDA has acted, it has mostly targeted outdated chemicals. Earlier this year, it revoked Orange B and Citrus Red No. 2, which it said the industry had largely abandoned. Health and Human Services Secretary Robert F. Kennedy Jr. framed that step as part of efforts to eliminate "outdated authorizations for petroleum-based color additives that are no longer used."

My read is that the solvent decision will be judged less by its immediate scope than by what it signals. If an impurity classification becomes the standard route for chemicals with documented cancer concerns, the Delaney clause will have less practical reach than its text suggests. The decaffeinated coffee petition is the next test of whether that's the agency's intent.