Study finds mercury in HFCS, findings questioned

A pair of recent studies found mercury contamination in high-fructose corn syrup and products containing the sweetener, USA Today reported Tuesday, but several groups question the studies’ relevance.

The studies, performed by the Institute for Agriculture and Trade Policy found detectable mercury levels in nine of 20 commercial sources of high-fructose corn syrup, and in nearly a third of 55 brand-name foods. The toxic heavy metal appeared most commonly in dairy products, dressings and condiments that contain HFCS.

USA Today reported that the source of the contamination is a reagent called caustic soda – used to produce HFCS – that is sometimes contaminated with mercury when produced through a specific process. Dr. David Wallinga, co-author of both studies, told the paper that mercury-free HFCS ingredients exist, and food companies need to push suppliers to use only those ingredients.

“Given how much high-fructose corn syrup is consumed by children, it could be a significant additional source of mercury never before considered,” Wallinga told USA Today. “We are calling for immediate changes by industry and the (U.S. Food and Drug Administration) to help stop this avoidable mercury contamination of the food supply.”

The Corn Refiners Association did not immediately return a call for comment, but issued a written statement challenging the studies’ relevance and accuracy. The statement said the industry uses mercury-free reagents, but stopped short of a blanket statement that no corn millers use caustic soda with detectable levels of mercury.

The Chlorine Institute issued its own statement that said food-grade caustic soda must abide by a maximum mercury content defined by the international food safety standards in the Food Chemicals Codex – 0.1 mg per kg, according to Scott Jensen, a spokesman for the American Chemistry Council. That’s one part per 10 million. The Food and Drug Administration pegs safe mercury exposure in fish at one part per million. Jensen added that the standard only applies to plants that use mercury cell technology to produce caustic soda, “And only about 6 percent of caustic soda is made using mercury cell technology.”

That number is down from 12 percent in 2005, when the data used in the studies was gathered, he added.

Additionally, Carl Winter, director of the FoodSafe program at the University of California, Davis, told WebMD that the mercury detected in the study was likely elemental mercury, which is less toxic than methylmercury.

“Frankly,” Winter said, “I don’t see based on their findings that they’ve made much of a case that this is something that consumers need to worry about.”