Researchers in the US found that much of the high fructose corn syrup that is increasingly replacing sugar in processed foods is tainted with mercury, a metal that is toxic to humans. They also tested many branded food products and found they too contained mercury.

The findings come from two studies, one of which is published in the journal Environmental Health and the other is by the Institute for Agriculture and Trade Policy (IATP). Dr David Wallinga, who works at the IATP, was involved in both studies. He told the press that mercury was toxic in all its forms, and that:

“Given how much high fructose corn syrup is consumed by children, it could be a significant additional source of mercury never before considered.”

“We are calling for immediate changes by industry and the FDA [Food and Drug Administration] to help stop this avoidable mercury contamination of the food supply,” said Wallinga.

Use of HFCS as a sweetener instead of sugar has risen sharply in recent decades, and now is commonly used to sweeten breads, cereals, breakfast bars, beverages, luncheon meats, yogurts, soups, and condiments. According to IATP estimates, the average American probably eats about 12 teaspoons of HFCS a day, with teenagers and consumers on the higher end of the spectrum perhaps eating 80 per cent higher than this.

In the first Environmental Health study, researchers, led by Renee Dufault, who was working at the FDA at the time, found mercury in nearly 50 per cent (9 out of 20) of samples of commercial high fructose corn syrup (HFCS) they tested in 2005.

They concluded that the food industry, which is a large user of the sweetener, was mostly ignorant of the possibility that ingredients like HFCS could be tainted with mercury. According to an IATP press release, although the FDA had “evidence that commercial HFCS was contaminated with mercury four years ago”, the federal agency “did not inform consumers, help change industry practice or conduct additional testing”.

In the second, IATP study, researchers sent 55 popular branded foods and drinks where HFCS is the first or second highest labelled ingredient to a commercial laboratory for testing; they found that nearly one third of them contained trace amounts of mercury. The brands included those made by Quaker, Hershey’s, Kraft and Smucker’s, big names in the US. The mercury was most prevalent in dairy products containing HFCS, followed by dressings and condiments that contained the sweetener.

How does the mercury get into the corn syrup?

For decades, HFCS has been made using mercury-grade caustic soda produced in so-called “chlor-alkali” or industrial chlorine plants that use mercury cells. The caustic soda, which can thus contain traces of mercury, is used to separate the corn starch (that goes to make the syrup) from the kernel.

Wallinga said:

“The bad news is that nobody knows whether or not their soda or snack food contains HFCS made from ingredients like caustic soda contaminated with mercury.”

“The good news is that mercury-free HFCS ingredients exist. Food companies just need a good push to only use those ingredients,” he added.

More modern chlorine plants already use cleaner technologies that don’t use mercury cells, but there are many older ones still around that do, said the researchers.

In 2005, although 90 per cent of chlorine production did not involve mercury, only 40 per cent of that produced in Europe was mercury-free.

The IATP said there are still four of the older chlor-alkali plants that use mercury cells in the US. In 2007, then Senator Barack Obama brought in legislation to make these plants phase out mercury cell technology by 2012.

“Mercury from chlor-alkali plants: measured concentrations in food product sugar.”
Renee Dufault, Blaise LeBlanc, Roseanne Schnoll, Charles Cornett, Laura Schweitzer, Lyn Patrick, Jane Hightower, David Wallinga, Walter Lukiw.
Environmental Health 2009, 8:2 (26 January 2009).

Click here for Abstract.

“Not So Sweet: Missing Mercury and High Fructose Corn Syrup.”
David Wallinga, Janelle Sorensen, Pooja Mottl and Brian Yablon.
Institute for Agriculture and Trade Policy (IATP), 26 January 2009.

Click here for PDF download of article.

Click here for PDF download of table showing the 55 branded products and the levels of mercury detected (IATP).

Sources: Institute for Agriculture and Trade Policy.

Written by: Catharine Paddock, PhD