Mercury confusion

What’s being done about mercury in our food?

In my January 14 column on Alzheimer's disease, I made a passing comment that high-fructose corn syrup is often contaminated with mercury as a result of mercury-grade caustic soda used in its production.

The Corn Refiners Association (CRA) was quick to get in touch with Vue Weekly, respectfully requesting the removal of the “false claim that high fructose corn syrup contains mercury.” They say that “no mercury or mercury-based technology is used in the production of high fructose corn syrup in North America.”

Excellent. But it certainly has been used in the past. And it is still being used in food processing in general. And we really have no way of being certain that it is no longer being used in the production of high-fructose corn syrup (HFCS), short of taking the CRA's word for it.
To clarify and update: mercury cell technology—not limited to HFCS production—is in the process of being phased out. But, as Simon Mahan of the international ocean conservation organization Oceana explained in an email, four US plants still use mercury-cell technology, three of which make caustic soda which may be sold to the food industry. These factories have until 2012 to decide if they would like to modernize to mercury-free technology or shut down.

Further, although old technology is being phased out, there are no restrictions on importing mercury-grade caustic soda. And while imports have gone up, the consumer has no way of knowing which of their foods have been processed with mercury-grade caustic soda, whether from outdated domestic factories or imported.

My comment about HFCS was based on two studies published in January of 2009. The first was a study led by former FDA environmental health researcher Renee Dufault and published in Environmental Health, which found mercury in nearly half of HFCS samples collected in 2005. The other was conducted by David Walinga and the Institute for Agriculture and Trade Policy. It found mercury in nearly a third of HFCS-containing products its researchers took from supermarket shelves for testing.

The CRA’s statement that no mercury-based technology is used in the production of HFCS is based on research conducted by Dr. Stopford, who, according to a CRA press release, was commissioned by their association to do the research. It wasn’t, according to Dufault, peer reviewed. “We can only assume the samples were collected from plants not using mercury grade chlor-alkali,” she told me in a phone interview. 

“The issue is really that mercury-cell products are currently being used in all kinds of food processing,” says Dufault. “Current standards permit the use of mercury cell chlor-alkali chemicals in food manufacturing. There are no restrictions on importing mercury-grade caustic soda.”
Why does the food industry use mercury-grade caustic soda in the first place? “For food production, they prefer mercury-grade because it confers longer product shelf-life,” says Dufault. Mercury is an anti-microbial. It is also a potent neurotoxin.

In October 2009, in Behavioral and Brain Functions, Dufault published another paper on the role of toxic and dietary factors in neurodevelopmental disorders such as autism and mental retardation. Her team found that the peak years for annual consumption of HFCS, which occurred between 2000 and 2002, coincided with the peak for autism.

Despite nearly 5000 downloads online, the paper has received little media coverage.

Dufault's paper states that mercury intake leads to zinc, selenium and other mineral losses alongside the toxic mercury increases, resulting in reduced neuronal plasticity and learning capacity. Learning, behavioural and developmental disorders are an epidemic. Children with Autism Spectrum Disorders have increased body burdens of mercury.

“The American Academy of Pediatrics has issued a strong statement saying that children shouldn't be exposed to any form of mercury,” says Dufault. “But it's everywhere in our food supply. A long list of additives linked to ADHD and learning disabilities can be contaminated. Food colors, sodium benzoate, you name it. Humans are bioaccumulating mercury.”

The Learning and Developmental Disabilities Initiative (LLDI) knows the importance of the issue. Dufault summarizes for me: “They have issued a consensus statement that basically says learning disabilities are linked to a number of factors, factors that include thimerosal, PCBs, nutrition, diet, and genetics. Mercury in all its forms is probably the biggest stressor.”

The Institute for Agriculture and Trade Policy has recommended a complete ban on the use of mercury-grade ingredients in food and beverages. While we're waiting on that to happen (and we could be waiting for some time), their recommendation for consumers is to “avoid foods containing HFCS, particularly when it’s high on the label.”

The FDA has known about mercury contamination since 2005. Dufault was told she should drop the issue and that they’d look into it, but it appears little has been done. The agency's view was that the evidence is insufficient to conclude appreciable risk from potential mercury exposure in food.

The point is that although it isn't just the corn-refining industry, and that although old technology is being phased out, mercury-grade caustic soda is still being imported and widely used in the food processing industry in general.

“When will we stop this?” asks Dufault, “when one in ten of us have some kind of neurological disability?” V

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