Mercury in corn syrup
The presence of mercury in corn syrup was a health controversy that arose due to several studies that found that mercury residues in high-fructose corn syrups used in food products. This was significant due to the toxic nature of mercury and its association with learning disabilities and heart disease.
History of analyses
Three separate studies between 2009-2010 found mercury in high fructose corn syrup or food products containing high fructose corn syrup. The first major study was led by United States Food and Drug Administration (FDA) whistleblower Renee Dufault, who began her research while serving as an Environmental Health Officer (EHO) at the FDA in 2004. Dufault left the agency to publish her findings, which were made public a year after she left the FDA. High fructose corn syrup samples were collected by an FDA field investigator without warning from three separate corn refiners during the week of February 17-24, 2005. Of the twenty samples analyzed, mercury residues were found in nine and the results of the study were published in the peer reviewed journal Environmental Health in 2009.
In a follow-up study led by David Wallinga at the Institute for Agriculture and Trade Policy (IATP), fifty-five foods with HFCS listed as the first or second ingredient, were analyzed for mercury. Of the fifty-five products, mercury was detected in seventeen samples and the results were published in an institutional report in January 2009.
The third study was led by Karen Rideout at the National Collaborating Centre for Environmental Health in Canada in 2010. Rideout's team collected nine Canadian national brand syrup products containing HFCS as the first or second ingredient from major chain grocery stores in Vancouver. All of the samples collected by Rideout's team were analyzed for mercury and concentrations ranged from 0.220 -1.92 ug/l.The results were peer-reviewed and published as a comment on the article published by Dufault and her collaborators in Environmental Health in 2010, a year after the Corn Refiners Association had claimed that there were no quantifiable levels of mercury in high-fructose corn syrup manufactured in US and Canada production facilities.