Food Safety: Importance of Composition for Assessing Genetically Modified Cassava (Manihot esculenta Crantz)

Jansen van Rijssen FW, Morris EJ, Eloff JN

Task Force #12

Journal of Agricultural and Food Chemistry. 2013;61(35):8333-8339

Abstract: The importance of food composition in safety assessments of genetically modified (GM) food is described for cassava (Manihot esculenta Crantz) that naturally contains significantly high levels of cyanogenic glycoside (CG) toxicants in roots and leaves. The assessment of the safety of GM cassava would logically require comparison with a non-GM crop with a proven “history of safe use”. This study investigates this statement for cassava. A non-GM comparator that qualifies would be a processed product with CG level below the approved maximum level in food and that also satisfies a “worst case” of total dietary consumption. Although acute and chronic toxicity benchmark CG values for humans have been determined, intake data are scarce. Therefore, the non-GM cassava comparator is defined on the “best available knowledge”. We consider nutritional values for cassava and conclude that CG residues in food should be a priority topic for research.

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