<p style="text-align: justify;">Maize, or corn (<i>Zea mays</i> L.) is grown primarily for its kernel, which is largely refined into products used in a wide range of food, medical, and industrial goods. Maize is a raw material for the manufacture of starch, the majority of which is converted by a complex refining process into sweeteners, syrups and fermentation products, including ethanol. Maize oil is extracted from the germ of the maize kernel. Only a small proportion of the whole kernel is consumed by humans, while refined maize products, sweeteners, starch, and oil are abundant in processed foods such as breakfast cereals, dairy goods, and chewing gum. In the United States and Canada, maize is typically used as animal feed with roughly 70% of the crop fed to livestock, although an increasing amount is being used for the production of ethanol. The entire maize plant, kernels, and several refined products such as glutens and steep liquor, are used in animal feeds. Silage made from the whole maize plant makes up 10-12% of the annual corn acreage, and is a major ruminant feedstuff. Livestock that feed on maize include cattle, pigs, poultry, sheep and goats, fish and companion animals. Industrial uses for maize products include recycled paper, paints, cosmetics and car parts. Refined maize products are also used in bioproducts such as antibiotics. The European corn borer (ECB),<i> Ostrinia nubilalis</i>, is the most damaging insect pest of maize in the United States and Canada with losses resulting from ECB damage and control costs exceeding $1 billion each year. An average of one ECB cavity per maize stalk across an entire field can reduce yield by as much as 5% when caused by first generation larvae, and 2.5% when caused by second generation larvae, with annual yield losses estimated at 5 to 10 %. Despite consistent losses to ECB, chemical insecticides are utilized on a relatively small acreage (less than 20%). Historically, this reluctance stems from the difficulties in managing ECB in maize crops: ECB larval damage is hidden; heavy infestations are unpredictable; insecticides are costly; timing of insecticide application is difficult and multiple applications may be required to guarantee ECB control. The transgenic maize line MON810 was genetically engineered to resist ECB by producing its own insecticide. This line was developed by introducing the <i>cry1Ab</i> gene, isolated from the common soil bacterium <i>Bacillus thuringiensis</i> (<i>Bt</i>), into the maize cultivar Hi-II by particle acceleration (biolistic) transformation. The <i>cry1Ab</i> gene produces the insect control protein Cry1Ab, a delta-endotoxin. MON810 expressed Cry1Ab at an effective dosage over the growing season as indicated by its efficacy in controlling both first and second generation infestations of ECB, however, protein expression declined over the growing season as indicated by declining Cry1Ab protein concentrations in assayed leaves. The insecticidally active portion of the Cry1Ab protein produced by the <i>Bt</i> maize is identical to that found in nature and in commercial <i>Bt</i> spray formulations. Cry proteins, of which Cry1Ab is only one, act by selectively binding to specific sites localized on the lining of the midgut of susceptible insect species. Following binding, pores are formed that disrupt midgut ion flow causing gut paralysis and eventual death due to bacterial sepsis. Cry1Ab is insecticidal only when eaten by the larvae of lepidopteran insects (moths and butterflies), and its specificity of action is directly attributable to the presence of specific binding sites in the target insects. There are no binding sites for delta-endotoxins of <i>B. thuringiensis</i> on the surface of mammalian intestinal cells, therefore, livestock animals and humans are not susceptible to these proteins. MON810 was tested in field trials in the United States and Canada. Data collected from these trials demonstrated that MON810 was not different from conventional maize varieties. MON810 grew normally and exhibited the expected morphology, reproductive and physiological characteristics of maize. Furthermore, MON810 was shown not to have unexpected pest or disease susceptibility compared to conventional maize. Maize does not have any closely related species growing in the wild in continental United States and Canada. Cultivated maize can naturally cross with annual teosinte (<i>Zea mays</i> ssp. mexicana) when grown in close proximity, however, these wild maize relatives are native to Central America and are not naturalized in Canada or the United States. Additionally, reproductive characteristics such as pollen production, viability, and dispersal were unchanged in MON810. Gene exchange between MON810 and maize relatives was determined to be negligible in managed ecosystems, with no potential for transfer to wild species in Canada and the United States. Maize inbreds and hybrids expressing the Cry1Ab protein were compared to their non-transformed counterpart for relative abundance of beneficial arthropods. Field studies demonstrated that Cry1Ab had neither a direct nor an indirect effect on the beneficial arthropod populations. In summary, it was determined that when compared with currently commercialized maize varieties, MON810 maize did not present an increased risk to or impact on interacting organisms, including humans, with the exception of specific lepidopteran insect species. Regulatory authorities in Canada and United States have mandatory requirements for developers of <i>Bt</i> maize to implement specific Insect Resistant Management (IRM) Programs. The potential exists for <i>Bt</i>-resistant ECB populations to develop as acreages planted with transgenic <i>Bt</i> hybrids expand. Hence, these IRM programs are designed to reduce this potential and prolong the effectiveness of plant-expressed <i>Bt</i> toxins, and the microbial <i>Bt</i> spray formulations that contain these same toxins. The food and livestock feed safety of MON810 maize was established based on several standard criteria. As part of the safety assessment, the nutritional composition of MON810 grain was found to be equivalent to conventional maize as shown by the analyses of key nutrients including proximates (<i>e.g.</i> moisture, protein, fat, fibre, ash and carbohydrate), amino acid composition, fatty acid profiles, and minerals (calcium and phosphorus). Similar compositional analyses were conducted on MON810 green chop silage forage. The nutritional equivalence of MON810 and conventional maize was confirmed in feeding trials with bobwhite quail. The low potential for toxicity of plant-expressed Cry1Ab protein was demonstrated by the lack of amino acid sequence homology with known protein toxins and by laboratory studies showing that the protein was rapidly degraded in simulated gastric fluids and that it did not display any acute toxicity when administered to laboratory mice. In the latter study, mice were fed high doses of Cry1Ab protein that were 200-1000 fold greater than humans would be exposed to based on consumption of MON810 grain with no negative consequences. The potential allergenicity of Cry1Ab was assessed by examining: physiochemical characteristics; amino acid sequence homology to known protein allergens; and digestibility. The Cry1Ab protein has a history of safe use, demonstrated by its use in microbial <i>Bt</i> spray formulations in agriculture and forestry for more than 30 years with no evidence of adverse effects. This fact, combined with the lack of amino acid sequence homology between Cry1Ab protein and known allergens, and the rapid degradation of Cry1Ab protein in acidic gastric fluids, were sufficient to provide with reasonable certainty that Cry1Ab has no allergenic potential.</p>

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