<p style="text-align: justify;"><b>Dietary Exposure</b></p>

<p style="text-align: justify;">In the United States and Canada, the primary form of consumption for field maize is as maize-based food ingredients with little whole kernel or processed field maize directly consumed by comparison. Field maize is used as a raw material for the manufacture of starch, which is in turn converted to a variety of sweeteners (such as high fructose maize syrup) and fermentation products (ethanol). The germ of the maize kernel is also used for the production of maize oil. These materials are commonly found in many foods, resulting in wide population dietary exposure to all maize products. The human food uses of grain from MON 863 are not expected to be different from the uses of non-transgenic field maize varieties and therefore the dietary exposure of the general population to MON 863 grain should not be different from that of other field maize varieties.</p>

<p style="text-align: justify;"><b>Nutritional Data</b></p>

<p style="text-align: justify;">Compositional analyses were conducted on plant material (forage and grain) obtained from MON 863 and non-transgenic parental control plants grown at four replicated field trial sites in the United States. As a further comparison, similar analyses were conducted on plant material derived from nine different non-transgenic commercial maize hybrids grown under field conditions at two replicated sites.</p>

<p style="text-align: justify;">Grain samples were analyzed for levels of protein, fat, ash, moisture, carbohydrates, acid detergent fibre (ADF), neutral detergent fibre (NDF), amino acids, fatty acids, vitamin E, minerals [calcium, copper, iron, magnesium (Mg), manganese (Mn), phosphorus (P), potassium, sodium, and zinc (Zn)], phytic acid, and trypsin inhibitor. Other than for the exceptions noted below, there were no statistical difference in the measured values for each of these parameters between MON 863 and the non-transgenic control line, and in each case the values obtained from both were within the range of values for the nine control varieties and those reported in the literature. The exceptions noted were:</p>

<ol>
	<li style="text-align: justify;">Carbohydrate levels and levels of the non-essential amino acids cysteine, aspartic acid, and glycine were higher in MON 863 than in the non-transgenic parental control, but were within the range of values measured for the nine commercial varieties.</li>
	<li style="text-align: justify;">Levels of protein, the essential amino acids leucine and phenylalanine, and the non-essential amino acid glutamic acid, were lower in MON 863 than in the non-transgenic parental control, yet were within the range of values measured for the nine commercial varieties.</li>
	<li style="text-align: justify;">The levels of P, Mg, Zn, Mn, and vitamin E were lower in MON 863 than in the non-transgenic parental control, but were within the range measured for the nine commercial varieties and those reported in the scientific literature.</li>
	<li style="text-align: justify;">The level of phytic acid (a phosphorus-binding dietary antinutrient) was lower in MON 863 than in the non-transgenic parental control, but within the range of values measured for the nine commercial varieties.</li>
</ol>

<p style="text-align: justify;">&nbsp;</p>

<p style="text-align: justify;">Data on levels of protein, fat, ash, moisture, carbohydrates, ADF, and NDF, obtained from forage samples did not reveal any significant differences between MON 863 and the non-transgenic parental control, and all values fell within the range measured for the nine commercial varieties</p>

<p style="text-align: justify;"><b>Toxicity</b></p>

<p style="text-align: justify;">Cry3Bb1 protein extracted and purified from a heterologous <i>E. coli</i> fermentation system was used as the test material for an acute oral toxicity study with mice. The identical <i>cry3Bb1</i> coding sequence used in the transformation of event MON 863 was used in the transformation of <i>E. coli</i>. The protein expressed by <i>E. coli</i> was assessed and found to be physicochemically and functionally equivalent to that expressed in plant tissue. The bacteria expression platform was used since a sufficient amount of the protein could not be purified from plant tissue. In the acute gavage study, the No Observed Adverse Effect Level (NOAEL) was found to exceed 3200 mg/kg the maximum dose achievable. At that level, no mortality or grossly observable adverse effects were noted.</p>

<p style="text-align: justify;">The NOAEL was considered to be four orders of magnitude (5.8 X 104) times greater than the expected human intake of Cry3Bb1 protein from MON 863 maize. The NOAEL was 1000 times greater than the expected livestock dietary intake of Cry3Bb1 protein from MON 863 maize.</p>

<p style="text-align: justify;">The sequence of amino acids making Cry3Bb1 protein was compared to that of known toxins. There was no sequence homology noted with toxins. As well, there were no structural similarities noted between Cry3Bb1 and known toxins.<br />
These factors indicated that Cry3Bb1 had a low probability to exhibit toxicity to humans or livestock consuming MON 863 maize or products derived from it.</p>

<p style="text-align: justify;"><b>Allergenicity</b></p>

<p style="text-align: justify;">Current scientific knowledge indicates that many food allergens tend to be abundant proteins within the food product, resistant to proteolytic digestion and heat inactivation and are often glycosylated. The Cry3b1 protein was assessed for allergenicity by examining its digestibility; amino acid sequence homology to known allergens; its glycosylation profile; and history of safe use of microbial sprays.</p>

<p style="text-align: justify;">The results of an <i>in vitro</i> digestive fate study using simulated gastric fluid (SGF) indicated that Cry3Bb1 protein degraded to nondetectable levels in 15 seconds. The protein is also quickly deactivated upon exposure to heat. The protein was compared to known allergens and did not exhibit amino acid sequence homology. The Cry3Bb1 protein is not glycosylated. As well, the protein is present only at very low levels in edible portions of maize.</p>

<p style="text-align: justify;">The long history of use of <i>Bt</i> toxins in microbial sprays has produced numerous safety studies which have demonstrated its low mammalian toxicity. As well, there have been no confirmed cases of allergic reactions to Cry proteins in scientific literature.</p>

<p style="text-align: justify;">From these collective data it was judged that Cry3Bb1 protein in MON 863 maize was unlikely to be a human allergen.</p>
