Decision Document 2012-91: Determination of the Safety of Bayer CropScience Inc.'s Soybean (Glycine max (L.) Merr.) Event FG72

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This Decision Document has been prepared to explain the regulatory decision reached under Directive 94-08 (Dir 94-08) – Assessment Criteria for Determining Environmental Safety of Plants with Novel Traits, its companion document BIO1996-10 – The Biology of Glycine max (L.) Merr. (Soybean), and Chapter 2.6 of the Regulatory Guidance: Feed Registration Procedures and Labelling Standards – Guidelines for the Assessment of Novel Feeds: Plant Sources.

The Canadian Food Inspection Agency (CFIA), specifically the Plant Biosafety Office of the Plant Health and Biosecurity Directorate, the Plant and Biotechnology Risk Assessment Unit of the Plant Health Science Directorate and the Animal Feed Division of the Animal Health Directorate, has evaluated information submitted by Bayer CropScience Inc. This information is in regard to the herbicide tolerant soybean event FG72. The CFIA has determined that this plant with a novel trait (PNT) does not present altered environmental risk nor, as a novel feed, does it present livestock feed safety concerns when compared to currently commercialized soybean varieties in Canada.

Taking into account these evaluations, unconfined release into the environment and use as livestock feed of soybean event FG72 is therefore authorized by the Plant Biosafety Office of the Plant Health and Biosecurity Directorate and the Animal Feed Division of the Animal Health Directorate as of June 26, 2012. Any soybean lines derived from soybean event FG72 may also be released into the environment and used as livestock feed, provided that

  1. no inter-specific crosses are performed,
  2. the intended uses are similar,
  3. it is known based on characterization that these plants do not display any additional novel traits and are substantially equivalent to currently grown soybean in Canada, in terms of their potential environmental impact and livestock feed safety, and
  4. the novel genes are expressed at a level similar to that of the authorized line.

Additionally, with respect to its use as livestock feed, soybean event FG72 must meet the restrictions specific to isoxaflutole (IFT)-treated forage and hay set out in this authorization.

Soybean event FG72 is subject to the same phytosanitary import requirements as its unmodified counterpart. Soybean event FG72 is required to meet the requirements of other jurisdictions; including but not limited to, the Food & Drugs Act and the Pest Control Products Act.

Please note that the livestock feed and environmental safety assessments of novel feeds and PNTs are critical steps in the potential commercialization of these plant types. Other requirements, such as the evaluation of food safety by Health Canada, have been addressed separately from this review.

This bulletin is published by the Canadian Food Inspection Agency. For further information, please contact the Plant Biosafety Office or the Animal Feed Division at:

Plant Biosafety Office
Plant Health and Biosecurity Directorate
59 Camelot Drive
Ottawa ON K1A 0Y9
613-225-2342
Animal Feed Division
Animal Health Directorate
59 Camelot Drive
Ottawa ON K1A 0Y9
613-225-2342

Table of Contents

  1. Brief Identification of the Modified Plant
  2. Background Information
  3. Description of the Novel Trait
    1. Development Method
    2. Tolerance to Glyphosate
    3. Tolerance to isoxaflutole (IFT)/isoxaflutole-diketonitrile (DKN)
    4. Stable Integration into the Plant Genome
  4. Criteria for the Environmental Assessment
    1. Potential of Soybean Event FG72 to Become a Weed of Agriculture or be Invasive of Natural Habitats
    2. Potential for Gene Flow from Soybean Event FG72 to Sexually Compatible Plants Whose Hybrid Offspring May Become More Weedy or More Invasive
    3. Altered Plant Pest Potential of Soybean Event FG72
    4. Potential Impact of Soybean Event FG72 on Non-Target Organisms
    5. Potential Impact of Soybean Event FG72 on Biodiversity
  5. Criteria for the Livestock Feed Assessment
    1. Potential Impact of Soybean Event FG72 on Livestock Nutrition
    2. Potential Impact of Soybean Event FG72 on Animal Health and Human Safety as it Relates to the Potential Transfer of Residues into Foods of Animal Origin, and Worker/Bystander Exposure to the Feed
  6. New Information Requirements
  7. Regulatory Decision

I. Brief Identification of the Modified Plant

Designation of the Modified Plant: Soybean event FG72, OECD Unique Identifier MST-FGØ72-2
Applicant: Bayer CropScience Inc.
Plant Species: Soybean (Glycine max L.)
Novel Traits: Tolerance to glyphosate and isoxaflutole (IFT)/isoxaflutole-diketonitrile (DKN)
Trait Introduction Method: Biolistic-mediated transformation
Intended Use of the Modified Plant: Human consumption and livestock feed use. Soybean event FG72 is not intended to be grown outside the normal production area for soybeans in Canada.

II. Background Information

Bayer CropScience Inc. and M.S. Technologies LLC have developed a soybean event that is tolerant to the herbicides glyphosate and to the isoxaflutole (IFT) derivative: isoxaflutole-diketonitrile (DKN), a p-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitor. This soybean event, designated FG72, was developed to provide growers with new options for weed control using IFT herbicide in combination with glyphosate herbicide.

The herbicide tolerance traits were introduced by biolistic-mediated transformation, resulting in the introduction of the 2mepsps gene, derived from the maize epsps gene, which confers tolerance to the herbicide glyphosate and the hppdPfW336 gene, derived from the hppd gene of Pseudomonas fluorescens, which confers tolerance to the IFT derivative, DKN. Bayer CropScience Inc. has provided data on the identity of soybean event FG72, a detailed description of the transformation method, data and information on the insertion site, gene copy number and levels of gene expression in the plant and the role of the inserted genes and regulatory sequences. The novel proteins were identified and characterized. Data was provided for the evaluation of the potential toxicity of the novel proteins to humans, livestock and non-target organisms and potential allergenicity of the novel proteins to humans and to livestock. Data were provided for the evaluation of herbicide residues in the feed commodities derived from the crop, following the intended herbicide application.

Soybean event FG72 was field tested in the United States (US) in 10 locations in the 2008 growing season and in 6 locations in the 2009 growing season. The US locations share similar environmental and agronomic conditions to southwestern Ontario and were considered to be representative of major Canadian soybean growing regions.

Agronomic characteristics of soybean event FG72, such as emergence, early stand count, plant vigour, flowering date, plant height, lodging, pod shattering, days to maturity and yield were compared to those of the unmodified control.

Nutritional components of soybean event FG72, such as protein, fat, carbohydrates, fibre, ash, moisture, amino acids, fatty acids, vitamins and anti-nutrients were compared with those of the unmodified control.

The Plant and Biotechnology Risk Assessment (PBRA) Unit of the Plant Health Science Directorate, CFIA, has reviewed the above information, in light of the assessment criteria for determining environmental safety of PNTs, as described in Directive 94-08 (Dir 94-08) – Assessment Criteria for Determining Environmental Safety of Plants with Novel Traits. The PBRA Unit has considered:

  • the potential of soybean event FG72 to become a weed of agriculture or to be invasive of natural habitats;
  • the potential for gene-flow from soybean event FG72 to sexually compatible plants whose hybrid offspring may become more weedy or more invasive;
  • the potential for soybean event FG72 to become a plant pest;
  • the potential impact of soybean event FG72 and its gene products on non-target species, including humans; and
  • the potential impact of soybean event FG72 on biodiversity.

The Animal Feed Division (AFD), of the Animal Health Directorate, CFIA, has also reviewed the above information with respect to the assessment criteria for determining the safety and efficacy of livestock feed, as described in Chapter 2.6 of the Regulatory Guidance: Feed Registration Procedures and Labelling Standards – Guidelines for the Assessment of Novel Feeds: Plant Sources.

The AFD has considered both intended and unintended effects and similarities and differences between the modified plant and its counterpart relative to the safety and efficacy of feed ingredients derived from soybean event FG72 for their intended purpose; including:

  • potential impact of soybean event FG72 on livestock nutrition and
  • potential impact of soybean event FG72 on animal health and human safety as it relates to the potential transfer of residues into foods of animal origin, and worker/bystander exposure to the feed.

The AFD has also considered whether feeds derived from soybean event FG72 meet the definitions and requirements of feeds as listed in Schedule IV. of the Feeds Regulations.

Bayer CropScience Inc. has provided the CFIA with a method for the detection and identification of soybean event FG72.

III. Description of the Novel Trait

1. Development Method

Soybean event FG72 was developed through biolistic-mediated transformation of soybean somatic embryos with a DNA fragment containing the 2mepsps and hppdPfW336 genes plus their regulatory sequences. Transformed cells were selected on the basis of tolerance to an IFT derivative.

2. Tolerance to Glyphosate

The herbicide glyphosate targets the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) enzyme in plants, which is part of the shikimic acid pathway essential for the production of the aromatic amino acids, leading to growth suppression or death of the plant. Soybean event FG72 produces a 2mEPSPS enzyme which contains two amino acids changes, compared to the wild type maize enzyme, making it insensitive to glyphosate such that expression of this enzyme in soybean event FG72 imparts field level tolerance to glyphosate.

The 2mEPSPS enzyme has been subject to previous CFIA safety assessments, such as Bayer CropScience Inc.'s cotton event GHB614 (DD2008-72).

The 2mepsps gene expressed in soybean event FG72 is linked to a constitutive promoter. Samples of soybean event FG72 tissues were collected at various growth stages from greenhouse grown plants in Belgium in 2009. Average 2mEPSPS protein expression levels in micro-grams protein per gram dry weight tissue (µg/g dwt) evaluated by enzyme-linked immunosorbent assay are as follows: 569 µg/g dwt in V4 leaf, 437 µg/g dwt in V6 leaf, 668 µg/g dwt in V8 leaf, 211 µg/g dwt in V4 stem, 117 µg/g dwt in V8 stem, 32.5 µg/g dwt in V4 root, 43.7 µg/g dwt in V8 root and 2.62 µg/g dwt in seed.

To obtain sufficient quantities of 2mEPSPS protein for evaluation of environmental and feed safety, it was necessary to express the 2mepsps gene in a microbial production system. Equivalency was demonstrated between soybean event FG72-produced 2mEPSPS protein and a microbial-produced 2mEPSPS protein that had been used in studies previously submitted for Bayer CropScience Inc.'s cotton event GHB614, and these studies were accepted to support the safety of soybean event FG72. This demonstration of equivalency was based on a comparison of the proteins' molecular weights, immunoreactivities, amino-terminal sequences, matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry profiles and functional activities.

Bayer CropScience Inc. provided a bioinformatics evaluation of the 2mEPSPS amino-acid sequence, which confirmed the lack of relevant similarities between the 2mEPSPS protein and known toxins and allergens. Many allergens have been reported to be expressed at high levels in plants, be resistant to digestive enzymes and heat and be glycosylated. The 2mEPSPS protein was expressed at low levels in soybean event FG72. In vitro digestive fate and heat-stability studies showed that the 2mEPSPS is rapidly degraded in simulated gastric fluid and is not heat-stable.

An acute oral mouse toxicity study of the 2mEPSPS protein previously submitted for Bayer CropScience Inc.'s cotton event GHB614 indicated that the 2mEPSPS protein did not cause any adverse effects in mice following a single oral dose of 2000 mg 2mEPSPS protein/kg body weight. These results indicate that the 2mEPSPS protein in soybean event FG72 is unlikely to be a toxin or allergen.

3. Tolerance to IFT/DKN

HPPD inhibitor herbicides act by inhibiting the p-hydroxyphenylpyruvate dioxygenase enzyme, which leads to bleaching and death in susceptible plants. The herbicide IFT is absorbed by plants where it is converted into the active, diketonitrile form of the herbicide DKN. The DKN directly inhibits the HPPD enzyme pathway. The HPPDW336 enzyme contains a single amino acid change, compared to the wild type Pseudomonas fluorescens enzyme, making it insensitive to DKN. Thus, expression of this enzyme in soybean event FG72 imparts field level tolerance to DKN, from the application of the parent herbicide IFT.

The hppdPfW336 gene expressed in soybean event FG72 is linked to a constitutive promoter. Samples of soybean event FG72 tissues were collected at various growth stages from greenhouse grown plants in Belgium in 2009. Average HPPDW336 protein expression levels in micro-grams protein per gram dry weight tissue (µg/g dwt) evaluated by enzyme-linked immunosorbent assay are as follows: 38.4 µg/g dwt in V4 leaf, 35.8 µg/g dwt in V6 leaf, 27.2 µg/g dwt in V8 leaf, 16.6 µg/g dwt in V4 stem, 6.04 µg/g dwt in V8 stem, 5.81 µg/g dwt in V4 root, 6.42 µg/g dwt in V8 root and 1.41 µg/g dwt in seed.

To obtain sufficient quantities of HPPDW336 protein for evaluation of environmental and feed safety, it was necessary to express the hppdPfW336 gene in a microbial production system. The equivalency of the soybean event FG72-produced HPPDW336 protein to microbial-produced HPPDW336 protein used in safety studies was demonstrated on the basis of combinations of the following: molecular weights, immunoreactivity, N-terminal sequence analysis, MALDI-TOF mass spectrometry and functional activity. Based on the results, the proteins were found to be equivalent.

Bayer CropScience Inc. provided a bioinformatics evaluation of the HPPDW336 amino-acid sequence, which confirmed the lack of relevant similarities between the HPPDW336 protein and known toxins and allergens. Many allergens have been reported to be expressed at high levels in plants, be resistant to digestive enzymes and heat and be glycosylated. The HPPDW336 protein was expressed at low levels in soybean event FG72, in vitro digestive fate and heat-stability studies showed that the HPPDW336 is rapidly degraded in simulated gastric fluid and is not heat-stable. Furthermore, the microbial HPPDW336 protein did not cause any adverse effects in mice following a single oral dose of 970 mg HPPDW336 protein/ kg body weight. These results indicate that the HPPDW336 protein in soybean event FG72 is unlikely to be a toxin or allergen.

4. Stable Integration into the Plant Genome

Molecular characterization by DNA sequencing and Southern blot analysis demonstrated that soybean event FG72 possesses a single insertion site containing two complete copies of both the 2mepsps and hppdPfW336 genes plus their regulatory elements. Partial copies of the inserted DNA and small rearrangements of soybean DNA were also present at the insertion site. These partial insertions and deletions of soybean DNA did not result in unintended open reading frames associated with potential regulatory sequences or displaying homology to known toxins or allergens. No backbone sequences from the plasmid vector, linked or unlinked to the intact insert, were detected in soybean event FG72.

The stability of the insert within soybean event FG72 was verified by Southern blot analysis over different generations, genetic backgrounds and environmental conditions. Inheritance of the herbicide tolerance traits in soybean event FG72 was assessed by measuring tolerance of the plants to the herbicide glyphosate and the presence of the DNA insert by molecular methods. The herbicide tolerance traits were shown to segregate according to Mendelian rules of inheritance for a single genetic locus.

IV. Criteria for the Environmental Assessment

1. Potential of Soybean Event FG72 to Become a Weed of Agriculture or be Invasive of Natural Habitats

The biology of soybean, as described in the CFIA biology BIO1996-10 – The Biology of Glycine max (L.) Merr.. (Soybean), is such that unmodified plants of this species are not invasive of unmanaged habitats in Canada. Soybean does not possess an intrinsic potential to become weedy in Canada due to traits such as the lack of seed dormancy and the poor competitive ability of seedlings. According to the information provided by Bayer CropScience Inc., soybean event FG72 showed no biologically meaningful differences from the unmodified control in this respect.

The CFIA evaluated data submitted by Bayer CropScience Inc. on the reproductive biology and life history traits of soybean event FG72. This event was field tested in the US at 10 locations in the 2008 growing season and at 6 locations in the 2009 growing season. The unmodified control and a range of conventional soybean varieties were also grown in the field trials. The US locations share similar environmental and agronomic conditions to southwestern Ontario and were considered to be representative of major Canadian soybean growing regions. During the field trials, several agronomic characteristics were evaluated including emergence, early stand count, plant vigour, flowering date, plant height, lodging, pod shattering, days to maturity and yield. Although instances of statistically significant differences were observed between soybean event FG72 and the unmodified control for some traits, there were few consistent trends in the data across locations or years that would indicate the differences were due to the genetic modification. For example, there was an indication of a trend occurring in which soybean event FG72 had a lower yield and a shorter plant height than that of the unmodified control. However, the values for soybean event FG72 were within the reference range established for conventional soybean varieties grown in the same field trials for both of these traits. Therefore, the statistical analysis of these observations showed no biologically meaningful differences between soybean event FG72 and the unmodified control, and supports a conclusion of agronomic equivalence to conventional soybean varieties.

Bayer CropScience Inc. provided information on the dormancy and germination of soybean event FG72 seed under a warm and a cool temperature regime. No significant difference was detected for germination at either a warm or a cool temperature between soybean event FG72 and an unmodified control. Although there were occurrences of a low percentage of hard non-germinated seed for both soybean event FG72 and the unmodified control, this trend was unlikely to be caused by the introduction of the novel traits and was not consistently observed across breeding generations. Therefore the novel traits did not impact seed dormancy.

The susceptibility of soybean event FG72 to various soybean pests and pathogens was evaluated in the field at the same locations as the agronomic characteristic studies (further detail provided below in Section 3: Altered Plant Pest Potential of Soybean Event FG72). No trend in increase or decrease of susceptibility was observed in soybean event FG72 compared to the unmodified control.

The introduction of the 2mepsps and the hppdPfW336 cassettes did not make soybean event FG72 weedy or invasive of natural habitats since none of the soybean's reproductive or growth characteristics were modified, and soybean event FG72's tolerance to abiotic and biotic stresses was unchanged as well. No competitive advantage was conferred to soybean event FG72, other than that conferred by tolerance to glyphosate and isoxaflutole herbicides.

The CFIA considered the changes in usual agronomic practices that may arise from volunteer plants with novel herbicide tolerances. Similarly, the CFIA considered the potential that continued application of the same herbicide in subsequent rotations may lead to increased selection pressure for herbicide resistant weed populations. In order to address these issues, a herbicide stewardship plan which includes integrated pest management strategies should be implemented. These plans may include a recommendation to rotate or combine weed control products with alternate modes of action and to employ other weed control practices.

Bayer CropScience Inc. has submitted a herbicide tolerance stewardship plan which was evaluated by the CFIA. The stewardship plan contains recommendations to address these concerns, as well as appropriate strategies that will allow for the environmentally safe and sustainable deployment of these traits. In addition, the stewardship plan contains strategies for communication to growers and an efficient mechanism allowing growers to report problems to Bayer CropScience Inc. Bayer CropScience Inc. will make this stewardship plan readily available to growers to promote careful management practices for soybean event FG72.

This information, together with the fact that the novel traits have no intended effects on soybean weediness or invasiveness, led the CFIA to conclude that soybean event FG72 has no altered weed or invasiveness potential compared to conventional soybean varieties.

2. Potential for Gene Flow from Soybean Event FG72 to Sexually Compatible Plants Whose Hybrid Offspring May Become More Weedy of More Invasive

Natural hybridization between cultivated soybean and the wild annual species Glycine soja can occur. However, Glycine soja is not naturalized in North America, and although this species is occasionally grown in research plots, there are no reports of its escape to unmanaged habitats nor of it becoming a weed in Canadian agroecosystems. The biology of soybean, as described in the CFIA biology document BIO1996-10, shows that soybeans exhibit a high degree of self-fertilization. Cross pollination is usually less than one percent, suggesting that any pollen flow from cultivated soybeans to related species is minimal.

This information, together with the fact that the novel traits have no intended effects on soybean reproductive biology, led the CFIA to conclude that there is minimal potential for gene flow from soybean event FG72 to related species in Canada.

3. Altered Plant Pest Potential of Soybean Event FG72

The novel traits (tolerance to glyphosate and IFT/DKN herbicides) are unrelated to plant pest potential, and soybean is not considered a plant pest in Canada.

The susceptibility of soybean event FG72 to various soybean pests and pathogens was evaluated in the field at the same locations as the agronomic characteristic studies. The stressors observed included: bean leaf beetle, leafhoppers, white flies, Japanese beetles, caterpillars, aphids, stink bugs, brown spot, bacterial blight, leaf spot, downy mildew, phyllosticta leaf spot, powdery mildew, frogeye leafspot, top die back and sudden death syndrome. Ecological evaluations of soybean event FG72 did not show any increase or decrease in susceptibility to any insect or disease stressor compared to the unmodified control grown at the same locations.

The CFIA therefore concludes that soybean event FG72 does not display any altered pest potential compared to conventional soybean varieties.

4. Potential Impact of Soybean Event FG72 on Non-Target Organisms

The herbicide tolerance traits introduced into soybean event FG72 are unrelated to potential impact on non-target organisms.

Soybean event FG72 expresses the 2mEPSPS protein that differs from the wild type maize EPSPS by two amino acid substitutions. A previous safety assessment of the 2mEPSPS protein (see DD-2008-72) indicated that the 2mEPSPS protein does not display any characteristics of a potential toxin or allergen. In addition, EPSPS proteins naturally occur in plants that have a history of environmental safety. [Glyphosate-tolerant] crops expressing modified EPSPS proteins also have a history of safe use, including soybean, canola, corn and sugar beet. Therefore, no negative impacts resulting from exposure of organisms to the 2mEPSPS protein expressed in soybean event FG72 are expected.

Soybean event FG72 expresses the HPPDW336 protein, which differs from the wild type Pseudomonas fluorescens HPPD by one amino-acid substitution. HPPD enzymes are ubiquitous in nature across all kingdoms: bacteria, fungi, plants and animals. Their enzymatic activity is unrelated to potential toxicity to living organisms. The HPPDW336 protein does not display any characteristics of a potential toxin or allergen (see Part III: Description of the Novel Trait; Section 3: Tolerance to IFT/DKN). Therefore it is very unlikely that the HPPDW336 protein would have any negative impact on organisms interacting with soybean event FG72.

Composition analyses showed that the levels of key nutrients and anti-nutrients in soybean event FG72 grain are comparable to those in conventional soybean varieties. Investigation of the soybean allergen content in soybean event FG72 seeds using two-dimensional gel electrophoresis showed that soybean event FG72 seeds do not contain increased levels of endogenous allergens compared to conventional soybean seeds. In addition, broiler chickens were not adversly affected by the consumption of a diet containing 20% toasted meal from soybean event FG72. Collectively, these results indicate that the composition of soybean event FG72 seeds is similar to that of conventional soybean seeds. Therefore, it is very unlikely that the genetic transformation may have caused unintended changes to the composition of soybean event FG72 tissues that would negatively impact organisms interacting with soybean event FG72.

In addition, field evaluations of soybean event FG72 did not show any increase in resistance to insects or pathogens compared to commercial soybean varieties (see Section 3: Altered Plant Pest Potential of Soybean Event FG72).

The CFIA has therefore determined that the unconfined release of soybean event FG72 will not result in altered impacts on non-target organisms, including humans, compared to conventional soybean varieties.

5. Potential Impact of Soybean Event FG72 on Biodiversity

Soybean event FG72 expresses no novel phenotypic characteristics that would extend its range beyond the current geographic range of soybean production in Canada. The only sexually compatible wild relative of soybean in Canada, Glycine soja, does not occur in unmanaged habitats, and the possibility of soybean outcrossing to Glycine soja is very low. The herbicide tolerance traits of soybean event FG72 are unlikely to have an impact on plant pest potential or non-target organisms. It is therefore unlikely that soybean event FG72 will have any direct effects on biodiversity, in comparison to the effects that would be expected from the cultivation of currently grown soybean varieties.

Soybean event FG72 has tolerance to glyphosate and IFT/DKN herbicides. The use of these herbicides in cropping systems has the intended effect of reducing local weed populations within agroecosystems. This may result in a reduction in local weed species biodiversity, and may have effects on other trophic levels which utilize these weed species. It must be noted however that the goal of reduction in weed biodiversity in agricultural fields is not unique to the use of PNTs, soybean event FG72 or the cultivation of soybean. It is therefore unlikely that soybean event FG72 will have significant indirect effects on biodiversity, in comparison to the effects that would be expected from the cultivation of currently cultivated soybean varieties.

The CFIA has concluded that the novel genes and their corresponding traits do not confer to soybean event FG72 any characteristics that would result in unintended environmental effects following unconfined release. The CFIA has therefore concluded that the potential impact on biodiversity of soybean event FG72 is unlikely to be different from that of soybean varieties currently grown in Canada.

V. Criteria for the Livestock Feed Assessment

The AFD considered nutrient and anti-nutrient profiles; the safety of feed ingredients derived from soybean event FG72, including the presence of gene products, residues, and metabolites in terms of animal health and human safety as it relates to the potential transfer of residues into foods of animal origin, and worker/bystander exposure to the feed; and whether feeds derived from soybean event FG72 meet the definitions and requirements of feeds as listed in Schedule IV. of the Feeds Regulations.

1. Potential Impact of Soybean Event FG72 on Livestock Nutrition

Nutrient and anti-nutrient composition

The compositional equivalence of soybean event FG72 (sprayed with IFT and glyphosate herbicides, and unsprayed) to an unmodified control (Jack) and three conventional soybean varieties was examined at ten replicated field sites in the US during the 2008 growing season. Seeds were planted in a randomized complete block design with 3 plots of each transgenic (sprayed and unsprayed) and control Jack. One plot of each of the three conventional varieties was planted at each site. Soybean seeds were harvested at normal maturity and stored at ambient temperature prior to shipment to Bayer Crop Science Inc. Seed samples were sub-sampled and frozen at -20°C until composition analyses were conducted. Seed samples were analysed for proximate, acid detergent fibre (ADF), neutral detergent fibre (NDF), amino acids, fatty acids, vitamins, minerals, isoflavones (diadzin, glycitin, genistin, diadzein, glycitein, genistein) and anti-nutrients (phytic acid, trypsin inhibitor, lectin, stachyose and raffinose). Composition data was analysed statistically using analysis of variance and statistical differences among soybean varieties were determined (P<0.05). Except for ash, no statistically significant differences were observed between soybean event FG72 (treated and untreated) and the unmodified control for moisture, crude protein, fat, ADF and NDF. The mean value for ash in soybean event FG72 was however within the range of conventional soybean varieties and was not considered biologically relevant. No significant differences were observed between soybean event FG72 and unmodified control soybeans for all amino acids analysed. Palmitic, stearic, oleic, linoleic, linolenic, arachidic, eicosenoic and behenic acids were different in soybean event FG72 compared to the unmodified control, but the means values were within the normal variation of conventional soybean varieties and literature values and therefore the differences were not considered biologically relevant. Calcium, magnesium and sodium were significantly different in soybean event FG72 compared to the unmodified control, but the means were within the range of conventional soybean varieties and published literature values. Minor statistically significant differences were observed between the soybean event FG72 and the unmodified control for vitamin B1, gamma and total tocopherols, glycitin, genistin and total isoflavones; however these means were within the normal variation for conventional soybean varieties, and therefore not considered biologically relevant. Except for raffinose, no statistical significant differences were observed between soybean event FG72 and the unmodified control for lectin, phytic acid, trypsin inhibitor and stachyose. The mean values for raffinose was within the natural variation of the conventional soybean varieties.

Broiler chicken performance

420 broiler chickens were distributed randomly to 14 pens (10 birds per pen) to examine the health and performance of birds from feeding meal from soybean event FG72 and that from an unmodified control and a conventional soybean variety, in a 42-day trial. Meal from both the control varieties and from soybean event FG7 was incorporated at about 20% of the diet. Meal from soybean event FG72 was prepared from soybean treated with both glyphosate and IFT at Bayer CropScience Inc.'s expected commercial application rates. Feed and water were provided on a continual basis. Data was collected on broiler mortality, body weight gain, feed intake, feed conversion efficiencies, market dressed carcass, muscle (breast, thigh, leg and wing) and abdominal fat pad weights. The growth performance and mortality data of birds on soybean event FG72 diets were not different from birds on the diets containing the unmodified control and conventional soybean variety over the entire trial. No statistically significant differences were observed between broilers fed soybean event FG72 diets and the unmodified control and conventional soybean variety diets for feed intake, average daily gain and feed efficiency. Carcass yield measurements and tissue weights were not different for broilers fed diets containing soybean event FG72 meal compared to those fed diets containing the unmodified control and conventional soybean meals. No unexpected effects on broiler performance and health were found when broilers were fed diets containing soybean event FG72 meal.

Conclusion

It was concluded based on the evidence provided by Bayer Crop Science Inc. that the nutritional composition of soybean event FG72 is similar to conventional soybean varieties. No biologically relevant differences were observed on the performance and health of birds consuming diets containing soybean event FG72 meal.

2. Potential Impact of Soybean Event FG72 on Animal Health and Human Safety as it Relates to the Potential Transfer of Residues into Foods of Animal Origin, and Worker/Bystander Exposure to the Feed

Soybean event FG72 is tolerant to glyphosate and IFT/DKN as a result of insertion of genes encoding 2mEPSPS and HPPDW336 proteins, respectively. The assessment of soybean event FG72 evaluated the impact of the following potential hazards relative to the safety of feed ingredients derived from this event:

  • The presence of novel proteins 2mEPSPS and HPPDW336
  • The chemical pesticide residue profile.

Novel 2mEPSPS and HPPDW336 proteins

The 2mEPSPS protein shares no significant biologically relevant sequence homology with any known toxins or allergens and lacks a mode of action that suggests that it is intrinsically toxic. The 2mEPSPS protein was previously assessed for Bayer CropScience Inc.'s cotton event GHB614; and it has been determined, based on the established equivalence, that the cotton event GHB614 safety data may be used to support the safety of the 2mEPSPS from soybean event FG72. These studies indicated that the 2mEPSPS protein is heat labile and rapidly degraded under conditions similar to those encountered in the gastrointestinal tract. No signs of toxicity were demonstrated in the original single-dose oral toxicity studies in mice using purified 2mEPSPS proteins from an E. coli over expression system at doses up to 2000 mg/kg body weight. These factors support the lack of intrinsic toxicity or allergenicity of the 2mEPSPS protein. Furthermore, the 2mEPSPS protein has history of safe use, having been approved in prior events; and is found throughout the food chain.

The HPPDW336 protein shares no significant biologically relevant sequence homology with any known toxins or allergens and lacks modes of action that suggest it may be intrinsically toxic. This protein is also heat labile and rapidly degraded under conditions similar to those encountered in the gastrointestinal tract. No signs of toxicity were demonstrated in single-dose oral toxicity studies in mice using purified HPPDW336 proteins from an E. coli over expression system at doses up to 970 mg/kg body weight. These factors support the lack of intrinsic toxicity or allergenicity of the HPPDW336 protein.

Furthermore, the lack of performance effects or significant health observations in the broiler study using soybean meal derived from FG72 supports the safety of 2mEPSPS protein and HPPDW336 protein novel gene products.

Chemical pesticide residue profile

The safety of herbicide residues and metabolites in soybean event FG72, following application of the herbicides, was also evaluated as part of the feed safety assessment. It was concluded, that potential glyphosate residues would not be a safety concern for livestock or for humans, when comparing the estimated exposure to established legal residue limits in Canada and the US. The livestock feeding trial in broilers was conducted using soybean meal derived from FG72 treated with glyphosate at a typical application rate used in glyphosate tolerant crops, and IFT at the expected commercial use rate. The trial did not show any evidence of performance or health effects, providing support for the safety of soybean meal derived from event FG72, relative to the proposed use patterns of glyphosate and IFT.

It was determined that the IFT and metabolites (including DKN) in livestock commodities: soybean seeds, soybean meal, soybean oil, soybean milk, soybean hulls and aspirated grain fractions, are not likely to present a safety concern to livestock or humans, when comparing the estimated exposure to established legal residue limits in Canada and the US.

No authorization for forage or hay produced from soybean event FG72 treated with IFT has been granted at this time, as there were not sufficient data available to support the inclusion of IFT treated forage and hay as feed. The CFIA has, in this case, granted an exemption for the provision of additional residue data for forage and hay, as Bayer CropScience Inc. has indicated that they will not be pursuing a herbicide authorization for IFT/DKN in either soybean forage or hay. The exemption for the provision of residue data is supported by current agricultural practices indicating the negligible usage of soybean byproducts for forage and hay.

Conclusions

Feed ingredients derived from soybean event FG72, with the exception of forage or hay produced from the IFT and soybean event FG72 combination, are considered to meet present ingredient definitions for soybean, and as such are approved for use as livestock feed in Canada.

VI. New Information Requirements

If at any time, Bayer CropScience Inc. becomes aware of any information regarding risk to the environment, including risk to human or animal health, which could result from release of soybean event FG72 in Canada or elsewhere, Bayer CropScience Inc. is required to immediately provide such information to the CFIA. On the basis of such new information, the CFIA will re-evaluate the potential impact of soybean event FG72 on the environment, livestock and human health, and may re-evaluate its decision with respect to the livestock feed use and environmental release authorizations of soybean event FG72.

VII. Regulatory Decision

Based on the review of the data and information submitted by Bayer CropScience Inc. and other relevant information, the Plant and Biotechnology Risk Assessment Unit of the Plant Health Science Directorate, CFIA has determined that soybean event FG72 does not present altered environmental risk when compared to currently commercialized soybean varieties in Canada.

Based on the review of submitted data and information by Bayer CropScience Inc., including comparisons of soybean event FG72 with its unmodified soybean counterpart, the Animal Feed Division of the Animal Health Directorate, CFIA, has concluded that the novel 2mEPSPS and HPPDW336 protein-based herbicide tolerance traits will not confer to soybean event FG72 any characteristic that would raise any concerns regarding the safety or nutritional composition of soybean event FG72. Grain soybean, soybean oil, and soybean byproducts, excepting soybean forage and hay that have been treated with IFT, are currently listed in Schedule IV. of the Feeds Regulations and are, therefore, approved for use in livestock feeds in Canada. Feed ingredients, other than hay and forage that have been treated with IFT, from soybean event FG72 have been assessed and found to be as safe as and as nutritious as traditional soybean varieties.

Unconfined release into the environment and use as livestock feed of soybean event FG72 is therefore authorized by the Plant Biosafety Office of the Plant Health and Biosecurity Directorate and the Animal Feed Division of the Animal Health Directorate as of June 26, 2012. Any Glycine max lines derived from soybean event FG72 may also be released into the environment and used as livestock feed, provided that (i) no inter-specific crosses are performed, (ii) the intended uses are similar, (iii) it is known based on characterization that these plants do not display any additional novel traits and are substantially equivalent to currently grown soybean varieties in Canada, in terms of their potential environmental impact and livestock feed safety, and (iv) the novel genes are expressed at levels similar to those in the authorized line.

Additionally, with respect to its use as livestock feed, FG72 must meet the restrictions specific to IFT-treated forage and hay for feed set out in the this authorization.

Soybean event FG72 is subject to the same phytosanitary import requirements as its unmodified counterpart; and is required to meet the requirements of other jurisdictions; including but not limited to, the Food & Drugs Act, and the Pest Control Products Act.

Please refer to Health Canada's Decisions on Novel Foods for a description of the food safety assessment of soybean event FG72.

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