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Decision document DD2016-113: Determination of the safety of Monsanto Canada Inc.'s corn (Zea mays L.) event MON 87419

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This decision document has been prepared to explain the regulatory decisions reached under Directive 94-08 - Assessment Criteria for Determining Environmental Safety of Plants with Novel Traits, its companion document BIO1994-11 - The Biology of Zea mays (L.) (Corn) and Section 2.6 - Guidelines for the Assessment of Novel Feeds: Plant Sources, of Chapter 2 of the RG-1 Regulatory Guidance: Feed Registration Procedures and Labelling Standards.

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 Monsanto Canada Inc. This information concerns the herbicide-tolerant corn event MON 87419. The CFIA has determined that this plant with novel traits (PNT) does not present altered environmental risk nor, as a novel feed, does it present livestock feed safety or nutrition concerns when compared to corn varieties currently grown and permitted to be used as livestock feed in Canada.

Taking into account these evaluations, unconfined release into the environment and uses as livestock feed of corn event MON 87419 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, respectively, as of January 28, 2016. Any corn lines derived from the event MON 87419 may also be released into the environment and used as livestock feed, provided that:

  1. no inter-specific crosses are performed
  2. the intended use(s) are similar
  3. it is known based on characterization that these plants do not display any additional novel traits and are substantially equivalent to corn varieties that are currently grown and permitted to be used as livestock feed in Canada, in terms of their potential environmental impact and livestock feed safety; and
  4. the novel genes are expressed at levels similar to that of the authorized line

Additionally, with respect to its unconfined release into the environment, an appropriate herbicide tolerance management plan should be implemented.

Corn event MON 87419 is subject to the same phytosanitary import requirements as unmodified corn varieties. Corn event MON 87419 must also meet the requirements of other Canadian legislation, including but not limited to the requirements set out in the Food and Drugs Act and the Pest Control Products Act.

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

January 28, 2016

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

On this page

  1. Brief identification of the modified plant
  2. Background information
  3. Description of the novel traits
    1. Development method
    2. Tolerance to dicamba herbicide
    3. Tolerance to glufosinate-ammonium herbicide
    4. Stable integration into the plant genome
  4. Criteria for the environmental assessment
    1. Potential for corn event MON 87419 to become a weed of agriculture or be invasive of natural habitats
    2. Potential for gene flow from corn event MON 87419 to sexually compatible plants whose hybrid offspring may become more weedy or more invasive
    3. Potential for corn event MON 87419 to become a plant pest
    4. Potential impact of corn event MON 87419 and its gene products on non-target organisms, including humans
    5. Potential impact of corn event MON 87419 on biodiversity
  5. Criteria for the livestock feed assessment
    1. Potential impact of corn event MON 87419 on livestock nutrition
    2. Potential impact of corn event MON 87419 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: Corn event MON 87419, OECD Unique Identifier MON-87419-8

Applicant: Monsanto Canada Inc.

Plant species: Corn (Zea mays L.)

Novel traits: Tolerance to dicamba herbicide; tolerance to glufosinate-ammonium herbicide

Trait introduction method: Agrobacterium-mediated transformation

Intended use of the modified plant: Corn event MON 87419 is intended for human consumption and livestock feed uses. Corn event MON 87419 is not intended to be grown outside the normal production area for corn in Canada.

II. Background information

Monsanto Canada Inc. has developed a corn event that is tolerant to the herbicides dicamba and glufosinate-ammonium. Corn event MON 87419 was developed using recombinant deoxyribonucleic acid (rDNA) technology, resulting in the introduction of the dicamba mono-oxygenase (dmo) gene and the phosphinothricin N-acetyltransferase (pat) gene. The dmo gene is derived from the bacterium Stenotrophomonas maltophilia and encodes a dicamba mono-oxygenase (DMO) protein, which confers tolerance to the herbicide dicamba. The pat gene is derived from the soil bacterium Streptomyces viridochromogenes and encodes the phosphinothricin N-acetyltransferase (PAT) protein, which confers tolerance to the herbicide glufosinate-ammonium.

Monsanto Canada Inc. has provided information on the identity of corn event MON 87419; a detailed description of the transformation method; and information on insert copy number and intactness, levels of protein expression in the plant and the role of the inserted sequences. The novel proteins were identified and characterized. Information was provided for the evaluation of the potential toxicity of the novel proteins to livestock and non-target organisms and potential allergenicity of the novel proteins to humans and livestock. Information was also provided for the evaluation of herbicide residues in the feed commodities derived from the crop, following the intended herbicide application.

A hybrid of corn event MON 87419 (hereafter referred to as the corn event MON 87419 hybrid) and an unmodified corn variety (hereafter referred to as the unmodified control corn hybrid) was field tested in the United States (US) at nine sites in 2013 and three sites in 2014. The locations of these trials share similar environmental and agronomic conditions to corn production areas in Canada and were considered representative of major Canadian corn growing regions. The corn event MON 87419 hybrid was compared to an unmodified control corn hybrid with a similar genetic background. Several reference corn hybrids were also included in the field trials to establish ranges of comparative values that are typical of currently grown corn varieties.

Agronomic characteristics of the corn event MON 87419 hybrid, including early stand count, days to 50% pollen shed, days to 50% silking, stay green rating, ear height, plant height, dropped ears, stalk lodged plants, root lodged plants, final stand count, grain moisture, test weight and grain yield, were compared to those of the unmodified control corn hybrid and to the range established by the reference corn hybrids.

Corn event MON 87419 was field tested at five replicated field trial sites in the US during the 2013 growing season. Nutritional components of grain and forage from the corn event MON 87419 such as protein, fat, moisture, ash, carbohydrates, fiber, amino acids, fatty acids, vitamins, minerals, secondary metabolites and anti-nutrients, were compared with those of the unmodified control corn variety and to the range established for corn in published literature and the Agriculture and Food Systems Institute (AFSI) database (AFSI, 2011).

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 Directive 94-08 - Assessment Criteria for Determining Environmental Safety of Plants with Novel Traits. The PBRA Unit has considered:

The Animal Feed Division (AFD) of the CFIA has also reviewed the above information with respect to the assessment criteria for determining the safety and nutrition of livestock feed, as described in Section 2.6 - Guidelines for the Assessment of Novel Feeds: Plant Sources, of Chapter 2 of the RG-1 Regulatory Guidance: Feed Registration Procedures and Labelling Standards.

The AFD has considered both intended and unintended effects and similarities and differences between corn event MON 87419 and unmodified corn varieties relative to the safety and nutrition of feed ingredients derived from corn event MON 87419 for their intended purpose, including:

The AFD has also considered whether feeds derived from corn event MON 87419 meet the definitions and requirements of feeds as listed in Schedule IV of the Feeds Regulations.

III. Description of the novel traits

1. Development method

Corn event MON 87419 was developed through Agrobacterium-mediated transformation of immature embryos from conventional corn seeds using a transformation plasmid vector that includes two separate T-DNAs. The first T-DNA, designated as T-DNA I, contains the dmo and the pat expression cassettes. The second T-DNA, designated as T-DNA II, contains the cp4 epsps expression cassette. Expression of the cp4 epsps gene confers tolerance to the herbicide glyphosate. Following cultivation with Agrobacterium, the embryos were transferred to a selection medium containing glyphosate to eliminate cells that were not transformed and thereby select cells containing T-DNA-II or T-DNA I + T-DNA II. During subsequent breeding the unlinked insertions of T-DNA I and T-DNA II were segregated. The plants containing only the dmo and the pat genes were selected by molecular analysis, while the plants containing the cp4 epsps gene were eliminated from subsequent breeding. Corn event MON 87419 was identified as a successful transformant and was chosen for further development. Therefore, corn event MON 87419 contains only the dmo and pat genes and not the cp4 epsps gene.

2. Tolerance to dicamba herbicide

Dicamba is a group 4 herbicide that mimics indole-3-acetic acid (IAA), a natural plant hormone of the auxin class. Dicamba application causes rapid and uncontrolled growth of the stems, petioles and leaves of sensitive plants, leading to the destruction of vascular tissue and eventually plant death. Dicamba is used for broadleaf weed control on grain crops, pastures and non-crop areas.

Corn event MON 87419 was developed to be tolerant to the herbicide dicamba by incorporation of the dmo gene. The dmo gene encodes the enzyme DMO, which converts dicamba to non-herbicidal 3,6-dichlorosalicylic acid. Introduction of the dmo gene into corn event MON 87419 confers commercial-level tolerance to the herbicide dicamba. The dmo gene was derived from S. maltophilia, a gram-negative bacterium commonly present in soil, plants and aquatic environments. The DMO protein in corn event MON 87419 is identical to the native DMO protein except for insertion of a single amino-acid at position 2 from the N-terminus and 12 amino-acids from a chloroplast transit peptide which directs transport of the DMO protein to the chloroplast.

DMO protein expression in corn event MON 87419 is driven by a constitutive promoter. Samples of corn tissues from plants sprayed with dicamba and glufosinate-ammoniun were collected from five field trial sites in the US. The average DMO protein levels across all sites, expressed in micro-grams protein per gram dry weight tissue (µg/g dwt), as evaluated by enzyme-linked immunosorbent assay (ELISA) were as follows: 26 ± 6.6 µg/g dwt in leaf, 7.4 ± 1.4 µg/g dwt in root, 6.0 ± 2.7 µg/g dwt in forage, 0.19 ± 0.048 µg/g dwt in grain.

To obtain sufficient quantities of DMO protein for assessment of environmental and feed safety, it was necessary to express the DMO protein in an Escherichia coli production system. Equivalency was demonstrated between the corn event MON 87419-produced DMO protein and the E. coli-produced DMO protein. Equivalency was established based on similar molecular weights, immunoreactivities, tryptic peptide mass signatures, N-terminal sequences, functional activities and lack of glycosylation. Based on the results, both proteins were found to be equivalent. Demonstration of the equivalence between the DMO protein produced in E. coli and the DMO protein produced in corn event MON 87419 allows the DMO protein produced in E. coli to be used in studies to confirm safety of the DMO protein produced in corn event MON 87419. The data on E. coli-produced DMO digestibility and lack of acute oral toxicity (see paragraph below) was previously submitted to the CFIA to confirm the safety of dicamba and glufosinate-ammonium tolerant cotton event MON 88701 (DD2014-104).

The potential allergenicity and toxicity of the DMO protein to livestock and non-target organisms was evaluated. The weight of evidence indicates that the DMO protein is unlikely to be allergenic, based on the following information. The source of the dmo gene, S. maltophilia, is not commonly associated with allergenicity and the DMO protein amino acid sequence lacks relevant similarities to known allergens. Unlike many allergens, the E. coli-produced DMO protein was shown experimentally to be rapidly degraded in simulated gastric fluid and simulated intestinal fluid. Finally, the DMO protein expressed in corn event MON 87419 was shown experimentally to be non-glycosylated. It was also concluded that the DMO protein is unlikely to be toxic to livestock and non-target organisms because it lacks a mode of action to suggest that it is intrinsically toxic to livestock or non-target organisms, because the DMO protein amino-acid sequence lacks relevant similarities to known toxins and because no adverse effects were observed when the E. coli-produced DMO protein was ingested by mice at doses of 283 mg/kg body weight, the highest dose tested.

For a more detailed discussion of the potential allergenicity and toxicity of the DMO protein, see Section V, part 2: Potential Impact of Corn Event MON 87419 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.

3. Tolerance to glufosinate-ammonium herbicide

Glufosinate-ammonium herbicide inhibits the plant enzyme glutamine synthetase. Inhibiting glutamine synthetase results in reduced glutamine synthesis, and accumulation of lethal levels of ammonia in susceptible plants. Ammonia is produced by plants as a result of normal metabolic processes, but elevated levels of ammonia can interfere with essential plant processes, like photosynthesis, leading to plant death.

Corn event MON 87419 was developed to be tolerant to the herbicide glufosinate-ammonium by incorporation of the pat gene. The pat gene encodes the enzyme PAT, which acylates the primary amino group of glufosinate-ammonium, rendering the herbicide inactive. Introduction of the pat gene into corn event MON 87419 confers commercial-level tolerance to the herbicide glufosinate-ammonium. The pat gene was derived from S. viridochromogenes, a gram-positive soil bacterium and the PAT protein produced in corn event MON 87419 is identical to the native enzyme, in terms of its amino acid sequence.

The pat gene expression in corn event MON 87419 is driven by a constitutive promoter. Samples of corn tissues from plants sprayed with dicamba and glufosinate-ammonium were collected from five field trial sites in the US. The average PAT protein levels across all sites, as evaluated by ELISA were as follows: 11 ± 2.7 µg/g dwt in leaf, 7.7 ± 1.3 µg/g dwt in root, 5.0 ± 1.6 µg/g dwt in forage, 0.93 ± 0.27 µg/g dwt in grain.

To obtain sufficient quantities of PAT protein for assessment of environmental and feed safety, it was necessary to express the pat in microbial production systems. Equivalency was demonstrated between corn event MON 87419 and E. coli-produced PAT protein. Equivalency was established based on similar molecular weights, immunoreactivities, tryptic peptide mass signatures, N-terminal sequences, functional activities, and lack of glycosylation. Based on the results, both proteins were found to be equivalent. Demonstration of the equivalence between the PAT protein produced in E. coli and the PAT protein produced in corn event MON 87419 allows the PAT protein produced in E. coli to be used in studies to confirm safety of the PAT protein produced in corn event MON 87419. The data on E. coli-produced PAT digestibility and lack of acute oral toxicity (see paragraph below) was previously submitted to the CFIA to confirm the safety of dicamba and glufosinate-ammonium tolerant cotton event MON 88701 (DD2014-104).

The PAT protein expressed in corn event MON 87419 is identical to the PAT protein found in several commercial corn products lines, including T14/T25 (DD98-22), 1507 (DD2002-41), and 59122 (DD2005-55). The PAT protein has therefore a history of safe use in Canada, and as such is not expected to be toxic or allergenic. Nevertheless, the potential allergenicity and toxicity of the PAT protein expressed in corn event MON 87419 were evaluated further. The weight of evidence indicates that the PAT protein is unlikely to be allergenic, based on the following information. The source of the pat gene, S. viridochromogenes, is not commonly associated with allergenicity and the PAT protein amino acid sequence lacks relevant similarities to known allergens. Unlike many allergens, the E. coli-produced PAT protein was shown experimentally to be rapidly degraded in simulated gastric fluid and simulated intestinal fluid. Finally, corn event MON 87419 PAT protein was shown experimentally to be non-glycosylated. It was also concluded that the PAT protein is unlikely to be toxic to livestock and non-target organisms because it lacks a mode of action to suggest that it is intrinsically toxic to livestock or non-target organisms, because the PAT protein amino-acid sequence lacks relevant similarities to known toxins and because no adverse effects were observed when the E. coli-produced PAT protein was ingested by mice at doses of 1086 mg/kg body weight, the highest dose tested.

For a more detailed discussion of the potential allergenicity and toxicity of the PAT protein, see Section V, part 2: Potential Impact of Corn Event MON 87419 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.

4. Stable integration into the plant genome

Molecular characterization by next generation sequencing junction sequencing analysis, DNA sequencing analysis and Southern blot analysis demonstrated that corn event MON 87419 contains one intact copy of the dmo and pat genes, and their associated regulatory elements inserted at a single site in the corn genome. No additional elements, including intact or partial DNA fragments or backbone sequences from the plasmid vector, linked or unlinked to the intact insert, were detected in corn event MON 87419.

The stability of the inserted DNA was demonstrated by next generation sequencing junction sequencing analysis, Southern blot analysis and detection of the DMO and PAT proteins across five generations in the breeding history of corn event MON 87419.

The inheritance pattern of the insert across three segregating generations of corn event MON 87419 showed that the insert segregates according to the Mendelian rules of inheritance for a single genetic locus.

IV. Criteria for the environmental assessment

1. Potential for corn event MON 87419 to become a weed of agriculture or be invasive of natural habitats

The CFIA biology document BIO1994-11 - The Biology of Zea mays L. (Corn) states that unmodified plants of this species are not invasive of unmanaged habitats in Canada. Corn does not possess the potential to become weedy due to the lack of seed dormancy, the non-shattering nature of corn cobs and the poor competitive ability of seedlings. According to the information provided by Monsanto Canada Inc., corn event MON 87419 was determined not to be significantly different from unmodified corn in this respect.

The CFIA evaluated data submitted by Monsanto Canada Inc. on the reproductive biology and life history traits of corn event MON 87419. As previously mentioned, this event was field tested in the US at 9 sites in 2013 and 3 sites in 2014. It was determined that the US locations share similar environmental and agronomic conditions to corn production areas in southern Ontario and Quebec, therefore they were considered representative of the major Canadian corn growing regions. During the field trials, the corn event MON 87419 hybrid was compared to an unmodified control corn hybrid with a similar genetic background. Reference corn hybrids were also included in these trials to establish ranges of comparative values that are representative of currently grown corn varieties. Phenotypic and agronomic traits were evaluated, covering a broad range of characteristics that encompass the entire life cycle of the corn plant. The traits included early stand count, days to 50% pollen shed, days to 50% silking, stay green rating, ear height, plant height, dropped ears, stalk lodged plants, root lodged plants, final stand count, grain moisture, test weight and grain yield. Although instances of statistically significant differences were observed between the corn event MON 87419 hybrid and the unmodified control corn hybrid for some traits in the individual-site analyses, there were no consistent trends in the data across locations that would indicate the differences were due to the genetic modification. Therefore, the differences were not considered to be biologically meaningful and the results support a conclusion of phenotypic and agronomic equivalence to currently grown corn varieties.

Monsanto Canada Inc. provided information on the dormancy and germination of corn event MON 87419 seed under seven different temperature regimes. Seed germination characteristics were evaluated, including percent germinated seed (normal and/or abnormal), percent hard seed, percent dead seed and percent firm swollen seed. A corn event MON 87419 hybrid was compared to an unmodified control corn hybrid with a similar genetic background. Eight reference corn hybrids were included to provide a range of comparative values for each germination characteristic. Seed lots were produced at three sites in the US. Statistically significant differences were observed between the corn event MON 87419 hybrid and the unmodified control corn hybrid for three temperature regimes for the percent of germinated seed. However the values for the corn event MON 87419 hybrid were only slightly higher than that of the unmodified control corn hybrid, and for two of the three temperature regimes were within the range of values established for the reference corn hybrids. Therefore these instances of statistically significant differences are not considered biologically meaningful. Moreover, the lack of hard seed indicated that corn event MON 87419 does not possess seed dormancy. Therefore, the introduction of the novel traits did not impact the germination of the corn seed and did not confer dormancy to the corn seed.

The response of the corn event MON 87419 hybrid to abiotic stressors was observed at nine sites in 2013 and three sites in 2014. The stressors included cold, drought, flooding, hail, heat, mineral toxicity, nutrient deficiency, soil compaction and wind. No trend in increased or decreased susceptibility to these abiotic stressors was observed in the corn event MON 87419 hybrid compared to the unmodified control corn hybrid.

The susceptibility of the corn event MON 87419 hybrid to corn pests and pathogens was evaluated at nine sites in 2013 and three sites in 2014 (further detail provided below in Section IV, part 3: Potential for Corn Event MON 87419 to Become a Plant Pest). No trend in increased or decreased susceptibility to pests or pathogens was observed in corn event MON 87419 hybrid compared to the unmodified control hybrid.

No competitive advantage was conferred to plants of corn event MON 87419, other than that conferred by tolerance to the dicamba and glufosinate-ammonium herbicides, as the reproductive characteristics, growth characteristics and tolerance to biotic and abiotic stressors of corn event MON 87419 were comparable to those of the unmodified control corn hybrid. Tolerance to the dicamba and glufosinate-ammonium herbicides provides a competitive advantage only when one, or both, of these herbicides are used and will not, in and of itself, make the herbicide-tolerant plant weedier or more invasive of natural habitats. Corn event MON 87419 plants growing as volunteers will not be controlled if the dicamba and glufosinate-ammonium herbicides are used as the only weed control tools. However, control of corn event MON 87419 as a volunteer weed in subsequent crops or in fallow ground can be achieved by the use of other classes of herbicides or by mechanical means.

The novel traits have no intended or observed effects on weediness or invasiveness. The CFIA has therefore concluded that corn event MON 87419 has no altered weediness or invasiveness potential in Canada compared to currently grown corn varieties.

The CFIA considers the changes in usual agronomic practices that may arise from volunteer plants with novel herbicide tolerances. Similarly, the CFIA considers the potential that continued application of the same herbicide in subsequent rotations may lead to increased selection pressure for herbicide-tolerant weed populations. To address these issues, a herbicide tolerance management plan, which includes integrated weed management strategies, should be implemented. This plan may include a recommendation to rotate or combine weed management products with alternate modes of action and to employ other weed management practices. According to Monsanto Canada Inc., corn event MON 87419 is not intended to be cultivated as an individual event in Canada. Before corn event MON 87419 is cultivated in Canada as an individual event or in combination with other corn events in stacked/pyramided products, Monsanto Canada Inc. must submit a herbicide tolerance management plan to the CFIA.

2. Potential for gene flow from corn event MON 87419 to sexually compatible plants whose hybrid offspring may become more weedy or more invasive

The CFIA biology document BIO1994-11 - The Biology of Zea mays (L.) (Corn) states that there are no sexually compatible species in Canada that can hybridize with corn. The dicamba and glufosinate-ammonium tolerance traits introduced into corn event MON 87419 have no intended effects on corn reproductive biology.

The CFIA has therefore concluded that gene flow from corn event MON 87419 to sexually compatible relatives is not possible in Canada.

3. Potential for corn event MON 87419 to become a plant pest

Corn is not considered a plant pest in Canada and the dicamba and glufosinate-ammonium tolerance traits introduced into corn event MON 87419 are unrelated to plant pest potential (i.e., the potential for the plant to harbor new or increased populations of pathogens or pests).

The susceptibility of the corn event MON 87419 hybrid to corn pests and pathogens was evaluated in the field at the same locations as the agronomic characteristic studies. The diseases (pathogens) observed included anthracnose, bacterial blight, crazy top, ear rot, eyespot, Fusarium spp., Goss's bacterial wilt, gray leaf spot, leaf blight, Northern leaf spot, Pythium spp., rust, smut, stalk rot and Stewart's bacterial wilt. Damage from the following pests was also evaluated: aphids, armyworms, billbugs, corn earworms, corn flea beetles, corn rootworm beetles, black cutworms, European corn borer, grape colaspis, grasshoppers, Japanese beetles, sap beetles, spider mites, and stink bugs. The evaluations of the corn event MON 87419 hybrid did not show any increased or decreased susceptibility to these corn pests and pathogens compared to the unmodified control corn hybrid.

In addition, sticky trap and visual count collections performed at three sites in 2013 showed similar abundance of corn pests (corn flea beetles, corn rootworm beetles, sap beetles, leafhoppers, plant hoppers, spider mites) in plots of the corn event MON 87419 hybrid compared to plots of the unmodified control corn hybrid.

Based on the above information, the CFIA has concluded that corn event MON 87419 does not display any altered plant pest potential compared to currently grown corn varieties.

4. Potential impact of corn event MON 87419 and its gene products on non-target organisms, including humans

The dicamba and glufosinate-ammonium tolerance traits introduced into corn event MON 87419 are unrelated to a potential impact on non-target organisms.

Detailed characterization of the DMO and PAT proteins expressed in corn event MON 87419 led to the conclusion that these proteins do not display any characteristic of a potential toxin or allergen (see Section V, part 2: Potential Impact of Corn Event MON 87419 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). Therefore, no negative impacts resulting from exposure of organisms to the DMO and PAT proteins expressed in corn event MON 87419 are expected.

Composition analyses showed that the levels of key nutrients and anti-nutrients in grain and forage from corn event MON 87419 are comparable to those in the unmodified control corn hybrid (see Section V, part 1: Potential Impact of Corn Event MON 87419 on Livestock Nutrition). Therefore, it is very unlikely that the introduction of the novel traits may have caused unintended changes to the composition of corn event MON 87419 tissues that would negatively impact organisms interacting with corn event MON 87419.

Monsanto Canada Inc. quantitatively assessed the arthropod abundance at three trial sites, using sticky traps and visual counts at five collection times in 2013. The beneficial arthropods observed included lacewings, ladybird beetles, minute pirate bugs, parasitic wasps, syrphid flies and spiders. The abundance of minute pirate bugs was lower on the corn event MON 87419 hybrid than on the unmodified control corn hybrid in visual counts at one site. However, this difference was not considered biologically meaningful as it was not consistently detected across collection methods and sites, and the mean value for abundance of minute pirate bugs on corn event MON 87419 hybrid was within the reference range established for the reference corn hybrids included in the same field trial. The abundance of spiders was higher on corn event MON 87419 hybrid than on the unmodified corn control corn hybrid. However this difference was not considered biologically meaningful as it was not consistently detected across collection methods and sites. No other statistically significant differences were detected between the corn event MON 87419 hybrid and the unmodified control corn hybrid in terms of beneficial arthropod abundance. These observations showed similar abundance of beneficial arthropods in plots of the corn event MON 87419 hybrid compared to plots of the unmodified control corn hybrid.

Field evaluations of corn event MON 87419 hybrid did not show any increased resistance to pathogens compared to the unmodified control corn hybrid (see Section IV, part 3: Potential for Corn Event MON 87419 to Become a Plant Pest).

Collectively, these information elements indicate that the interactions between corn event MON 87419 and the populations of animals and microorganisms interacting with corn crops will be similar to currently grown corn varieties.

Based on the above information, the CFIA has concluded that the unconfined release of corn event MON 87419 in Canada will not result in altered impacts on non-target organisms, including humans, compared to currently grown corn varieties.

5. Potential impact of corn event MON 87419 on biodiversity

Corn event MON 87419 expresses no novel phenotypic characteristics that would extend its geographic range beyond the current range of corn production in Canada. Since corn has no sexually compatible relatives with which it can outcross in Canada, there will be no transfer of the novel traits to other species in unmanaged environments. Corn event MON 87419 is unlikely to cause adverse effects on non-target organisms and does not display increased weediness, invasiveness or plant pest potential. It is therefore unlikely that corn event MON 87419 will have any direct effects on biodiversity, in comparison to the effects that would be expected from the cultivation of the corn varieties that are currently grown in Canada.

Corn event MON 87419 has tolerance to the herbicides dicamba and glufosinate-ammonium. The use of these herbicides in cropping systems has the intended effect of reducing local weed populations within agro-ecosystems. This may result in a reduction in local weed species biodiversity, and may have effects on other trophic levels that utilize these weed species. It must be noted, however, that the goal of reducing weed biodiversity in agricultural fields is not unique to the use of PNTs, corn event MON 87419 or the cultivation of corn. It is therefore unlikely that corn event MON 87419 will have any indirect effects on biodiversity, in comparison to the effects that would be expected from cultivation of currently grown corn varieties.

The CFIA has concluded that the introduced genes and their corresponding novel traits do not confer to corn event MON 87419 any characteristic that would result in unintended environmental effects following unconfined release. The CFIA has therefore concluded that the potential impact on biodiversity of corn event MON 87419 is unlikely to be different from that of the corn varieties that are 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 corn event MON 87419, 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 corn event MON 87419 meet the definitions and requirements of feeds as listed in Schedule IV of the Feeds Regulations.

(i) Potential impact of corn event MON 87419 on livestock nutrition

Nutrient and anti-nutrient composition

The nutritional equivalence of corn event MON 87419 plants treated with dicamba and glufosinate-ammonium herbicides to those of the unmodified control corn variety was determined from five replicated field trial sites in the US during the 2013 growing season. Forage and grain samples were analysed for; moisture, ash, protein, crude fat, carbohydrates (by calculations), acid detergent fibre (ADF), neutral detergent fibre (NDF), calcium and phosphorus. Grain samples were further analysed for amino acids, total detergent fibre (TDF), fatty acids, vitamins, minerals, secondary metabolites (furfural, ferulic acid and p-coumaric acid) and anti-nutrients (phytic acid and raffinose) as recommended by the OECD consensus document for new varieties of corn [OECD, 2002 - PDF (208 kb)]. Corn compositional components were statistically analyzed using a mixed model analysis of variance, and statistical differences among treatments were identified and assessed (P<0.05). The biological relevance of any significant difference among corn varieties was assessed by determining the magnitude of difference between corn event MON 87419 and the unmodified control corn variety; assessment of the differences in the natural variation within the unmodified control corn variety across multiple sites and the natural variation within corn obtained from the published scientific literature and AFSI, 2011 database.

No statistically significant differences were observed between the unmodified control corn variety and corn event MON 87419 forage and grain for protein, fat, ash, carbohydrates, ADF, NDF, TDF(grain), calcium and phosphorus. All mean values of corn event MON 87419 were within the range of the values observed in the unmodified control corn variety and in the published scientific literature and AFSI, 2011 database. No statistically significant differences were observed between the unmodified control corn variety and corn event MON 87419 for amino acids, minerals (except manganese) vitamins and fatty acids analysed. All mean values of corn event MON 87419 were within the range of the values of the unmodified control corn variety and in the published scientific literature and AFSI, 2011 database. The mean value of manganese in corn event MON 87419 was statistically significantly higher than the level in the unmodified control corn variety; however the mean was within the range of the control values and published scientific literature. The secondary metabolites; ferulic acid and p-coumaric acid and the anti-nutrients; phytic acid and raffinose in corn event MON 87419 were not statistically significant different from the values for the unmodified control corn variety. All mean values of corn event MON 87419 were within the range of the values observed in the unmodified control corn variety; published scientific literature and AFSI, 2011 database. Furfural was not detected in corn event MON 87419 and the unmodified control corn variety.

Conclusion

It was concluded, based on the evidence provided by Monsanto Canada Inc., that the nutritional composition of corn event MON 87419 is similar to that of the unmodified corn control variety grown in the trials and to that reported for other corn in the published scientific literature. Feed ingredients derived from corn event MON 87419 are considered to meet present ingredient definitions for corn.

2. Potential impact of MON 87419 maize 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.

Corn event MON 87419 is tolerant to dicamba and glufosinate-ammonium herbicides due to production of the DMO and PAT (pat) proteins, respectively. A weight-of-evidence approach was used to assess the impacts of corn event MON 87419 on the following potential hazards relative to the safety of feed ingredients derived from this event:

Novel DMO protein

To obtain sufficient quantities of DMO protein for the evaluation of environmental and feed safety, it was necessary to express the dmo gene in a microbial production system. Equivalency was demonstrated between corn event MON 87419-produced DMO protein and E. coli-produced DMO protein that had been used in studies previously submitted by the petitioner for their cotton event MON 88701. These determinations of equivalency were based on similar molecular weights, immunoreactivities and tryptic peptide mass mapping results. Demonstration of equivalence between corn event MON 87419-produced DMO protein and E. coli-produced DMO protein used in studies submitted for MON88701 allows utilization of information from these studies to confirm the safety of the DMO protein produced in corn event MON 87419.

The potential allergenicity and toxicity of the DMO protein to livestock were evaluated. With respect to its potential allergenicity, no single experimental method yields decisive evidence, thus a weight-of-evidence approach was taken, taking into account information obtained with various test methods. The source of the dmo gene, S. maltophilia, is not known to produce allergens and a bioinformatics evaluation of the DMO protein amino acid sequences confirmed the lack of relevant similarities between this protein and known allergens. Bacterially produced DMO protein safety studies previously provided for assessment of corn event MON 87419 indicated that, unlike many allergens, this protein is rapidly degraded in simulated gastric fluid. The weight of evidence thus indicates that the DMO protein is unlikely to be allergenic.

In terms of the potential toxicity to livestock, the DMO protein lack a mode of action to suggest that it is intrinsically toxic to livestock and a bioinformatics evaluation of its protein amino acid sequences confirmed the lack of relevant similarities between the DMO protein and known toxins. In addition, bacterially produced DMO protein safety studies previously provided for assessment of cotton event MON 88701 indicated that no adverse effects were observed when the DMO protein was ingested by mice at doses of approximately 283 mg/ kg body weight. This information indicates that the DMO protein is unlikely to be toxic to livestock.

The livestock exposure to the DMO protein is expected to be negligible as this protein is expressed at very low levels in corn event MON 87419 and are rapidly degraded under conditions which simulate the mammalian digestive tract.

Novel PAT protein

To obtain sufficient quantities of PAT protein for evaluation of environmental and feed safety, it was necessary to express the pat gene in an E. coli-production system. Equivalency was demonstrated between the corn event MON 87419-produced PAT protein and an E. coli-produced PAT protein by comparing their molecular weights, immunoreactivities, glycosylation patterns, tryptic peptide mass mapping results and functional activities. Based on the results, the proteins were found to be equivalent. Demonstration of equivalence between the PAT protein produced in E. coli and in corn event MON 87419 allows the PAT protein produced in E. coli to be used in studies to confirm the safety of the PAT protein produced in corn event MON 87419.

The potential allergenicity and toxicity of the PAT protein to livestock were evaluated. With respect to its potential allergenicity, no single experimental method yields decisive evidence, thus a weight-of-evidence approach was taken, taking into account information obtained with various test methods. The source of the pat gene, S. virdochromogenes, is not known to produce allergens and a bioinformatics evaluation of the PAT protein amino acid sequence confirmed the lack of relevant similarities between the PAT protein and known allergens. E. coli-produced PAT protein safety studies indicated that, unlike many allergens, this protein is rapidly degraded in simulated gastric fluid. The weight of evidence thus indicates that the PAT protein is unlikely to be allergenic.

In terms of its potential toxicity to livestock, the PAT protein lacks a mode of action to suggest that it is intrinsically toxic to livestock and a bioinformatics evaluation of the PAT protein amino acid sequence confirmed the lack of relevant similarities between the PAT protein and known toxins. In addition, E. coli-produced PAT protein safety studies indicated that no adverse effects were observed when the PAT protein was ingested by mice at doses of approximately 1086 mg/kg body weight. This information indicates that the PAT protein is unlikely to be toxic to livestock.

The livestock exposure to the PAT protein is expected to be negligible as the PAT protein is expressed at very low levels in corn event MON 87419 and is rapidly degraded under conditions which simulate the mammalian digestive tract.

Chemical pesticide residue profile

The herbicide residues and metabolites in feed commodities produced from corn event MON 87419, following application of herbicides, was also evaluated as part of the feed safety assessment.

It was determined that, under the proposed conditions of the use, potential glufosinate-ammonium residues and metabolites in livestock commodities derived from corn event MON 87419 and its by-products would not present levels of concern to livestock, nor humans via the potential transfer into foods of animal origin, based on current maximum residue limits (MRLs) as set by Health Canada's Pest Management Regulatory Agency (PMRA).

The restriction for the use in livestock feed of dicamba-treated forage and stover which was put in place with the authorization of this event (January 28, 2016) pending PMRA assessment, was removed effective October 4, 2019. The removal of the restriction was following an approval by the PMRA for dicamba application on corn event MON 87419. Therefore, it was determined that, under the proposed conditions of use, potential dicamba residues and metabolites in livestock commodities derived from corn event MON 87419 and its by-products would not present levels of concern to 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.

It was also determined that the potential total dicamba residues, including relevant metabolites, in corn event MON 87419 grain are below the MRL as set by the PMRA.

Conclusion

It was concluded, based on the evidence provided by Monsanto Canada ULC, from a toxicological view of point, that corn event MON 87419 is as safe as conventional corn varieties. Feed ingredients derived from corn event MON 87419 are considered to meet present ingredient definitions for corn in the Feeds Regulations and as such corn event MON 87419 is approved for use as livestock feed in Canada.

VI. New information requirements

If at any time, Monsanto Canada Inc. becomes aware of any new information regarding risk to the environment, livestock or human health, which could result from the unconfined environmental release or livestock feed use of corn event MON 87419 or lines derived from it, Monsanto Canada 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 corn event MON 87419 on the environment, livestock and human health and may re-evaluate its decision with respect to the livestock feed use and unconfined environmental release authorizations of corn event MON 87419.

VII. Regulatory decision

Based on the review of the data and information submitted by Monsanto Canada Inc. and input from other relevant scientific sources, the Plant and Biotechnology Risk Assessment Unit of the Plant Health Science Directorate, CFIA, has concluded that the unconfined environmental release of corn event MON 87419 does not present altered environmental risk when compared to corn varieties that are currently grown in Canada.

Based on the review of the data and information submitted by Monsanto Canada Inc. and input from other relevant scientific sources, the Animal Feed Division of the Animal Health Directorate, CFIA, has concluded that the novel DMO protein-based herbicide tolerance trait and the novel PAT protein-based herbicide tolerance trait will not confer to corn event MON 87419 any characteristic that would raise any concerns regarding the safety or nutrition of corn event MON 87419. Grain corn, its by-products and corn oil are currently listed in IV of the Feeds Regulations and are, therefore authorized for use in livestock feeds in Canada. Corn event MON 87419 has been found to be as safe as and as nutritious as currently and historically grown corn varieties. Corn event MON 87419 and its products are considered to meet present ingredient definitions and are authorized for use as livestock feed ingredients in Canada.

Unconfined release into the environment and use as livestock feed of corn event MON 87419 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, respectively, as of January 28, 2016. Any corn lines derived from the corn event MON 87419 may also be released into the environment and used as livestock feed, provided that:

  1. no inter-specific crosses are performed
  2. the intended use(s) are similar
  3. it is known based on characterization that these plants do not display any additional novel traits and are substantially equivalent to corn varieties that are currently grown and permitted to be used as livestock feed in Canada, in terms currently grown and permitted to be used as livestock feed in Canada, in terms of their potential environmental impact and livestock feed safety
  4. and the novel genes are expressed at levels similar to that of the authorized line

Corn event MON 87419 is subject to the same phytosanitary import requirements as unmodified corn varieties. Corn event MON 87419 must also meet the requirements of other Canadian legislation, including but not limited to the requirements set out in the Food and 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 corn event MON 87419.

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