97-1754. DeKalb Genetics Corporation; Pesticide Tolerance Petitions Filings  

  • [Federal Register Volume 62, Number 16 (Friday, January 24, 1997)]
    [Notices]
    [Pages 3682-3685]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 97-1754]
    
    
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    ENVIRONMENTAL PROTECTION AGENCY
    [PF-660; FRL-5380-2]
    
    
    DeKalb Genetics Corporation; Pesticide Tolerance Petitions 
    Filings
    
    AGENCY: Environmental Protection Agency (EPA).
    ACTION: Notice of filing.
    
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    SUMMARY: This notice announces the filing of pesticide petitions 
    proposing regulations establishing exemptions from the requirement of a 
    tolerance for residues of the active ingredient plant-pesticide 
    Bacillus thuringiensis subsp. kurstaki CrylA(c) protein and the genetic 
    material necessary for the production of this protein in or on all raw 
    agricultural commodities and the inert ingredient plant-pesticide 
    phosphinothricin acetyltransferase protein and the genetic material 
    necessary for the production of this protein in or on all raw 
    agricultural commodities. This notice includes a summary of the 
    petition that was prepared by the petitioner, DeKalb Genetics 
    Corporation.
    
    DATES: Comments, identified by the docket number PF-660, must be 
    received on or before February 24, 1997.
    
    ADDRESSES: By mail, submit written comments to: Public Response and 
    Program Resources Branch, Field Operations Division (7506C), Office of 
    Pesticide Programs, Environmental Protection Agency, 401 M St., SW., 
    Washington, DC 20460. In person, bring comments to: Rm. 1132, Crystal 
    Mall #2, 1921 Jefferson Davis Hwy., Arlington, VA.
        A record has been established for this notice document under docket 
    number PF-660 (including any comments and data submitted electronically 
    as described below). A public version of this record, including 
    printed, paper versions of electronic comments, which does not include 
    any information claimed as CBI, is available for inspection from 8:30 
    a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The 
    public record is located in the Public Response and Program Resources 
    Branch, Field Operations Division (7506C), Office of Pesticide 
    Programs, Environmental Protection Agency, Rm. 1132, Crystal Mall #2, 
    1921 Jefferson Davis Highway, Arlington, VA.
        Comments and data may also be submitted electronically by sending 
    electronic mail (e-mail) to: opp-docket@epamail.epa.gov or by 
    submitting disks. Electronic comments must be submitted either in ASCII 
    format (avoiding the use of special characters and any form of 
    encryption) or in WordPerfect in 5.1 file format. All comments and data 
    in electronic form must be identified by the docket number PF-660. 
    Electronic comments on this notice may be filed online at many Federal 
    Depository Libraries. The official record for this rulemaking, as well 
    as the public version described above, will be kept in paper form. 
    Accordingly, EPA will transfer all comments received electronically 
    into printed, paper form as they are received and will place the paper 
    copies in the official rulemaking record, which will also include all 
    comments submitted directly in writing.
        Information submitted as a comment concerning this notice may be 
    claimed confidential by marking any part or all of that information as 
    ``Confidential Business Information'' (CBI). Information so marked will 
    not be disclosed except in accordance with procedures set forth in 40 
    CFR part 2. No CBI should be submitted through e-mail. A copy of the 
    comment that does not contain CBI must be submitted for inclusion in 
    the public record. Information not marked confidential may be disclosed 
    publicly by EPA without prior notice.
    
    
    [[Page 3683]]
    
    
    FOR FURTHER INFORMATION CONTACT: Mike Mendelsohn, Biopesticides and 
    Pollution Prevention Division (7501W), Office of Pesticide Programs, 
    Environmental Protection Agency, 401 M St., SW., Washington, DC 20460. 
    Office location, telephone number, and e-mail address: 5th Floor, CS 
    B1, 2805 Jefferson Davis Hwy., Arlington, VA, 703-308-8715; e-mail: 
    mendelsohn.mike@epamail.epa.gov.
    
    SUPPLEMENTARY INFORMATION: EPA has received pesticide petitions (PP) 
    6E4710 and 6F4711 from DeKalb Genetics Corporation (Dekalb), 3100 
    Sycamore Road, DeKalb, IL 60115. The petitions propose, pursuant to 
    section 408 of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 
    U.S.C. 346a, to amend 40 CFR part 180 to establish exemptions from the 
    requirement of a tolerance for the plant-pesticides Bacillus 
    thuringiensis subsp. kurstaki CrylA(c) protein and the genetic material 
    necessary for the production of this protein in or on all raw 
    agricultural commodities and phosphinothricin acetyltransferase protein 
    and the genetic material necessary for the production of this protein 
    in or on all raw agricultural commodities. EPA has determined that the 
    petition contains data or information regarding the elements set forth 
    in section 408(d)(2); however, EPA has not fully evaluated the 
    sufficiency of the submitted data at this time or whether the data 
    supports granting of the petition. Additional data may be needed before 
    EPA rules on the petition.
        Dekalb has stated that analytical methods for the detection and 
    measurement of the CryIA(c) and PAT proteins are not needed since they 
    are petitioning for exemptions from the requirement of a tolerance on 
    the basis of mammalian safety.
        As required by section 408(d) of the FFDCA, as recently amended by 
    the Food Quality Protection Act, Dekalb included in the petition a 
    summary of the petition and authorization for the summary to be 
    published in the Federal Register in a notice of receipt of the 
    petition. The summary represents the views of Dekalb; EPA, as mentioned 
    above, is in the process of evaluating the petition. As required by 
    section 408(d)(3) EPA is including the summary as a part of this notice 
    of filing. EPA may have made minor edits to the summary for the purpose 
    of clarity.
    
    I. Petition Summary for PP 6F4711
    
        This unit summarizes information cited by DeKalb to support the 
    proposed tolerance exemption for Bacillus thuringiensis subsp. kurstaki 
    CryIA(c) protein and the genetic material necessary for the production 
    of this protein in or on all raw agricultural commodities when used as 
    a plant-pesticide active ingredient.
    
    A. Bacillus thuringiensis subsp. kurstaki CryIA(c) Protein Uses
    
        Corn, Zea mays L., has been genetically engineered to be resistant 
    to Lepidopteran insect pests. Insect protection was accomplished by 
    insertion of the cryIA(c) gene from Bacillus thuringiensis subsp. 
    kurstaki which encodes a protein that is specifically insecticidal to 
    Lepidopteran insect larvae but Dekalb believes is safe to nontarget 
    organisms such as mammals, birds, fish, and nontarget insects. CryIA(c) 
    protein is used as a ``plant-pesticide'' in transgenic corn plants to 
    control Lepidopteran insects including European corn borer. CryIA(c) 
    corn will be deployed in situations where Lepidopteran insect control 
    is important.
    
    B. Product Identity and Chemistry
    
        Product analysis data demonstrated that microbially expressed and 
    purified CryIA(c) delta endotoxin used for mammalian toxicological 
    testing purposes is not significantly different than the delta 
    endotoxin expressed in the plant. The following assays were used to 
    determine the similarity of the microbially expressed and purified 
    CryIA(c) delta endotoxin and that produced in corn: SDS-PAGE, Western 
    blots, amino acid sequencing, testing for post translational 
    modification, and insect bioactivity. These assays demonstrated that 
    the truncated CryIA(c) delta endotoxin expressed in corn and the 
    tryptic core of the microbially-produced CryIA(c) endotoxin are 
    similar.
    
    C. Mammalian Toxicological Profile
    
        The CryIA(c) protein produced in transgenic corn is the tryptic 
    core of CryIA(c) found in nature and used in Bacillus thuringiensis 
    susp. kurstaki microbial formulations that have been registered with 
    the EPA and have been commercially available for over 30 years. To be 
    active against the target insect, CryIA(c) protein must be ingested. In 
    the insect gut, the protein binds to specific receptors in the insect 
    mid-gut, inserts into the membrane and forms ion-specific pores. These 
    events disrupt the digestive processes and cause the death of the 
    insect. There are no receptors for the protein delta endotoxins of 
    Bacillus thuringiensis subspecies on the surface of mammalian 
    intestinal cells; therefore humans are not susceptible to these 
    proteins.
        The mammalian toxicological data submitted in support of the 
    exemption from the requirement for a tolerance include an acute oral 
    toxicity study with mice and a test for digestibility under simulated 
    gastric conditions. The results of these studies demonstrate that 
    CryIA(c) protein has an acute LD50 greater than 3,325 mg/kg. In 
    tests for digestibility in simulated gastric fluid, CryIA(c) protein 
    was found to degrade to below detectable levels within a few seconds 
    when exposed to full strength gastric fluid. When exposed to simulated 
    gastric fluid that had been diluted 100-fold, CryIA(c) protein degraded 
    to below detectable levels in five minutes. Given the rapid 
    digestibility of CryIA(c) delta endotoxin, no chronic effects are 
    expected. CryIA(c) delta endotoxin, or metabolites of the endotoxin are 
    not known to, or expected to have any effect on the immune or endocrine 
    systems. Proteins in general are not carcinogenic, therefore, no 
    carcinogenic risk is associated with the CryIA(c) protein.
        Current scientific knowledge suggests that common food allergens 
    tend to be resistant to degradation by heat, acid, and proteases and 
    are glycosylated and present at high concentrations in food. CryIA(c) 
    delta endotoxin is rapidly degraded by simulated gastric fluid, is not 
    present as a major component in food, and is apparently nonglycosylated 
    or otherwise post-translationally modified when produced in plants. 
    Despite decades of widespread use of Bacillus thuringiensis as a 
    pesticide (it has been registered since 1961), there have been no 
    confirmed reports of immediate or delayed allergic reactions to the 
    delta endotoxins despite significant oral, dermal, and inhalation 
    exposure to microbial products containing the delta endotoxins.
        The genetic material necessary for the production of Bacillus 
    thruringiensis CryIA(c) delta endotoxin are nucleic acids (DNA) which 
    comprise the genetic material encoding the CryIA(c) delta endotoxin and 
    the regulatory regions associated with the gene. Regulatory regions are 
    the genetic material that control the expression of the genetic 
    material encoding the CryIA(c) delta endotoxin, such as promoters, 
    terminators, introns, and enhancers. DNA is common to all forms of 
    plant and animal life, and there are no known instances of where 
    nucleic acids have been associated with toxic effects related to their 
    consumption. The nucleic acids introduced into CryIA(c) corn have been 
    characterized. No mammalian toxicity is expected from dietary exposure 
    to the genetic material necessary for the production of the
    
    [[Page 3684]]
    
    Bacillus thuringiensis CryIA(c) endotoxin in corn.
    
    D. Aggregate Exposure
    
        Exposure via dermal exposure or inhalation is unlikely given that 
    the delta endotoxin is contained in plant cells. Transfer of the 
    pesticide to drinking water is highly unlikely given that CryIA(c) 
    protein has been shown to degrade in senescing corn plants and Bt 
    proteins are known to rapidly degrade in the soil. Oral exposure, at 
    very low levels, may occur from ingestion of processed corn products 
    however the lack of mammalian toxicity, and the digestibility of the 
    protein have been demonstrated.
    
    E. Cumulative Exposure
    
        Consideration of a common mode of toxicity is not appropriate given 
    that there is no indication of mammalian toxicity of CryIA(c) protein 
    and no information that indicates that toxic effects would be 
    cumulative with any other compounds.
    
    F. Safety Determination
    
        1. U.S. population in general. The lack of acute toxicity and the 
    rapid digestibility of CryIA(c) delta endotoxin provides evidence for 
    the lack of toxicity and allergenicty and Dekalb believes support an 
    exemption from the requirement for a tolerance for Bacillus 
    thuringiensis subsp. kurstaki CryIA(c) protein. Bacillus thuringiensis 
    subsp. kurstaki delta endotoxins have been used in microbial 
    insecticide formulations that have been registered by the EPA and 
    commercially available since the early 1960s.
        2. Infants and children. The use sites for CryIA(c) delta endotoxin 
    are all agricultural for control of Lepidopteran insects. Therefore, 
    nondietary exposure to infants and children is not expected. Dekalb 
    believes that the lack of toxicity of CryIA(c) delta endotoxin and 
    history of safe use of Bacillus thruringiensis subsp. kurstaki delta 
    endotoxins provides reasonable certainty that no harm will result to 
    infants and children from aggregate dietary exposure to residues of 
    CryIA(c).
    
    G. Existing Tolerances or Tolerance Exemptions
    
        An exemption from the requirement for a tolerance was granted by 
    the EPA for ``Plant-pesticide Bacillus thuringiensis CryIA(c) Delta-
    Endotoxin and the Genetic Material Necessary for Its Production in 
    Cotton,'' Federal Register: September 15, 1995, (60 FR 47871; FRL-4976-
    9).
    
    II. Petition Summary for PP 6E4710
    
        This unit summarizes information cited by DeKalb to support the 
    proposed tolerance exemption for phosphinothricin acetyltransferase 
    protein and the genetic material necessary for the production of this 
    protein in or on all raw agricultural commodities when used as a plant-
    pesticide inert ingredient.
    
    A. Phosphinothricin Acetyltransferase Protein Uses
    
        Phosphinothricin acetyltransferase or PAT protein, is used as 
    ``plant-pesticide inert ingredient'' in transgenic, insect protected 
    corn plants. PAT functions as a selectable marker and as well as a 
    source of resistance to glufosinate herbicides. PAT protein is encoded 
    by the bar gene, originally cloned from a common soil bacterium, 
    Streptomyces hygroscopicus. Insect protected corn will be deployed in 
    situations where Lepidopteran insect control is important.
    
    B. Product Identity and Chemistry
    
        Product analysis data demonstrated that microbially expressed and 
    purified PAT protein used for mammalian toxicological testing purposes 
    is not significantly different than the PAT protein expressed in the 
    plant. The following assays were used to determine the similarity of 
    the microbially expressed and purified PAT protein and that produced in 
    corn: SDS-PAGE,Western blots, amino acid sequencing and testing for 
    post translational modification. These assays demonstrated that the PAT 
    protein expressed in corn and PAT protein produced in and purified from 
    a microbial source are similar.
    
    C. Mammalian Toxicological Profile
    
        The PAT enzyme catalyzes the transfer of an acetyl group from 
    acetyl CoA to the amino group of phosphinothricin (also known as 
    glufosinate). The enzyme is highly substrate specific. Dekalb believes 
    it is therefore highly unlikely that PAT will acetylate any naturally 
    occurring compound in maize cells.
        The mammalian toxicological data submitted in support of the 
    exemption from the requirement for a tolerance include an acute oral 
    toxicity study with mice and a test for digestibility under simulated 
    gastric conditions. The results of these studies demonstrate that PAT 
    protein has an acute LD50 greater than 2,500 mg/kg. In tests for 
    digestibility in simulated gastric fluid, PAT protein was found to 
    degrade to below detectable levels within 2 minutes when exposed to 
    full strength gastric fluid. When exposed to simulated gastric fluid 
    that had been diluted 100-fold, PAT protein degraded to below 
    detectable levels in 5 minutes. Given the rapid digestibility of PAT 
    protein, no chronic effects are expected. PAT protein or metabolites 
    protein are not known to, or expected to have any effect on the immune 
    or endocrine systems. Proteins in general are not carcinogenic, 
    therefore, no carcinogenic risk is associated with the PAT protein.
        Current scientific knowledge suggests that common food allergens 
    tend to be resistant to degradation by heat, acid, and proteases and 
    are glycosylated and present at high concentrations in food. PAT 
    protein is rapidly degraded by simulated gastric fluid, is not present 
    as a major component in food, and is apparently nonglycosylated or 
    otherwise post-translationally modified when produced in plants.
        The genetic material necessary for the production of PAT protein 
    are nucleic acids (DNA) which comprise the genetic material encoding 
    the PAT protein and the regulatory regions associated with the gene. 
    Regulatory regions are the genetic material that control the expression 
    of the genetic material encoding the PAT protein, such as promoters, 
    terminators, introns, and enhancers. DNA is common to all forms of 
    plant and animal life, and there are no known instances of where 
    nucleic acids have been associated with toxic effects related to their 
    consumption. The nucleic acids introduced into insect protected corn 
    have been characterized. No mammalian toxicity is expected from dietary 
    exposure to the genetic material necessary for the production of the 
    PAT protein in corn.
    
    D. Aggregate Exposure
    
        Exposure via dermal exposure or inhalation is unlikely given that 
    the PAT protein is contained in plant cells. Transfer of the pesticide 
    to drinking water is highly unlikely given that PAT protein is 
    undetectable in pollen, has been shown to degrade in senescing corn 
    plants. Oral exposure, at very low levels, may occur from ingestion of 
    processed corn products; however, Dekalb believes that the lack of 
    mammalian toxicity, and the digestibility of the protein have been 
    demonstrated.
    
    E. Cumulative Exposure
    
        Dekalb believes that consideration of a common mode of toxicity is 
    not appropriate given that there is no indication of mammalian toxicity 
    of PAT protein and no information that indicates that toxic effects 
    would be cumulative with any other compounds.
    
    [[Page 3685]]
    
    F. Safety Determination
    
        1. U.S. population in general. Dekalb believes that the lack of 
    acute toxicity and the rapid digestibility of PAT protein provide 
    evidence for the lack of toxicity and allergenicty and support an 
    exemption from the requirement for a tolerance for PAT protein.
        2. Infants and children. The use sites for insect protected corn 
    containing PAT protein are all agricultural for control of Lepidopteran 
    insects. Therefore, nondietary exposure to infants and children is not 
    expected. Dekalb believes that the lack of toxicity of PAT protein 
    provides reasonable certainty that no harm will result to infants and 
    children from aggregate dietary exposure to residues of PAT.
    
    G. Existing Tolerances or Tolerance Exemptions
    
        An exemption from the requirement for a tolerance was granted by 
    the EPA for ``Plant-pesticide Inert Ingredient Phosphinothricin 
    Acetyltransferase (PAT) and the Genetic Material Necessary for Its 
    Production (Plasmid Vector pCIBP3064) in Corn,'' Federal Register: 
    August 16, 1995, (60 FR 42450; FRL-4971-2).
    
    III. Administrative Matters
    
        EPA invites interested persons to submit comments on this notice of 
    filing. Comments must bear a notification indicating the document 
    control number [PF-660]. All written comments filed in response to this 
    petition will be available in the Public Response and Program Resources 
    Branch, at the address given above from 8:30 a.m. to 4 p.m., Monday 
    through Fridy, except legal holidays.
        A record has been established for this notice under docket number 
    [PF-660] (including comments and data submitted electronically as 
    described below). A public version of this record, including printed, 
    paper versions of electronic comments, which does not include any 
    information claimed as CBI, is available for inspection from 8:30 a.m. 
    to 4 p.m., Monday through Friday, excluding legal holidays. The public 
    record is located in Rm. 1132 of the Public Response and Program 
    Resources Branch, Field Operations Division (7506C), Office of 
    Pesticide Programs, Environmental Protection Agency, Crystal Mall #2, 
    1921 Jefferson Davis Highway, Arlington, VA.
        Electronic comments can be sent directly to EPA at:
        opp-docket@epamail.epa.gov
    
        Electronic comments must be submitted as an ASCII file avoiding the 
    use of special characters and any form of encryption.
        The official record for this rulemaking, as well as the public 
    version, as described above will be kept in paper form. Accordingly, 
    EPA will transfer all comments received electronically into printed, 
    paper form as they are received and will place the paper copies in the 
    official rulemaking record which will also include all comments 
    submitted directly in writing. The official rulemaking record is the 
    paper record maintained at the address in ``ADDRESSES'' at the 
    beginning of this document.
    
        Authority: 21 U.S.C. 346a.
    
    List of Subjects
    
        Environmental protection, Agricultural commodities, Pesticides and 
    pests, Reporting and recordkeeping.
    
        Dated: January 17, 1997.
    
    Flora Chow,
    
    Acting Director, Biopesticides and Pollution Prevention Division, 
    Office of Pesticide Programs.
    
    [FR Doc. 97-1754 Filed 1-23-97; 8:45 am]
    BILLING CODE 6560-50-F
    
    
    

Document Information

Published:
01/24/1997
Department:
Environmental Protection Agency
Entry Type:
Notice
Action:
Notice of filing.
Document Number:
97-1754
Dates:
Comments, identified by the docket number PF-660, must be received on or before February 24, 1997.
Pages:
3682-3685 (4 pages)
Docket Numbers:
PF-660, FRL-5380-2
PDF File:
97-1754.pdf