[Federal Register Volume 62, Number 197 (Friday, October 10, 1997)]
[Notices]
[Pages 52998-53001]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-27012]


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ENVIRONMENTAL PROTECTION AGENCY

[PF-768; FRL-5748-5]


Notice of Filing of Pesticide Petitions

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice.

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SUMMARY: This notice announces the filing of a pesticide petition 
proposing a regulation establishing an exemption from the requirement 
for a tolerance for residues of Bacillus thuringiensis Cry1, Cry2 and 
Cry3 classes of proteins and the genetic material necessary for the 
production of these proteins in or on all raw agricultural commodities. 
This notice includes a summary of the petition that was prepared by the 
petitioner, Monsanto Company.
DATES: Comments, identified by the docket control number PF-768, must 
be received on or before November 10, 1997.
ADDRESSES: By mail submit written comments to: Public Information and 
Records Integrity Branch (7506C), Information Resources and Services 
Division, Office of Pesticides Programs, Environmental Protection 
Agency, 401 M St., SW., Washington, DC 20460. In person bring comments 
to: Rm. 1132, CM #2, 1921 Jefferson Davis Highway, Arlington, VA.
    Comments and data may also be submitted electronically to: opp-
[email protected]. Follow the instructions under ``SUPPLEMENTARY 
INFORMATION.'' No confidential business information should be submitted 
through e-mail.
    Information submitted as a comment concerning this document may be 
claimed confidential by marking any part or all of that information as 
``Confidential Business Information'' (CBI). CBI should not be 
submitted through e-mail. Information marked as CBI will not be 
disclosed except in accordance with procedures set forth in 40 CFR part 
2. 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. All written 
comments will be available for public inspection in Rm. 1132 at the 
address given above, from 8:30 a.m. to 4 p.m., Monday through Friday, 
excluding legal holidays.

FOR FURTHER INFORMATION CONTACT: Mike Mendelsohn, Biopesticides and 
Pollution Prevention Division (7501W), Office of Pesticide Programs, 
U.S. Environmental Protection Agency, 401 M St., SW., Washington, DC 
20460. Office location and telephone number: 5th floor CS #1, 2800 
Crystal Drive, Arlington, VA 22202, Telephone No. 703-308-8715, e-mail: 
[email protected].
SUPPLEMENTARY INFORMATION: EPA has received pesticide petitions as 
follows proposing the establishment and/or amendment of regulations for 
residues of certain pesticide chemicals in or on various food 
commodities under section 408 of the Federal Food, Drug, and Comestic 
Act (FFDCA), 21 U.S.C. 346a. EPA has determined that these petitions 
contain 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.
    The official record for this notice of filing, as well as the 
public version, has been established for this notice of filing under 
docket control number [PF-768] (including comments and data

[[Page 52999]]

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 official record is located at the address in 
``ADDRESSES'' at the beginning of this document.
    Electronic comments can be sent directly to EPA at:
    [email protected]


    Electronic comments must be submitted as an ASCII file avoiding the 
use of special characters and any form of encryption. Comment and data 
will also be accepted on disks in Wordperfect 5.1 file format or ASCII 
file format. All comments and data in electronic form must be 
identified by the docket number [PF-768] and appropriate petition 
number. Electronic comments on this notice may be filed online at many 
Federal Depository Libraries.

List of Subjects

    Environmental protection, Agricultural commodities, Food additives, 
Feed additives, Pesticides and pests, Reporting and recordkeeping 
requirements.

    Dated: September 29, 1997.

Janet L. Andersen,

Director, Biopesticides and Pollution Prevention Division, Office of 
Pesticide Programs

Summaries of Petitions

    Petitioner summaries of the pesticide petitions are printed below 
as required by section 408(d)(3) of the FFDCA. The summaries of the 
petitions were prepared by the petitioners and represent the views of 
the petitioners. EPA is publishing the petition summaries verbatim 
without editing them in any way. The petition summary announces the 
availability of a description of the analytical methods available to 
EPA for the detection and measurement of the pesticide chemical 
residues or an explanation of why no such method is needed.

Monsanto Company

PP 7F4888

    EPA has received a pesticide petition (PP 7F4888) from the Monsanto 
Company, 700 Chesterfield Parkway, North, St. Louis, MO 63198. The 
petition proposes, pursuant to section 408 of the Federal Food, Drug 
and Cosmetic Act, 21 U.S.C. section 346a (d), to amend 40 CFR part 180 
by establishing an exemption from the requirement for a tolerance for 
residues of the plant pesticides consisting of Bacillus thuringiensis 
Cry1, Cry2, and Cry3 classes of proteins and the genetic material 
necessary for the production of these proteins 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.
    Monsanto has stated that analytical methods of detection and 
measurement of the Cry1, Cry2, and Cry3 classes of proteins are not 
needed since they are petitioning for exemptions from the requirement 
for 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, Monsanto 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 Monsanto; 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.
    This unit summarizes information cited by Monsanto Company to 
support the proposed tolerance exemption for Bacillus thuringiensis 
Cry1, Cry2, and Cry3 classes of proteins and the genetic material 
necessary for the production of these proteins when used as plant-
pesticide active ingredients.

A. Bacillus thuringiensis Cry1, Cry2, and Cry3 Protein Uses

    The Environmental Protection Agency (EPA) has approved the 
commercial use of the Bacillus thuringiensis Cry1Ab, Cry1Ac, and Cry3A 
proteins as expressed in genetically engineered corn, cotton, and 
potato, respectively. The Agency has concluded that these Cry protein 
plant pesticides pose no foreseeable risks to human health and has 
granted exemptions from the requirement of a tolerance for these 
substances. A Cry2Aa plant pesticide is currently under review at EPA.
    The first Bacillus thuringiensis Cry protein exemptions from 
tolerance were limited to a specific Cry protein as expressed in a 
single crop, such as Cry3A in potato and Cry1Ac in cotton. More 
recently, in approving Monsanto's Cry1Ab expressed in corn (61 FR 
40340, August 2, 1996) and Dekalb's Cry1Ac expressed in corn (62 FR 
17720, April 11, 1997), EPA established a broad tolerance exemption for 
Cry1Ab and Cry1Ac proteins, respectively, in or on all plant raw 
agricultural commodities.
    In the future, many Bacillus thuringiensis Cry proteins are 
expected to be expressed in a wide variety of plants for insect 
protection. This petition provides the scientific bases for the generic 
human health safety determination that Cry1, Cry2, and Cry3 classes of 
proteins as expressed in plants pose no foreseeable human health risks. 
Accordingly, all Bacillus thuringiensis Cry1, Cry2, and Cry3 proteins 
as expressed in plants are proposed to be exempt from the requirement 
for a tolerance.

B. Product Identity and Chemistry

    Bacillus thuringiensis Cry proteins are named according to their 
similarity to established holotype proteins. Cry proteins with similar 
amino acid sequences are grouped together. Cry proteins with the same 
Arabic numeral (e.g., Cry1) share at least a 45 percent amino acid 
sequence identity. Those with the same Arabic numeral and upper case 
letter (e.g., Cry1A) share at least a 75 percent sequence identity. The 
same Arabic numeral and upper and lower case letter (e.g., Cry1Ab) 
designates a greater than 95 percent sequence identity. Therefore, one 
of the principal scientific rationales for this petition is that it 
applies safety conclusions from testing one or a few representative Cry 
proteins to a broader, but closely related, group of proteins proteins 
that by definition share significant amino acid sequence identity.
    To qualify for an exemption from tolerance, amino acid sequence 
analysis data must be provided to verify that the protein has been 
correctly classified as belonging to one of the ``exempt'' classes of 
Cry proteins (i.e., Cry1, Cry2, or Cry3). It should also be confirmed 
that the Cry protein exhibits no significant amino acid sequence 
homology with known food allergens based on a comparison with sequences 
contained in public domain databases. Information concerning the 
Bacillus thuringiensis holotype protein nomenclature and a continuously 
updated database of Bacillus thuringiensis holotype proteins can be 
found on the world wide web at http://epunix.biols.susx.ac.uk/Home/
Neil_Crickmore/Bt/holo.html.
    To ensure that this petition has broad applicability, it covers 
Bacillus

[[Page 53000]]

thuringiensis Cry proteins that are naturally occurring or that have 
been genetically modified by deletion, substitution, and/or insertion 
of amino acid sequences, provided that the protein exhibits at least 45 
percent amino acid sequence identity with a Cry protein from an 
``exempt'' class of Cry protein. If the protein has been modified by 
the insertion of amino acids from a non-exempt source (e.g., a source 
other than a Cry1, Cry2 or Cry3 protein), those inserted amino acid 
sequences may comprise no greater than five percent of the total amino 
acid sequence of the Cry protein.

C. Mammalian Toxicological Profile

    There currently exists an extensive body of scientific data 
demonstrating the safety of Cry proteins. A review of the literature 
establishes that many different Cry proteins have been evaluated in a 
variety of mammalian toxicology tests over the past 35 years. No 
adverse effects have been observed in mammals upon oral exposure to any 
of these Cry proteins.
    Oral dietary exposure is the only significant route by which humans 
can be exposed to Cry protein plant pesticides. Dermal and inhalation 
exposures are anticipated to be negligible because Cry proteins are 
produced within the plant, are not exuded, and are not volatile. To 
assess the implications of human dietary exposure to Bacillus 
thuringiensis Cry proteins, EPA has asked registrants to submit results 
of an acute oral mammalian toxicology study (oral LD50) and 
an in vitro digestibility study. These tests have been conducted using 
a microbially produced Bacillus thuringiensis protein that has been 
shown to be equivalent to the plant-expressed protein.
    No treatment-related adverse effects have been observed in any of 
the acute oral mammalian toxicity studies conducted with microbially 
produced Cry1Ab, Cry1Ac, Cry2A, and Cry3A proteins. Six oral gavage 
studies in mice established the LD50 to be >3,280 mg/kg to 
>5,200 mg/kg for these proteins. Based on these results there is a 
safety factor of greater than 50,000 for human dietary exposure to 
Cry1Ab and Cry1Ac proteins in corn or cottonseed, greater than one 
million for Cry3A protein in potato, and greater than two million for 
Cry1Ac protein in tomato. Because all of the testing of Bacillus 
thuringiensis plant pesticides has yielded negative results, no further 
mammalian toxicology testing (beyond acute and digestibility studies) 
has been required to support registration and exemptions from 
tolerance.
    The no observed effect level (NOEL) for Cry1Ab was > 0.45 mg/kg/day 
in a 28-day repeated dose oral toxicity study in mice and > 0.06 mg/kg/
day in a 31-day repeated dose study in rabbits. Treatment doses in the 
28-day and 31-day studies were estimated to be 1,000 to 4,000 times the 
maximum anticipated human exposure from consuming tomatoes genetically 
engineered to produce Cry1Ab (Noteborn et al. Food Safety of Transgenic 
Tomatoes Expressing the Insecticidal Crystal Protein Cry1Ab from 
Bacillus thuringiensis and the Marker Enzyme APH(3') II. Med. Fac. 
Landbouww. Univ. Gent, 58/4b, 1993). Based on the lack of toxic effects 
and the large margins of safety for both acute and 30-day exposures, 
these Cry proteins pose no foreseeable risks to human health. Moreover, 
these proteins are unlikely to cause endocrine effects because they 
exhibit no structural or functional similarity to estrogen or estrogen-
mimic compounds.
    EPA has stated that when proteins are toxic, they are known to act 
via acute mechanisms and at very low dose levels (Sjoblad et al. 
``Toxicological Considerations for Protein Components of Biological 
Pesticide Products,'' Regulatory Toxicology and Pharmacology, 15:3-9, 
1992). The Cry proteins tested so far are judged to be nontoxic to 
mammals. Monsanto believes that the acute toxicity data on these 
representative Cry proteins and the extensive data base on microbial 
Bacillus thuringiensis products supports a broader conclusion: All Cry 
proteins classified by their amino acid sequence to be Cry1, Cry2, or 
Cry3 are highly unlikely to be toxic to humans.
    In the future, crops may be modified to express significantly 
higher levels of Cry proteins than are expressed in the currently 
commercialized varieties. This does not alter the favorable safety 
conclusions for Cry proteins. The existing toxicology studies, showing 
no effects at the limit dose, would still support the exemption from 
the requirement for a tolerance and the conclusion that a tolerance is 
not necessary to protect human health.
    Further scientific evidence for the safety of Cry proteins is that 
they have been shown to be rapidly degraded under conditions simulating 
the human gastrointestinal tract. Results of seven in vitro assays 
conducted with representative Cry1, Cry2, and Cry3 proteins indicate 
that the proteins are rapidly degraded, usually within 30 seconds. 
These results support the broader conclusion that members of these 
groups of Cry proteins (that share significant amino acid sequence 
identity) are likely to be rapidly degraded following ingestion by 
humans.
    The demonstrated rapid degradation of Cry protein following 
ingestion minimizes the potential for an allergenic reaction. By 
comparison, food allergens generally persisted in the gastrointestinal 
model, whereas common food proteins with no allergenic history degraded 
rapidly in simulated gastric fluid (Metcalfe et al. ``Assessment of the 
Allergenic Potential of Foods Derived from Genetically Engineered Crop 
Plants,''Critical Rev. in Food Science and Nutrition, 36(s):S165-S186, 
1996). Searches of allergen sequence databases have shown no 
significant matches with the Cry proteins. Cry proteins do not share 
characteristics often exhibited by known food allergens. Unlike many 
known food allergens, the Cry proteins as expressed in plants are 
present in relatively low concentrations, and are heat labile. In 
addition, in the greater than 30 year history of commercial use, there 
have been no reported cases of allergenic reactions to the microbial 
Bacillus thuringiensis products (61 FR 40430, August 2, 1996).
    Results of testing microbial Bacillus thuringiensis preparations 
for oral mammalian toxicity over the past 35 years demonstrate the 
total lack of acute, subchronic, and chronic oral toxicity associated 
with Bacillus thuringiensis microbial pesticides. These findings are 
directly relevant to this petition because these microbial preparations 
contain genes encoded for the production of at least four different 
classes of Cry proteins, including seven Cry1 proteins and two each of 
the Cry2, and Cry3 proteins.
    Bacillus thuringiensis microbial products were first registered in 
1961 and have been applied continuously since then for an expanding 
number of uses in agriculture, disease vector control, and forestry. No 
reports of adverse effects have involved or implicated Cry proteins as 
the causative agent, nor have any of these effects been considered 
significant in view of the quality assurance safeguards that are in 
place for microbial products. Moreover, in establishing the existing 
tolerance exemptions for Cry protein plant pesticides, EPA has stated 
that FIFRA section 6(a)2 reports claiming allergic reactions ``were not 
due to Bacillus thuringiensis itself or any of the Cry toxins.''
    The genetic material necessary for the production of Bacillus 
thuringiensis Cry proteins are nucleic acids (DNA) which comprise the 
genetic material encoding the proteins and the regulatory regions

[[Page 53001]]

associated with the genes. Regulatory regions are the genetic material 
that control the expression of the genetic material encoding the Cry 
proteins, 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. No mammalian toxicity is expected 
from dietary exposure to the genetic material necessary for the 
production of any Bacillus thuringiensis proteins, including the Cry1, 
Cry2, and Cry3 classes of proteins. EPA has also proposed an exemption 
from the requirement for a tolerance for residues of nucleic acids 
produced in plants as part of a plant pesticide active ingredient (59 
FR 60542, November 23, 1994).

D. Aggregate Exposure

    Exposure to Cry1, Cry2, and Cry3 proteins via dermal exposure or 
inhalation is unlikely given that these plant pesticides are contained 
in the plant, are not exuded and are not volatile. Therefore, worker 
and bystander exposure resulting from plant pesticides will be 
negligible, and would be unlikely to add measurably to any worker or 
bystander exposure resulting from microbial or other Bacillus 
thuringiensis formulations. Movement of the plant pesticides to 
drinking water is highly unlikely given that Cry proteins are known to 
rapidly degrade in the soil.

E. Cumulative Exposure

    Consideration of a common mode of toxicity is not appropriate given 
that there is no indication of mammalian toxicity of Cry proteins in 
microbial or other formulations and no information that indicates that 
toxic effects would be cumulative with any other compounds. Mammals are 
not susceptible to Cry proteins. This may be explained, in part, by the 
fact that conditions required for the complex steps in the mode of 
action do not exist in mammals. As anticipated, immunocytochemical 
analyses of Cry1A have revealed no comparable binding sites in mammals. 
Monsanto is not aware of any other substances that may be related, via 
a common mechanism of toxicity, to the proteins that are the subject of 
the proposed exemption.

F. Safety Determination

    1. U.S. population in general. The lack of toxicity and the rapid 
digestibility of Cry proteins provides evidence for the lack of 
toxicity and allergenicty and supports an exemption from the 
requirement of a tolerance for the Bacillus thuringiensis Cry1, Cry2, 
and Cry3 classes of proteins. These proteins have been used in 
microbial insecticide formulations that have been registered by the EPA 
and commercially available since the early 1960s. Accordingly, the 
available information supports a finding that there is a reasonable 
certainty that no harm will result to the U.S. population in general 
form aggregate dietary exposure to the Cry1, Cry2, and Cry3 classes of 
proteins.
    2. Infants and Children. Bacillus thuringiensis Cry proteins are 
expressed in plants to protect the plant from insect damage. Therefore, 
nondietary exposure to infants and children is not expected. The lack 
of toxicity of Cry proteins and history of safe use of Bacillus 
thuringiensis microbial pesticides provides reasonable certainty that 
no harm will result to infants and children from aggregate dietary 
exposure to Cry1, Cry2, and Cry3 classes of proteins. Accordingly, 
there is no need to apply an additional safety factor for infants and 
children.

G. Existing Tolerances

    Exemptions from the requirement for a tolerance have been granted 
by EPA for Cry1Ab and Cry1Ac and the genetic material necessary for 
their production in all plant raw agricultural commodities (61 FR 
40340, August 2, 1996 and 62 FR 17720, April 11, 1997, respectively) 
and for Cry3A and the genetic material necessary for its production in 
potatoes (60 FR 21725, May 3, 1995).
[FR Doc. 97-27012 Filed 10-9-97; 8:45 am]
BILLING CODE 6560-50-F