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Aspergillus flavus AF36; Notice of Filing a Pesticide Petition to Establish an Exemption from a Tolerance for a Certain Pesticide Microbial Agent in or on Food

Note: EPA no longer updates this information, but it may be useful as a reference or resource.


 
[Federal Register: February 14, 2003 (Volume 68, Number 31)]
[Notices]
[Page 7554-7558]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr14fe03-90]

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ENVIRONMENTAL PROTECTION AGENCY
[OPP-2003-0020; FRL-7289-9]
 
Aspergillus flavus AF36; Notice of Filing a Pesticide Petition to 
Establish an Exemption from a Tolerance for a Certain Pesticide 
Microbial Agent in or on Food

AGENCY: Environmental Protection Agency (EPA).
ACTION: Notice.

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SUMMARY: This notice announces the initial filing of a pesticide 
petition proposing the establishment of regulations for residues of a 
certain pesticide microbial agent in or on various food commodities.

DATES: Comments, identified by docket ID number OPP-2003-0020, must be 
received on or before March 17, 2003.

ADDRESSES: Comments may be submitted electronically, by mail, or 
through hand delivery/courier. Follow the detailed instructions as 
provided in Unit I. of the SUPPLEMENTARY INFORMATION.

FOR FURTHER INFORMATION CONTACT: Shanaz Bacchus, Biopesticides and 
Pollution Prevention Division (7511C), Office of Pesticide Programs, 
Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460-0001; telephone number: (703) 308-8097; e-mail 
address: bacchus.shanaz@epa.gov.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    You may be potentially affected by this action if you are an 
agricultural producer, food manufacturer, or pesticide manufacturer. 
Potentially affected categories and entities may include, but are not 
limited to:
    ? Crop production (NAICS code 111)
    ? Animal production (NAICS code 112)
    ? Food manufacturing (NAICS code 311)
    ? Pesticide manufacturing (NAICS code 32532)
    This listing is not intended to be exhaustive, but rather provides 
a guide for readers regarding entities likely to be affected by this 
action. Other types of entities not listed in this unit could also be 
affected. The North American Industrial Classification System (NAICS) 
codes have been provided to assist you and others in determining 
whether this action might apply to certain entities. To determine 
whether you or your business may be affected by this action, you should 
carefully examine the applicability provisions. If you have any 
questions regarding the applicability of this action to a particular 
entity, consult the person listed under FOR FURTHER INFORMATION 
CONTACT.

B. How Can I Get Copies of this Document and Other Related Information?

    1. Docket. EPA has established an official public docket for this 
action under docket identification (ID) number OPP-2003-0020. The 
official public docket consists of the documents specifically 
referenced in this action, any public comments received, and other 
information related to this action. Although a part of the official 
docket, the public docket does not include Confidential Business 
Information (CBI) or other information whose disclosure is restricted 
by statute. The official public docket is the collection of materials 
that is available for public viewing at the Public Information and 
Records Integrity Branch (PIRIB), Rm. 119, Crystal Mall #2, 
1921 Jefferson Davis Hwy., Arlington, VA. This docket facility is open 
from 8:30 a.m. to 4 p.m., Monday through Friday, excluding legal 
holidays. The docket telephone number is (703) 305-5805.
    2. Electronic access. You may access this Federal Register document 
electronically through the EPA Internet under the ``Federal Register'' 
listings at http://www.epa.gov/fedrgstr/.
    An electronic version of the public docket is available through 
EPA's electronic public docket and comment system, EPA Dockets. You may 
use EPA Dockets at http://www.regulations.gov/ to submit or view public 
comments, access the index listing of the contents of the official 
public docket, and to access those documents in the public docket that 
are available electronically. Although not all docket materials may be 
available electronically, you may still access any of the publicly 
available docket materials through the docket facility identified in 
Unit I.B.1. Once in the system, select ``search,'' then key in the 
appropriate docket ID number.
    Certain types of information will not be placed in the EPA Dockets. 
Information claimed as CBI and other information whose disclosure is 
restricted by statute, which is not included in the official public 
docket, will not be available for public viewing in EPA's electronic 
public docket. EPA's policy is that copyrighted material will not be 
placed in EPA's electronic public docket but will be available only in 
printed, paper form in the official public docket. To the extent 
feasible, publicly

[[Page 7555]]

available docket materials will be made available in EPA's electronic 
public docket. When a document is selected from the index list in EPA 
Dockets, the system will identify whether the document is available for 
viewing in EPA's electronic public docket. Although not all docket 
materials may be available electronically, you may still access any of 
the publicly available docket materials through the docket facility 
identified in Unit I.B. EPA intends to work towards providing 
electronic access to all of the publicly available docket materials 
through EPA's electronic public docket.
    For public commenters, it is important to note that EPA's policy is 
that public comments, whether submitted electronically or in paper, 
will be made available for public viewing in EPA's electronic public 
docket as EPA receives them and without change, unless the comment 
contains copyrighted material, CBI, or other information whose 
disclosure is restricted by statute. When EPA identifies a comment 
containing copyrighted material, EPA will provide a reference to that 
material in the version of the comment that is placed in EPA's 
electronic public docket. The entire printed comment, including the 
copyrighted material, will be available in the public docket.
    Public comments submitted on computer disks that are mailed or 
delivered to the docket will be transferred to EPA's electronic public 
docket. Public comments that are mailed or delivered to the docket will 
be scanned and placed in EPA's electronic public docket. Where 
practical, physical objects will be photographed, and the photograph 
will be placed in EPA's electronic public docket along with a brief 
description written by the docket staff.

C. How and To Whom Do I Submit Comments?

    You may submit comments electronically, by mail, or through hand 
delivery/courier. To ensure proper receipt by EPA, identify the 
appropriate docket ID number in the subject line on the first page of 
your comment. Please ensure that your comments are submitted within the 
specified comment period. Comments received after the close of the 
comment period will be marked ``late.'' EPA is not required to consider 
these late comments. If you wish to submit CBI or information that is 
otherwise protected by statute, please follow the instructions in Unit 
I.D. Do not use EPA Dockets or e-mail to submit CBI or information 
protected by statute.
    1. Electronically. If you submit an electronic comment as 
prescribed in this unit, EPA recommends that you include your name, 
mailing address, and an e-mail address or other contact information in 
the body of your comment. Also include this contact information on the 
outside of any disk or CD ROM you submit, and in any cover letter 
accompanying the disk or CD ROM. This ensures that you can be 
identified as the submitter of the comment and allows EPA to contact 
you in case EPA cannot read your comment due to technical difficulties 
or needs further information on the substance of your comment. EPA's 
policy is that EPA will not edit your comment, and any identifying or 
contact information provided in the body of a comment will be included 
as part of the comment that is placed in the official public docket, 
and made available in EPA's electronic public docket. If EPA cannot 
read your comment due to technical difficulties and cannot contact you 
for clarification, EPA may not be able to consider your comment.
    i. EPA Dockets. Your use of EPA's electronic public docket to 
submit comments to EPA electronically is EPA's preferred method for 
receiving comments. Go directly to EPA Dockets at http://www.epa.gov/
edocket, and follow the online instructions for submitting comments. 
Once in the system, select ``search,'' and then key in docket ID number 
OPP-2003-0020. The system is an ``anonymous access'' system, which 
means EPA will not know your identity, e-mail address, or other contact 
information unless you provide it in the body of your comment.
    ii. E-mail. Comments may be sent by e-mail to opp-docket@epa.gov, 
Attention: Docket ID Number OPP-2003-0020. In contrast to EPA's 
electronic public docket, EPA's e-mail system is not an ``anonymous 
access'' system. If you send an e-mail comment directly to the docket 
without going through EPA's electronic public docket, EPA's e-mail 
system automatically captures your e-mail address. E-mail addresses 
that are automatically captured by EPA's e-mail system are included as 
part of the comment that is placed in the official public docket, and 
made available in EPA's electronic public docket.
    iii. Disk or CD ROM. You may submit comments on a disk or CD ROM 
that you mail to the mailing address identified in Unit I.C.2. These 
electronic submissions will be accepted in WordPerfect or ASCII file 
format. Avoid the use of special characters and any form of encryption.
    2. By mail. Send your comments to: Public Information and Records 
Integrity Branch (PIRIB) (7502C), Office of Pesticide Programs (OPP), 
Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460-0001, Attention: Docket ID Number OPP-2003-0020.
    3. By hand delivery or courier. Deliver your comments to: Public 
Information and Records Integrity Branch (PIRIB), Office of Pesticide 
Programs (OPP), Environmental Protection Agency, Rm. 119, Crystal Mall 
#2, 1921 Jefferson Davis Hwy., Arlington, VA, Attention: Docket 
ID Number OPP-2003-0020. Such deliveries are only accepted during the 
docket's normal hours of operation as identified in Unit I.B.1.

D. How Should I Submit CBI To the Agency?

    Do not submit information that you consider to be CBI 
electronically through EPA's electronic public docket or by e-mail. You 
may claim information that you submit to EPA as CBI by marking any part 
or all of that information as CBI (if you submit CBI on disk or CD ROM, 
mark the outside of the disk or CD ROM as CBI and then identify 
electronically within the disk or CD ROM the specific information that 
is CBI). Information so marked will not be disclosed except in 
accordance with procedures set forth in 40 CFR part 2.
    In addition to one complete version of the comment that includes 
any information claimed as CBI, a copy of the comment that does not 
contain the information claimed as CBI must be submitted for inclusion 
in the public docket and EPA's electronic public docket. If you submit 
the copy that does not contain CBI on disk or CD ROM, mark the outside 
of the disk or CD ROM clearly that it does not contain CBI. Information 
not marked as CBI will be included in the public docket and EPA's 
electronic public docket without prior notice. If you have any 
questions about CBI or the procedures for claiming CBI, please consult 
the person listed under FOR FURTHER INFORMATION CONTACT.

E. What Should I Consider as I Prepare My Comments for EPA?

    You may find the following suggestions helpful for preparing your 
comments:
    1. Explain your views as clearly as possible.
    2. Describe any assumptions that you used.
    3. Provide copies of any technical information and/or data you used 
that support your views.

[[Page 7556]]

    4. If you estimate potential burden or costs, explain how you 
arrived at the estimate that you provide.
    5. Provide specific examples to illustrate your concerns.
    6. Make sure to submit your comments by the deadline in this 
notice.
    7.To ensure proper receipt by EPA, be sure to identify the docket 
ID number assigned to this action in the subject line on the first page 
of your response. You may also provide the name, date, and Federal 
Register citation.

II. What Action is the Agency Taking?

    EPA has received a pesticide petition as follows proposing the 
establishment and/or amendment of regulations for residues of a certain 
pesticide chemical in or on various food commodities under section 408 
of the Federal Food, Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a. 
EPA has determined that this petition contains data or information 
regarding the elements set forth in FFDCA section 408(d)(2); however, 
EPA has not fully evaluated the sufficiency of the submitted data at 
this time or whether the data support granting of the petition. 
Additional data may be needed before EPA rules on the petition.

List of Subjects

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

    Dated: February 6, 2003.
 Phil Hutton,
Acting Director, Biopesticides and Pollution Prevention Division, 
Office of Pesticide Programs.

Summary of Petition

    The petitioner summary of the pesticide petition is printed below 
as required by FFDCA section 408(d)(3). The summary of the petition was 
prepared by the petitioner and represents the view of the petitioner. 
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.

Interregional Research Project Number 4 and The Arizona Cotton Research 
and Protection Council

PP 8E5001

    EPA has received a pesticide petition (PP 8E5001) from 
Interregional Research Project Number 4 (IR-4), New Jersey Agricultural 
Experiment Station, Technology Center, 681 U.S. Highway #1 
South, North Brunswick, NJ 08902-3390 on behalf of the Arizona Cotton 
Research and Protection Council, 3721 East Wier Avenue Phoenix, Arizona 
85040-2933 proposing pursuant to section 408(d) of the FFDCA, 21 U.S.C. 
346a(d), to amend 40 CFR 180.1206 by establishing an amendment/
expansion of an existing tolerance exemption for the microbial 
pesticide Aspergillus flavus AF36 in or on the food and feed commodity 
cotton and its by products.
    Pursuant to section 408(d)(2)(A)(i) of the FFDCA, as amended, the 
aforesaid Interregional Research Project Number 4 (IR-4), has submitted 
the following summary of information, data, and arguments in support of 
the pesticide petition on behalf of the Arizona Cotton Research and 
Protection Council, however EPA has not fully evaluated the merits of 
the pesticide petition. The summary may have been edited by EPA if the 
terminology used was unclear, the summary contained extraneous 
material, or the summary unintentionally made the reader conclude that 
the findings reflected EPA's position and not the position of the 
petitioner.

A. Product name and Proposed Use Practices

    Aspergillus flavus AF36, a non-aflatoxin-producing strain of 
Aspergillus flavus, is proposed for application to cotton to reduce the 
incidence of aflatoxin producing strains ofAspergillus flavus and 
thereby reduce aflatoxin contamination of cottonseed. When applied just 
prior to flowering, Aspergillus flavus AF36 which does not produce 
aflatoxin, competitively excludes aflatoxin producing Aspergillus 
flavus strains without increasing Aspergillus flavus in the environment 
in the long term. Sterile wheat seed colonized with Aspergillus flavus 
AF36 is applied at 10 lb of end-use product (total amount of active 
ingredient less than 0.01 lb/acre) per acre. The pesticide is currently 
being used in certain counties in the States of Arizona and Texas under 
an Experimental Use Permit (EPA Reg. No. 69224-EUP-1). The current 
submission proposes to establish a permanent exemption from tolerance 
for residues of Aspergillus flavus AF36 on cotton and its byproducts.

B. Product Identity/Chemistry

    1. Identity of the pesticide and corresponding residues. The 
pesticide and corresponding residues are identified as Aspergillus 
flavus AF36, a non-aflatoxin-producing strain of Aspergillus flavus.
    2. Magnitude of residue at the time of harvest and method used to 
determine the residue. Aspergillus flavus AF36 is a naturally occurring 
fungus isolated from cottonseed produced in the Yuma Valley of Arizona. 
Aspergillus flavus AF36 has been shown to be naturally and consistently 
associated with commercial cotton grown in Arizona. Other than 
immediately after application, the overall quantity of Aspergillus 
flavus at time of harvest on cottonseed grown in fields where 
Aspergillus flavus AF36 has been applied and has been shown to be 
similar to levels on cottonseed grown in fields where no application 
was made. Aspergillus flavus is a widespread fungus. It is particularly 
well adapted to the hot desert regions of Arizona where it is 
widespread in the environment. The communities of Aspergillus flavus in 
the desert and in agricultural fields are naturally composed of both 
aflatoxin producing (toxigenic) and aflatoxin non-producing 
(atoxigenic) strains. Both atoxigenic and toxigenic strains have been 
found on essentially all plant material and soils in the desert valleys 
of Arizona. The goal of applications is to increase the percent of the 
Aspergillus flavus community composed of the atoxigenic strain AF36 and 
to decrease the percent of Aspergillus flavus that produces aflatoxins 
on the crop and in the fields.
    3. A statement of why an analytical method for detecting and 
measuring the levels of the pesticide residue are not needed. An 
exemption from the requirement of a tolerance for residues of the 
microbial pesticide Aspergillus flavus AF36 in/on cotton is being 
proposed for cotton treated in Arizona and Texas. Aspergillus flavus 
isolate AF36, when applied to the soil just prior to bloom has been 
shown to significantly reduce the levels of aflatoxin in cottonseed at 
harvest. Aflatoxin levels in cottonseed products are regulated by the 
Food and Drug Administration (FDA). FDA does not allow cottonseed 
products containing aflatoxin at 20 parts per billion (ppb), or higher 
to be used in dairy rations. FDA regulations also do not allow 
cottonseed products containing aflatoxin above 300 ppb, to be used for 
feeding beef cattle. All lots of the active ingredient (Aspergillus 
flavus isolate AF36) and the formulated products are monitored for 
aflatoxin production as part of a rigorous quality control program. 
Starter cultures of Aspergillus flavus isolate AF36 used in the 
production of the end-use product are always screened for strain 
identity by vegetative

[[Page 7557]]

compatibility, and for aflatoxin production using thin layer 
chromatography and appropriate standards. Quality control standards are 
zero tolerance in the starter cultures and in the formulated product 
for aflatoxin production, and for Aspergillus flavus not identified as 
Aspergillus flavus isolate AF36. Aspergillus flavus AF36 has never been 
found to produce aflatoxin.

C. Mammalian Toxicological Profile

    An acute oral toxicity test was performed whereby a single oral 
dose of 5,000 milligrams/kilogram body weight (mg/kg/bwt) per animal of 
Aspergillus flavus AF36 colonized wheat seed was administered by gavage 
to five male and five female Sprague Dawley rats. The oral 
LD50 of Aspergillus flavus AF36 was determined to be greater 
than 5,000 mg/kg rat body weight. No clinical signs were observed 
during the 14-day study and no abnormalities or adverse effects were 
observed in any of the rats upon necropsy.
    An initial pulmonary rat study resulted in lethality in a 
significant number of animals treated with either the live Aspergillus 
flavus AF36 in Tween 80 or heat killed Aspergillus flavus AF36 in Tween 
80. Onset of symptoms was rapid after dosing with all deaths occurring 
by day 4 of the study. All rats surviving to day 4 of the study 
recovered and all rats sacrificed (as scheduled) on day 8 or day 15 of 
the study had totally eliminated viable Aspergillus flavus AF36 from 
the lungs, caecal contents, and feces. There was no evidence of 
infectivity. The aetiology of deaths was unclear. It appeared that 
Aspergillus flavus AF36 prepared as a test substance with Tween 80 
caused a severe acute inflammatory response. Retrospective literature 
review and consultation with a toxicologist supported the theory that 
the responses were a result of a synergism with Tween 80 and/or of 
Tween 80 breakdown products formed during preparation of the spore 
suspension test substance.
    A second rat pulmonary study was therefore undertaken. In the 
second study the conidia were both washed from the wheat and suspended 
in sterile physiological saline instead of Tween 80. Animals (2 male 
and 2 female for each treatment level) were dosed at 0, 10\5\, 10\6\, 
10\7\, and 10\8\ colony forming units per rat. There were no clinical 
signs in any of the treatment groups considered to be associated with 
the test substance. Rats were sacrificed at day 8 without treatment 
associated mortality. No abnormalities were observed in any of the 
animals at the macroscopic examination at termination.
    Based on these two mammalian studies, the petitioner concludes that 
Aspergillus flavus AF36 does not present either a toxicological or an 
infectious risk to mammals. Data waivers were requested for the 
following toxicology studies: Acute dermal toxicology/pathology, 
primary dermal irritation, primary eye irritation, and acute 
intraperitoneal toxicology/pathology effects of the microbial 
pesticide. The following rationales were used as a basis for the data 
waiver requests:
    ? Researchers and other workers have worked with Aspergillus 
flavus AF36 at the Southern Regional Research Center for over 10 years 
and in commercial fields (1996 to 1998) and in hand-picked field plots 
(1989 to 1994) without report of any adverse health effects.
    ? Aspergillus flavus AF36 is widely distributed in the 
environment and its occurrence is natural.
    ? The label will require applicators and other handlers to 
wear Personal Protective Equipment (PPE) such as waterproof gloves, a 
dust/mist filtering respirator with the appropriate NIOSH approval 
prefix N-95, P-95, or R-95, coveralls, long sleeved shirt and long 
pants, and shoes plus socks, and goggles, to mitigate against dermal 
and primary eye irritation exposure.
    The pesticide is to be applied aerially by mixers/handlers and 
applicators who are licensed and trained to handle restricted 
materials. At the 10 lb/acre application rate of the formulated 
material, the total amount of active ingredient is less than 0.01 lb/
acre. Applications of AF36 do not significantly impact the total amount 
of Aspergillus flavus in the soil or crop, but only change the 
proportion of the AF36 strain in relation to the overall soil 
population. Since the product is applied to cotton fields as a granular 
formulation on colonized wheat seeds, exposure from drift is minimal.
    In addition, the following rationales were advanced in support of 
the data waiver requests for acute dermal toxicity and primary dermal 
irritation. These studies were waived during the experimental use 
program, based upon the lack of toxicity in animals dosed orally. While 
other Aspergillus flavus strains have been reported to be dermal 
sensitizers, this testing is not warranted, since the aerial method of 
application and the PPE required on the label will mitigate dermal 
exposure to workers and pesticide handlers. The acute intraperitoneal 
study was waived based upon the lack of toxicity in animals dosed 
orally and by pulmonary/intratracheal instillation.
    Genotoxicity, reproductive and developmental toxicity, subchronic 
toxicity and chronic toxicity testing were not performed, since no 
adverse effects were observed in the acute toxicology study Tier 1 
studies. Tier II (885.3550), subchronic toxicology study (EPA OPPTS 
885.3600) and chronic feeding studies (guideline 152-50) are only 
required if triggered by adverse effects observed in Tier I studies.

D. Aggregate Exposure

    1. Dietary exposure--i. Food. Aspergillus flavus AF36 is a 
naturally occurring organism, which does not produce aflatoxin and is 
thus safer than the aflatoxin-producing Aspergillus flavus isolates. 
Proposed uses and application rates will not result in increases in the 
total population of Aspergillus flavus on the mature crop beyond 
naturally occurring background levels. FDA does not allow cottonseed 
products containing aflatoxin at 20 ppb or higher to be used in dairy 
rations. FDA regulations also do not allow cottonseed products 
containing aflatoxin levels above 300 ppb, to be used for feeding beef 
cattle.
    Aspergillus flavus AF36, when applied to the soil just prior to 
bloom, has been shown to significantly reduce the levels of aflatoxin 
in cottonseed at harvest. Furthermore, the proposed use and application 
rate will not increase exposure of humans to Aspergillus flavus by 
dietary means, since cotton itself is not a food product for human 
consumption. There is minimal dietary exposure to Aspergillus flavus 
from cottonseed. There is no mechanism for Aspergillus flavus to be 
transferred from the seed to animal products and there is no evidence 
that the fungus readily contaminates meat or milk. Seed is typically 
extracted for oil with hexane and that process kills the fungus. 
Furthermore, applications of Aspergillus flavus AF36 do not increase 
the indigenous populations of Aspergillus flavus associated with the 
harvested crop. The applications merely alter the composition of the 
fungal community associated with the mature crop so that aflatoxin 
producing strains are far less frequent. The result is a much lower 
incidence of aflatoxins in the crop and in the environment associated 
with the developing and mature crop.
    ii. Drinking water. Aspergillus flavus AF36 is a naturally 
occurring organism that is already widespread in the environment and is 
not considered to be a risk to drinking water. Both percolation through 
soil and municipal treatment of drinking water would reduce the 
possibility of exposure of Aspergillus flavus through the drinking

[[Page 7558]]

water. Applications of Aspergillus flavus AF36 do not increase the 
long-term populations of Aspergillus flavus in the environment, and 
thus are not expected to influence the relationship of Aspergillus 
flavus to water sources. Applications merely change the composition of 
the Aspergillus flavus community so that aflatoxin producing strains 
are less common in the environment.
    2. Non-dietary exposure.The potential for non-occupational, non-
dietary exposure to the general population is not expected to be 
significant and is not expected to present any risk of adverse health 
effects.

E. Cumulative Exposure

    There are no other registered products containing Aspergillus 
flavus AF36 or any other isolates (strains) of the microbial active 
ingredient. Data submitted show that the fungal metabolite of concern, 
which is aflatoxin, is not produced by Aspergillus flavus AF36 in the 
crop or in artificial media in the lab. When applied prior to 
flowering, Aspergillus flavus AF36 has been shown to exclude aflatoxin 
producing fungi competitively from the developing crop and to reduce 
aflatoxin contamination of cottonseed. Data show that the proposed use 
will not result in appreciable increases in the long-term population of 
Aspergillus flavus on the crop beyond naturally occurring levels. 
Furthermore, there is no expectation of cumulative effects with other 
pesticides.

F. Safety Determination

    1. U.S. population. Aspergillus flavus AF36 is a naturally 
occurring organism. This isolate has low toxicity as demonstrated by 
the acute oral toxicity study in rats. Aspergillus flavus is ubiquitous 
throughout the hot desert valleys in Arizona. Studies have shown that 
treatment of cotton fields just prior to flowering with sterile wheat 
seed colonized by Aspergillus flavus AF36 at 10 lb per acre does not 
increase the long-term populations of Aspergillus flavus either on the 
crop at maturity or in the soil 1 year after application. Based on this 
information, Interregional Research Project Number-4 is of the opinion 
that the aggregate exposure to Aspergillus flavus over a lifetime 
should not change with application of Aspergillus flavus AF36, and 
exposure to both aflatoxin producing Aspergillus flavus strains and 
aflatoxin should decrease. This should be beneficial to human health. 
Thus, there is a reasonable certainty that no harm will result from 
aggregate exposure to Aspergillus flavus AF36.
    2. Infants and children. Based on the lack of toxicity and natural 
occurrence, there is reasonable certainty that no harm to infants, 
children, or adults will result from aggregate exposure to Aspergillus 
flavus AF36. Exempting Aspergillus flavus AF36 from the requirement of 
a tolerance should pose no significant risk to humans or the 
environment.

G. Effects on the Immune and Endocrine Systems

    Aspergillus flavus AF36 is a naturally occurring organism, which 
does not produce aflatoxin, and is thus safer than the Aspergillus 
flavus isolates that produce aflatoxin. To date there is no evidence to 
suggest that Aspergillus flavus AF36 functions in a manner similar to 
any known hormone, or that it acts as an endocrine disrupter.

H. Efficacy

    Existence of aflatoxins in the environment is a public health 
hazard. Data were submitted to demonstrate that proper use of 
Aspergillus flavus AF36 results in reductions in the average aflatoxin 
producing potential of fungi resident in treated areas and in 
reductions in the quantity of aflatoxins in crops. In field tests prior 
to 1996, the aflatoxin content of cottonseed was shown to be inversely 
related to the proportion of the Aspergillus flavus community on the 
crop composed of Aspergillus flavus AF36. Detailed analyses of the 
aflatoxin content of commercial fields from 1996 through 1998 confirmed 
that reduced aflatoxin levels were associated with displacement of 
aflatoxin producers by Aspergillus flavus AF36 from treated crops and 
that treatments were associated with up to 90% reductions in crop 
aflatoxin content.
    Efficacy of applications of Aspergillus flavus AF36 in displacing 
aflatoxin producers was demonstrated for fungal communities both on 
cottonseed from treated crops at harvest and in soils of treated fields 
1 year after treatment. This included cotton crops treated in 1996 (112 
acres treated), 1997 (463 acres treated), 1998 (499 acres), 1999 
(10,488 acres), 2000 (16,725 acres), and 2001 (19,975 acres treated). 
The proportion of Aspergillus flavus communities composed of 
Aspergillus flavus AF36 indicates the extent to which aflatoxin 
producers were displaced. In 1996 average incidence of AF36 on treated 
crops was 88.5% and in the soil, 1 year after treatment, incidence of 
AF36 was 85.2%. Incidences of AF36 on treated crops were 78% and 67% in 
1997 and 1998, respectively, and in soil 1 year after treatment, AF36 
incidences were 72% and 77%, respectively. Successful displacement was 
also observed as the acreage treated rapidly expanded from 1999 to 2001 
with average incidences of AF36 on treated crops ranging from 57% in 
1999 to 66% in 2001.
    Aflatoxin-producing S strain isolates of Aspergillus flavus are 
prominent in soils of cotton producing areas of Arizona and south 
Texas. They produce more aflatoxins than other Aspergillus flavus 
isolates such as the non-aflatoxin-producing L strain Aspergillus 
flavus AF36. Applications of AF36 during the experimental program were 
effective at displacing the high aflatoxin producing S strain of 
Aspergillus flavus. During the course of the experimental use program, 
Aspergillus flavus AF36 also caused long-term reductions in the 
aflatoxin producing potential of fungal communities in agricultural 
fields. Aspergillus flavus AF36 retained atoxigenicity (failure to 
produce aflatoxins) upon repeated reisolation from treated fields 1, 2, 
or 3 years after treatment. Thus, there was a long-term reduction in 
the potential of fungal communities to produce aflatoxins in treated 
areas. The average aflatoxin producing potential of Aspergillus flavus 
communities resident in soils of treated fields was reduced on average 
73% 1 year after treatment over the 3 year period (1996 to 1999). S 
strain isolates, which produced very high levels of aflatoxins, with 
field averages ranging from 7,100 ppb, aflatoxin to 22,700 ppb, 
aflatoxin, were effectively displaced. Their incidence was reduced from 
initially composing 46% of Aspergillus flavus soil communities to 
composing on average of 11%.

I. Existing Tolerances

    The registrant is not aware of any existing tolerances or tolerance 
exemptions for Aspergillus flavus AF36, other than the temporary 
tolerance exemption on cotton (40 CFR 180.1206) in conjunction with an 
EUP, which expires on December 30, 2004.

J. International Tolerances

    There are no Codex maximum residue levels established for residues 
of Aspergillus flavus AF36. Aspergillus flavus AF36 containing products 
are presently not registered for pest control outside of the United 
States.

[FR Doc. 03-3696 Filed 2-13-03; 8:45 am]
BILLING CODE 6560-50-S 

 
 


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