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6-Benzyladenine; Notice of Filing a Pesticide Petition to Establish a Tolerance for a Certain Pesticide Chemical in or on Food

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


 
[Federal Register: July 30, 2003 (Volume 68, Number 146)]
[Notices]
[Page 44777-44780]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr30jy03-55]

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ENVIRONMENTAL PROTECTION AGENCY
[OPP-2003-0223; FRL-7315-7]
 
6-Benzyladenine; Notice of Filing a Pesticide Petition to 
Establish a Tolerance for a Certain Pesticide Chemical 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 chemical in or on various food commodities.

DATES: Comments, identified by docket identification (ID) number OPP-
2003-0223, must be received on or before August 29, 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: Denise Greenway, Biopesticides and 
Pollution Prevention Division (7511C), Office of Pesticide Programs, 
Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460-0001; telephone number: (703) 308-8263; e-mail 
address: greenway.denise@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 entities may include, but are not limited to:
    ? Crop production (NAICS 111)
    ? Animal production (NAICS 112)
    ? Food manufacturing (NAICS 311)
    ? Pesticide manufacturing (NAICS 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. 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 ID number OPP-2003-0223. 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 EPA's 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 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.1. 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

[[Page 44778]]

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-2003-0223. 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-2003-0223. 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-2003-0223.
    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-2003-0223. 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.
    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 recordkeeping 
requirements.

    Dated: July 16, 2003.
Janet L. Andersen,
Director, Biopesticides and Pollution Prevention Division, Office of 
Pesticide Programs.

Summary of Petition

    The petitioner's 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.

I. Valent BioSciences Corporation

PP 3F6586

    EPA has received a pesticide petition (PP 3F6586) from Valent 
BioSciences Corporation, 870 Technology Way, Suite 100, Libertyville, 
IL. 60048, proposing pursuant to section 408(d) of the FFDCA, 21 U.S.C. 
346a(d), to amend 40 CFR part 180 to establish an exemption from the 
requirement of a tolerance for the biochemical pesticide 6-
benzyladenine (6-BA) in or on pistachio, and to amend the existing 
exemption (Sec. 180.1150) for apples to expand the uses and increase 
the application rate.
    Valent BioSciences Corporation has submitted the following summary 
of

[[Page 44779]]

information, data, and arguments in support of their pesticide 
petition. This summary was prepared by Valent BioSciences Corporation 
and 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

    6-Benzyladenine is a naturally occurring plant growth regulator 
used on certain fruit trees and certain ornamental lily tubers. In 
January 1990, the Agency classified 6-BA as a biochemical pesticide 
because it resembles natural plant regulators and it displays a 
nontoxic mode of action. The new use being proposed for 6-BA is as an 
effective stand-alone fruitlet thinner when applied to apples in the 
post-bloom period at an application rate not to exceed 182 grams of 
active ingredient per acre per season (gram per active ingredient per 
acre per season). 6-Benzyladenine has also been shown to directly 
increase cell division of treated fruit, resulting in improvements in 
fruit size over what would be expected from the normal thinning effect. 
The frequency and timing of application will vary according to the 
specific growing conditions being treated. The second proposed new use 
is to reduce alternate bearing in pistachio and thus increase 
cumulative yield. The proposed maximum application rate for pistachio 
is 60 grams of active ingredient per acre per season.

B. Product Identity/Chemistry

    1. Identity of the pesticide and corresponding residues. 6-
Benzyladenine (N-(phenylmethyl)-1H-purin-6-amine) has been tested and 
residue data generated has been provided to EPA by Valent BioSciences 
Corporation.
    2. Magnitude of residue at the time of harvest and method used to 
determine the residue. Trials conducted in various states (New York, 
Pennsylvania, Virgina, Missouri, Oregon, and Washington) and on various 
apple cultivars, support the proposed tolerance exemption. This data 
has been further supported by numerous trials carried out 
internationally. Residue levels following the maximum number (4) of 
applications on apple were very close to the limit of quantitation 
(LOQ) of 5 parts per billion (ppb) at normal harvest, which averaged 80 
days after the last application. Trials indicate rapid degradation of 
6-BA residues among all the apple varieties and geographies evaluated.
    The analytical methods for detection of 6-BA in apple raw 
agricultural and processed commodities are comprised of extraction, 
cleanup on a strong cation exchange (SCX) solid-phase extraction 
cartridge, derivatisation and quantitation by gas chromatography (GC). 
These were developed by Valent BioSciences Corporation and submitted to 
EPA, constituting a practical analytical method for detecting and 
measuring levels of 6-BA in or on commodities, with a LOQ of 0.005 part 
per million (ppm) that allows for monitoring of food, with the residues 
at or above the LOQ.
    Residue data on 6-BA use on pistachio has been provided to EPA by 
Valent BioSciences Corporation. Trials were conducted in locations 
representing the major pistachio production area in the United States. 
No residues were detected following the maximum number (2) of 
applications at normal harvest, which averaged 60 days after the last 
application.
    An analytical method based on extraction, clean up and 
derivatisation of 6-BA followed by quantitation by GC was submitted to 
EPA for residue determination on pistachio. This GC method is adequate 
for determining residues in or on pistachios with a LOQ of 0.05 ppm.
    3. Why an analytical method for detecting and measuring the levels 
of the pesticide residue are not needed. Usually, a request for an 
exemption from the requirement of a tolerance is not accompanied by 
residue data and an analytical method. Valent BioSciences Corporation 
has provided this information to the Agency in this case. The 
information demonstrates that any residue is detected at levels very 
close to the LOQ. Although a numeric tolerance could be established, it 
would be very difficult to enforce, as demonstrated by the risk 
characterization. Valent BioSciences Corporation proposes that the 
submitted residue data and analytical method support their conclusion 
that there is a reasonable certainty that no harm to humans or the 
environment will result from the use of 6-BA on apples and pistachios.

C. Mammalian Toxicological Profile

    1. Acute toxicity. The oral LD50 of 6-BA is estimated by 
probit analysis at 1.3 gram/kilogram (g/kg) in the rat. The dermal 
LD50 in the rabbit is >5.0 g/kg. The acute inhalation 
LC50 in the rat is 5.2 milligrams/Liter (mg/L)/hour. A 
primary eye irritation study in the rabbit showed moderate conjunctival 
effects which cleared within 7 days. A dermal irritation study in the 
rabbit showed slight dermal irritation, which lasted for 5 days. 
Sensitization potential has been examined, and 6-BA (99% pure) was 
demonstrated not to be a dermal sensitizer in guinea pigs under 
conditions of the study.
    2. Genotoxicity. Mutagenicity studies including Ames test, mouse 
micronucleus assay, and unscheduled DNA synthesis (UDS) assay in rat 
were negative for mutagenic effects.
    3. Developmental toxicity. Developmental toxicity in rats fed 6-BA 
(99% pure) was manifested as significantly decreased fetal body weight, 
increased incidence of hydrocephalas and unossified sternbrae, 
incompletely ossified phalanges, and malaligned sternbrae at 175 
milligrams/kilogram body weight/day (mg/kg bwt/day).
    Maternal toxicity was also observed at 175 mg/kg bwt/day, which was 
manifested as significantly decreased body weight, weight gain, and 
food consumption. Thus the no observed adverse effect level (NOAEL) and 
lowest observed adverse effect level (LOAEL) for maternal and 
developmental toxicity was 50 and 175 mg/kg bwt/day, respectively.
    4. Subchronic toxicity. 6-Benzyladenine (99% pure) fed to rats for 
13 weeks produced decreased weight gain at 1,500 and 5,000 ppm (121 and 
322 mg/kg bwt/day) in females, and 5,000 ppm (295 mg/kg bwt/day) in 
males. This decreased weight gain appeared to be related to decreased 
food consumption. Serum alkaline phosphatase activity and blood urea 
nitrogen levels were increased in both sexes receiving 5,000 ppm; thus 
the NOAEL was 1,500 ppm (approximately 111 mg/kg bwt/day in both sexes 
combined) and the LOAEL was 5,000 ppm (approximately 304 mg/kg bwt/day 
in both sexes), based on the decreased body weight gain, food 
consumption, increased blood urea nitrogen, and minimal histological 
changes in the kidneys.

D. Aggregate Exposure

    1. Dietary exposure--i. Food. In conducting this exposure 
assessment, Valent BioSciences Corporation used very conservative 
assumptions, 100% of all commodities were assumed to be treated, and 
those residues would be at twice the LOQ -- which result in a large 
overestimate of human exposure. The analysis assumes that all residues 
have the same magnitude, and the treated

[[Page 44780]]

commodity is 100% of a daily diet. Thus, in making a safety 
determination for these tolerance exemptions, Valent BioSciences 
Corporation took into account this very conservative exposure 
assessment.
    The last application precedes harvest by approximately 2.5 months 
in apples, therefore the potential for dietary exposure is considered 
negligible by Valent BioSciences Corporation. Application precedes 
harvest by approximately 2 months in pistachios. Also pistachios have 
their hulls, which cover the shell, removed at harvest, therefore the 
potential for dietary exposure is considered negligible by Valent 
BioSciences Corporation. Residues are below the LOQ (LOQ = 0.05 ppm) in 
pistachio.
    ii. Drinking water. The proposed uses on apples and pistachios are 
not expected to add potential exposure to drinking water. Soil leaching 
studies have suggested that 6-BA is relatively immobile, absorbing to 
sediment. Residues reaching surface waters from field runoff should 
quickly absorb to sediment particles and be partitioned from the water 
column. 6-Benzyladenine also has low solubility in water, 0.061 mg/mL, 
and detections in ground water are not expected. Valent BioSciences 
Corporation concludes that together these data indicate that residues 
are not expected in drinking water.
    2. Non-dietary exposure. The proposed uses involve application of 
6-BA to crops grown in an agricultural environment. The only non-
dietary exposure expected is that to applicators. However, the 
protective measures prescribed by the product's label are expected to 
be adequate to minimize exposure and protect applicators of the 
chemical.

E. Cumulative Exposure

    No cumulative adverse effects are expected from long-term exposure 
to this chemical. There is no reliable information to indicate that 
toxic effects produced by 6-BA would be cumulative with those of any 
other pesticide chemical.

F. Safety Determination

    1. U.S. population. Chronic dietary exposure estimates were 
conducted for the overall U.S. population and 25 population subgroups, 
including infants and children. These estimated daily intakes were 
compared against a chronic population adjusted dose (PAD) based on a 
NOAEL of 50 mg/kg bwt/day from a developmental study in rats. To 
account for intraspecies and interspecies variation and the use of an 
acute toxicological endpoint for a chronic assessment, an uncertainty 
factor (UF) of 1,000 was applied to the acute NOAEL. This resulted in a 
chronic PAD of 0.05 mg/kg bwt/day. Daily exposure for the overall U.S. 
population was estimated to be 0.000014 mg/kg bwt/day, representing 
less than 0.1% of the estimated chronic PAD.
    2. Infants and children. Estimated daily exposures, assuming that 
100% of the apple and pistachio commodities in the United States are 
treated with 6-BA, for the most highly exposed population subgroup, 
non-nursing infants, was estimated to be 0.000085 mg/kg bwt/day, or 
0.2% of the estimated chronic PAD.

G. Effects on the Immune and Endocrine Systems

    6-Benzyladenine is a naturally occurring cytokinin which has plant 
growth regulator properties. There is no indication that this plant 
growth regulator belongs to a class of chemicals known or suspected of 
having adverse effects on the immune and endocrine systems. It can be 
concluded that based upon the existing toxicology there would be no 
adverse effects on the immune or endocrine systems from the use of 6-
BA. Last, there is no evidence that 6-BA bioaccumulates in the 
environment.

H. Existing Tolerances

    The plant growth regulator 6-BA is exempt from the requirement of a 
tolerance when used as a fruit-thinning agent at an application rate 
not to exceed 30 grams of active ingredient per acre in or on apples.
    6-Benzyladenine is temporarily exempt from the requirement of a 
tolerance in or on apples at 182 grams of active ingredient per acre per 
season, and in or on pistachio at 60 grams of active ingredient per acre 
per season when used in accordance with the Experimental Use Permit 
73049-EUP-2. The exemption from a tolerance will expire on January 31, 
2005.

I. International Tolerances

    There are no codex, Canadian, or Mexican maximum residue limits for 
use of 6-BA on apple or pistachio.

[FR Doc. 03-19280 Filed 7-29-03; 8:45 am]
BILLING CODE 6560-50-S 

 
 


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