[Federal Register Volume 70, Number 143 (Wednesday, July 27, 2005)]
[Notices]
[Pages 43417-43421]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-14864]


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ENVIRONMENTAL PROTECTION AGENCY

[OPP-2005-0166; FRL-7719-5]


Potassium Silicate; 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-
2005-0166, must be received on or before August 26, 2005.

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: Carol E. Frazer, Biopesticides and 
Pollution Prevention Division (7511C), Office of Pesticide Programs, 
Environmental Protection Agency, 1200 Pennsylvania Ave., NW., 
Washington, DC 20460-0001; telephone number: (703) 308-8810; e-mail 
address:[email protected].

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this Action Apply to Me?

    You may be potentially affected by this action if you an 
agricultural producer, food manufacturer, or pesticide manufacturer. 
Potentially affected 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

[[Page 43418]]

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-2005-0166. 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, 1801 S. Bell St., 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.epa.gov/edocket/ 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 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 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-2005-0166. 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 [email protected], 
Attention: Docket ID Number OPP-2005-0166. 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.

[[Page 43419]]

    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-2005-0166.
    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, 1801 S. Bell St., Arlington, VA, Attention: Docket ID 
Number OPP-2005-0166. 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 assignedto this action in the subject line on the first page 
of your response. You may also provide thename, 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 11, 2005.
Janet L. Andersen,
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.

PQ Corporation

PP 5F6905

    EPA has received a pesticide petition 5F6905 from PQ Corporation, 
P.O. Box 840 Valley Forge, PA 19482-0840 proposing, pursuant to section 
408(d) of the Federal Food, Drug, and Cosmetic Act (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 potassium salt 
of silicic acid (potassium silicate).
    Pursuant to section 408(d)(2)(A)(i) of FFDCA, as amended, PQ 
Corporation has submitted the following summary of information, data, 
and arguments in support of their pesticide petition. This summary was 
prepared by PQ 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

    The new active ingredient proposed in this petition is potassium 
silicate. The products formulated from this active ingredient will be 
sold under the product name Agsil. Potassium silicate is the potassium 
salt form of silicic acid. Dilute aqueous solutions of potassium 
silicate (about 1% or less when tank mixed), will be applied to fruit 
crops, nuts, vegetable crops, and vine crops, and as a fungicidal 
pesticide (against such diseases as powdery mildew) and as an 
insecticide (for use against the pests such as spider mites and 
whiteflies).

B. Product Identity/Chemistry

    1. Identity of the pesticide and corresponding residues.After 
aqueous formulating, potassium silicate consists of potassium and 
silicic acid (Si(OH)4).
    2. Magnitude of residue at the time of harvest and method used to 
determine the residue. In plants Si(OH)4 is rapidly absorbed 
and enhances growth and plant vigor. Currently potassium silicates are 
sold as fertilizer. Once absorbed, silicic acid is readily circulated 
throughout the plant and deposited as silicon dioxide.
    3. A statement of why an analytical method for detecting and 
measuring the levels of the pesticide residue are not needed. The 
primary function of silicon in plants is to enhance the absorption and 
translocation of macro and micro nutrients. The primary benefit of 
silicon is the even distribution of these nutrients through the plant, 
enhancing overall total plant vigor. Silicon also enhances plant 
structural strength by increasing rigidity within cell walls.

[[Page 43420]]

 This also enhances plant thriving and vigor.
    Since both potassium and silicic acid are rapidly absorbed and 
utilized by plants, it is not possible to detect residues of potassium 
silicate applied as an insecticide essentially 24 hours after 
application. Silicates such as potassium silicate are not discernable 
from silicates found ubiquitously within crops and the environment in 
general. Further given the significant percentage of crop tissues that 
contain silicon dioxide, it is unlikely that any significant increase 
in silica concentration due to silicate pesticide applications would 
occur.

C. Mammalian Toxicological Profile

    Solutions of sodium silicate are used for corrosion control in 
potable water as allowed by the EPA. Potassium silicate is Generally 
Regarded as Safe (GRAS) by the Food and Drug Adminsitration (FDA). 
Silica is naturally present in municipal drinking water at about 8 
parts per million (ppm). Because of their ubiquitous distribution in 
water, soil and plant, and animal tissue, they are consumed on a daily 
basis. The FDA has determined that potassium silicate is identical in 
chemical properties to sodium silicate. Sodium metasilicate (sodium 
silicate with a SiO2/Na2O weight ratio of 1:1) 
and sodium silicate are currently exempt from the requirement of a 
tolerance on crops (40 CFR 180.1001 (c)).
    1. Acute toxicity. Neither sodium nor potassium silicate are orally 
toxic. Studies on both substances in Europe have found the 
LD50 to exceed 2,000 milligram/kilogram (mg/kg). The World 
Health Organization puts the oral LD50 in rats for silicic 
acid at 3.16 gram/kilogram (g/kg) body weight and for mice at >5 gram/
kg body weight. Several studies on various concentrations of sodium 
silicate found LD50 values ranging from 1,300 mg/kg to 
>10,000 mg/kg. The estimated LD50 dose for silicic acid for 
man is >15 g/kg body weight. The estimated LD50 for a 
solution of sodium silicate (and therefore potassium silicate) is 
estimated between 0.5 and 5.0 g/kg body weight with toxicity due more 
to the higher alkalinity of the solution.
    Potassium silicate will be applied to crops in dilute solutions. 
The end use products will contain 29% potassium silicate or less. The 
applications solutions will contain less than 1% potassium silicate. A 
full acute toxicology battery has been completed on a 29% w/w aqueous 
potassium silicate solution. The results of those studies are tabulated 
in the table in this unit.


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              Study                    Guideline            Result             Category            Comments
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Acute oral                        81-1                >5 g/kg             IV                  ..................
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Acute dermal                      81-2                >5 g/kg             IV                  ..................
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Acute inhalation                  81-3                >2.06 mg/Liter (L)  IV                  ..................
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Acute eye irritation              81-4                Score=12            III                 ..................
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Acute dermal irritation           81-5                Slight              IV                  Clears in 72 hours
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Acute dermal sensitization        81-6                            Not Sensitizing             ..................
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    2. Genotoxicity.DNA damage and repair assay and reverse mutation 
assays conducted on sodium silicate were negative for genotoxic 
effects. A 2-year chronic toxicity study was negative for 
carcinogenicity.
    3. Reproductive and developmental toxicity. A 1-generation rat 
reproduction study with the oral administration of 790 ppm and 1,580 
ppm sodium silicate (equivalent to 600 ppm and 1,200 ppm silicon 
dioxide) was conducted for 180 days. No adverse effects were noted. A 
2-generation reproduction study with the oral administration of 100 mg/
kg body weight (bw) per day amorphous silica to rats was also 
conducted. The parent generation (one male and five females) produced 
five litters with a total of 25 rats. Half a year later, one male and 
five females of the first generation were mated; the number of animals 
in the second generation was 21. Neither malformation nor any other 
adverse effects were noted. In summary, no chronic detrimental effects 
were noted for intake of silicates. In fact positive nutritional 
aspects were noted in most of the studies.
    4. Animal metabolism. Some amount of silica is normally present in 
all body tissues. Silicic acid is a normal constituent of urine with 
excreted values ranging from 10-30 mg/day. The silica content of human 
tissue varies from 10-200 mg/100 g dry weight.

D. Aggregate Exposure

    1. Dietary exposure--i. Silicic acid salts are the most common form 
of silicon. Silicon is a nutritional trace element required for proper 
and strong growth of mammalian bones. In plants, silicic acid 
(Si(OH)4) is rapidly absorbed. Once absorbed, silicic acid 
is readily circulated throughout the plant and deposited as silicon 
dioxide. Consequently, exposure to soluble silica occurs on a daily 
basis and is a property of all plant products in human diet. The 
concentration of silicon in vegetable plants varies greatly with 
cereals and grasses containing the highest concentrations (0.2-2.0%). 
Further, silica is approved by the FDA for use as an anti-caking agent 
in food.
    ii. Drinking water. Silicate is used as a corrosion inhibitor for 
potable water. The use rate for municipal water supplies is 8 ppm.
    2. Non-dietary exposure. Silicon comprises 31% of the Earth's 
crust. Silicic acid salts (silicates) are the most common form of 
silicon. Consequently, exposure to silicates is widespread in 
activities involving contact with soil and natural water.

E. Safety Determination for U.S. population, Infants and Children

    Section 408 of FFDCA provides that EPA shall apply an additional 
tenfold margin of exposure (MOE) for infants and children in the case 
of threshold effects to account for pre- and post-natal toxicity and 
the completeness of the database, unless EPA determines that a 
different MOE will be safe for infants and children.
    MOEs are often referred to as uncertainty (safety) factors. In this 
instance, the Agency believes that there are reliable data to support 
the conclusion that the subject active ingredient when used as a 
systemic acquired resistence (SAR) inducer, are practically non-toxic 
to mammals, including infants and children, and, thus, there are no 
threshold effects, and EPA has not used a MOE approach to assess their 
safety. As a result, the provision requiring an additional MOE does not 
apply. Consistent with FFDCA

[[Page 43421]]

section 408(b)(2)(D), EPA has reviewed the available scientific data 
and other relevant information in support of this action. Based on the 
information and data considered, the Agency has determined that use of 
this pesticide as a SAR inducer will not pose a dietary risk under 
reasonably foreseeable circumstances.
    Accordingly, EPA concludes that, in amending 40 CFR part 180, to 
establish the exemptions as proposed, there is a reasonable certainty 
that no harm to the general population, including infants and children, 
will result from aggregate exposure to the pesticide chemical residues 
of the subject active ingredient, when used as a SAR inducer. The 
safety of infants and children is supported by oral toxicity data 
indicating that, for the subject active ingredient, the doses must 
exceed 5,000 mg/kg before toxicity occurs.

F. Endocrine Disruption

    The Agency has no information that suggests silicates will have an 
effect on the immune or endocrine system. Given the widespread presence 
of natural silicates such effects are highly unlikely.

G. International Tolerances

    There are no CODEX, national or international, tolerance exemptions 
established for the subject active ingredient at this time.

[FR Doc. 05-14864 Filed 7-26-05; 8:45 am]
BILLING CODE 6560-50-S