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Notice

Potassium Silicate; Notice of Filing a Pesticide Petition to Establish a Tolerance for a Certain Pesticide Chemical in or on Food

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Information about this document as published in the Federal Register.

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This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

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AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Notice.

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.

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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: frazer.carol@epa.gov.

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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 Start Printed Page 43418Industrial 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 opp-docket@epa.gov, 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.

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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 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.

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List of Subjects

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Dated: July 11, 2005.

Janet L. Andersen,

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

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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. Start Printed 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/Na2 O 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.

StudyGuidelineResultCategoryComments
Acute oral81-1>5 g/kgIV
Acute dermal81-2>5 g/kgIV
Acute inhalation81-3>2.06 mg/Liter (L)IV
Acute eye irritation81-4Score=12III
Acute dermal irritation81-5SlightIVClears in 72 hours
Acute dermal sensitization81-6Not Sensitizing

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 Start Printed Page 43421section 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.

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[FR Doc. 05-14864 Filed 7-26-05; 8:45 am]

BILLING CODE 6560-50-S