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Dimethyl silicone polymer with silica; silane, dichloromethyl-, reaction product with silica; hexamethyldisilizane, reaction product with silica; Tolerance Exemption

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


 [Federal Register: September 29, 2000 (Volume 65, Number 190)]
[Rules and Regulations]
[Page 58399-58404]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr29se00-13]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 180

[OPP-301055; FRL-6745-1]
RIN 2070-AB78


Dimethyl silicone polymer with silica; silane, dichloromethyl-,
reaction product with silica; hexamethyldisilizane, reaction product
with silica; Tolerance Exemption

AGENCY:  Environmental Protection Agency (EPA).

ACTION:  Final rule.

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SUMMARY:  This regulation establishes an amendment to the exemptions
from the requirement of a tolerance for residues of dimethyl silicone
polymer with silica; silane, dichloromethyl-, reaction product with
silica; and hexamethyldisilizane, reaction product with silica; when
used as inert ingredients on growing crops, when applied to raw
agricultural commodities after harvest, or to animals. Cabot
Corporation submitted a petition to EPA under the Federal Food, Drug,
and Cosmetic Act, as amended by the Food Quality Protection Act of 1996
requesting an exemption from the requirement of a tolerance. This
regulation eliminates the need to establish a maximum permissible level
for residues of dimethyl silicone polymer with silica; silane,
dichloromethyl-, reaction product with silica; and
hexamethyldisilizane, reaction product with silica.

DATES:  This regulation is effective September 29, 2000. Objections and
requests for hearings, identified by docket control number OPP-301055,
must be received by EPA on or before November 28, 2000.

ADDRESSES: Written objections and hearing requests may be submitted by
mail, in person, or by courier. Please follow the detailed instructions
for each method as provided in Unit VIII. of the SUPPLEMENTARY
INFORMATION. To ensure proper receipt by EPA, your objections and
hearing requests must identify docket control number OPP-301055 in the
subject line on the first page of your response.

FOR FURTHER INFORMATION CONTACT:  By mail: Vera Soltero, Registration
Division (7505C), Office of Pesticide Programs, Environmental
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460;
telephone number: (703) 308-9359 and e-mail address:
soltero.vera@epa.gov.

SUPPLEMENTARY INFORMATION:

[[Page 58400]]

I. General Information

A. Does this Action Apply to Me?

    You may be 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:

------------------------------------------------------------------------
                                                          Examples of
           Categories                 NAICS codes         Potentially
                                                       Affected Entities
------------------------------------------------------------------------
Industry                          111                 Crop production
                                  112                 Animal production
                                  311                 Food manufacturing
                                  32532               Pesticide
                                                       manufacturing
------------------------------------------------------------------------

    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 the table could also be
affected. The North American Industrial Classification System (NAICS)
codes have been provided to assist you and others in determining
whether or not this action might apply to certain entities. If you have
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 Additional Information, Including Copies of this
Document and Other Related Documents?

    1. Electronically. You may obtain electronic copies of this
document, and certain other related documents that might be available
electronically, from the EPA Internet Home Page at http://www.epa.gov/.
To access this document, on the Home Page select ``Laws and
Regulations,'' ``Regulations and Proposed Rules,'' and then look up the
entry for this document under the `` Federal Register--Environmental
Documents.'' You can also go directly to the Federal Register listings
at http://www.epa.gov/fedrgstr/.
    2. In person. The Agency has established an official record for
this action under docket control number OPP-301055. The official record
consists of the documents specifically referenced in this action, and
other information related to this action, including any information
claimed as Confidential Business Information (CBI). This official
record includes the documents that are physically located in the
docket, as well as the documents that are referenced in those
documents. The public version of the official record does not include
any information claimed as CBI. The public version of the official
record, which includes printed, paper versions of any electronic
comments submitted during an applicable comment period is available for
inspection in the Public Information and Records Integrity Branch
(PIRIB), Rm. 119, Crystal Mall #2, 1921 Jefferson Davis Hwy.,
Arlington, VA, from 8:30 a.m. to 4 p.m., Monday through Friday,
excluding legal holidays. The PIRIB telephone number is (703) 305-5805.

II. Background and Statutory Findings

    In the Federal Register of June 30, 2000 (65 FR 40632) (FRL-6592-
6), EPA issued a notice pursuant to section 408 of the Federal Food,
Drug, and Cosmetic Act (FFDCA), 21 U.S.C. 346a, as amended by the Food
Quality Protection Act (FQPA) (Public Law 104-170) announcing the
filing of pesticide petitions (PP 9E6017, PP 9E6018 and PP 9E6018) by
Cabot Corporation, 75 State Street, Boston, MA, 02109. This notice
included a summary of the petitions prepared by the petitioner. There
were no comments received in response to the notice of filing.
    The petition requested that 40 CFR 180.1001 (c) and (e) be amended
by revising the existing exemptions from the requirement of a tolerance
for residues of dimethyl silicone polymer with silica; silane,
dichloromethyl-, reaction product with silica; and
hexamethyldisilizane, reaction product with silica; CAS No. 67762-90-7,
CAS No. 68611-44-8, and CAS No. 68909-20-6, respectively.
    Section 408(c)(2)(A)(i) of the FFDCA allows EPA to establish an
exemption from the requirement for a tolerance (the legal limit for a
pesticide chemical residue in or on a food) only if EPA determines that
the tolerance is ``safe.'' Section 408(c)(2)(A)(ii) defines ``safe ''
to mean that ``there is a reasonable certainty that no harm will result
from aggregate exposure to the pesticide chemical residue, including
all anticipated dietary exposures and all other exposures for which
there is reliable information.'' This includes exposure through
drinking water and in residential settings, but does not include
occupational exposure. Section 408(b)(2)(C) requires EPA to give
special consideration to exposure of infants and children to the
pesticide chemical residue in establishing an exemption from the
requirement of a tolerance and to ``ensure that there is a reasonable
certainty that no harm will result to infants and children from
aggregate exposure to the pesticide chemical residue...'' and specifies
factors EPA is to consider in establishing an exemption.

III. Inert Ingredient Definition

    Inert ingredients are all ingredients that are not active
ingredients as defined in 40 CFR 153.125 and include, but are not
limited to, the following types of ingredients (except when they have a
pesticidal efficacy of their own): Solvents such as alcohols and
hydrocarbons; surfactants such as polyoxyethylene ploymers and fatty
acids; carriers such as clay and diatomaceous earth; thickeners such as
carrageenan and modified cellulose; wetting, spreading, and dispersing
agents; propellants in aerosol dispensers; microencapsulating agents;
and emulsifiers. The term ``inert'' is not intended to imply
nontoxicity; the ingredient may or may not be chemically active.
Generally, EPA has exempted inert ingredients from the requirement of a
tolerance based on the low toxicity of the individual inert
ingredients.

IV. Risk Assessment and Statutory Findings

    EPA establishes exemptions from the requirement of a tolerance only
in those cases where it can be clearly demonstrated that the risks from
aggregate exposure to pesticide chemical residues under reasonably
foreseeable circumstances will pose no appreciable risks to human
health. In order to determine the risks from aggregate exposure to
pesticide inert ingredients, the Agency considers the toxicity of the
inert in conjunction with possible exposure to residues of the inert
ingredient through food, drinking water, and through other exposures
that occur as a result of pesticide use in residential settings. If EPA
is able to determine that a finite tolerance is not necessary to ensure
that there is a reasonable certainty that no harm will result from
aggregate exposure to the inert ingredient, an exemption from the
requirement of a tolerance may be established.
    Consistent with section 408(b)(2)(D) of FFDCA, EPA has reviewed the
available scientific data and other relevant information in support of
this action and considered its validity, completeness and reliability
and the relationship of this information to human risk. EPA has also
considered available information concerning the variability of the
sensitivities of major identifiable subgroups of consumers, including
infants and children. In the case of certain chemical substances that
are defined as polymers, the Agency has established a set of criteria
to identify

[[Page 58401]]

categories of polymers that should present minimal or no risk. The
definition of a polymer is given in 40 CFR 723.250(b). The following
exclusion criteria for identifying these low risk polymers are
described in 40 CFR 723.250(d).
    1. The polymers, dimethyl silicone polymer with silica; silane,
dichloromethyl-, reaction product with silica; and
hexamethyldisilizane, reaction product with silica, are not cationic
polymers nor are they reasonably anticipated to become cationic
polymers in a natural aquatic environment.
    2. The polymers do contain as an integral part of their compostion
the atomic elements carbon, hydrogen, and oxygen.
    3. The polymers do not contain as an integral part of their
composition, except as impurities, any element other than those listed
in 40 CFR 723.250(d)(2)(ii).
    4. The polymers are neither designed nor can they be reasonably
anticipated to substantially degrade, decompose, or depolymerize.
    5. The polymers are manufactured or imported from monomers and/or
reactants that are already included on the TSCA Chemical Substance
Inventory or manufactured under an applicable TSCA section 5 exemption.
    6. The polymers are not water absorbing polymers with a number
average molecular weight (MW) greater than or equal to 10,000 daltons.
    Additionally, the polymers, dimethyl silicone polymer with silica;
silane, dichloromethyl-, reaction product with silica; and
hexamethyldisilizane, reaction product with silica, also meet as
required the following exemption criteria specified in 40 CFR
723.250(e).
    7. The polymers' number average MW of 1,100,000 daltons; 3,340,000
daltons; and 645,000 daltons, respectively is greater than or equal to
10,000 daltons. The polymer contains less than 2% oligomeric material
below MW 500 and less than 5% oligomeric material below MW 1,000.
    Thus, dimethyl silicone polymer with silica; silane,
dichloromethyl-, reaction product with silica; and
hexamethyldisilizane, reaction product with silica meet all the
criteria for a polymer to be considered low risk under 40 CFR 723.250.
Based on their conformance to the above criteria, no mammalian toxicity
is anticipated from dietary, inhalation, or dermal exposure to dimethyl
silicone polymer with silica; silane, dichloromethyl-, reaction product
with silica; and hexamethyldisilizane, reaction product with silica.

V. Aggregate Exposures

    For the purposes of assessing potential exposure under this
exemption, EPA considered that dimethyl silicone polymer with silica;
silane, dichloromethyl-, reaction product with silica; and
hexamethyldisilizane, reaction product with silica could be present in
all raw and processed agricultural commodities and drinking water, and
that non-occupational non-dietary exposure was possible. The number
average MW of dimethyl silicone polymer with silica; silane,
dichloromethyl-, reaction product with silica; and
hexamethyldisilizane, reaction product with silica are 1,100,000
daltons; 3,340,000 daltons; and 645,000 daltons, respectively.
Generally, a polymer of this size would be poorly absorbed through the
intact gastrointestinal tract or through intact human skin.
Additionally, since the polymer are not water-absorbing, it is expected
that respirable fractions would be cleared from the lungs. Since
dimethyl silicone polymer with silica; silane, dichloromethyl-,
reaction product with silica; and hexamethyldisilizane, reaction
product with silica conform to the criteria that identify a low risk
polymer, there are no concerns for risks associated with any potential
exposure scenarios that are reasonably foreseeable. The Agency has
determined that a tolerance is not necessary to protect the public
health.

VI. Cumulative Effects

    Section 408 (b)(2)(D)(v) of FFDCA requires that, when considering
whether to establish, modify, or revoke a tolerance or tolerance
exemption, the Agency consider ``available information '' concerning
the cumulative effects of a particular chemical's residues and ``other
substances that have a common mechanism of toxicity.'' The Agency has
not made any conclusions as to whether or not dimethyl silicone polymer
with silica; silane, dichloromethyl-, reaction product with silica; and
hexamethyldisilizane, reaction product with silica share a common
mechanism of toxicity with any other chemicals. However, dimethyl
silicone polymer with silica; silane, dichloromethyl-, reaction product
with silica; and hexamethyldisilizane, reaction product with silica
conform to the criteria that identify a low risk polymer. Due to the
expected lack of toxicity based on the above conformance, the Agency
has determined that a cumulative risk assessment is not necessary.

VII. Determination of Safety for U.S. Population

    Based on the conformance to the criteria used to identify a low
risk polymer, EPA concludes that there is a reasonable certainty of no
harm to the U.S. population from aggregate exposure to residues of
dimethyl silicone polymer with silica; silane, dichloromethyl-,
reaction product with silica; and hexamethyldisilizane, reaction
product with silica.

VIII. Determination of Safety for Infants and Children

    FFDCA section 408 provides that EPA shall apply an additional
tenfold margin of safety for infants and children in the case of
threshold effects to account for prenatal and postnatal toxicity and
the completeness of the data base unless EPA concludes that a different
margin safety will be safe for infants and children. Due to the
expected low toxicity of dimethyl silicone polymer with silica; silane,
dichloromethyl-, reaction product with silica; and
hexamethyldisilizane, reaction product with silica, EPA has not used a
safety factor analysis to assess the risk. For the same reasons the
additional tenfold safety factor is unnecessary.

IX. Other Considerations

A. Endocrine Disruptors

    There is no available evidence that dimethyl silicone polymer with
silica; silane, dichloromethyl-, reaction product with silica; and
hexamethyldisilizane, reaction product with silica are endocrine
disruptors.

B. Existing Exemptions from a Tolerance

    An exemption from tolerance under 40 CFR 180.1001(c) and (e) was
established for dimethyl silicone polymer with silica; silane,
dichloromethyl-, reaction product with silica; and
hexamethyldisilizane, reaction product with silica published in the
Federal Register of March 1, 2000, (65 FR 10946) (FRL-6490-9). The
following uses were exempted for both dimethyl silicone polymer with
silica and hexamethyldisilizane, reaction product with silica: moisture
barrier, anti-caking agent, anti-settling agent. This amendment to the
existing exemption adds thickening agent to the uses for dimethyl
silicone polymer with silica and hexamethyldisilizane, reaction product
with silica under 40 CFR 180.1001(c) and (e).
    The uses exempted for silane, dichloromethyl-, reaction product
with silica were: moisture barrier, anti-caking agent, anti-settling
agent, anti-

[[Page 58402]]

thickening agent. This final rule establishes that anti-thickening be
revised by deleting anti, so that the uses for silane, dichloromethyl-,
reaction product with silica under 40 CFR 180.1001(c) and (e) will read
as follows: moisture barrier, anti-caking agent, anti-settling agent,
thickening agent.

C. Analytical Enforcement Methodology

    An analytical method is not required for enforcement purposes since
the Agency is establishing an exemption from the requirement of a
tolerance without any numerical limitation.

D. International Tolerances

    The Agency is not aware of any country requiring a tolerance for
dimethyl silicone polymer with silica; silane, dichloromethyl-,
reaction product with silica; and hexamethyldisilizane, reaction
product with silica nor have any CODEX Maximum Residue Levels (MRLs)
been established for any food crops at this time.

X. Conclusion

    Accordingly, EPA finds that exempting residues of dimethyl silicone
polymer with silica; silane, dichloromethyl-, reaction product with
silica; and hexamethyldisilizane, reaction product with silica from the
requirement of a tolerance will be safe.

XI. Objections and Hearing Requests

    Under section 408(g) of the FFDCA, as amended by the FQPA, any
person may file an objection to any aspect of this regulation and may
also request a hearing on those objections. The EPA procedural
regulations which govern the submission of objections and requests for
hearings appear in 40 CFR part 178. Although the procedures in those
regulations require some modification to reflect the amendments made to
the FFDCA by the FQPA of 1996, EPA will continue to use those
procedures, with appropriate adjustments, until the necessary
modifications can be made. The new section 408(g) provides essentially
the same process for persons to ``object'' to a regulation for an
exemption from the requirement of a tolerance issued by EPA under new
section 408(d), as was provided in the old FFDCA sections 408 and 409.
However, the period for filing objections is now 60 days, rather than
30 days.

A. What Do I Need to Do to File an Objection or Request a Hearing?

    You must file your objection or request a hearing on this
regulation in accordance with the instructions provided in this unit
and in 40 CFR part 178. To ensure proper receipt by EPA, you must
identify docket control number OPP-301055 in the subject line on the
first page of your submission. All requests must be in writing, and
must be mailed or delivered to the Hearing Clerk on or before November
28, 2000.
    1. Filing the request. Your objection must specify the specific
provisions in the regulation that you object to, and the grounds for
the objections (40 CFR 178.25). If a hearing is requested, the
objections must include a statement of the factual issues(s) on which a
hearing is requested, the requestor's contentions on such issues, and a
summary of any evidence relied upon by the objector (40 CFR 178.27).
Information submitted in connection with an objection or hearing
request may be claimed confidential by marking any part or all of that
information as CBI. Information so marked will not be disclosed except
in accordance with procedures set forth in 40 CFR part 2. A copy of the
information that does not contain CBI must be submitted for inclusion
in the public record. Information not marked confidential may be
disclosed publicly by EPA without prior notice.
    Mail your written request to: Office of the Hearing Clerk (1900),
Environmental Protection Agency, 1200 Pennsylvania Ave., NW.,
Washington, DC 20460. You may also deliver your request to the Office
of the Hearing Clerk in Rm. M3708, Waterside Mall, 1200 Pennsylvania
Ave., NW., Washington, DC 20460. The Office of the Hearing Clerk is
open from 8 a.m. to 4 p.m., Monday through Friday, excluding legal
holidays. The telephone number for the Office of the Hearing Clerk is
(202) 260-4865.
    2. Tolerance fee payment. If you file an objection or request a
hearing, you must also pay the fee prescribed by 40 CFR 180.33(i) or
request a waiver of that fee pursuant to 40 CFR 180.33(m). You must
mail the fee to: EPA Headquarters Accounting Operations Branch, Office
of Pesticide Programs, P.O. Box 360277M, Pittsburgh, PA 15251. Please
identify the fee submission by labeling it ``Tolerance Petition Fees.''
    EPA is authorized to waive any fee requirement ``when in the
judgement of the Administrator such a waiver or refund is equitable and
not contrary to the purpose of this subsection.'' For additional
information regarding the waiver of these fees, you may contact James
Tompkins by phone at (703) 305-5697, by e-mail at tompkins.jim@epa.gov,
or by mailing a request for information to Mr. Tompkins at Registration
Division (7505C), Office of Pesticide Programs, Environmental
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460.
    If you would like to request a waiver of the tolerance objection
fees, you must mail your request for such a waiver to: James Hollins,
Information Resources and Services Division (7502C), Office of
Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania
Ave., NW., Washington, DC 20460.
    3. Copies for the Docket. In addition to filing an objection or
hearing request with the Hearing Clerk as described in Unit VIII.A.,
you should also send a copy of your request to the PIRIB for its
inclusion in the official record that is described in Unit I.B.2. Mail
your copies, identified by docket control number OPP-301055, to: Public
Information and Records Integrity Branch, Information Resources and
Services Division (7502C), Office of Pesticide Programs, Environmental
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460.
In person or by courier, bring a copy to the location of the PIRIB
described in Unit I.B.2. You may also send an electronic copy of your
request via e-mail to: opp-docket@epa.gov. Please use an ASCII file
format and avoid the use of special characters and any form of
encryption. Copies of electronic objections and hearing requests will
also be accepted on disks in WordPerfect 6.1/8.0 file format or ASCII
file format. Do not include any CBI in your electronic copy. You may
also submit an electronic copy of your request at many Federal
Depository Libraries.

B. When Will the Agency Grant a Request for a Hearing?

    A request for a hearing will be granted if the Administrator
determines that the material submitted shows the following: There is a
genuine and substantial issue of fact; there is a reasonable
possibility that available evidence identified by the requestor would,
if established resolve one or more of such issues in favor of the
requestor, taking into account uncontested claims or facts to the
contrary; and resolution of the factual issues(s) in the manner sought
by the requestor would be adequate to justify the action requested (40
CFR 178.32).

XII. Regulatory Assessment Requirements

    This final rule establishes an exemption from the tolerance
requirement under FFDCA section 408(d) in response to a petition
submitted to the Agency. The Office of Management and Budget (OMB) has
exempted these types of actions from review under Executive Order
12866, entitled Regulatory Planning and

[[Page 58403]]

Review (58 FR 51735, October 4, 1993). This final rule does not contain
any information collections subject to OMB approval under the Paperwork
Reduction Act (PRA), 44 U.S.C. 3501 et seq., or impose any enforceable
duty or contain any unfunded mandate as described under Title II of the
Unfunded Mandates Reform Act of 1995 (UMRA) (Public Law 104-4). Nor
does it require any prior consultation as specified by Executive Order
13084, entitled Consultation and Coordination with Indian Tribal
Governments (63 FR 27655, May 19, 1998); special considerations as
required by Executive Order 12898, entitled Federal Actions to Address
Environmental Justice in Minority Populations and Low-Income
Populations (59 FR 7629, February 16, 1994); or require OMB review or
any Agency action under Executive Order 13045, entitled Protection of
Children from Environmental Health Risks and Safety Risks (62 FR 19885,
April 23, 1997). This action does not involve any technical standards
that would require Agency consideration of voluntary consensus
standards pursuant to section 12(d) of the National Technology Transfer
and Advancement Act of 1995 (NTTAA), Public Law 104 -113, section 12(d)
(15 U.S.C. 272 note). Since tolerances and exemptions that are
established on the basis of a petition under FFDCA section 408(d), such
as the exemption in this final rule, do not require the issuance of a
proposed rule, the requirements of the Regulatory Flexibility Act (RFA)
(5 U.S.C. 601 et seq.) do not apply. In addition, the Agency has
determined that this action will not have a substantial direct effect
on States, on the relationship between the national government and the
States, or on the distribution of power and responsibilities among the
various levels of government, as specified in Executive Order 13132,
entitled Federalism (64 FR 43255, August 10, 1999). Executive Order
13132 requires EPA to develop an accountable process to ensure
``meaningful and timely input by State and local officials in the
development of regulatory policies that have federalism implications.''
``Policies that have federalism implications '' is defined in the
Executive Order to include regulations that have `` substantial direct
effects on the States, on the relationship between the national
government and the States, or on the distribution of power and
responsibilities among the various levels of government.'' This final
rule directly regulates growers, food processors, food handlers and
food retailers, not States. This action does not alter the
relationships or distribution of power and responsibilities established
by Congress in the preemption provisions of FFDCA section 408(n)(4).

XIII. Submission to Congress and the Comptroller General

    The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the
Small Business Regulatory Enforcement Fairness Act of 1996, generally
provides that before a rule may take effect, the agency promulgating
the rule must submit a rule report, which includes a copy of the rule,
to each House of the Congress and to the Comptroller General of the
United States. EPA will submit a report containing this rule and other
required information to the U.S. Senate, the U.S. House of
Representatives, and the Comptroller General of the United States prior
to publication of this rule in the Federal Register. This rule is not a
``major rule '' as defined by 5 U.S.C. 804(2).

List of Subjects in 40 CFR Part 180

    Environmental protection, Administrative practice and procedure,
Agricultural commodities, Pesticides and pests, Reporting and
recordkeeping requirements.

    Dated: September 19, 2000.

James Jones,

Director, Registration Division, Office of Pesticide Programs.

    Therefore, 40 CFR chapter I is amended as follows:

PART 180-- [AMENDED]

    1. The authority citation for part 180 continues to read as
follows:

    Authority:  21 U.S.C. 321(q), (346a) and 371.

    2. In Sec. 180.1001 the tables in paragraphs (c) and (e) are
amended by revising the following entries to read as follows:

Sec. 180.1001  Exemptions from the requirement of a tolerance.

* * * * *
    (c) *  *  *

------------------------------------------------------------------------
        Inert ingredients               Limits               Uses
------------------------------------------------------------------------
         *        *        *        *        *        *        *
Dimethyl silicone polymer with    ..................  Moisture barrier,
 silica, Minimum number average    ..                  anti-caking
 molecular weight (in amu)                             agent, anti-
 1,100,000 daltons, CAS Reg. No.                       settling agent,
 67762-90-7                                            thickening agent
         *        *        *        *        *        *        *
Hexamethyldisilizane, reaction    ..................  Moisture barrier,
 product with silica, minimum      ..                  anti-caking
 number average molecular weight                       agent, anti-
 (in amu) 645,000 daltons, CAS                         settling agent,
 Reg. No. 68909-20-6                                   thickening agent
         *        *        *        *        *        *        *
Silane, dichloromethyl-,          ..................  Moisture barrier,
 reaction product with silica      ..                  anti-caking
 minimum number average                                agent, anti-
 molecular weight (in amu)                             settling agent,
 3,340,000 daltons, CAS Reg. No.                       thickening agent
 68611-44-9
         *        *        *        *        *        *        *
------------------------------------------------------------------------

    (e) *  *  *

[[Page 58404]]

------------------------------------------------------------------------
        Inert ingredients               Limits               Uses
------------------------------------------------------------------------
         *        *        *        *        *        *        *
Dimethyl silicone polymer with    ..................  Moisture barrier,
 silica, Minimum number average    ..                  anti-caking
 molecular weight (in amu)                             agent, anti-
 1,100,000 daltons, CAS Reg. No.                       settling agent,
 67762-90-7                                            thickening agent
         *        *        *        *        *        *        *
Hexamethyldisilizane, reaction    ..................  Moisture barrier,
 product with silica, Minimum      ..                  anti-caking
 number average molecular weight                       agent, anti-
 (in amu) 645,000 daltons, CAS                         settling agent,
 Reg. No. 68909-20-6                                   thickening agent
         *        *        *        *        *        *        *
Silane, dichloromethyl-,          ..................  Moisture barrier,
 reaction product with silica,     ..                  anti-caking
 Minimum number average                                agent, anti-
 molecular weight (in amu)                             settling agent,
 3,340,000 daltons, CAS Reg. No.                       thickening agent
 68611-44-9
         *        *        *        *        *        *        *
------------------------------------------------------------------------

[FR Doc. 00-25050 Filed 9-28-00]
BILLING CODE 6560-50-S 

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