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EPA REGISTRATION DIVISION CO MPANY NOTICE OF FILING FOR

PESTICIDE PETITIONS PUBLISHED IN THE FEDERAL REGISTER

EPA Registration Division contact: [insert name and telephone number with area code]

INSTRUCTIONS: Please utilize this outline in p reparing the pesticide petition. In

cases where the outline element does not apply, please insert “NA-Remove” and

maintain the outline. Please do not chan ge the margins, font, or format in your pesticide petition. Simply replace the instructions that appear in green , i.e., “ [insert company name] ,” with the information specific to your action.

TEMPLATE:

Wacker Chemical Corporation

[Insert petition number]

EPA has received a pesticide petition (PP 9E7634) from Wacker Chemical Corporation, 3301 Sutton Rd., Adrian, MI. 49221-9397 proposing, pursuant to section 408(d) of the Federal Food, Drug, and Cosme tic Act (FFDCA), 21 U.S.C. 346a(d), to amend 40 CFR part 180.

2. to establish an exemption from the requirement of a tolerance for

Tetraethoxysilane, polymer with hexamethyldisiloxane with a minimum number average molecular weight of (in AMU) of 2,500 CAS Number 104133-09-7 in or on the all raw agricultural commoditie s . EPA has determined that the petition contains data or information regarding the el ements set forth in se ction 408 (d)(2) of FDDCA; however, EPA has not fully evaluated the sufficiency of the submitted data at this time or whether the data supports gran ting of the petition. Additional data may be needed before EPA rules on the petition.

A. Residue Chemistry NA-Remove Requirements for data on residue chemistr y are not applicable to a request to establish an exemption from requirement of a tolerance, based on conformance to specific criteria that identify categories of polymers that should present minimal or

no risk

1. Plant metabolism. NA-Remove

2. Analytical method. NA-Remove2

3. Magnitude of residues. NA-Remove

B. Toxicological Profile NA-Remove Requirements for data on Toxicological prop erties are not applicable to a request to establish an exemption from requirement of a tolerance, based on conformance to specific criteria that identify categories of polymers that should present minimal or

no risk

Tetraethoxysilane, polymer with hexamet hyldisiloxane, minimum number average molecular weight (in AMU) 2,500 conforms to the definition of a polymer given in 40 CFR 723(b) and meets the criteria that a re used to identify low risk polymers. under the TSCA Polymer Exemption Guidelines.

1. The polymer is not a cationic polymer nor is it reasonably anticipated to become a cationic polymer in the aquatic environment.

Justification: Tetraethoxysilane, polymer with hexamethyldisiloxane contains no cationic functional groups, nor any moiety that can potentially produce a cationic

group.

2. The polymer does contain as an integr al part of its composition the atomic elements carbon, hydrogen, oxygen and silicon.

Justification: Tetraethoxysilane, polymer with hexamethyldisiloxane contains four of the permitted elements (carbon, hydrogen, nitrogen, oxygen, sulfur and silicon), and does not contain any of the elements of concern (fluoride, lithium, boron, phosphorus, etc.).

3. The polymer does not contain as an inte gral part of its composition except as impurities, any element other than those listed in 40CFR 723.250(d)(2)(ii).

Justification: Tetraethoxysilane, polymer wi th hexamethyldisiloxane is produced by reacting two compounds Tetatraethoxy silane (AKA Tetraethyl silicate) with a

molecular formula C8H20O4Si with Hexa methyldisiloxane with a molecular formula C6H18OSi2. Neither starting materi al contains, except as impurites, any

elements not listed in 40CFR 723.250(d)(2)(ii).

4. The polymer is neither designed nor can it be reasonably anticipated to substantially degrade, decompose or depolymerize.

Justification: Tetraethoxysilane, polymer with hexamethyldisiloxane contains only H-C, C-Si, C-O and Si-O bo nds, none of which are unstable (as evidenced by the known stability of polysiloxanes and s ilicones) and therefore the polymer will be

stable.3

5. The polymer is manufactured or imported from monomers and or reactants that are already listed on the TSCA Chemical Substance Inventory or manufactured under and applicable TSCA Section 5 exemption.

Justification: Tetraethoxy silane CAS Number 78-10-4 and Hexamethyldisiloxane CAS Number 107-46-0 are both listed on the TSCA Inventory.

6. The polymer is not a water-absorbing polymer with a minimum number average molecular weight greater than or equal to 10,000 AMU.

Justification: The polymer is non-ionic, does not contain any significant hydrophilic groups and like most silicone resins is expected to be relatively hydrophobic. The number average molecular weight is only 2,500 AMU which is well under the 10,000 AMU upper limit.

7. Tetraethoxysilane, polymer with hexamethy ldisiloxane meets the criteria specified in 40CFR 723.250(e)(1).

Justification: The minimum number average molecular weight (Mn) of the polymer is greater than 1000 AMU but less than 10,000 AMU. The weight fraction less than 500 AMU is less than 10% and the weight fr action less than 1,000 AMU is less than

25%.

This polymer is already listed in 40CFR 180.960, but with a higher minimum number average molecular weight limit ( 6,500 AMU). At our proposed lower (Mn) of limit of 2,500 this polymer would still meet all of the cr iteria for a polymer to be

considered low risk under 40CFR 723.250. Based on its conformance to these criteria no mammalian toxicity is anticipate d from dietary ingest ion, inhalation or dermal exposure to Tetraethoxysilane, polymer with hexamethyldisiloxane .

1. Acute toxicity

. NA- Remove

2. Genotoxicty. NA-Remove

3. Reproductive and developmental toxicity. NA-Remove

4. Subchronic toxicity. NA-Remove

5. Chronic toxicity. NA-Remove]

6. Animal metabolism. NA-Remove

7. Metabolite toxicology

. NA-Remove

8. Endocrine disruption

. NA-Remove4

C. Aggregate Exposure For the purposes of assessing potential exposure under this exemption, Tetraethoxysilane, polymer with hexamethy ldisiloxane could be considered to be present in all raw and processed agricultur al commodities and drinking water, and non-occupational non-dietary exposure is possible. The minimum number average molecular weight of Tetraethoxysilane, po lymer with hexamethyldisiloxane is 2,500 AMU. Generally, a polymer of this size woul d be poorly absorbed through the intact gastrointestinal tract or through intact human skin. Since Tetraethoxysilane, polymer with hexamethyldisiloxane conforms to the criteria that identify a low risk polymer, there should be no concerns for risks associated with any reasonably foreseeable potential exposure scenarios. A tolerance should not be necessary to protect public health.

1. Dietary exposure. NA-Remove

i. Food. NA-Remove

ii. Drinking water. NA-Remove

2. Non-dietary exposure

. NA-Remove

D. Cumulative Effects

Section 408(b)(2)(D)(v) of FFDCA requi res that, when considering whether to establish, modify, or revoke a tolera nce or tolerance exemption, the Agency consider "available information" concerning the cumulative effects of a particular

chemical's residues and "other substan ces that have a common mechanism of toxicity.". Wacker Chemical Corporation does not have any available data indicating that Tetraethoxysilane, poly mer with hexamethyldisiloxane has a common mechanism of toxicity with oth er substances Tetraethoxysilane, polymer with hexamethyldisiloxane is also not likely to produce any toxic metabolite produced by other substances. For the purposes of this tolerance exemption Tetraethoxysilane, polymer with hexamethyldisiloxane should not be assumed to have a common mechanism of toxicity with other substances.

E. Safety Determination

1. U.S. population. NA-Remove

2. Infants and children

. Section 408 of FFDCA provides that EPA shall apply an additional tenfold margin of safety for infants and child ren in the case of threshold effects to account for pre-na tal and post-natal toxicity and the completeness of the data base unless EPA conc ludes that a different margin of safety

will be safe for infants and children. Due to the expected low toxicity of Tetraethoxysilane, polymer with hexamethyld isiloxane a safety factor analysis to5

assess specific risk to infants and child ren should not be required. For the same

reasons the additional tenfold safety factor is unnecessary.

F. International Tolerances

Wacker Chemical Corporation is no t aware of any country requiring a tolerance for Tetraethoxysila ne, polymer with hexamethyldisiloxane nor have any CODEX Maximum Residue Levels (MRLs) b een established for any food crops at this time,