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EPA REGISTRATION DIVISION COMPANY NOTICE OF FILING FOR 

PESTICIDE PETITIONS PUBLISHED IN THE FEDERAL REGISTER 

EPA Registration Division contact: William Cutchin 703-305-7990

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

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

maintain the outline. Please do not change 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

IN-10890

EPA has received a pesticide petition (IN-10890) from Wacker Chemical 

Corporation, 3301 Sutton Rd., Adrian, ML 49221-9397 requesting, 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

siloxanes and silicones, 3-bydroxypropyl Me, ethoxylated (CAS No. 69430-50-8), under 

40 CFR180.910 when used as an inert ingredient for the modification of surface tension

properties, serving as an anti-foaming agent in pesticide formulations.

EPA has determined that the petition contains data or information regarding the 

elements set forth in section 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 

granting of the petition. Additional data may be needed before EPA rules on the petition.

A. Residue Chemistry

Requirements for data on residue chemistry 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 minimum or no 

risk.

1. Plant metabolism. NA-Remove

2. Analytical method. NA-Remove

3. Magnitude of residues. NA-Remove

B. Toxicological Profile
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Requirements for data on toxicological properties 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.

The polymer, siloxanes and silicones, 3-hydroxypropyl Me, ethoxylated is

structurally similar to other polymers listed within the Methylated Silicone category

especially the following CAS numbers: 67674-67-3, 67762-85-0, 67762-87-2, 68440-66-

4, 68937-54-2, 68938-54-5 and 117272-76-1 which were included in the EPA 2006

Methylated Silicones inert ingredient reassessment review.

1. The polymer is not a cationic polymer nor is it reasonably anticipated to become a

cationic polymer in the aquatic environment.

Justification: The polysiloxane contains no cationic functional groups, nor any moiety 

that can potentially produce a cationic group.

2. The polymer contains as an integral part of its composition the atomic elements

carbon, hydrogen, oxygen and silicon.

Justification: siloxanes and silicones, 3-hydroxypropyl Me, ethoxylated contains four (C, 

H, O and Si) 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 integral part of its composition except as 

impurities, any element other than those listed in 40CFR 723.250(d)(2)(ii).

Justification: This polymer siloxanes and silicones, 3-hydroxypropyl Me, ethoxylated is 

not expected to contain, except as trace impurities, any of the 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: The chemical bonds within this polymer are the same as those present in 

other siloxanes and silicones, none of which are unstable (as evidenced by the known 

stability of silicone polymers) and therefore this polymer is expected to be stable.

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: CAS 69430-50-8 is listed on the TSCA Inventory, and both starting

reactants: Siloxanes and silicones, Me hydrogen CAS 63148-57-2 and ethoxylated allyl 
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alcohol (aka polyethylene glycol, mono-allyl ether) CAS 27274-31-3, are 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, the calculated average molecular weight is well 

under the 10,000 AMU upper limit.

7. The polymer meets the criteria specified in 40CFR 723.250(e)(1).

Justification: The average molecular weight of the polymer is expected to be greater than 

1000 AMU but less than 10,000 AMU. This polymer is formed as a by-product in 

combination with other polymers made during hydrosilylation reactions between

hydrogen functional polysiloxanes and polyglycol ethers, these polymers are not typically 

removed or separated from the reaction mixture. Based on a structural formula analysis 

the calculated average molecular weight is 2067 AMU using a typical empirical formula 

of C86Hi8304iSi7.

The polymer should be considered a low risk under 40CFR 723.250. Based on its 

conformance to these criteria no mammalian toxicity is anticipated from dietary

ingestion, inhalation or dermal exposure

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-Remove

C. Aggregate Exposure

For the purposes of assessing potential exposure under this exemption, siloxanes 

and silicones, 3-hydroxypropyl Me, ethoxylated could be considered to be present in all 

raw and processed agricultural commodities and drinking water, and non-occupational 

non-dietary exposure is possible. Generally, a silicone polymer of this size would be 

poorly absorbed through the intact gastrointestinal tract or through intact human skin. 

Since siloxanes and silicones, 3-hydroxypropyl Me, ethoxylated is expected to behave in 

a similar manner to other methylated silicones and would conform to the criteria that 
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identify a low risk polymer, there should not be any significant concerns for risks 

associated with 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 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.".

Wacker Chemical Corporation does not have any available data indicating that 

siloxanes and silicones, 3-hydroxypropyl Me, ethoxylated has any common mechanism 

of toxicity with other substances, and is not likely to produce any toxic metabolites. For 

the purposes of this tolerance exemption siloxanes and silicones, 3-hydroxypropyl Me, 

ethoxylated 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 children in the case of threshold effects 

to account for pre-natal and post-natal toxicity and the completeness of the data base 

unless EPA concludes that a different margin of safety will be safe for infants and 

children.

Due to the expected low toxicity of siloxanes and silicones, 3-hydroxypropyl Me, 

ethoxylated a safety factor analysis to assess specific risk to infants and children should 

not be required. For the same reasons the additional tenfold safety factor is unnecessary.

F. International Tolerances

Wacker Chemical Corporation is not aware of any country requiring a tolerance 

for Siloxanes and Silicones, 3-hydroxypropyl Me, ethoxylated nor have any CODEX 

Maximum Residue Levels (MRLs) been established for any food crops at this time.
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