>vEPA

February 2022

United States	Office of Chemical Safety and

Environmental Protection Agency	Pollution Prevention

Final Scope of Risk Evaluation for
Octamethylcyclotetra- siloxane (D4)

Supplemental File:

Data Extraction and Data Evaluation Tables
for Physical and Chemical Property Studies for D4 Degradants

CH-

HO—Si	OH

I

CHo

(CASRN 1066-42-8)

OH

H,C	Si	CH:

H3C

^Si

0	\

1	ch3

H3C	Si	CH3

OH

(CASRN 3663-50-1)

CH?
HO /

Si\

/ O

h3c |

H3C	Si	CH3

OH

(CASRN 1118-15-6)

CH,

HO /

Si

/ 0
H3C

H,C	Si	CH^

I ch3

°\ /

Si.

/ o
H3C |

H3C	Si	CH3

OH

(CASRN 3081-07-0)

February 2022


-------
Table of Contents

Dimethylsilanediol (CASRN 1066-42-8) Data Extraction Tables	6

Table 1. Physical State Study Summary	6

Table 2. Physical Properties Study Summary	6

Table 3. Melting Point Study Summary	6

Table 4. Boiling Point Study Summary	6

Table 5. Density Study Summary	6

Table 6. Vapor Pressure Study Summary	7

Table 7. Vapor Density Study Summary	7

Table 8. Water Solubility Study Summary	7

Table 9. Octanol Water Coefficient (logKow) Study Summary	7

Table 10. Henry's Law Constant Study Summary	8

Table 11. Flash Point Study Summary	8

Table 12. Auto Flammability Study Summary	8

Table 13. Viscosity Study Summary	8

Table 14. Refractive Index Study Summary	8

Table 15. Dielectric Constant Study Summary	8

EPI Suite™ Model Outputs	9

Data Evaluation Tables	12

Elsevier (2021). Reaxys: physical-chemical property data for dimethylsilanediol. CAS

Registry Number: 1066-42-8; HERO ID: 7995011	 12

Elsevier (2021). Reaxys: physical-chemical property data for dimethylsilanediol. CAS

Registry Number: 1066-42-8; HERO ID: 7995011	 13

Elsevier (2021). Reaxys: physical-chemical property data for dimethylsilanediol. CAS

Registry Number: 1066-42-8; HERO ID: 7995011	 14

Rsc (2021). ChemSpider: Dimethylsilanediol. HERO ID: 7999339	 15

Elsevier (2021). Reaxys: physical-chemical property data for dimethylsilanediol. CAS

Registry Number: 1066-42-8. HERO ID: 7995011	 16

U.S.EPA (2021). Chemistry dashboard information for Dimethylsilanediol. CAS registry

number: 1066-42-8. HERO ID: 7996867	 17

U.S. EPA. (2021). Chemistry dashboard information for Dimethylsilanediol. CAS registry

number: 1066-42-8; HERO ID: 7996867	 18

U.S. EPA (2021). Pubchem: Dimethylsilanediol. CAS registry number: 1066-42-8. HERO

ID: 7998093 	 19

Xu, S. and B. Kropscott (2012). Method for simultaneous determination of partition
coefficients for cyclic volatile methylsiloxanes and dimethylsilanediol. Analytical

Chemistry 84(4): 1948-1955	21

Elsevier (2021). Reaxys: physical-chemical property data for dimethylsilanediol. CAS

Registry Number: 1066-42-8. HERO ID: 7995011	22

U.S. EPA (U.S. Environmental Protection Agency). (2012). Estimation Programs Interface
Suite™ for Microsoft® Windows, v 4.11 [Computer Program], Washington, DC. HERO
ID:2347246	23

Tetramethyldisiloxanediol (CASRN 1118-15-6) Data Extraction Tables	24

Table 1. Physical State Study Summary	24

Page 2 of 63


-------
Table 2. Physical Properties Study Summary	24

Table 3. Melting Point Study Summary	24

Table 4. Boiling Point Study Summary	24

Table 5. Density Study Summary	25

Table 6. Vapor Pressure Study Summary	25

Table 7. Vapor Density Study Summary	25

Table 8. Water Solubility Study Summary	25

Table 9. Octanol Water Coefficient (logKow) Study Summary	26

Table 10. Henry's Law Constant Study Summary	26

Table 11. Flash Point Study Summary	26

Table 12. Auto Flammability Study Summary	26

Table 13. Viscosity Study Summary	26

Table 14. Refractive Index Study Summary	26

Table 15. Dielectric Constant Study Summary	26

EPI Suite™ Model Outputs	27

Data Evaluation Tables	30

Elsevier (2021). Reaxys: physical-chemical property data for tetramethyl-l,3-disiloxanediol.

CAS Registry Number: 1118-15-6. HERO ID: 7994661 	 30

Elsevier (2021). Reaxys: physical-chemical property data for tetramethyl-l,3-disiloxanediol.

CAS Registry Number: 1118-15-6. HERO ID: 7994661 	 31

Elsevier (2021). Reaxys: physical-chemical property data for tetramethyl-l,3-disiloxanediol.

CAS Registry Number: 1118-15-6. HERO ID: 7994661 	 32

Haynes, W. M. (2014). CRC Handbook of Chemistry and Physics l,l,3,3-Tetramethyl-l,3-

disiloxanediol. Boca Raton, FL, CRC Press. Taylor & Francis Group. HERO ID: 7998725 33
Elsevier (2021). Reaxys: physical-chemical property data for tetramethyl-l,3-disiloxanediol.

CAS Registry Number: 1118-15-6. HERO ID: 7994661 	 34

Haynes, W. M. (2014). CRC Handbook of Chemistry and Physics l,l,3,3-Tetramethyl-l,3-

disiloxanediol. Boca Raton, FL, CRC Press. Taylor & Francis Group. HERO ID: 7998725 35
Elsevier (2021). Reaxys: physical-chemical property data for tetramethyl-l,3-disiloxanediol.

CAS Registry Number: 1118-15-6. HERO ID: 7994661 	 36

U.S. EPA (2021). Chemistry dashboard information for 1,3-Disiloxanediol, 1,1,3,3-

tetramethyl-. CAS registry number: 1118-15-6. HERO ID: 7995923	 37

U.S. EPA (2021). Chemistry dashboard information for 1,3-Disiloxanediol, 1,1,3,3-

tetramethyl-. CAS registry number: 1118-15-6. HERO ID: 7995923	 38

NLM (2021). Pubchem: 1,3-Disiloxanediol, 1,1,3,3-tetramethyl-. CAS registry number: 1118-

15-6	39

Elsevier (2021). Reaxys: physical-chemical property data for tetramethyl-l,3-disiloxanediol.

CAS Registry Number: 1118-15-6. HERO ID: 7994661 	40

U.S. EPA (U.S. Environmental Protection Agency). (2012). Estimation Programs Interface
Suite™ for Microsoft® Windows, v 4.11 [Computer Program], Washington, DC. HERO
ID:2347246	41

Hexamethyltrisiloxanediol (CASRN 3663-50-1) Data Extraction Tables	42

Table 1. Physical State Study Summary	42

Table 2. Physical Properties Study Summary	42

Table 3. Melting Point Study Summary	42

Table 4. Boiling Point Study Summary	42

Table 5. Density Study Summary	42

Page 3 of 63


-------
Table 6. Vapor Pressure Study Summary	42

Table 7. Vapor Density Study Summary	42

Table 8. Water Solubility Study Summary	42

Table 9. Octanol Water Coefficient (logKow) Study Summary	43

Table 10. Henry's Law Constant Study Summary	43

Table 11. Flash Point Study Summary	43

Table 12. Auto Flammability Study Summary	43

Table 13. Viscosity Study Summary	43

Table 14. Refractive Index Study Summary	43

Table 15. Dielectric Constant Study Summary	43

EPI Suite™ Model Outputs	44

Data Evaluation Tables	47

Elsevier (2021). Reaxys: physical-chemical property data for 1,1,3,3,5,5-

hexamethyltrisiloxane-l,5-diol. CAS Registry Number: 3663-50-1. HERO ID: 7992314.... 47
Elsevier (2021). Reaxys: physical-chemical property data for 1,1,3,3,5,5-

hexamethyltrisiloxane-l,5-diol. CAS Registry Number: 3663-50-1. HERO ID: 7992314.... 48
Elsevier (2021). Reaxys: physical-chemical property data for 1,1,3,3,5,5-

hexamethyltrisiloxane-l,5-diol. CAS Registry Number: 3663-50-1. HERO ID: 7992314.... 49
Elsevier (2021). Reaxys: physical-chemical property data for 1,1,3,3,5,5-

hexamethyltrisiloxane-l,5-diol. CAS Registry Number: 3663-50-1. HERO ID: 7992314.... 50
U.S. EPA (U.S. Environmental Protection Agency). (2012). Estimation Programs Interface
Suite™ for Microsoft® Windows, v 4.11 [Computer Program], Washington, DC. HERO

ID:2347246	 51

Octamethyltetrasiloxanediol (CASRN 3081-07-0) Data Extraction Tables	52

Table 1. Physical State Study Summary	52

Table 2. Physical Properties Study Summary	52

Table 3. Melting Point Study Summary	52

Table 4. Boiling Point Study Summary	52

Table 5. Density Study Summary	52

Table 6. Vapor Pressure Study Summary	52

Table 7. Vapor Density Study Summary	52

Table 8. Water Solubility Study Summary	53

Table 9. Octanol Water Coefficient (logKow) Study Summary	53

Table 10. Henry's Law Constant Study Summary	53

Table 11. Flash Point Study Summary	53

Table 12. Auto Flammability Study Summary	53

Table 13. Viscosity Study Summary	53

Table 14. Refractive Index Study Summary	53

Table 15. Dielectric Constant Study Summary	53

EPI Suite™ Model Outputs	54

Data Evaluation Tables	57

Elsevier (2021). Reaxys: physical-chemical property data for 1,1,3,3,5,5,7,7-

octamethyltetrasiloxane-l,7-diol. CAS Registry Number: 3081-07-0. HERO ID: 7991715 . 57
Elsevier (2021). Reaxys: physical-chemical property data for 1,1,3,3,5,5,7,7-

octamethyltetrasiloxane-l,7-diol. CAS Registry Number: 3081-07-0. HERO ID: 7991715 . 58

Page 4 of 63


-------
Elsevier (2021). Reaxys: physical-chemical property data for 1,1,3,3,5,5,7,7-

octamethyltetrasiloxane-l,7-diol. CAS Registry Number: 3081-07-0. HERO ID: 7991715 . 59
Elsevier (2021). Reaxys: physical-chemical property data for 1,1,3,3,5,5,7,7-

octamethyltetrasiloxane-l,7-diol. CAS Registry Number: 3081-07-0. HERO ID: 7991715 . 60
Elsevier (2021). Reaxys: physical-chemical property data for 1,1,3,3,5,5,7,7-

octamethyltetrasiloxane-l,7-diol. CAS Registry Number: 3081-07-0. HERO ID: 7991715 61
U.S. EPA (U.S. Environmental Protection Agency). (2012). Estimation Programs Interface
Suite™ for Microsoft® Windows, v 4.11 [Computer Program], Washington, DC. HERO
ID:2347246	 62

Page 5 of 63


-------
Dimetliy 1 silanediol (CASRN 1066-42-8) Data Extraction Tables

Table 1. Physical State Study Summary

Study Type

Result

Comments

Affiliated Reference

Data Quality
Evaluation
Results

Experimental

2 values reported in Reaxys:
crystal phase - interplanar
spacing and leafs



(Elsevier. 202lc)

High

Table 2. Physical Properties Study Summary
No Physical Properties data were identified for this chemical.

Table 3. Melting Point Study Summary

Study Type

Substance
Purity

Result

Comments

Affiliated
Reference

Data Quality
Evaluation
Results

Experimental

NR

94.5-101 °C

10 values reported in Reaxys; the test substance
was dissolved in a solvent for 6 values.
Decomposition was reported at 99-100 °C.

(Elsevier. 202lc)

High

Table 4. Boiling Point Study Summary
No Boiling Point data were identified for this chemical.

Table 5. Density Study Summary

Study Type

Study
Details

Reference
Substance

Temperature

Result

Comments

Affiliated
Reference

Data Quality
Evaluation Results

Experimental







1.095-1.099 g/cm3

1 value reported
in Reaxys

(Elsevier. 2021c)

High

Experimental







0.97 g/ml.

NR

(RSC. 2021)

Medium

Page 6 of 63


-------
Table 6. Vapor Pressure Study Summary

No Vapor Pressure data were identified for this chemical.

Table 7. Vapor Density Study Summary

No Vapor Density data were identified for this chemical.

Study Type

Substance
Purity

Temperature

pH

Analytical
Method

Result

Comments

Affiliated Reference

Data Quality
Evaluation Results

Experimental

NR

25 °C

NR



2450 g/L

2 values reported in Reaxys;
temperature reported for one
value only

(Elsevier. 2021c)

High

Experimental

NR

NR

NR



11.0 M

Equivalent to 1,010,000
mg/I. based on MW 92.17

g/mol

(U.S. EPA. 2021b)

High

Experimental

NR

NR

NR



10.8 M

Equivalent to 995,000 mg/L
based on MW
92.17 g/mol

(U.S. EPA. 2021b)

High

Experimental

NR

NR

NR



10.85 M

Equivalent to
117.7 mg/I, based on MW
92.17 g/mol

(NLM. 2021b)

High

Table 9 Octanol Water Coefficient CloeKow"! Studv Summary

Study Type

Substance
Purity

Temperature

pH

Other Study Details
(Amounts of Substance
Liquid Phases)

Result

Comments

Affiliated References

Data Quality
Evaluation Results

Experimental

NR

20.1

NR

NR

-0.41 ±

0.10

1 value reported in
Reaxys

(Elsevier. 2021c) and
(Xu and Kropscott. 2012)

High

Page 7 of 63


-------
Table 10. Henry's Law Constant Study Summary

Study Type

Substance
Purity

Temperature

Result

Comments

Affiliated Reference

Data Quality
Evaluation
Results

Experimental

98.1%

radiochemical
purity

20.1 °C

-6.84

log Kaw = -6.84 ± 0.34; Air =
1 x 10 5 mg/L; W ater = 70.0 mg/L

(Xu and KroDSCOtt.
2012)

High

Table 11. Flash Point Study Summary

No Flash Point data were identified for this chemical.

Table 12. Auto Flammability Study Summary
No Autoflammability data were identified for this chemical.

Table 13. Viscosity Study Summary
No Viscosity data were identified for this chemical.

Table 14. Refractive Index Study Summary

Study Type

Apparatus

Result

Comments

Affiliated
Reference

Data Quality
Evaluation
Results

Experimental

25 °C

1.444-1.456

2 values were reported in Reaxys; 1.444-1.448
(n2) and 1.452-1.456 (nl), 589.3 nm

(Elsevier. 202 lc)

High

Table 15. Dielectric Constant Study Summary
No Dielectric Constant data were identified for this chemical.

Page 8 of 63


-------
EPI Suite1M Model Outputs
(U.S. EPA. 2012)

SMILES : [Si](0)(0)(C)C
CHEM : DIMETHYLSILANEDIOL
MOL FOR: C2 H8 02 Sil
MOL WT : 92.17

	EPI SUMMARY (v4.11)	

Physical Property Inputs:

Log Kow (octanol-water): -0.41

Boiling Point (°C):	

Melting Point (°C):	

Vapor Pressure (mm Hg):	

Water Solubility (mg/L): 9.95E+005
Henry LC (atm-m3/mole):	

Log Octanol-Water Partition Coef (SRC):

Log Kow (KOWWIN vl.68 estimate) = -0.41

Boiling Pt, Melting Pt, Vapor Pressure Estimations (MPBPVP vl.43):
Boiling Pt (°C): 184.32 (Adapted Stein & Brown method)

Melting Pt (°C): -18.70 (Mean or Weighted MP)

VP(mm Hg, 25 °C): 0.136 (Mean VP of Antoine & Grain methods)

VP (Pa, 25 °C): 18.1 (Mean VP of Antoine & Grain methods)

Water Solubility Estimate from Log Kow (WSKOW vl.42):

Water Solubility at 25 °C (mg/L): 2.753E+005
log Kow used: -0.41 (user entered)
no-melting pt equation used

Water Sol (Exper. database match) = 1E+006 mg/L (25 °C)

Exper. Ref: BEILSTEIN

Water Sol Estimate from Fragments:

Wat Sol (vl.01 est) = 1E+006 mg/L

ECOSAR Class Program (ECOSAR vl. 11):

Class(es) found:

Neutral Organics

Henrys Law Constant (25 °C) [HENRYWIN v3.20]:

Bond Method : 1.16E-008 atm-m3/mole (1.17E-003 Pa-m3/mole)

Group Method: Incomplete

For Henry LC Comparison Purposes:

User-Entered Henry LC: not entered

Henrys LC [via VP/WSol estimate using User-Entered or Estimated values]:

HLC: 1.658E-008 atm-m3/mole (1.680E-003 Pa-m3/mole)

VP: 0.136 mm Hg (source: MPBPVP)

WS: 9.95E+005 mg/L (source: User-Entered)

Page 9 of 63


-------
Log Octanol-Air Partition Coefficient (25 °C) [KOAWIN vl.10]:

Log Kow used: -0.41 (user entered)

Log Kaw used: -6.324 (HenryWin est)

Log Koa (KOAWIN vl.10 estimate): 5.914

Log Koa (experimental database): None

Probability of Rapid Biodegradation (BIOWIN v4.10):

Biowinl (Linear Model): 0.7037

Biowin2 (Non-Linear Model): 0.8455

Expert Survey Biodegradation Results:

Biowin3 (Ultimate Survey Model): 2.9955 (weeks)

Biowin4 (Primary Survey Model): 3.7148 (days-weeks)

MITI Biodegradation Probability:

Biowin5 (MITI Linear Model): 0.4388

Biowin6 (MITI Non-Linear Model): 0.4759

Anaerobic Biodegradation Probability:

Biowin7 (Anaerobic Linear Model): 0.6769

Ready Biodegradability Prediction: NO

Hydrocarbon Biodegradation (BioHCwin vl.01):

Structure incompatible with current estimation method!

Sorption to aerosols (25 Dec C)[AEROWIN vl.00]:

Vapor pressure (liquid/subcooled): 16 Pa (0.12 mm Hg)

Log Koa (Koawin est): 5.914

Kp (particle/gas partition coef. (m3/ug)):

Mackay model 1.88E-007

Octanol/air (Koa) model: 2.01E-007

Fraction sorbed to airborne particulates (phi):

Junge-Pankow model: 6.77E-006

Mackay model: 1.5E-005

Octanol/air (Koa) model: 1.61E-005

Atmospheric Oxidation (25 °C) [AopWin vl.92]:

Hydroxyl Radicals Reaction:

OVERALL OH Rate Constant = 7.1992 E-12 cm3/molecule-sec

Half-Life = 1.486 Days (12-hr day; 1.5E6 OH/cm3)

Half-Life = 17.829 Hrs

Ozone Reaction:

No Ozone Reaction Estimation

Fraction sorbed to airborne particulates (phi):

1.09E-005 (Junge-Pankow, Mackay avg)

1.61E-005 (Koa method)

Note: the sorbed fraction may be resistant to atmospheric oxidation

Soil Adsorption Coefficient (KOCWIN v2.00):

Koc: 43.89 L/kg (MCI method)

Log Koc: 1.642 (MCI method)

Koc: 0.4403 L/kg (Kow method)

Page 10 of 63


-------
Log Koc: -0.356 (Kow method)

Aqueous Base/Acid-Catalyzed Hydrolysis (25 °C) [HYDROWIN v2.00]:
Rate constants can NOT be estimated for this structure!

Bioaccumulation Estimates (BCFBAF v3.01):

Log BCF from regression-based method = 0.500 (BCF = 3.162 L/kg wet-wt)
Log Biotransformation Half-life (HL) = -1.4092 days (HL = 0.03897 days)
Log BCF Arnot-Gobas method (upper trophic) = -0.037 (BCF = 0.9183)
Log BAF Arnot-Gobas method (upper trophic) = -0.037 (BAF = 0.9183)
log Kow used: -0.41 (user entered)

Volatilization from Water:

Henry LC: 1.16E-008 atm-m3/mole (estimated by Bond SAR Method)
Half-Life from Model River: 4.846E+004 hours (2019 days)

Half-Life from Model Lake: 5.287E+005 hours (2.203E+004 days)

Removal in Wastewater Treatment:

Total removal: 1.85 percent
Total biodegradation: 0.09 percent
Total sludge adsorption: 1.76 percent
Total to Air: 0.00 percent
(using 10000 hr Bio P,A,S)

Level III Fugacity Model:

Mass Amount Half-Life Emissions

(percent)

(hr) (kg/hr)



Air

0.203 35.7

1000

Water

23.1 360

1000

Soil

76.6 720

1000

Sediment

0.0843 3.24E+003

0

Persistence Time: 679 hr

Page 11 of 63


-------
Data Evaluation Tables

Study
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for dimcthylsilancdiol. CAS Registry
Number: 1066-42-8; HERO ID: 7995011

Domain

Metric

Qualitative
Determination

(/.t'., High,
Medium, Low,
Unacceptable, or
Not Rated |NRJ)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1

Appropriateness

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Test

Reliability

Reliability / Unbiased
(Method Objectivity)

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Reliability / Analytical
Method

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Other

Databases

High

The information or data
is from a recognized data
collection/repositor y
where data are peer-
reviewed by experts in
the field, are broadly
available to the public
for review and use OR
includes references to
the original sources.

1

1

1

Models

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR







Sum of scores:

2

2

2

Mid.

Medium

Low

Overall Score = Sum of
Weighted Scores/Sum
of Metric Weighting
Factors:

1

Overall
Score

(Rounded):

1

1 and 1

l .'and :

2 'and '





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Physical State reported by this reference.
Cited reference: Hyde; Journal of the American Chemical Society; vol. 75; (1953); p. 2166

Page 12 of 63


-------
Study
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for dimcthylsilancdiol. CAS Registry
Number: 1066-42-8; HERO ID: 7995011

Domain

Metric

Qualitative
Determination

(i.e., High,
Medium, Low,
Unacceptable, or
Not Rated NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1

Appropriateness

High

Measured data are
consistent with the subject
chemical substance
structural features (e.g.,
presence of certain
functional groups) or other
physical/chemical
properties or behaviors.

1

1

1

Test

Reliability

Reliability / Unbiased
(Method Objectivity)

Medium

There is no indication that
the methodology for
producing the information
was biased towards a
particular product or
outcome.

2

1

2

Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to
be appropriate based on
the data's inclusion in a
peer-reviewed/ recognized
database or other
secondary source.

2

1

2

Other

Databases

High

The information or data is
from a recognized data
collection/repositor y
where data are peer-
reviewed by experts in the
field, are broadly available
to the public for review
and use OR includes
references to the original
sources.

1

1

1



Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR







Sum of scores:

7

5

7

Mid.

Medium

l.nu

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting
Factors:

1.4

Overall
Score

(Rounded):

1.4

1 and 1

1 "and 2 '

2 'and '





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Melting Point reported by this reference.

Cited references: Makarova et al. 2006; Kennan et al. 1999; Cella and Carpenter 1994; Harris 1963; Chrzczonowicz et al.
1960; Takiguchi 1959; Kantor 1953; Hyde 1953; Kantor 1953; Hyde 1953

Page 13 of 63


-------
Studv

Elsevier (2021). Rcaxvs: phvsical-chcmical property data for dimcthylsilancdiol. CAS Registry Number:

Reference:

1066-42-8; HERO ID:

7995011













Qualitative













Determination (i.e.,





Metric
Weighting
Factor



Domain

Metric

High, Medium,

Low,

Comments

Metric
Score

Weighted

Score





Unacceptable, or
Not Rated NR|)









Representativeness

High

Data are measured or
estimated for the

1

1

1

Substance





subject chemical
substance.









Appropriateness

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR



Reliability /

Medium

There is no indication

2

1

2



Unbiased (Method
Objectivity)



that the methodology
for producing the
information was
biased towards a
particular product or







Test

Reliability





outcome.







Reliability /
Analytical Method

Medium

The analytical method
is unknown but is
likely to be appropriate
based on the data's
inclusion in a peer-
reviewed/recognize d
database or other
secondary source.

2

1

2



Databases

High

The information or
data is from a
recognized data
collection/repositor y
where data are peer-

1

1

1

Other





reviewed by experts in
the field, are broadly
available to the public
for review and use OR
includes references to
the original sources.









Models

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR







Sum of scores:

6

4

6

Midi

Medium

l.ou

Overall Score = Sum
of Weighted
Scores/Sum of Metric
Weighting Factors:

1.5

Overall
Score

(Rounded):

1.5

1 ;n id 1 "

1 "and : ^

: ^ and ^





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Density reported by this reference.
Cited reference: Hyde; Journal of the American Chemical Society; vol. 75; (1953); p. 2166

Page 14 of 63


-------
Study
Reference:

Rsc (2021). ChcmSpidcr: Dimcthylsilancdiol. HERO ID: 7999339





Qualitative













Determination





Metric
Weighting
Factor



Domain

Metric

(i.e., High,
Medium, Low,

Comments

Metric
Score

Weighted

Score





Unacceptable, or
Not Rated |NR|)







Substance

Representativeness

High

Data are measured or
estimated for the
subject chemical
substance.

1

1

1



Appropriateness

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR



Reliability / Unbiased

Medium

There is no indication

2

1

2



(Method Objectivity)



that the methodology
for producing the
information was
biased towards a
particular product or
outcome.







Test

Reliability

Reliability /
Analytical Method

Medium

The analytical method
is unknown but is
likely to be
appropriate based on
the data's inclusion in
a peer-

reviewed/recognize d
database or other
secondary source.

2

1

2



Databases

Medium

Data is from a
publicly available
secondary source with
references to non-peer

2

1

2

Other





reviewed original
sources.









Models

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Sum of scores:

7

4

7

Midi

Medium

I.HM

()\ erall Score = Sum
of Weighted
Scores/Sum of
Mdric Weighting
Factors:

1.75

Overall
Score

(Rounded):

1.8

1 and 1."

1 "and 2 ^

2 'and '





Overall
Quality
Level:

Medium

The reviewer agreed with the overall rating for the Density reported by this reference.
Cited reference: Alfa Aesar

Page 15 of 63


-------
Study

Elsevier (2021). Rcaxvs: phvsical-chemical property data for dimcthylsilancdiol. CAS Registry

Reference:

Number: 1066-42-8. HERO ID: 7995011













Qualitative









Domain

Metric

Determination (i.e.,

High, Medium,
Low, Unacceptable,
or Not Rated |NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score



Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1



Appropriateness

High

Measured data are
consistent with the

1

1

1

Substance





subject chemical
substance structural
features (e.g., presence of
certain functional
groups) or other
physical/chemical
properties or behaviors.









Reliability /

Medium

There is no indication

2

1

2



Unbiased (Method
Objectivity)



that the methodology for
producing the
information was biased







Test

Reliability





towards a particular
product or outcome.







Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to
be appropriate based on
the data's inclusion in a
peer- reviewed/recognize
d database or other
secondary source.

2

1

2

Other

Databases

High

The information or data
is from a recognized data
collection/repository
where data are peer-
reviewed by experts in
the field, are broadly
available to the public for
review and use OR
includes references to the
original sources.

1

1

1



Models

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Sum of scores:

7

5

7

Mid.

Medium

l.ow

Overall Score = Sum of
Weighted Scores/Sum
of Metric Weighting
Factors:

1.4

Overall
Score

(Rounded):

1.4

1 and 1

1 "and : ^

2 'and '





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Water Solubility reported by this reference.
Cited reference: Hyde; Journal of the American Chemical Society; vol. 75; (1953); p. 2166

Page 16 of 63


-------
Studv

U.S.EPA (2021). Chemistry dashboard information for Dimcthylsilancdiol. CAS registry number:

Reference:

1066-42-8. HERO ID: 7996867













Qualitative









Domain

Metric

Determination (/.e.,

High, Medium,
Low, Unacceptable,
or Not Rated |NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score



Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1



Appropriateness

High

Measured data are
consistent with the

1

1

1

Substance





subject chemical
substance structural
features (e.g., presence of
certain functional
groups) or other
physical/chemical
properties or behaviors.









Reliability /

Medium

There is no indication

2

1

2



Unbiased (Method
Objectivity)



that the methodology for
producing the
information was biased







Test

Reliability





towards a particular
product or outcome.







Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to
be appropriate based on
the data's inclusion in a
peer-reviewed/recognize
d database or other
secondary source.

2

1

2

Other

Databases

High

The information or data
is from a recognized data
collection/repository
where data are peer-
reviewed by experts in
the field, are broadly
available to the public for
review and use OR
includes references to the
original sources.

1

1

1



Models

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Sum of scores:

7

5

7

Mid.

Medium

Low

Overall Score = Sum of

1.4

Overall
Score

(Rounded):

1.4







Weighted Scores/Sum
of Metric Weighting
Factors:





1 and 1

1 "and : ^

2 'and '





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Water Solubility reported by this reference.
Cited reference: Kovdienko et. al. Molecular informatics 29.5 (2010): 394-406.

Page 17 of 63


-------
Study
Reference:

U.S. EPA. (2021). Chemistry dashboard information for Dimcthylsilancdiol. CAS registry number:
1066-42-8; HERO ID: 7996867

Domain

Metric

Qualitative
Determination

\i.e., Hi«h,
Medium, Low,
Unacceptable, or
Not rated]

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1

Appropriateness

High

Measured data are
consistent with the subject
chemical substance
structural features (e.g.,
presence of certain
functional groups) or other
physical/chemical
properties or behaviors.

1

1

1

Test

Reliability

Reliability /
Unbiased (Method
Objectivity)

Medium

There is no indication that
the methodology for
producing the information
was biased towards a
particular product or
outcome.

2

1

2

Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to
be appropriate based on
the data's inclusion in a
peer-reviewed/ recognized
database or other
secondary source.

2

1

2

Other

Databases

High

The information or data is
from a recognized data
collection/repository
where data are peer-
reviewed by experts in the
field, are broadly available
to the public for review
and use OR includes
references to the original
sources.

1

1

1



Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Sum of scores:

7

5

7

Mid.

Medium

Low

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting
Factors:

1.4

Overall
Score

(Rounded):

1.4

1 ;iih.I 1

1 "and : ^

2 'and '





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Water Solubility reported by this reference.
Cited reference: Physprop

Page 18 of 63


-------
Study
Reference:

U.S. EPA (2021). Pubchcm: Dimcthylsilancdiol. CAS registry number: 1066-42-8. HERO ID: 7998093





Qualitative













Determination





Metric
Weighting
Factor



Domain

Metric

(i.e., High,
Medium, Low,

Comments

Metric
Score

Weighted

Score





Unacceptable, or
Not Rated |NR|)









Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1

Substance

Appropriateness

High

Measured data are consistent
with the subject chemical
substance structural features
(e.g., presence of certain
functional groups) or other
physical/chemical properties
or behaviors.

1

1

1



Reliability /

Medium

There is no indication that the

2

1

2



Unbiased (Method
Objectivity)



methodology for producing
the information was biased
towards a particular product
or outcome.







Test

Reliability

Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to be
appropriate based on the
data's inclusion in a peer-
reviewed/recognize d
database or other secondary
source.

2

1

2



Databases

Medium

Data is from a publicly
available secondary source
with references to non-peer

2

1

2

Other





reviewed original sources.









Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Sum of scores:

8

5

8

Midi

Medium

1 A»\X

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting Factors:

1.6

Overall
Score

(Rounded):

1.6

1 and

1 "and : ^

: ^ and ^





Overall

High

1."









Quality
Level:



The reviewer agreed with the overall rating for the Water Solubility reported by this reference.
Cited reference: EPA DSSTox

Page 19 of 63


-------
Study
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for dimcthylsilancdiol. CAS Registry
Number: 1066-42-8. HERO ID: 7995011

Domain

Metric

Qualitative
Determination

(/.t'., Hi«h,
Medium, Low,
Unacceptable, or
Not Rated |NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or estimated
for the subject chemical
substance.

1

1

1

Appropriateness

High

Measured data are consistent
with the subject chemical
substance structural features
(e.g., presence of certain
functional groups) or other
physical/chemical properties or
behaviors.

1

1

1

Test

Reliability

Reliability /
Unbiased (Method
Objectivity)

Medium

There is no indication that the
methodology for producing the
information was biased
towards a particular product or
outcome.

2

1

2

Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to be
appropriate based on the data's
inclusion in a peer- reviewed/
recognized database or other
secondary source.

2

1

2

Other

Databases

High

The information or data is from
a recognized data
collection/repository where
data are peer-reviewed by
experts in the field, are broadly
available to the public for
review and use OR includes
references to the original
sources.

1

1

1

Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Sum of scores:

7

5

7

1 huh

Medium

1 A»\X

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting Factors:

1.4

Overall
Score
(Rounded):

1.4

1 and
1 "

1 ~ and

: ^ and ^





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Octanol Water Coefficient (logKow) reported by this reference.
Cited references: Xu, Shihe; Kropscott, Bruce; Analytical Chemistry; vol. 84; nb. 4; (2012); p. 1948-1955

Page 20 of 63


-------
Study
Reference:

Xu, S. and B. Kropscott (2012). Method for simultaneous determination of partition coefficients for

cyclic volatile mcthylsiloxancs and dimcthylsilancdiol. Analytical Chemistry 84(4): 1948-1955.
HERO ID: 2188633







Qualitative













Determination





Metric
Weighting
Factor



Domain

Metric

(/.t'., Hi«h,
Medium, Low,

Comments

Metric
Score

Weighted

Score





Unacceptable, or
Not Rated [NR])









Representativeness

High

Data are measured or
estimated for the
subject chemical
substance.

1

1

1

Substance

Appropriateness

High

Measured data are
consistent with the
subject chemical
substance structural
features or other
physical/chemical
properties or
behaviors.

1

1

1



Reliability / Unbiased
(Method Objectivity)

High

The methodology for
producing the
information is
designed to answer a
specific question, and
the methodology's
objective is clear.

1

1

1

Test

Reliability

Reliability / Analytical
Method

High

Data are obtained by
accepted standard
analytical methods,
including, but not
limited to OECD
guidelines for
physical-chemical
properties or another
developed standard.

1

1

1



Databases

NR

Rating of this factor is

NR

NR

NR

Other





not applicable to this
kind of information.







Models

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Sum of scores:

4

4

4

Midi

Medium

1 A»\X

()\ erall Score = Sum
of Weighted
Scores/Sum of Metric
Weighting Factors:

1

Overall
Score

(Rounded):

1

1 and 1

1 "and : ^

2 ' and '





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Octanol Water Coefficient (logKow) reported by this reference.

Page 21 of 63


-------
Studv

Elsevier (2021). Rcaxvs: physical-chemical property data for dimcthylsilancdiol. CAS Registry Number:

Reference:

1066-42-8. HERO ID: 7995011













Qualitative













Determination





Metric
Weighting
Factor



Domain

Metric

(i.e., High,
Medium, Low,

Comments

Metric
Score

Weighted Score





Unacceptable, or
Not Rated |NR|)









Representativeness

High

Data are measured or
estimated for the

1

1

1

Substance





subject chemical
substance.









Appropriateness

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR



Reliability /

Medium

There is no indication

2

1

2



Unbiased (Method
Objectivity)



that the methodology
for producing the
information was
biased towards a
particular product or
outcome.







Test

Reliability

Reliability /
Analytical Method

Medium

The analytical method
is unknown but is
likely to be
appropriate based on
the data's inclusion in
a peer-reviewed/
recognized database or
other secondary
source.

2

1

2



Databases

High

The information or
data is from a
recognized data
collection/repository
where data are peer-

1

1

1

Other





reviewed by experts in
the field, are broadly
available to the public
for review and use OR
includes references to
the original sources.









Models

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Sum of scores:

6

4

6

1 huh

Medium

l.ou

Overall Score = Sum

of Weighted
Scores/Sum of Metric
Weighting Factors:

1.5

Overall
Score

(Rounded):

1.5

1 III id 1 "

1 "and : ^

: ^ and ^





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Refractive Index reported by this reference.
Cited reference: Hyde; Journal of the American Chemical Society; vol. 75; (1953); p. 2166

Page 22 of 63


-------
Study

U.S. EPA (U.S. Environmental Protection Aucncv). (2012). Estimation Programs Interface Suite

™ for

Reference:

Microsoft^; Windows, v 4.11 IComnutcr Program 1. Washington. DC. HERO ID:2347246







Qualitative













Determination (/.e.,



Metric
Score

Metric

Weighted

Score

Domain

Metric

High, Medium. Low,
Unacceptable, or Not
Rated |NR|)

Comments

Weighting
Factor

Substance

Representativeness

NR

The metric is not applicable to
this study type (SAR).

NR

1

NR

Appropriateness

NR

The metric is not applicable to
this study type (SAR).

NR

1

NR

Test

Reliability

Reliability /
Unbiased (Method
Objectivity)

NR

The metric is not applicable to
this study type (SAR).

NR

1

NR

Reliability /
Analytical Method

NR

The metric is not applicable to
this study type (SAR).

NR

1

NR



Databases

NR

The metric is not applicable to
this study type (SAR).

NR

1

NR



Models

High

The models in EPI Suite™
have defined endpoints.
Chemical domain and
performance statistics for each
model are known, and
unambiguous algorithms are
available in the EPI Suite™
documentation and/or cited
references to establish their
scientific validity. Many EPI
Suite™ models have

1

1

1

Other





correlation coefficients >0.7,











cross-validated correlation
coefficients >0.5, and
standard error values <0.3;
however, correlation
coefficients (r2, q2) for the
regressions of some
environmental fate models
(i.e., BIOWIN) are lower, as
expected, compared to
regressions which have
specific experimental values
such as water solubility or log
Kow (octanol-water partition
coefficient).







Sum of scores:

1

1

1

1 huh

Medium

1 A»\X

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting Factors:

1

Overall
Score

(Rounded):

1

1 and 1

1 "and : '

: ^ ;md ^





Overall
Quality
Level:

High

Page 23 of 63


-------
Tetramethyldisiloxanediol (CASRN 1118-15-6) Data Extraction Tables

Table 1. Physical State Study Summary

Study Type

Result

Comments

Affiliated Reference

Data Quality Evaluation Results

Experimental

3 values reported in Reaxys: 2
values were monoclinic crystal
system (solid), 1 value was
needle crystal shape (solid)



(Elsevier. 202Id)

High



Study Type

Result

Comments

Affiliated Reference

Data Quality Evaluation Results

Experimental

1 property reported in
Reaxys: color - white



(Elsevier. 202ldi

High

Table 3. Melting Point Study Summary

Study Type

Substance
Purity

Result

Comments

Affiliated Reference

Data Quality
Evaluation Results

Experimental

NR

62-68°C

19 values were reported in Reaxys; 8 values were in the
range of 62-68 °C; one value was outside of this range; 9
values were reported with the test substance in a solvent.

(Elsevier. 202 Id)

High

Experimental

NR

66 °C

NR

(Havnes. 2014)

High

Table 4. Boiling Point Study Summary
No Boiling Point data were identified for this chemical.

Page 24 of 63


-------
Table 5. Density Study Summary

Study Type

Study
Details

Reference
Substance

Temperature

Result

Comments

Affiliated
Reference

Data Quality
Evaluation
Results

Experimental







1.08-1.15 g/cm3

4 values reported in Reaxys; 2 values were
1.118 g/cm3 at 16 °C; 2 values did not have
measurement temperatures. Crystallographic
density.

(Elsevier. 202Id)

High

Experimental







1.095 g/cm3

density at 25 °C

(Havnes. 2014)

High

Table 6. Vapor Pressure Study Summary

No Vapor Pressure data were identified for this chemical.

Table 7. Vapor Density Study Summary

No Vapor Density data were identified for this chemical.

Table 8. Water Solubility Study Summary

Study Type

Substance
Purity

Temperature

pH

Analytical
Method

Result

Comments

Affiliated
Reference

Data Quality
Evaluation Results

Experimental

NR

20-25 °C

NR



110-115 g/L

3 values reported in Reaxys,
reported as 100 g solvent
(water) dissolves 11-11.5 g
substance

(Elsevier.
202 Id)

High



Experimental

NR

NR

NR



0.662 M

Equivalent to 110,000 mg/L
based on MW
166.32 g/mol

(U.S. EPA.
2021a)

High



Experimental

NR

NR

NR



0.661 M

Equivalent to 110,000 mg/L
based on MW

166.32 g/mol

(U.S. EPA.
2021a)

High



Experimental

NR

NR

NR



0.66 M

Equivalent to 100,000 mg/L
based on MW
166.32 g/mol

(NLM. 2021a)

High

Page 25 of 63


-------
Table 9. Octanol Water Coefficient (logKow) Study Summary
No Octanol Water Coefficient (logKow) data were identified for this chemical.

Table	ry's Law Constant Study Summary

No Henrys Law data were identified for this chemical.

Table 11. Flash Point Study Summary

No Flash Point data were identified for this chemical.

Table 12. Auto Flammability Study Summary
No Autoflammability data were identified for this chemical.

Table 13. Viscosity Study Summary
No Viscosity data were identified for this chemical.

Table 14. Refractive Index Study Summary

Study Type

Apparatus

Result

Comments

Affiliated
Reference

Data Quality
Evaluation
Results

Experimental

25 °C

1.457-1.466

2 values reported in Reaxvs: 1.457-1.461 (nl) and 1.462-1.466 (ml),
589.3 nni

(Elsevier. 202Id)

High

Table 15. Dielectric Constant Study Summary
No Dielectric Constant data were identified for this chemical.

Page 26 of 63


-------
EPI Suite1M Model Outputs
(U.S. EPA. 2012)

SMILES: [Si](0)(0[Si](0)(C)C)(C)C
CHEM: 1,3-Disiloxanediol, 1,1,3,3-tetramethyl-
MOL FOR: C4 H14 03 Si2
MOLWT: 166.33

	EPI SUMMARY (v4.11)	

Physical Property Inputs:

Log Kow (octanol-water):	

Boiling Point (°C):	

Melting Point (°C): 66.00

Vapor Pressure (mm Hg):	

Water Solubility (mg/L): 1.1E+005
Henry LC (atm-m3/mole):	

Log Octanol-Water Partition Coef (SRC):

Log Kow (KOWWIN vl.68 estimate) = 1.74

Boiling Pt, Melting Pt, Vapor Pressure Estimations (MPBPVP vl.43):

Boiling Pt (°C): 236.15 (Adapted Stein & Brown method)

Melting Pt (°C): 13.78 (Mean or Weighted MP)

VP(mm Hg, 25 °C): 0.00196 (Modified Grain method)

VP (Pa, 25 °C): 0.261 (Modified Grain method)

Subcooled liquid VP: 0.00474 mm Hg (25 °C, Mod-Grain method): 0.632 Pa (25 °C, Mod-Grain
method)

Water Solubility Estimate from Log Kow (WSKOW vl.42):

Water Solubility at 25 °C (mg/L): 914.6
log Kow used: 1.74 (estimated)
melt pt used: 66.00 °C

Water Sol (Exper. database match) = 1.1E+005 mg/L (25 °C)

Exper. Ref: BEILSTEIN

Water Sol Estimate from Fragments:

Wat Sol (vl.01 est) = 1.5402E+005 mg/L

ECOSAR Class Program (ECOSAR vl. 11):

Class(es) found:

Neutral Organics

Henrys Law Constant (25 °C) [HENRYWIN v3.20]:

Bond Method: 1.59E-008 atm-m3/mole (1.61E-003 Pa-m3/mole)

Group Method: Incomplete

For Henry LC Comparison Purposes:

User-Entered Henry LC: not entered

Henrys LC [via VP/WSol estimate using User-Entered or Estimated values]:

HLC: 3.900E-009 atm-m3/mole (3.951E-004 Pa-m3/mole)

VP: 0.00196 mm Hg (source: MPBPVP)

Page 27 of 63


-------
WS: 1.1E+005 mg/L (source: User-Entered)

Log Octanol-Air Partition Coefficient (25 °C) [KOAWIN vl.10]:

Log Kow used: 1.74 (KowWin est)

Log Kaw used: -6.187 (HenryWin est)

Log Koa (KOAWIN vl.10 estimate): 7.927

Log Koa (experimental database): None

Probability of Rapid Biodegradation (BIOWIN v4.10):

Biowinl (Linear Model): 0.6684

Biowin2 (Non-Linear Model): 0.6563

Expert Survey Biodegradation Results:

Biowin3 (Ultimate Survey Model): 2.8316 (weeks)

Biowin4 (Primary Survey Model): 3.6078 (days-weeks)

MITI Biodegradation Probability:

Biowin5 (MITI Linear Model): 0.2190

Biowin6 (MITI Non-Linear Model): 0.0999

Anaerobic Biodegradation Probability:

Biowin7 (Anaerobic Linear Model): 0.5178

Ready Biodegradability Prediction: NO

Hydrocarbon Biodegradation (BioHCwin vl.01):

Structure incompatible with current estimation method!

Sorption to aerosols (25 Dec C)[AEROWIN vl.00]:

Vapor pressure (liquid/subcooled): 0.632 Pa (0.00474 mm Hg)

Log Koa (Koawin est): 7.927

Kp (particle/gas partition coef. (m3/ug)):

Mackay model: 4.75E-006

Octanol/air (Koa) model: 2.07E-005

Fraction sorbed to airborne particulates (phi):

Junge-Pankow model: 0.000171

Mackay model: 0.00038

Octanol/air (Koa) model: 0.00166

Atmospheric Oxidation (25 °C) [AopWin vl.92]:

Hydroxyl Radicals Reaction:

OVERALL OH Rate Constant = 7.4984 E-12 cm3/molecule-sec

Half-Life = 1.426 Days (12-hr day; 1.5E6 OH/cm3)

Half-Life = 17.117Hrs

Ozone Reaction:

No Ozone Reaction Estimation

Fraction sorbed to airborne particulates (phi):

0.000276 (Junge-Pankow, Mackay avg)

0.00166 (Koa method)

Note: the sorbed fraction may be resistant to atmospheric oxidation

Soil Adsorption Coefficient (KOCWIN v2.00):

Koc: 340.7 L/kg (MCI method)

Page 28 of 63


-------
Log Koc: 2.532 (MCI method)

Koc: 32.34 L/kg (Kow method)

Log Koc: 1.510 (Kow method)

Aqueous Base/Acid-Catalyzed Hydrolysis (25 °C) [HYDROWIN v2.00]:
Rate constants can NOT be estimated for this structure!

Bioaccumulation Estimates (BCFBAF v3.01):

Log BCF from regression-based method = 0.817 (BCF = 6.562 L/kg wet-wt)
Log Biotransformation Half-life (HL) = -0.4475 days (HL = 0.3569 days)
Log BCF Arnot-Gobas method (upper trophic) = 0.795 (BCF = 6.23)
Log BAF Arnot-Gobas method (upper trophic) = 0.795 (BAF = 6.23)
log Kow used: 1.74 (estimated)

Volatilization from Water:

Henry LC: 1.59E-008 atm-m3/mole (estimated by Bond SAR Method)
Half-Life from Model River: 4.749E+004 hours (1979 days)

Half-Life from Model Lake: 5.182E+005 hours (2.159E+004 days)

Removal in Wastewater Treatment:

Total removal 2.07 percent
Total biodegradation: 0.09 percent
Total sludge adsorption: 1.97 percent
Total to Air: 0.00 percent
(using 10000 hr Bio P,A,S)

Level III Fugacity Model:

Mass Amount Half-Life Emissions

(percent)

(hr)

(kg/hr)



Air

0.246

34.2

1000

Water

17.9

360

1000

Soil

81.6

720

1000

Sediment

0.258

3.24E+003

0

Persistence Time: 722 hr

Page 29 of 63


-------
Data Evaluation Tables

Study
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for tctramcthyl-l,3-disiloxanediol. CAS
Registry Number: 1118-15-6. HERO ID: 7994661

Domain

Metric

Qualitative
Determination

(/.t'., High,
Medium, Low,
Unacceptable, or
Not Rated NRJ)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or estimated
for the subject chemical
substance.

1

1

1

Appropriateness

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Test

Reliability

Reliability /
Unbiased (Method
Objectivity)

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Reliability /
Analytical Method

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Other

Databases

High

The information or data is from
a recognized data
collection/repository where
data are peer-reviewed by
experts in the field, are broadly
available to the public for
review and use OR includes
references to the original
sources.

1

1

1

Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Sum of scores:

2

2

2

II lull

Medium

1 A»\X

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting Factors:

1

Overall
Score

(Rounded):

1

1 and
1 "

1and

2 ^ and ^





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Physical State reported by this reference.
Cited references: Hyde 1953; Kakudo et al. 1953; Kakudo et al 1953.

Page 30 of 63


-------
Study
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for tctramcthyl-l,3-disiloxancdiol. CAS
Rcgistrv Number: 1118-15-6. HERO ID: 7994661

Domain

Metric

Qualitative
Determination

(/.t'., High,
Medium, Low,
Unacceptable, or
Not Rated |NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or
estimated for the
subject chemical
substance.

1

1

1

Appropriateness

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Test

Reliability

Reliability / Unbiased
(Method Objectivity)

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Reliability / Analytical
Method

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Other

Databases

High

The information or data
is from a recognized
data

collection/repositor y
where data are peer-
reviewed by experts in
the field, are broadly
available to the public
for review and use OR
includes references to
the original sources.

1

1

1

Models

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Sum of scores:

2

2

2

Midi

Medium

1 .o\\

()\ erall Score = Sum
of Weighted
Scores/Sum of Metric
Weighting Factors:

1

Overall Score
(Rounded):

1

1 and 1 "

1 "and 2 ^

2 ^ and ^





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Physical Properties reported by this reference.

Cited reference: Lucas; Martin; Journal of the American Chemical Society; vol. 74; (1952); p. 5225, View inReaxys

Page 31 of 63


-------
Study
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for tctramcthyl-l,3-disiloxancdiol. CAS
Rcgistrv Number: 1118-15-6. HERO ID: 7994661

Domain

Metric

Qualitative
Determination

(/.t'., High,
Medium, Low,
Unacceptable, or
Not Rated |NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1

Appropriateness

High

Measured data are consistent
with the subject chemical
substance structural features
(e.g., presence of certain
functional groups) or other
physical/chemical properties
or behaviors.

1

1

1

Test

Reliability

Reliability /
Unbiased (Method
Objectivity)

Medium

There is no indication that
the methodology for
producing the information
was biased towards a
particular product or
outcome.

2

1

2

Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to be
appropriate based on the
data's inclusion in a peer-
reviewed/recognized
database or other secondary
source.

2

1

2

Other

Databases

High

The information or data is
from a recognized data
collection/repository where
data are peer-reviewed by
experts in the field, are
broadly available to the
public for review and use
OR includes references to
the original sources.

1

1

1



Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Sum of scores:

7

5

7

Midi

Medium

l.im

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting Factors:

1.4

Overall
Score

(Rounded):

1.4

1 ;n id 1 "

1 "and : ^

2.' and ^





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Melting Point reported by this reference.

Cited references: Makarova et al. 2006; Lucas 1952; Cella et al. 1994; Cypryk et al. 1993; Lickiss et al. 1993; Zachernyuk
et al. 1985; Lebedev et al. 1979; Martyakova et al. 1976; Baratova et al. 1975; Andrianov 1974; Ungurenasu 1961; Borisow
etal. 1966; Barnes 1966.

Page 32 of 63


-------
Studv

Havncs, W. M. (2014). CRC Handbook of Chemistry and Physics l,l,3,3-Tetramcthyl-l,3-



Reference:

disiloxancdiol. Boca Raton, FL, CRC Press. Tavlor & Francis Group. HERO ID: 7998725







Qualitative













Determination





Metric
Weighting
Factor



Domain

Metric

{le„ Hi«h,
Medium, Low,

Comments

Metric
Score

Weighted

Score





Unacceptable, or
Not Rated |NR|)









Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1



Appropriateness

High

Measured data are
consistent with the

1

1

1

Substance





subject chemical
substance structural
features (e.g., presence of
certain functional
groups) or other physical/
chemical properties or
behaviors.









Reliability /

Medium

There is no indication

2

1

2



Unbiased (Method
Objectivity)



that the methodology for
producing the
information was biased







Test

Reliability





towards a particular
product or outcome.







Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to
be appropriate based on
the data's inclusion in a
peer-reviewed/
recognized database or
other secondary source.

2

1

2



Databases

High

The information or data
is from a recognized data
collection/repository
where data are peer-

1

1

1

Other





reviewed by experts in
the field, are broadly
available to the public for
review and use OR
includes references to the
original sources.









Models

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Sum of scores:

7

5

7

Mid.

Medium

l.nu

Overall Score = Sum of
Weighted Scores/Sum
of Metric Weighting
Factors:

1.4

Overall
Score

(Rounded):

1.4

1 and 1

1 "and : ^

2 'and '





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Melting Point reported by this reference.

Page 33 of 63


-------
Studv

Elsevier (2021). Rcaxvs: phvsical-chemical property data for tctramcthyl-l,3-disiloxancdiol. CAS

Reference:

Registry Number: 1118-15-6. HERO ID: 7994661











Qualitative









Domain

Metric

Determination (i.e.,

High, Medium,
Low, Unacceptable,
or Not Rated |NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score



Representativeness

High

Data are measured or
estimated for the

1

1

1

Substance





subject chemical
substance.









Appropriateness

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR



Reliability /

Medium

There is no indication

2

1

2



Unbiased (Method
Objectivity)



that the methodology
for producing the
information was biased
towards a particular







Test

Reliability





product or outcome.







Reliability /
Analytical Method

Medium

The analytical method
is unknown but is likely
to be appropriate based
on the data's inclusion
in a peer-reviewed/
recognized database or
other secondary source.

2

1

2



Databases

High

The information or data
is from a recognized
data collection/

1

1

1

Other





repository where data
are peer-reviewed by
experts in the field, are
broadly available to the
public for review and
use OR includes
references to the
original sources.









Models

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Sum of scores:

6

4

6

Midi

Medium

1 A»\X

()\ erall Score = Sum
of Weighted
Scores/Sum of Metric
\\ eighting Factors:

1.5

Overall
Score

(Rounded):

1.5

1 and 1 "

1 "and 2 ^

:.^aiid ^





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Density reported by this reference.
Cited references: Lickiss et al. 1993; Hyde 1953; Kakudo et al. 1953; Kakudo et al 1953.

Page 34 of 63


-------
Studv

Haynes, W. M. (2014). CRC Handbook of Chemistry and Physics l,l,3,3-Tetramcthyl-l,3-



Reference:

disiloxancdiol. Boca Raton, FL, CRC Press. Tavlor & Francis Group. HERO ID: 7998725







Qualitative













Determination





Metric
Weighting
Factor



Domain

Metric

(i.e., High,
Medium, Low,

Comments

Metric
Score

Weighted

Score





Unacceptable, or
Not Rated |NR|)









Representativeness

High

Data are measured or
estimated for the

1

1

1

Substance





subject chemical
substance.









Appropriateness

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR



Reliability / Unbiased

Medium

There is no indication

2

1

2



(Method Objectivity)



that the methodology
for producing the
information was biased
towards a particular







Test
Reliability





product or outcome.







Reliability / Analytical
Method

Medium

The analytical method
is unknown but is likely
to be appropriate based
on the data's inclusion
in a peer-reviewed/
recognized database or
other secondary source.

2

1

2



Databases

High

The information or data
is from a recognized
data collection/

1

1

1

Other





repository where data
are peer-reviewed by
experts in the field, are
broadly available to the
public for review and
use OR includes
references to the
original sources.









Models

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Sum of scores:

6

4

6

Midi

Medium

I.HM

()\ erall Score = Sum
of Weighted
Scores/Sum of Metric
\\ eighting Factors:

1.5

Overall
Score

(Rounded):

1.5

1 ;iihJ 1

1 "and 2 ^

2.'Mild '





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Density reported by this reference.

Page 35 of 63


-------
Studv

Elsevier (2021). Rcaxvs: phvsical-chemical property data for tctramcthyl-l,3-disiloxancdiol. CAS

Reference:

Rcgistrv Number: 1118-15-6. HERO ID: 7994661











Qualitative









Domain

Metric

Determination (i.e.,
High, Medium, Low,
Unacceptable, or
Not Rated |NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score



Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1



Appropriateness

High

Measured data are
consistent with the

1

1

1

Substance





subject chemical
substance structural
features (e.g., presence of
certain functional
groups) or other physical/
chemical properties or
behaviors.









Reliability /

Medium

There is no indication

2

1

2



Unbiased (Method
Objectivity)



that the methodology for
producing the
information was biased







Test

Reliability





towards a particular
product or outcome.







Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to
be appropriate based on
the data's inclusion in a
peer-reviewed/recognize
d database or other
secondary source.

2

1

2



Databases

High

The information or data
is from a recognized data
collection/repositor y
where data are peer-

1

1

1

Other





reviewed by experts in
the field, are broadly
available to the public for
review and use OR
includes references to the
original sources.









Models

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Sum of scores:

7

5

7

Mid.

Medium

l.nu

Overall Score = Sum of
Weighted Scores/Sum
of Metric Weighting
Factors:

1.4

Overall
Score

(Rounded):

1.4

1 and 1

1 "and : ^

2 ' and '





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Water Solubility reported by this reference.
Cited references: Sokolow 1959; Hyde 1953; Hyde 1953

Page 36 of 63


-------
Studv

U.S. EPA (2021). Chemistry dashboard information for 1,3-Disiloxancdiol, 1,1,3,3- tctramcthyl-. CAS

Reference:

rcgistrv number: 1118-15-6. HERO ID: 7995923











Qualitative









Domain

Metric

Determination (i.e.,

High, Medium,
Low, Unacceptable,
or Not Rated |NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score



Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1



Appropriateness

High

Measured data are
consistent with the

1

1

1

Substance





subject chemical
substance structural
features (e.g., presence of
certain functional
groups) or other physical/
chemical properties or
behaviors.









Reliability /

Medium

There is no indication

2

1

2



Unbiased (Method
Objectivity)



that the methodology for
producing the
information was biased







Test

Reliability





towards a particular
product or outcome.







Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to
be appropriate based on
the data's inclusion in a
peer-reviewed/
recognized database or
other secondary source.

2

1

2



Databases

High

The information or data
is from a recognized data
collection/repository
where data are peer-

1

1

1

Other





reviewed by experts in
the field, are broadly
available to the public for
review and use OR
includes references to the
original sources.









Models

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Sum of scores:

7

5

7

Mid.

Medium

l.nu

Overall Score = Sum of
Weighted Scores/Sum
of Metric Weighting
Factors:

1.4

Overall
Score

(Rounded):

1.4

1 and 1

1 "and : ^

2 ' and '





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Water Solubility reported by this reference.
Cited reference: Kovdienko, et. al. Molecular informatics 29.5 (2010): 394-406.

Page 37 of 63


-------
Studv

U.S. EPA (2021). Chemistry dashboard information for 1,3-Disiloxancdiol, 1,1,3,3- tetramcthyl-. CAS

Reference:

rcgistrv number: 1118-15-6. HERO ID: 7995923











Qualitative













Determination





Metric
Weighting
Factor



Domain

Metric

(/.t'., High,
Medium, Low,

Comments

Metric
Score

Weighted

Score





Unacceptable, or
Not Rated NR|)









Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1



Appropriateness

High

Measured data are
consistent with the subject

1

1

1

Substance





chemical substance
structural features (e.g.,
presence of certain
functional groups) or other
physical/chemical
properties or behaviors.









Reliability /

Medium

There is no indication that

2

1

2



Unbiased (Method
Objectivity)



the methodology for
producing the information
was biased towards a







Test

Reliability





particular product or
outcome.







Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to be
appropriate based on the
data's inclusion in a peer-
reviewed/recognized
database or other secondary
source.

2

1

2



Databases

High

The information or data is

1

1

1

Other





from a recognized data
collection/repository where
data are peer-reviewed by
experts in the field, are
broadly available to the
public for review and use
OR includes references to
the original sources.









Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Sum of scores:

7

5

7

Midi

Medium

l.im

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting
Factors:

1.4

Overall
Score

(Rounded):

1.4

1 ;i ikI 1 "

1 "and : ^

: 'and '





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Water Solubility reported by this reference.
Cited reference: PhysProp

Page 38 of 63


-------
Studv

NLM (2021). Pubchcm: 1,3-Disiloxancdiol, 1,1,3,3-tetramcthyl-. CAS registry number: 1118-15-6.

Reference:

HERO ID: 7997877















Qualitative









Domain

Metric

Determination (i.e.,

High, Medium,
Low, Unacceptable,
or Not Rated |NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score



Representativeness

High

Data are measured or
estimated for the
subject chemical
substance.

1

1

1



Appropriateness

High

Measured data are
consistent with the

1

1

1

Substance





subject chemical
substance structural
features (e.g., presence
of certain functional
groups) or other
physical/chemical
properties or behaviors.









Reliability /

Medium

There is no indication

2

1

2



Unbiased (Method
Objectivity)



that the methodology
for producing the
information was biased







Test

Reliability





towards a particular
product or outcome.







Reliability /
Analytical Method

Medium

The analytical method
is unknown but is likely
to be appropriate based
on the data's inclusion
in a peer-reviewed/
recognized database or
other secondary source.

2

1

2



Databases

Medium

Data is from a publicly
available secondary
source with references

2

1

2

Other





to non-peer reviewed
original sources.









Models

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Sum of scores:

8

5

8

Midi

Medium

1 A»\X

()\ erall Score = Sum
of Weighted
Scores/Sum of Metric
\\ eighting Factors:

1.6

Overall
Score

(Rounded):

1.6

1 and 1 "

1 "and 2 ^

:.^aiid ^





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Water Solubility reported by this reference.
Cited reference: EPA DSSTox

Page 39 of 63


-------
Study
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for tctramcthyl-l,3-disiloxancdiol. CAS
Registry Number: 1118-15-6. HERO ID: 7994661

Domain

Metric

Qualitative
Determination

(/.t'., High,
Medium. Low,
Unacceptable, or
Not Rated |NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1

Appropriateness

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Test

Reliability

Reliability / Unbiased
(Method Objectivity)

Medium

There is no indication that
the methodology for
producing the information
was biased towards a
particular product or
outcome.

2

1

2

Reliability / Analytical
Method

Medium

The analytical method is
unknown but is likely to be
appropriate based on the
data's inclusion in a peer-
reviewed/recognized
database or other secondary
source.

2

1

2

Other

Databases

High

The information or data is
from a recognized data
collection/repository where
data are peer-reviewed by
experts in the field, are
broadly available to the
public for review and use
OR includes references to
the original sources.

1

1

1

Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Sum of scores:

6

4

6

Midi

Medium

I.HM

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting
Factors:

1.5

Overall
Score

(Rounded):

1.5

1 ;iihJ 1

1 "and : ^

2 'and "





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Refractive Index reported by this reference.

Cited reference: Hyde; Journal of the American Chemical Society; vol. 75; (1953); p. 2166, View inReaxys

Page 40 of 63


-------
Studv

U.S. EPA (U.S. Environmental Protection Aucncv). (2012). Estimation Programs Interface Suite™ for

Reference:

Microsoft Windows.

v 4.11 1 Comi)uter Prouraml. Washington. DC. HERO ID:2347246







Qualitative













Determination (i.e.,



Metric
Score

Metric

Weighted

Score

Domain

Metric

High, Medium,
Low, Unacceptable,
or Not Rated |NR|)

Comments

Weighting
Factor

Substance

Representativeness

NR

The metric is not applicable
to this study type (SAR).

NR

1

NR

Appropriateness

NR

The metric is not applicable
to this study type (SAR).

NR

1

NR

Test

Reliability / Unbiased
(Method Objectivity)

NR

The metric is not applicable
to this study type (SAR).

NR

1

NR

Reliability

Reliability /
Analytical Method

NR

The metric is not applicable
to this study type (SAR).

NR

1

NR



Databases

NR

The metric is not applicable
to this study type (SAR).

NR

1

NR



Models

High

The models in EPI Suite™
have defined endpoints.
Chemical domain and
performance statistics for
each model are known, and
unambiguous algorithms are
available in the EPI Suite™
documentation and/or cited
references to establish their
scientific validity. Many EPI
Suite™ models have

1

1

1

Other





correlation coefficients >0.7,











cross-validated correlation
coefficients >0.5, and
standard error values <0.3;
however, correlation
coefficients (r2, q2) for the
regressions of some
environmental fate models
{i.e., BIOWIN) are lower, as
expected, compared to
regressions which have
specific experimental values
such as water solubility or
log Kow (octanol-water
partition coefficient).







Sum of scores:

1

1

1

Midi

Medium

1 A»\X

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting Factors:

1

Overall
Score

(Rounded):

1

1 and 1 "

1 ~ and

: ^ mid '





Overall
Quality
Level:

High

Page 41 of 63


-------
ametliyItrisiloxaiiediol (CASRN 3663-50-1) Data Extraction Tables

Table 1. Physical State Study Summary
No Physical State data were identified for this chemical.

Table 2. Physical Properties Study Summary
No Physical Properties data were identified for this chemical.

Table 3. Melting Point Study Summary

Study Type

Substance
Purity

Result

Comments

Affiliated Reference

Data Quality
Evaluation Results

Experimental

NR

-23 to -1.9 °C

2 values were reported in Reaxys.

(Elsevier. 2021a)

High

Table 4. Boiling Point Study Summary

Study Type

Substance
Purity

Result

Comments

Affiliated
Reference

Data Quality
Evaluation Results

Experimental

NR

79-91°C

5 values were reported in Reaxys; 3 were in the range of 79-91°C at
2-3 torr; the other two were 106 °C at 6 torr and 72-74°C at 0.3 ton-

(Elsevier.
2021a)

High

Table 5. Density Study Summary

Study Type

Study
Details

Reference
Substance

Temperature

Result

Comments

Affiliated
Reference

Data Quality
Evaluation Results

Experimental







0.991 to
1.0127 g/cm3

5 values were reported in Reaxys in the
range of 0.991- 1.0127 g/cm3, at 20-25 °C
(reference temperature 4 °C)

(Elsevier.

2021a)

High

Table 6. Vapor Pressure Study Summary

No Vapor Pressure data were identified for this chemical.

Table 7. Vapor Density Study Summary

No Vapor Density data were identified for this chemical.

Table 8. Water Solubility Study Summary

No Water Solubility data were identified for this chemical.

Page 42 of 63


-------
Table 9. Octanol Water Coefficient (logKow) Study Summary
No Octanol Water Coefficient (logKow) data were identified for this chemical.

Table	ry's Law Constant Study Summary

No Henrys Law data were identified for this chemical.

Table 11. Flash Point Study Summary

No Flash Point data were identified for this chemical.

Table 12. Auto Flammability Study Summary
No Autoflammability data were identified for this chemical.

Table 13. Viscosity Study Summary
No Viscosity data were identified for this chemical.

Study Type

Apparatus

Result

Comments

Affiliated Refcrcnec

Data Quality Evaluation Results

Experimental

20-25 °C

1.405-1.409

6 values were reported in Reaxys in the range of 1.405-1.409,
589 nm

(Elsevier. 2021a)

High

Table 15. Dielectric Constant Study Summary
No Dielectric Constant data were identified for this chemical.

Page 43 of 63


-------
EPI Suite1M Model Outputs
(U.S. EPA. 2012)

SMILES: [Si](0)(0[Si](0[Si](0)(C)C)(C)C)(C)C
CHEM: 1,5-Trisiloxanediol, 1,1,3,3,5,5-hexamethyl-
MOL FOR: C6 H20 04 Si3
MOL WT: 240.48

	EPI SUMMARY (v4.11)	

Physical Property Inputs:

Log Kow (octanol-water):	

Boiling Point (°C):	

Melting Point (°C):	

Vapor Pressure (mm Hg):	

Water Solubility (mg/L):	

Henry LC (atm-m3/mole):	

Log Octanol-Water Partition Coef (SRC):

Log Kow (KOWWIN vl.68 estimate) = 3.20

Boiling Pt, Melting Pt, Vapor Pressure Estimations (MPBPVP vl.43):

Boiling Pt (°C): 276.03 (Adapted Stein & Brown method)

Melting Pt (°C): 35.49 (Mean or Weighted MP)

VP(mm Hg, 25 °C): 0.000289 (Modified Grain method)

VP (Pa, 25 °C): 0.0385 (Modified Grain method)

Subcooled liquid VP: 0.000359 mm Hg (25 °C, Mod-Grain method): 0.0478 Pa (25 °C, Mod-Grain
method)

Water Solubility Estimate from Log Kow (WSKOW vl.42):

Water Solubility at 25 °C (mg/L): 20.67
log Kow used: 3.20 (estimated)
no-melting pt equation used

Water Sol Estimate from Fragments:

Wat Sol (vl.01 est) = 7163.9 mg/L

ECOSAR Class Program (ECOSAR vl. 11):

Class(es) found:

Neutral Organics

Henrys Law Constant (25 °C) [HENRYWIN v3.20]:

Bond Method: 2.18E-008 atm-m3/mole (2.21E-003 Pa-m3/mole)

Group Method: Incomplete

For Henry LC Comparison Purposes:

User-Entered Henry LC: not entered

Henrys LC [via VP/WSol estimate using User-Entered or Estimated values]:

HLC: 4.424E-006 atm-m3/mole (4.483E-001 Pa-m3/mole)

VP: 0.000289 mm Hg (source: MPBPVP)

WS: 20.7 mg/L (source: WSKOWWIN)

Page 44 of 63


-------
Log Octanol-Air Partition Coefficient (25 °C) [KOAWIN vl.10]:

Log Kow used: 3.20 (KowWin est)

Log Kaw used: -6.050 (HenryWin est)

Log Koa (KOAWIN vl.10 estimate): 9.250

Log Koa (experimental database): None

Probability of Rapid Biodegradation (BIOWIN v4.10):

Biowinl (Linear Model): 0.6331

Biowin2 (Non-Linear Model): 0.3998

Expert Survey Biodegradation Results:

Biowin3 (Ultimate Survey Model): 2.6677 (weeks-months)

Biowin4 (Primary Survey Model): 3.5008 (days-weeks)

MITI Biodegradation Probability:

Biowin5 (MITI Linear Model): -0.0008

Biowin6 (MITI Non-Linear Model): 0.0134

Anaerobic Biodegradation Probability:

Biowin7 (Anaerobic Linear Model): 0.3587

Ready Biodegradability Prediction: NO

Hydrocarbon Biodegradation (BioHCwin vl.01):

Structure incompatible with current estimation method!

Sorption to aerosols (25 °C)[AEROWIN vl.00]:

Vapor pressure (liquid/subcooled): 0.0479 Pa (0.000359 mm Hg)

Log Koa (Koawin est): 9.250

Kp (particle/gas partition coef. (m3/ug)):

Mackay model: 6.27E-005

Octanol/air (Koa) model: 0.000437

Fraction sorbed to airborne particulates (phi):

Junge-Pankow model: 0.00226

Mackay model: 0.00499

Octanol/air (Koa) model: 0.0337

Atmospheric Oxidation (25 °C) [AopWin vl.92]:

Hydroxyl Radicals Reaction:

OVERALL OH Rate Constant = 7.7976 E-12 cm3/molecule-sec

Half-Life = 1.372 Days (12-hr day; 1.5E6 OH/cm3)

Half-Life = 16.460 Hrs

Ozone Reaction:

No Ozone Reaction Estimation

Fraction sorbed to airborne particulates (phi):

0.00362 (Junge-Pankow, Mackay avg)

0.0337 (Koa method)

Note: the sorbed fraction may be resistant to atmospheric oxidation

Soil Adsorption Coefficient (KOCWIN v2.00):

Koc: 2644 L/kg (MCI method)

Log Koc: 3.422 (MCI method)

Koc: 598.2 L/kg (Kow method)

Page 45 of 63


-------
Log Koc: 2.777 (Kow method)

Aqueous Base/Acid-Catalyzed Hydrolysis (25 °C) [HYDROWIN v2.00]:
Rate constants can NOT be estimated for this structure!

Bioaccumulation Estimates (BCFBAF v3.01):

Log BCF from regression-based method = 1.777 (BCF = 59.85 L/kg wet-wt)
Log Biotransformation Half-life (HL) = 0.2998 days (HL = 1.994 days)
Log BCF Arnot-Gobas method (upper trophic) = 2.145 (BCF = 139.7)
Log BAF Arnot-Gobas method (upper trophic) = 2.145 (BAF = 139.7)
log Kow used: 3.20 (estimated)

Volatilization from Water:

Henry LC: 2.18E-008 atm-m3/mole (estimated by Bond SAR Method)
Half-Life from Model River: 4.165E+004 hours (1735 days)

Half-Life from Model Lake: 4.545E+005 hours (1.894E+004 days)

Removal in Wastewater Treatment:

Total removal 7.80 percent
Total biodegradation: 0.14 percent
Total sludge adsorption: 7.66 percent
Total to Air: 0.00 percent
(using 10000 hr Bio P,A,S)

Level III Fugacity Model:

Mass Amount Half-Life Emissions

(percent)

(hr) (kg/hr)



Air

0.134 32.9

1000

Water

12 900

1000

Soil

86 1.8E+003

1000

Sediment

1.81 8.1E+003

0

Persistence

Time: 1.7E+003 hr



Page 46 of 63


-------
bles

Stud>
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for 1,1,3,3,5,5- hcxamcthyltrisiloxanc-l,5-diol.
CAS Rcgistrv Number: 3663-50-1. HERO ID: 7992314

Domain

Metric

Qualitative
Determination (i.e.,
High, Medium, Low,
Unacceptable, or Not
Rated NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1

Appropriateness

High

Measured data are
consistent with the subject
chemical substance
structural features (e.g.,
presence of certain
functional groups) or other
physical/ chemical
properties or behaviors.

1

1

1

Test

Reliability

Reliability /
Unbiased (Method
Objectivity)

Medium

There is no indication that
the methodology for
producing the information
was biased towards a
particular product or
outcome.

2

1

2

Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to be
appropriate based on the
data's inclusion in a peer-
reviewed/ recognized
database or other
secondary source.

2

1

2

Other

Databases

High

The information or data is
from a recognized data
collection/repository where
data are peer-reviewed by
experts in the field, are
broadly available to the
public for review and use
OR includes references to
the original sources.

1

1

1



Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Sum of scores:

7

5

7

Midi

Medium

Low

()\ erall Score = Sum of
\\ eighted Scores/Sum of
Mel ric Weighting
l-aclors:

1.4

Overall
Score

(Rounded):

1.4

1 and 1

1 ~ and : ^

2 'and '





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Melting Point reported by this reference.

Cited reference: Patent; Union Carbide; FR1399256; (1965); (A); Chem.Abstr.; vol. 63; nb. 16383e; (1965); Chem.Abstr.;
vol. 63; nb. 16383e; (1965); Sokolow; Zhurnal Obshchei Khimii; vol. 29; (1959); p. 258,261, 263; engl. Ausg. S. 262, 265,
266.

Page 47 of 63


-------
Study
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for 1,1,3,3,5,5- hcxamcthyltrisiloxanc-1,5-
diol. CAS Registry Number: 3663-50-1. HERO ID: 7992314

Domain

Metric

Qualitative
Determination

(/.t'., High,
Medium, Low,
Unacceptable, or
Not Rated NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1

Appropriateness

High

Measured data are
consistent with the subject
chemical substance
structural features (e.g.,
presence of certain
functional groups) or other
physical/chemical
properties or behaviors.

1

1

1

Test

Reliability

Reliability /
Unbiased (Method
Objectivity)

Medium

There is no indication that
the methodology for
producing the information
was biased towards a
particular product or
outcome.

2

1

2

Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to be
appropriate based on the
data's inclusion in a peer-
reviewed/recognized
database or other secondary
source.

2

1

2

Other

Databases

High

The information or data is
from a recognized data
collection/repository where
data are peer-reviewed by
experts in the field, are
broadly available to the
public for review and use
OR includes references to
the original sources.

1

1

1



Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Sum of scores:

7

5

7

Midi

Medium

1 .o\\

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting
Factors:

1.4

Overall
Score

(Rounded):

1.4

1 ;n id 1 "

1 "and : ^

: ^ and ^





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Boiling Point reported by this reference.

Cited references: Zachernyuk et al. 1985; Kaufman et al. 1970; Union Carbide Patent 1965; Harris 1963; Andrianov et al.
1962

Page 48 of 63


-------
Study
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for 1,1,3,3,5,5- hcxamcthyltrisiloxanc-1,5-
diol. CAS Registry Number: 3663-50-1. HERO ID: 7992314

Domain

Metric

Qualitative
Determination (i.e.,

High, Medium,
Low, Unacceptable,
or Not Rated NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or
estimated for the
subject chemical
substance.

1

1

1

Appropriateness

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Test

Reliability

Reliability /
Unbiased (Method
Objectivity)

Medium

There is no indication
that the methodology
for producing the
information was biased
towards a particular
product or outcome.

2

1

2

Reliability /
Analytical Method

Medium

The analytical method
is unknown but is likely
to be appropriate based
on the data's inclusion
in a peer-reviewed/
recognize d database or
other secondary source.

2

1

2

Other

Databases

High

The information or data
is from a recognized
data

collection/repository
where data are peer-
reviewed by experts in
the field, are broadly
available to the public
for review and use OR
includes references to
the original sources.

1

1

1

Models

NR

Rating of this factor is
not applicable to this
kind of information.

NR

NR

NR

Sum of scores:

6

4

6

Midi

Medium

1 A»\X

()\ erall Score = Sum
of Weighted
Scores/Sum of Metric
\\ eighting Factors:

1.5

Overall
Score

(Rounded):

1.5

1 and 1 "

1 ~ and

:.^aiid ^





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Density reported by this reference.

Cited references: Voronkov et al. 1970; Kaufman and Karlin 1970; Union Carbide Patent 1965; Andrianov et al. 1962;
Sokolow 1959.

Page 49 of 63


-------
Study
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for 1,1,3,3,5,5- hcxamcthyltrisiloxanc-l,5-diol.
CAS Rcgistrv Number: 3663-50-1. HERO ID: 7992314

Domain

Metric

Qualitative
Determination (i.e.,

High, Medium,
Low, Unacceptable,
or Not Rated NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1

Appropriateness

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Test

Reliability

Reliability / Unbiased
(Method Objectivity)

Medium

There is no indication that
the methodology for
producing the information
was biased towards a
particular product or
outcome.

2

1

2

Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to be
appropriate based on the
data's inclusion in a peer-
reviewed/recognized
database or other secondary
source.

2

1

2

Other

Databases

High

The information or data is
from a recognized data
collection/repository where
data are peer-reviewed by
experts in the field, are
broadly available to the
public for review and use
OR includes references to
the original sources.

1

1

1

Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Sum of scores:

6

4

6

1 huh

Medium

1 A»\X

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting Factors:

1.5

Overall
Score

(Rounded):

1.5

1 and
1 "

1 "and : ^

2 ^ and ^





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Refractive Index reported by this reference.

Cited references: Voronokov et al. 1971; Kaufman and Karlin 1970; Union Carbide Patent 1965; Harris 1963; Andrianov
1962; Sokolow 1959.

Page 50 of 63


-------
Studv

U.S. EPA (U.S. Environmental Protection Aucncv). (2012). Estimation Programs Interface Suite™ for

Reference:

Microsoft^; Windows.

v 4.11 IComnutcr Program 1. Washington. DC. HERO ID:2347246







Qualitative













Determination (i.e.,



Metric
Score

Metric

Weighted

Score

Domain

Metric

High, Medium, Low,
Unacccptable, or Not
Rated |NR|)

Comments

Weighting
Factor

Substance

Representativeness

NR

The metric is not applicable
to this study type (SAR).

NR

1

NR

Appropriateness

NR

The metric is not applicable
to this study type (SAR).

NR

1

NR

Test

Reliability / Unbiased
(Method Objectivity)

NR

The metric is not applicable
to this study type (SAR).

NR

1

NR

Reliability

Reliability / Analytical
Method

NR

The metric is not applicable
to this study type (SAR).

NR

1

NR



Databases

NR

The metric is not applicable
to this study type (SAR).

NR

1

NR



Models

High

The models in EPI Suite™
have defined endpoints.
Chemical domain and
performance statistics for
each model are known, and
unambiguous algorithms are
available in the EPI Suite™
documentation and/or cited
references to establish their
scientific validity. Many
EPI Suite™ models have
correlation coefficients

1

1

1

Other





>0.7, cross-validated
correlation coefficients
>0.5, and standard error
values <0.3; however,
correlation coefficients (r2,
q2) for the regressions of
some environmental fate
models (i.e., BIO WIN) are
lower, as expected,
compared to regressions
which have specific
experimental values such as
water solubility or log Kow
(octanol-water partition
coefficient).







Sum of scores:

1

1

1

Midi

Medium

1 A»\X

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting Factors:

1

Overall
Score

(Rounded):

1

1 and 1 "

1 "and : '

: ^ ;md ^





Overall
Quality
Level:

High

Page 51 of 63


-------
Octamethyltetrasiloxanedi \SRN 3081 -07-0) Data Extraction Tables

Table 1. Physical State Study Summary
No Physical State data were identified for this chemical.

Table 2. Physical Properties Study Summary
No Physical Properties data were identified for this chemical.

Table 3. Melting Point Study Summary

Study Type

Substance
Purity

Result

Comments

Affiliated Reference

Data Quality
Evaluation Results

Experimental

NR

-5 °C

NR

(Elsevier. 2021b)

High

Table 4. Boiling Point Study Summary

Study Type

Substance
Purity

Result

Comments

Affiliated Reference

Data Quality
Evaluation Results

Experimental

NR

97-100 °C

1 value reported in Reaxys at 2 torr

(Elsevier. 2021b)

High

Experimental

NR

86-88 °C

1 value reported in Reaxys at 0.4 ton-

(Elsevier. 2021b)

High

Table 5. Density Study Summary

Study Type

Study
Details

Reference
Substance

Temperature

Result

Comments

Affiliated
Reference

Data Quality
Evaluation
Results

Experimental







0.9881-0.9886 g/cm3

2 values reported in Reaxys;
reference temperature 4 °C,
measurement temperature 20 ° C

(Elsevier. 2021b)

High

Table 6. Vapor Pressure Study Summary

No Vapor Pressure data were identified for this chemical.

Table 7. Vapor Density Study Summary

No Vapor Density data were identified for this chemical.

Page 52 of 63


-------
Table 8. Water Solubility Study Summary

No Water Solubility data were identified for this chemical.

Table 9. Octanol Water Coefficient (logKow) Study Summary
No Octanol Water Coefficient (logKow) data were identified for this chemical.

Table	ry's Law Constant Study Summary

No Henrys Law data were identified for this chemical.

Table 11. Flash Point Study Summary

No Flash Point data were identified for this chemical.

Table 12. Auto Flammability Study Summary
No Autoflammability data were identified for this chemical.

Table 13. Viscosity Study Summary
No Viscosity data were identified for this chemical.

Table 14. Refractive Index Study Summary

Study Type

Apparatus

Result

Comments

Affiliated Reference

Data Quality
Evaluation
Results

Experimental

20-25 °C

1.4054-1.4088

3 values were reported in Reaxys, 589 nm

(Elsevier. 2021b)

High

Table 15. Dielectric Constant Study Summary
No Dielectric Constant data were identified for this chemical.

Page 53 of 63


-------
EPI Suite1M Model Outputs
(U.S. EPA. 2012)

SMILES: [Si](0)(0[Si](0[Si](0[Si](0)(C)C)(C)C)(C)C)(C)C
CHEM: 1,7-Tetrasiloxanediol, 1,1,3,3,5,5,7,7-octamethyl-
MOL FOR: C8 H26 05 Si4
MOL WT: 314.64

	EPI SUMMARY (v4.11)	

Physical Property Inputs:

Log Kow (octanol-water):	

Boiling Point (°C):	

Melting Point (°C):	

Vapor Pressure (mm Hg):	

Water Solubility (mg/L):	

Henry LC (atm-m3/mole):	

Log Octanol-Water Partition Coef (SRC):

Log Kow (KOWWIN vl.68 estimate) = 4.65

Boiling Pt, Melting Pt, Vapor Pressure Estimations (MPBPVP vl.43):

Boiling Pt (°C): 306.15 (Adapted Stein & Brown method)

Melting Pt (°C): 40.55 (Mean or Weighted MP)

VP (mm Hg, 25 °C): 3.53E-005 (Modified Grain method)

VP (Pa, 25 °C): 0.0047 (Modified Grain method)

Subcooled liquid VP: 4.88E-005 mm Hg (25 °C, Mod-Grain method)

: 0.0065 Pa (25 °C, Mod-Grain method)

Water Solubility Estimate from Log Kow (WSKOW vl.42):

Water Solubility at 25 °C (mg/L): 3.017
log Kow used: 4.65 (estimated)
no-melting pt equation used

Water Sol Estimate from Fragments:

Wat Sol (vl.01 est) = 301.53 mg/L

ECOSAR Class Program (ECOSAR vl. 11):

Class(es) found:

Neutral Organics

Henrys Law Constant (25 °C) [HENRYWIN v3.20]:

Bond Method: 3.00E-008 atm-m3/mole (3.04E-003 Pa-m3/mole)

Group Method: Incomplete

For Henry LC Comparison Purposes:

User-Entered Henry LC: not entered

Henrys LC [via VP/WSol estimate using User-Entered or Estimated values]:
HLC: 4.844E-006 atm-m3/mole (4.908E-001 Pa-m3/mole)

VP: 3.53E-005 mm Hg (source: MPBPVP)

WS: 3.02 mg/L (source: WSKOWWIN)

Page 54 of 63


-------
Log Octanol-Air Partition Coefficient (25 °C) [KOAWIN vl.10]:

Log Kow used: 4.65 (KowWin est)

Log Kaw used: -5.911 (HenryWin est)

Log Koa (KOAWIN vl.10 estimate): 10.561

Log Koa (experimental database): None

Probability of Rapid Biodegradation (BIOWIN v4.10):

Biowinl (Linear Model): 0.5978

Biowin2 (Non-Linear Model): 0.1886

Expert Survey Biodegradation Results:

Biowin3 (Ultimate Survey Model): 2.5039 (weeks-months)

Biowin4 (Primary Survey Model): 3.3938 (days-weeks)

MITI Biodegradation Probability:

Biowin5 (MITI Linear Model): -0.2206

Biowin6 (MITI Non-Linear Model): 0.0017

Anaerobic Biodegradation Probability:

Biowin7 (Anaerobic Linear Model): 0.1995

Ready Biodegradability Prediction: NO

Hydrocarbon Biodegradation (BioHCwin vl.01):

Structure incompatible with current estimation method!

Sorption to aerosols (25 °C)[AEROWIN vl.00]:

Vapor pressure (liquid/subcooled): 0.00651 Pa (4.88E-005 mm Hg)

Log Koa (Koawin est): 10.561

Kp (particle/gas partition coef. (m3/ug)):

Mackay model: 0.000461

Octanol/air (Koa) model: 0.00893

Fraction sorbed to airborne particulates (phi):

Junge-Pankow model: 0.0164

Mackay model: 0.0356

Octanol/air (Koa) model: 0.417

Atmospheric Oxidation (25 °C) [AopWin vl.92]:

Hydroxyl Radicals Reaction:

OVERALL OH Rate Constant = 8.0968 E-12 cm3/molecule-sec

Half-Life = 1.321 Days (12-hr day; 1.5E6 OH/cm3)

Half-Life = 15.852 Hrs

Ozone Reaction:

No Ozone Reaction Estimation

Fraction sorbed to airborne particulates (phi):

0.026 (Junge-Pankow, Mackay avg)

0.417 (Koa method)

Note: the sorbed fraction may be resistant to atmospheric oxidation

Soil Adsorption Coefficient (KOCWIN v2.00):

Koc: 2.052E+004 L/kg (MCI method)

Log Koc: 4.312 (MCI method)

Koc: 1.085E+004 L/kg (Kow method)

Page 55 of 63


-------
Log Koc: 4.035 (Kow method)

Aqueous Base/Acid-Catalyzed Hydrolysis (25 °C) [HYDROWIN v2.00]:
Rate constants can NOT be estimated for this structure!

Bioaccumulation Estimates (BCFBAF v3.01):

Log BCF from regression-based method = 2.737 (BCF = 545.8 L/kg wet-wt)
Log Biotransformation Half-life (HL) = 1.0470 days (HL = 11.14 days)
Log BCF Arnot-Gobas method (upper trophic) = 3.344 (BCF = 2208)
Log BAF Arnot-Gobas method (upper trophic) = 3.425 (BAF = 2661)
log Kow used: 4.65 (estimated)

Volatilization from Water:

Henry LC: 3E-008 atm-m3/mole (estimated by Bond SAR Method)
Half-Life from Model River: 3.462E+004 hours (1442 days)

Half-Life from Model Lake: 3.778E+005 hours (1.574E+004 days)

Removal in Wastewater Treatment:

Total removal: 63.62 percent
Total biodegradation: 0.58 percent
Total sludge adsorption: 63.05 percent
Total to Air: 0.00 percent
(using 10000 hr Bio P,A,S)

Level III Fugacity Model:

Mass Amount Half-Life Emissions

(percent)

(hr) (kg/hr)



Air

0.157 31.7

1000

Water

0.3 900

1000

Soil

77.5 1.8E+003

1000

Sediment

12.1 8.1E+003

0

Persistence

Time: 1.84E+003 hr



Page 56 of 63


-------
Data Evaluation Tables

Study
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for 1,1,3,3,5,5,7,7- octamcthyltctrasiloxanc-
1,7-diol. CAS Registry Number: 3081-07-0. HERO ID: 7991715

Domain

Metric

Qualitative
Determination (i.e.,

High, Medium,
Low, Unacceptable,
or Not Rated |NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1

Appropriateness

High

Measured data are
consistent with the subject
chemical substance
structural features (e.g.,
presence of certain
functional groups) or other
physical/chemical
properties or behaviors.

1

1

1

Test

Reliability

Reliability /
Unbiased (Method
Objectivity)

Medium

There is no indication that
the methodology for
producing the information
was biased towards a
particular product or
outcome.

2

1

2

Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to
be appropriate based on
the data's inclusion in a
peer-reviewed/
recognized database or
other secondary source.

2

1

2

Other

Databases

High

The information or data is
from a recognized data
collection/repositor y
where data are peer-
reviewed by experts in the
field, are broadly available
to the public for review
and use OR includes
references to the original
sources.

1

1

1



Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Sum of scores:

7

5

7

Midi

Medium

1 ,o\\

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting
Factors:

1.4

Overall
Score

(Rounded):

1.4

1 ;ind 1 "

1 "and : ^

2.' and ^





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Melting Point reported by this reference.

Cited reference: Zhurnal Obshchei Khimii; vol. 29; (1959); p. 258,261, 263; engl. Ausg. S. 262, 265, 266,

Page 57 of 63


-------
Study
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for 1,1,3,3,5,5,7,7- octamcthyltctrasiloxanc-
1,7-diol. CAS Rcgistrv Number: 3081-07-0. HERO ID: 7991715

Domain

Metric

Qualitative
Determination (i.e.,
High, Medium, Low,
Unacceptable, or Not
Rated |NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1

Appropriateness

High

Measured data are
consistent with the subject
chemical substance
structural features (e.g.,
presence of certain
functional groups) or other
physical/chemical
properties or behaviors.

1

1

1

Test

Reliability

Reliability /
Unbiased (Method
Objectivity)

Medium

There is no indication that
the methodology for
producing the information
was biased towards a
particular product or
outcome.

2

1

2

Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to be
appropriate based on the
data's inclusion in a peer-
reviewed/recognized
database or other secondary
source.

2

1

2

Other

Databases

High

The information or data is
from a recognized data
collection/repository where
data are peer-reviewed by
experts in the field, are
broadly available to the
public for review and use
OR includes references to
the original sources.

1

1

1



Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Sum of scores:

7

5

7

Midi

Medium

l.ou

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting Factors:

1.4

Overall
Score

(Rounded):

1.4

1 ;n id 1 "

1and

2 ^ and ^





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Boiling Point reported by this reference.

Cited reference: Andrianov,K.A. et al.; Bulletin of the Academy of Sciences of the USSR Division of Chemical Science;
(1962); p. 2144-2146; Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya; (1962); p. 2243-2245.

Page 58 of 63


-------
Study
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for 1,1,3,3,5,5,7,7- octamcthyltctrasiloxanc-
1,7-diol. CAS Registry Number: 3081 -07-0. HERO ID: 7991715

Domain

Metric

Qualitative
Determination (i.e.,
High, Medium, Low,
Unacceptable, or Not
Rated |NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1

Appropriateness

High

Measured data are
consistent with the subject
chemical substance
structural features (e.g.,
presence of certain
functional groups) or other
physical/ chemical
properties or behaviors.

1

1

1

Test

Reliability

Reliability /
Unbiased (Method
Objectivity)

Medium

There is no indication that
the methodology for
producing the information
was biased towards a
particular product or
outcome.

2

1

2

Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to be
appropriate based on the
data's inclusion in a peer-
reviewed/ recognized
database or other secondary
source.

2

1

2

Other

Databases

High

The information or data is
from a recognized data
collection/repository where
data are peer-reviewed by
experts in the field, are
broadly available to the
public for review and use
OR includes references to
the original sources.

1

1

1



Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Sum of scores:

7

5

7

Midi

Medium

l.ou

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting Factors:

1.4

Overall
Score

(Rounded):

1.4

1 ;n id 1 "

1 "and : ^

:.^ind '





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Boiling Point reported by this reference.
Cited reference: Harris; Journal of the Chemical Society; (1963); p. 5978, 5981.

Page 59 of 63


-------
Study
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for 1,1,3,3,5,5,7,7- octamcthyltctrasiloxanc-
1,7-diol. CAS Rcmstrv Number: 3081-07-0. HERO ID: 7991715

Domain

Metric

Qualitative
Determination

(/.t'., High,
Medium, Low,
Unacceptable, or
Not Rated NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or
estimated for the subject
chemical substance.

1

1

1

Appropriateness

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Test

Reliability

Reliability /
Unbiased (Method
Objectivity)

Medium

There is no indication that
the methodology for
producing the information
was biased towards a
particular product or
outcome.

2

1

2

Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to be
appropriate based on the
data's inclusion in a peer-
reviewed/ recognized
database or other secondary
source.

2

1

2

Other

Databases

High

The information or data is
from a recognized data
collection/repository where
data are peer-reviewed by
experts in the field, are
broadly available to the
public for review and use
OR includes references to
the original sources.

1

1

1

Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Sum of scores:

6

4

6

Midi

Medium

1 A»\X

0\erall Score = Sum of
\\ eighted Scores/Sum of
Medic Weighting Factors:

1.5

Overall
Score

(Rounded):

1.5

1 and 1 "

1 "and : ^

: ^ and ^





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Density reported by this reference.

Cited references: Andrianov,K.A. et al.; Bulletin of the Academy of Sciences of the USSR Division of Chemical Science;
(1962); p. 2144-2146; Sokolow; Zhurnal Obshchei Khimii; vol. 29; (1959); p. 258,261, 263; engl. Ausg. S. 262, 265, 266

Page 60 of 63


-------
Study
Reference:

Elsevier (2021). Rcaxvs: physical-chemical property data for 1,1,3,3,5,5,7,7- octamcthyltctrasiloxanc-
1,7-diol. CAS Rcgistrv Number: 3081-07-0. HERO ID: 7991715

Domain

Metric

Qualitative
Determination

(i.e., Hi«h,
Medium, Low,
Unacceptable, or
Not Rated |NR|)

Comments

Metric
Score

Metric
Weighting
Factor

Weighted

Score

Substance

Representativeness

High

Data are measured or estimated
for the subject chemical
substance.

1

1

1

Appropriateness

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Test

Reliability

Reliability /
Unbiased (Method
Objectivity)

Medium

There is no indication that the
methodology for producing the
information was biased towards
a particular product or
outcome.

2

1

2

Reliability /
Analytical Method

Medium

The analytical method is
unknown but is likely to be
appropriate based on the data's
inclusion in a peer-reviewed/
recognized database or other
secondary source.

2

1

2

Other

Databases

High

The information or data is from
a recognized data
collection/repository where
data are peer-reviewed by
experts in the field, are broadly
available to the public for
review and use OR includes
references to the original
sources.

1

1

1

Models

NR

Rating of this factor is not
applicable to this kind of
information.

NR

NR

NR

Sum of scores:

6

4

6

Midi

Medium

1 A»\X

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting Factors:

1.5

Overall
Score
(Rounded):

1.5

1 and
1 "

1 ~ and

: ^ and ^





Overall
Quality
Level:

High

The reviewer agreed with the overall rating for the Refractive Index reported by this reference.

Cited references: Harris 1963; Andrianov,K.A. et al.; Bulletin of the Academy of Sciences of the

USSR Division of Chemical Science; (1962); p. 2144 - 2146; Sokolow; Zhurnal Obshchei Khimii; vol. 29; (1959); p.

258,261, 263; engl. Ausg. S. 262, 265, 266

Page 61 of 63


-------
Studv

U.S. EPA (U.S. Environmental Protection Aucncv). (2012). Estimation Programs Interface Suite™ for

Reference:

MicrosoftX Windows,

v 4.11 [Computer Program]. Washington, DC. HERO ID:2347246



Domain

Metric

Qualitative

Comments

Metric

Metric

Weighted





Determination



Score

Weighting

Score





(/.t'., High,





Factor







Medium. Low,













Unacceptable, or
Not Rated |NR|)









Substance

Representativeness

NR

The metric is not applicable
to this study type (SAR).

NR

1

NR

Appropriateness

NR

The metric is not applicable
to this study type (SAR).

NR

1

NR

Test

Reliability / Unbiased
(Method Objectivity)

NR

The metric is not applicable
to this study type (SAR).

NR

1

NR

Reliability

Reliability /
Analytical Method

NR

The metric is not applicable
to this study type (SAR).

NR

1

NR



Databases

NR

The metric is not applicable
to this study type (SAR).

NR

1

NR



Models

High

The models in EPI Suite™
have defined endpoints.
Chemical domain and
performance statistics for
each model are known, and
unambiguous algorithms are
available in the EPI Suite™
documentation and/or cited
references to establish their
scientific validity. Many EPI
Suite™ models have

1

1

1

Other





correlation coefficients >0.7,











cross-validated correlation
coefficients >0.5, and
standard error values <0.3;
however, correlation
coefficients (r2, q2) for the
regressions of some
environmental fate models
(i.e., BIO WIN) are lower, as
expected, compared to
regressions which have
specific experimental values
such as water solubility or
log Kow (octanol-water
partition coefficient).







Sum of scores:

1

1

1

1 1 lull

Malmm

1 ,o\\

Overall Score = Sum of
Weighted Scores/Sum of
Metric Weighting Factors:

1

Overall
Score
(Rounded):

1

1 and 1."

1 ~and : ^

1 ^ ;md ^





Overall
Quality
Level:

High

Page 62 of 63


-------
References

Elsevier. (2021a). Reaxys: physical-chemical property data for l,l,3,3,5,5-hexamethyltrisiloxane-l,5-
diol. CAS Registry Number: 3663-50-1. Available online at

https://heronet.epa.gov/heronet/index.cfm/reference/download/reference id/7992314C3 - 2976
Elsevier. (2021b). Reaxys: physical-chemical property data for 1,1,3,3,5,5,7,7-octamethyltetrasiloxane-
1,7-diol. CAS Registry Number: 3081-07-0. Available online at

https://heronet.epa.gov/heronet/index.cfm/reference/download/reference id/7991715C3 - 2976
Elsevier. (2021c). Reaxys: physical-chemical property data for dimethylsilanediol. CAS Registry
Number: 1066-42-8. Available online at

https://heronet.epa.gov/heronet/index.cfm/reference/download/reference id/7995011C3 - 2976
Elsevier. (2021d). Reaxys: physical-chemical property data for tetramethyl-l,3-disiloxanediol. CAS
Registry Number: 1118-15-6. Available online at

https://heronet.epa.gov/heronet/index.cfm/reference/download/reference id/7994661C3 - 2976
Haynes, WM, (Ed.). (2014). l,l,3,3-Tetramethyl-l,3-disiloxanediol. In CRC Handbook of Chemistry
and Physics. Boca Raton, FL: CRC Press. Taylor & Francis Group.
https://heronet.epa.gov/heronet/index.cfm/reference/download/reference id/7998725C3 -
2819,2976

NLM (National Library of Medicine). (2021a). Pubchem: 1,3-Disiloxanediol, 1,1,3,3-tetramethyl-. CAS
registry number: 1118-15-6. Available online at

https://heronet.epa.gov/heronet/index.cfm/reference/download/reference id/7997877C3 - 2976
NLM (National Library of Medicine). (2021b). Pubchem: Dimethylsilanediol. CAS registry number:
1066-42-8. Available online at

https://heronet.epa.gov/heronet/index.cfm/reference/download/reference id/7998093C3 - 2976
RSC (Royal Society of Chemistry). (2021). ChemSpider: Dimethylsilanediol. Available online at

https://heronet.epa.gov/heronet/index.cfm/reference/download/reference id/7999339C3 - 2976
(accessed April 27, 2021).

U.S. EPA (U.S. Environmental Protection Agency). (2012). Estimation Programs Interface Suite™ for
Microsoft® Windows, v 4.11 [Computer Program], Washington, DC. Retrieved from
https://www.epa.gov/tsca-screening-tools/epi-suitetm-estimation-program-interface
U.S. EPA (U.S. Environmental Protection Agency). (2021a). Chemistry dashboard information for 1,3-
Disiloxanediol, 1,1,3,3-tetramethyl-. CAS registry number: 1118-15-6. Available online at
https://heronet.epa.gov/heronet/index.cfm/reference/download/reference id/7995923C3 - 2976
U.S. EPA (U.S. Environmental Protection Agency). (2021b). Chemistry dashboard information for
Dimethylsilanediol. CAS registry number: 1066-42-8. Available online at
https://heronet.epa.gov/heronet/index.cfm/reference/download/reference id/7996867C3 - 2976
Xu. S: Kropscott B. (2012). Method for simultaneous determination of partition coefficients for cyclic
volatile methylsiloxanes and dimethylsilanediol. Anal Chem 84: 1948-1955.
https://heronet.epa.gov/heronet/index.cfm/reference/download/reference id/2188633C3 -
384,2932,2976

Page 63 of 63


-------