Alcohols, C10-12, ethoxylated

Partition coefficient

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

partition coefficient

Type of information:

mixture rules calculation

Adequacy of study:

supporting study

Study period:

2012

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Calculation from experimentally derived Koc data using an equation form the 2003 EU Technical Guidance Document on Risk Assessment Part III, Chapter 4, Section 4.3

Qualifier:

according to guideline

Guideline:

other: 2003 EU Technical Guidance Document on Risk Assessment Part III, Chapter 4, Section 4.3, p. 26

Principles of method if other than guideline:

Log Kow was calculated using an equation derived from experimentally determined Koc values for analogue structures using the 2003 TGD equation for predominantly hydrophobic substances.

GLP compliance:

no

Type of method:

other: calculation from log Koc values

Partition coefficient type:

octanol-water

Type:

log Pow

Partition coefficient:

3.9

Remarks on result:

other: weight-averaged value

Details on results:

Weight-averaged log Koc of the whole substance based on normalized composition: 3.26.
This value was used in the rearranged TDG equation mentioned above resulting in a log Pow value of 3.90.

Reference 2

Endpoint:

partition coefficient

Type of information:

mixture rules calculation

Adequacy of study:

supporting study

Study period:

2012

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

accepted calculation method

Justification for type of information:

QSAR prediction (KOWWIN v1.68)

Principles of method if other than guideline:

The calculations were performed for the linear free alcohols and ethoxylated alcohols (AE) with ethoxylation degree of 1 and 3, respectively, using KOWWIN v1.68, Estimation Programs Interface Suite™ for Microsoft® Windows v4.10. US EPA, United States Environmental Protection Agency, Washington, DC, USA.
In order to derive a single value for risk assessment, the various calculated Log Pow values were weight-averaged using normalized values for composition (free alcohols, C10 AE and C12 AE).

GLP compliance:

no

Type of method:

other: QSAR

Partition coefficient type:

octanol-water

Type:

log Pow

Partition coefficient:

3.54

Remarks on result:

other: weight-averaged value

QSAR result; pH and temperature are not reported. For detailed description of the model and its applicability, see "Any other information on materials and methods incl. tables".

Individual calculated values for log Pow (taken from the EPIsuite v 4.10 report, 2012)

	KOWWIN log Pow calc.
Alcohol, C10	3.79
Alcohol, C12	4.77
Alcohol ethoxylate, C10, 1 EO	3.51
Alcohol ethoxylate, C12, 1 EO	4.5
Alcohol ethoxylate, C10, 3 EO	2.96
Alcohol ethoxylate, C12, 3 EO	3.95

 

Mean calculated values for log Pow for each ‘sub’-group

	Mean log Pow calc.
Free alcohols (avg of C10 and C12)	4.28
C10-EO (avg of 1EO and 3EO)	3.24
C12-EO (avg of 1EO and 3EO)	4.23

 

Result:

Weight-averaged log Pow of the whole substance based on normalized composition: 3.54

Reference 3

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12 June-5 July 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 123 (Partition Coefficient (1-Octanol / Water), Slow-Stirring Method)

GLP compliance:

no

Type of method:

slow-stirring method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Type:

Pow

Partition coefficient:

1 368

Temp.:

25 °C

Remarks on result:

other: pH of water phase after 46 h of stirring: ca 6

Type:

log Pow

Partition coefficient:

3.14

Temp.:

25 °C

Remarks on result:

other: pH of water phase after 46 h of stirring: ca 6

Details on results:

The pH of the three water phases after 46 h of stirring was ca. 6 (6.05, 6.03 and 5.98).

The concentration of the test item in the water and 1 -octanol phase was determined after 40, 42, 44 and 46 hours, ensuring that an equilibrium concentration was established in both phases. At each test time, the three different test solutions were analyzed.

The reported results refer to the mean concentrations determined in the three test solutions after 40, 42, 44 and 46 hours:

Test solution	Test item in octanol phase (mg/g)	Test item in aqueous phase (mg/g)	Pow	Average Pow	Log Pow	Average log Pow
1	32.23	0.0243	1327.9	1368	3.12	3.14
2	32.90	0.0234	1403.8		3.15
3	32.62	0.0238	1372.2		3.14

The mass balance of substance was checked by comparing the initially weighed sample with the measured concnetrations in the octanol and water phases. The following recovery values are reported:

test solution 1: 97.7%

test solution 2: 100.1%

test solution 3: 98.6%

The following partition coefficient of the test item was determined according to OECD Guideline for the Testing of Chemicals No. 123 (Slow-Stirring method):

Pow = 1368 (RSD 2.8%)

Log Pow = 3.14 (RSD 0.49%)

Description of key information

log Pow - experimental value (slow-stirring method - OECD 123): 3.14

supporting values:
log Pow - calculated using EPIsuite v 4.10 (weight-averaged value): 3.54
log Pow - calculated from weight-averaged log Koc value: 3.90

Key value for chemical safety assessment

Log Kow (Log Pow):

3.14

at the temperature of:

25 °C

Additional information

The key value for chemical safety assessment is derived from the experimentally determined log Pow value (slow-stirring method - OECD 123). In addition, the log Pow values were calculated as supporting. Two types of calculations were applied:

1. based on weight-averaged log Koc values using the TGD equation for predominantly hydrophobic substances: log Koc = 0.81 log Pow + 0.10 thus log Pow = (log Koc – 0.10)/0.81) (2003 EU Technical Guidance Document on Risk Assessment Part III, Chapter 4, Section 4.3 (pp 24 – 27)

2. based on EPIsuite v 4.10, KOWWIN v 1.68 log Pow values for (possible) individual constituents of the substance; a weighting based on normalized composition was applied to derive a log Pow value for the whole substance.