2-Propenoic acid, methyl ester, reaction products with 2-ethyl-1-hexanamine and sodium hydroxide

Partition coefficient

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2013-02-11

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Determination has been run according to standardized method but without GLP compliance.

Principles of method if other than guideline:

The partition coefficient has been determined by dividing the octanol solubility by the aqueous solubility. The logarithm of this value is called the Log POW.

GLP compliance:

no

Type of method:

other: The partition coefficient has been determined by dividing the octanol solubility by the aqueous solubility. The logarithm of this value is called the Log POW.

Partition coefficient type:

octanol-water

Type:

log Pow

Partition coefficient:

ca. -1.5

Temp.:

20 °C

pH:

ca. 7

Details on results:

The octanol solubility is determined to 27 g/L mixture. The aqueous solubility is determined to 760 g/L mixture.
Log POW = Log Octanol solubility (27 g/L) / Water solubility (760 g/L) = Log 0.0355 = -1.45

Conclusions:

The Log POW of the substance is determined to -1.5.

Executive summary:

The Log POW of the substance is determined to -1.5.

Reference 2

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - Shake Flask Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

estimation method (solubility ratio)

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

- Composition of test material: Sodium-2-ethylhexyliminomonopropionate and Sodium-2-ethylhexyliminodipropionate
- Analytical purity: >=98%
- Purity test date: 13 December 2017
- Lot/batch No.: WI6K21X06-FD2
- Expiration date of the lot/batch: 05 December 2018
- Appearance: White paste
- Storage: At room temperature

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

<= -1.5

Temp.:

20 °C

Remarks on result:

other: pH value not reported

Preliminary Test

> Results based on the response of Sodium-2-Ethylhexyliminopropionate (m/z 202.1)

The content of test item dissolved in the n-octanol sample was 155 g/L.

> Results based on the response of Sodium-2-Ethylhexyliminodipropionate (m/z 274.2)

The content of test item dissolved in the n-octanol sample was 24.4 g/L.

Main Study

> Results based on the response of Sodium-2-Ethylhexyliminopropionate (m/z 202.1)

The results for the samples taken at 24, 48 and 72 hours are given in the table below. The solubility is reported as greater than or equal to since the solutions were not saturated 5 times due to the nature of test item (gel is formed). The maximum difference of the concentrations determined in the 24, 48 and 72 hour test samples was ≤ 15%. Based on this, the n-octanol solubility of the test item is given as the mean value of the analyzed concentrations.

Stirring time [hours]	Analyzed concentrations^1 [g/L]	Mean [g/L]	Maximum difference [%]
24 48 72	≥ 1037 ≥ 1210 ≥ 1073	≥ 1107	15

¹ n-Octanol solubility of the test item extrapolated from response for m/z 202.1

> Results based on the response of Sodium-2-Ethylhexyliminodipropionate (m/z 274.2)

The results for the samples taken at 24, 48 and 72 hours are given in the table below. The maximum difference of the concentrations determined in the 24, 48 and 72 hour test samples was ≤ 15%. Based on this, the n-octanol solubility of the test item is given as the mean value of the analyzed concentrations.

Stirring time [hours]	Analyzed concentrations^2 [g/L]	Mean [g/L]	Maximum difference [%]
24 48 72	20.4 22.8 22.6	21.9	11

² n-Octanol solubility of the test item extrapolated from response for m/z 274.2

Overall Results

Based on the response (i.e. peak area) of Sodium-2-Ethylhexyliminopropionate (m/z 202.1), the octanol solubility of the test item as a whole is calculated to be ≥ 1107 g/L. Based on the response of Sodium-2-Ethylhexyliminodipropionate (m/z 274.2), the octanol solubility of the test item as a whole is calculated to be 21.9 g/L. Depending on the peak used for calculations (m/z 202.1 or m/z 274.2), the calculated octanol solubility values for the test item are not consistent, indicating that the limit of solubility was reached for one of the two constituents, namely Sodium-2-Ethylhexyliminodipropionate (m/z 274.2).

The n-octanol solubility of the test item at 20°C shall be based on the response of its less soluble constituent, and thus reported as being equal to 21.9 g/L. According to the composition of the test item, it can be deduced that the n-octanol solubility of Sodium-2-Ethylhexyliminopropionate (m/z 202.1) at 20°C is ≥ 755 g/L (based on analytical composition) while the n-octanol solubility of Sodium-2-Ethylhexyliminodipropionate (m/z 274.2) at 20°C is 6.77 g/L (based on analytical composition).

The water solubility of the test item at 20°C is ≥ 629 g/L. The Pow of the test item, calculated upon request of the Sponsor as the quotient of the n-octanol and water solubility, was determined to be ≤ 3.4 x 10-2 which corresponds to a log Pow value of ≤ -1.5.

Conclusions:

The estimation method was applied for the determination of the partition coefficient (Pow) of the test item. The Pow value was ≤ 0.034 at 20°C. It corresponds with a log Pow value of ≤ -1.5.

Executive summary:

The n-octanol/water partition coefficient log10 Pow of the test item was determined in a GLP-compliant study performed in accordance with EU Method A.8 method and OECD Guideline No. 107, using the estimation method. The n-octanol/water partition coefficient log10 Pow of the test item was found to be ≤ -1.5 based on analytical measurements performed on its main constituents (Sodium-2-ethylhexyliminomonopropionate and Sodium-2-ethylhexyliminodipropionate).

Description of key information

The n-octanol/water partition coefficient log10 Pow of 2-Propenoic acid, methyl ester, reaction products with 2-ethyl-1-hexanamine and sodium hydroxide (methanol free) was determined in a GLP-compliant study performed in accordance with EU Method A.8 method and OECD Guideline No. 107, using the estimation method. The n-octanol/water partition coefficient log10 Pow of the test item was found to be ≤ -1.5 based on analytical measurements performed on its main constituents (Sodium-2-ethylhexyliminomonopropionate and Sodium-2-ethylhexyliminodipropionate).

Although the Critical Micelle Concentration should be preferred over the solubility in water when using the estimation method for surface active test materials, it was not used here as:

(i) the test item is composed of two main constituents exhibiting different solubility values in n-octanol;

(ii) it was not possible to obtain individual measurements of the CMC for each of the constituent.

As it was however possible to individually measure the water solubility of each of the constituent, the Pow of the test item was assessed based on the quotient of the n-octanol solubility and the water solubility of Sodium-2-ethylhexyliminomonopropionate and Sodium-2-ethylhexyliminodipropionate, respectively.

Key value for chemical safety assessment

Log Kow (Log Pow):

-1.5

at the temperature of:

20 °C

Additional information

The n-octanol/water partition coefficient log10 Pow of 2-Propenoic acid, methyl ester, reaction products with 2-ethyl-1-hexanamine and sodium hydroxide (methanol free) was determined in a GLP-compliant study performed in accordance with standard methods, without deviations. The study is considered as reliable (Klimisch 1) and is selected as a key study for the endpoint.