Reactionmass of octan-2-yl prop-2-enoate and octan-3-yl prop-2-enoate and octan-4-yl prop-2-enoate

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:

August 14, 2019 to August 17, 2019

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7550 (Partition Coefficient, n-octanol / H2O, Shake Flask Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Other quality assurance:

ISO/IEC 17025 (General requirements for the competence of testing and calibration laboratories)

Type of method:

flask method

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

Source and lot/batch No.of test material: 41-4205-7138-6 (R-57318), CPDC Load ID S352546
- Expiration date of the lot/batch: May 01, 2020
- Purity test date: May 01, 2018

Analytical method:

gas chromatography

mass spectrometry

Key result

Type:

log Pow

Partition coefficient:

4.8

Temp.:

23.9 °C

Remarks on result:

other: Log Kow for 2-octyl acrylate isomer, pH not measured.

Key result

Type:

log Pow

Partition coefficient:

4.7

Temp.:

23.9 °C

Remarks on result:

other: Log Kow for 3-octyl acrylate isomer, pH not measured.

Key result

Type:

log Pow

Partition coefficient:

4.7

Temp.:

23.9 °C

Remarks on result:

other: Log Kow for 4-octyl acrylate isomer, pH not measured.

Key result

Type:

Pow

Partition coefficient:

63 900

Temp.:

23.9 °C

Remarks on result:

other: Kow for 2-octyl acrylate isomer, % RSD = 17%, pH not measured.

Key result

Type:

Pow

Partition coefficient:

47 400

Temp.:

23.9 °C

Remarks on result:

other: Kow for 3-octyl acrylate isomer, % RSD = 15%, pH not measured.

Key result

Type:

Pow

Partition coefficient:

45 800

Temp.:

23.9 °C

Remarks on result:

other: Kow for 4-octyl acrylate isomer, % RSD = 17%, pH not measured.

Details on results:

MTDID 44428 is a mixture of octyl acrylate isomers, the Kow was determined for 2-octyl acrylate isomer, 3-octyl acrylate isomer, and 4-octyl acrylate isomer. The average measured Kow of 2-octyl acrylate is 63900 (RSD=17%), the average measured Kow of 3-octyl acrylate is 47400 (RSD=15%), and the average measured Kow of 4-octyl acrylate is 45800 (RSD=17%). For the individual isomers, the calculated log Kow is 4.8 for 2-octyl acrylate, 4.7 for 3-octyl acrylate, and 4.7 for 4-octyl acrylate.

Table 1. Kow results summary for MTDID 44428

Ratio	Vial	2-octyl acrylate Kow^(1)	2-octyl acrylate Log Kow^(1)	3-octyl acrylate Kow	3-octyl acrylate Log Kow	4-octyl acrylate Kow	4-octyl acrylate Log Kow
Ratio A (1:1)	1^(2)	16900^(2)	4.2^(2)	15100^(2)	4.2^(2)	14500^(2)	4.2^(2)
	2	52600	4.7	39800	4.6	37600	4.6
Ratio B (1:2)	1	54400	4.7	41200	4.6	39100	4.6
	2	62600	4.8	46700	4.7	45000	4.7
Ratio C (2:1)	1	73700	4.9	52700	4.7	51400	4.7
	2	76200	4.9	56500	4.8	55700	4.7
Average ± RSD		63900 ±17%	4.8	47400 ±15%	4.7	45800 ±17%	4.7

1. Reported results may be biased high due to low water phase LCS results. Results suggest possible instability in the water phase.

2. Vial 1 for Ratio A was determined to be an outlier per Dixon’s Q-test as described in the protocol. This value was not be used in the final calculations of the Kow and log Kow

Conclusions:

MTDID 44428 is a mixture of octyl acrylate isomers, the Kow was determined for the 2-octyl acrylate isomer, 3-octyl acrylate isomer, and 4-octyl acrylate isomer. Under the conditions of this study, the average log Kow of 2-octyl acrylate is 4.8 for 2-octyl acrylate, 4.7 for 3-octyl acrylate, and 4.7 for 4-octyl acrylate.

Executive summary:

The n-Octanol/Water Partition Coefficient (Kow) of MTDID 44428 was determined according to U.S EPA guidance document OPPTS 830.7550 "Partition Coefficient (n-Octanol/Water), Shake Flask Method".

Duplicate test vessels of three different volume ratios (1:1, 1:2, and 2:1) of MTDID 44428 dosed n-octanol to water were prepared. The samples were rotated 180 ° about their transverse axis for 100 rotations for five minutes to ensure proper mixing of the test system solvents. The samples were then centrifuged at 1000 RPM for 30 minutes to ensure a visibly clear separation of layers, prior to removing n-octanol and the aqueous sample analysis aliquots. Duplicate n-octanol aliquots were removed first from each vial and diluted with methanol. An aliquot of the methanolic solution was added through the septum seals of the analysis vials containing reagent water for analysis. After the n-octanol aliquot removal, duplicate water aliquots were carefully removed and dispel through the septum into capped analysis vials containing Milli Q water. All samples were analyzed using Purge and Trap gas chromatography/mass spectrometry (GC/MS).

MTDID 44428 is a mixture of octyl acrylate isomers. The partitioning coefficients were determined based on measured concentrations in n-octanol and water phase for 2-octyl acrylate, 3-octyl acrylate, and 4-octyl acrylate. Under the conditions of this study,  the average measured Kow of 2-octyl acrylate is 63900 (RSD=17%), the average measured Kow of 3-octyl acrylate is 47400 (RSD=15%), and the average measured Kow of 4-octyl acrylate is 45800 (RSD=17%). The calculated log Kow is 4.8 for 2-octyl acrylate, 4.7 for 3-octyl acrylate, and 4.7 for 4-octyl acrylate.

This is a guideline study and conducted under GLP. The Kow were measured for components present at >10% purity. However, the Nernst partition law applies strictly to a pure substance dispersed between two pure solvents and when the concentration of the solute in either phase is not more than 0.01 M. If several different solutes occur in one or both phases at the same time, this may affect the partition coefficient results.  Therefore, it is considered reliable with restriction and a key study. This study is pertinent to the fate of MTDID 44428 and may be used for Risk Assessment, Classification & Labelling, and PBT Analysis.

Reference 2

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

21-23 July 2014

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)

GLP compliance:

no

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

4.38

Temp.:

40 °C

Two peaks were averaged: 1.39 minutes for the Uracil retention time and 8.72 minutes for test material retention time. The log Kow was calculated to be 4.38.

	Uracil RT 1	Uracil RT 2	Uracil Average	Retention Time 1	Retention Time 2	Average Retentin Time	K	Log K	Log K - Literature	Log K - Calculated
Uracil	1.38	1.38	1.38
Methyl Myristate				33.82	33.92	33.87	23.49	1.37	6.41	6.29
Ethyl Laurate				24.18	24.15	24.16	16.47	1.22	5.71	5.84
Methyl Dodecanoate				17.96	17.98	17.97	11.99	1.08	5.41	5.43
Methyl Deconoate				9.85	9.85	9.85	6.12	0.79	4.41	4.57
Methyl Nonanate				7.42	7.42	7.42	4.37	0.64	3.87	4.14
MTDID 44428	1.39	1.39	1.39	8.71	8.73	8.72	5.29	0.72	N/A	4.38
2 -OA	1.40	1.40	1.40	8.82	8.83	8.82	5.31	0.73	N/A	4.39
3 -OA	1.39	1.38	1.38	8.54	8.54	8.54	5.17	0.71	N/A	4.35

Conclusions:

The log partition coefficient n-octanol/water of MTDID 44428 was determined to be 4.38.

Executive summary:

The n-octanol/water partition coefficient of MTDID 44428 was determined based on the correlation between the retention of the test substance on a reversed phase column and the log Kow.

For the test system, the calibration equation was established using reference substances with known log Kow of 3.87 - 6.41.  Duplicate tests were performed using 60: 40 acetonitrile : water for mobile phase. An average log Kow of 4.38 was calculated for MTDID 44428. This is supported by log Kow values of 4.39 and 4.35 for two specific constituents measured as isolated chemicals.

The study method was comparable to OECD guideline 117 but is not GLP compliant. Therefore, this study is considered reliable with acceptable restriction.

Description of key information

MTDID 44428 is a mixture of octyl acrylate isomers. The average log Kow is 4.8 for 2-octyl acrylate, 4.7 for 3-octyl acrylate, and 4.7 for 4-octyl acrylate at 23.9 °C.

Key value for chemical safety assessment

Log Kow (Log Pow):

4.7

at the temperature of:

23.9 °C

Additional information

The n-Octanol/Water Partition Coefficient (Kow) of MTDID 44428 was determined in 2019 according to U.S EPA guidance document OPPTS 830.7550 "Partition Coefficient (n-Octanol/Water), Shake Flask Method". MTDID 44428 is a mixture of octyl acrylate isomers. The partitioning coefficients were determined based on measured concentrations in n-octanol and water phase for 2-octyl acrylate, 3-octyl acrylate, and 4-octyl acrylate. The  log Kow is 4.8 for 2-octyl acrylate, 4.7 for 3-octyl acrylate, and 4.7 for 4-octyl acrylate at 23.9 °C. This is a guideline study and conducted under GLP compliance. The Kow were measured for components present at >10% purity. However, the Nernst partition law applies strictly to a pure substance dispersed between two pure solvents and when the concentration of the solute in either phase is not more than 0.01 M. If several different solutes occur in one or both phases at the same time, this may affect the partition coefficient results. Therefore, it is considered reliable with restriction and a key study. This study is pertinent to the fate of MTDID 44428 and may be used for Risk Assessment, Classification & Labelling, and PBT Analysis.

A previous study was conducted in 2014 in method comparable to OECD guideline 117. An average log Kow of 4.38 was calculated for MTDID 44428 at 40 °C. The log Kow values of 4.39 for 2-octyl acrylate and 4.35 for 3-octyl acrylate were also measured as isolated chemicals at 40 °C. This study was not GLP compliant. The reference substances used in this study have log Kow range from 3.87 – 6.41 with some structural similarities including ester groups and long alkyl chains, but do not contain the acrylate structural functionality of the test substance. Therefore, it is considered reliable with acceptable restriction, and a supporting study.