3,6,9-trioxaundecamethylene dimethacrylate

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017-04-07 to 2017-07-20

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7570 (Partition Coefficient, n-octanol / H2O, Estimation by Liquid Chromatography)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

0.431

Temp.:

40 °C

pH:

6

Remarks on result:

other: Peak #1: area = 3.98%

Key result

Type:

log Pow

Partition coefficient:

2.04

Temp.:

40 °C

pH:

6

Remarks on result:

other: Peak #2: area = 96.1%

RESULTS AND DISCUSSION

A total of seven reference substances were prepared and injected in duplicate (once at the beginning and once near the end of the HPLC sequence). The retention times for one of the reference substances, thiourea, was used to determine the analytical column dead time (t0) for use in calculating capacity factors (k) of the remaining reference substances and the test substance. The mean retention time of thiourea was 0.851 minutes.

Six additional reference substances were analyzed. The capacity factors of all the reference substances were calculated based upon their retention times. Calculated Log k values for the reference substances are presented in Table 4.

Table 4 Reference Standards Retention Times, Capacity Factors, and Log P_OWValues 

Reference Standard	Concentration (mg/L)	Retention Time (minutes)	Capacity Factor (k)^1,2	log k^2	log POW^3
Thiourea	10.0	0.852 0.849	N/A	N/A	N/A
Acetanilide	20.0	0.957 0.951	0.125 0.118	-0.902 -0.928	1.0
2-Nitrophenol	10.0	1.150 1.146	0.352 0.347	-0.453 -0.459	1.8
Toluene	50.0	1.827 1.820	1.148 1.140	0.0600 0.0569	2.7
Naphthalene	5.00	2.178 2.173	1.561 1.555	0.193 0.192	3.6
Fluoranthene	5.02	5.515 5.518	5.484 5.488	0.739 0.739	5.1
4’-DDT	50.0	9.872 9.833	10.607 10.561	1.026 1.024	6.5
^1  Capacity factor (k) is the standard retention time minus the mean column dead time (0.851 minutes for thiourea) divided by the mean column dead time. ^2  Values obtained utilizing Microsoft® Excel 2010 in full precision mode. Manual calculations may differ slightly. ^3Log POWvalues are based on literature values provided in OECD Guideline 117.

Before the initial injection of the reference standards, an injection of a reagent blank solution (75%:25% MeOH: H2O, v/v) showed that the reagents used were free of any contaminants and confirmed the peak retention assignments for the reference substances.

The three 0.100 mg a.i./mL test substance solutions were sequentially injected. The test substance eluted as two distinct peaks on the UV detector. A fourth test substance solution at 0.500 mg a.i./mL was subsequently injected to verify that the peaks were correctly attributed to the test substance. The capacity factor (k) was calculated based on the retention times and the results for the three

injections were averaged. The corresponding Log POW values were calculated to be 0.431 and 2.04, corresponding to 3.98% and 96.1% of the total peak area respectively. Peak area is determined by the absorptivity of the individual molecules and as such the peak area percent does not necessarily reflect the concentration of each molecule in the test substance. The calculated mean retention time, capacity factor, and mean n-octanol/water partition coefficient for the test substance are presented in Table 5.

Table 5 Log n-Octanol/Water Partition Coefficients (Log P_OW) Based on UV Data for the Test Substance

	Sample Number (524C-139-)		Retention Time (minutes)		Mean () Standard Deviation (SD)^1		Log POW^1,2			Mean () Standard Deviation (SD)^1,2
	1 (Peak 1) 2 (Peak 1) 3 (Peak 1)		0.949 0.951 0.952		= 0.951 SD = 0.0015		0.410 0.436 0.448			= 0.431 SD = 0.019
	1 (Peak 2) 2 (Peak 2) 3 (Peak 2)		1.207 1.209 1.209		= 1.208 SD = 0.0012		2.04 2.04 2.04			= 2.04 SD = 0.0041
^1Values obtained utilizing Microsoft® Excel 2010 in full precision mode. Manual calculations may differ slightly.

Conclusions:

CONCLUSIONS
Under the chromatographic conditions specified, the test substance eluted as two peaks. The corresponding mean n-octanol/water partition coefficient (Log POW) for the test substance was a range from 0.431 to 2.04, corresponding to 3.98% and 96.1% of the test substance peak area, respectively.

Executive summary:

Under the chromatographic conditions specified, the test substance eluted as two peaks on the ultraviolet (UV) detector. The

corresponding Log POW for the test substance was a range from 0.431 to 2.04.

Description of key information

The octanol/water partition coefficient of the test item was determined in an experimental study performed in accordance with the following test guidelines: OECD 117, OPPTS 830.7570, Official Journal of the European Communities No. L383 Method A.8: Partition Coefficient and TSCA Title 40 of the Federal Code of Regulations, Part 796, Section 1570: Partition Coefficient (n-Octanol/Water) - Estimation by Liquid Chromatography, and GLP requirements.

Two peaks corresponding to the different constituents of the test item were observed. The log Kow values obtained and their respective percentage areas were:

0.431 (3.98%)

2.04 (96.1%)

Key value for chemical safety assessment

Log Kow (Log Pow):

2.04

at the temperature of:

40 °C