2,3-Epoxypropyl neodecanoate, oligomeric reaction products with cyclohexane-1,2-dicarboxylic anhydride and propylidenetrimethanol

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18 Sept 2017 - 03 Oct 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 121 (Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC))

Deviations:

no

Principles of method if other than guideline:

The principle of the test method is similar to that of the OECD guideline no. 117: "Partition coefficient (n-octanol/water), high performance liquid chromatography (HPLC) method". While passing through the column along with the mobile phase the test item interacts with the stationary phase. As a result of partitioning between mobile and stationary phases, the test item is retarded. The dual composition of a cyanopropyl stationary phase, having polar and non-polar sites allows for interaction of polar and non-polar groups of a molecule in a similar way as is the case for organic matter in soil or sewage sludge matrices. This enables the
relationship between the retention time on the column and the Koc on organic matter to be established.

According to the guidelines, the determination of the Koc for test items that are ionized for at least 10% within pH 5.5 to 7.5 should be performed with both the ionized and non-ionized form. Therefore, the pKa values of the test item were calculated using the Perrin calculation method (pKalc 5.0, module in Pallas 3.0, CompuDrug International San Francisco, CA, USA). Based on the calculations, the determination was performed at neutral pH.

Solutions of one reference substance based on soil adsorption data and the test item were analyzed. Based on the retention times of the compounds the Koc and log Koc values of the test item were determined.

GLP compliance:

yes

Type of method:

HPLC estimation method

Radiolabelling:

no

Test temperature:

NA

Details on study design: HPLC method:

Adsorption of the test substance was measured via the HPLC method based on soil-adsorption reference data.

A gradient was applied in order to elute components with log Koc > 5.63 from the column. The reference compounds are eluted in the isocratic part of the method and the gradient step was not applied for these injections.


Preparation of Solutions

Reference Substance Solution:
Stock solutions of the reference substances at concentrations of approximately 1 g/L in methanol were used. The stock solutions were diluted to obtain an end solution of 55/45 (v/v) methanol/water.
The blank solution for the mixture of reference substances was 55/45 (v/v) methanol/water.

Test Solution:
A 1000 mg/L stock solution of the test item was prepared in methanol. The stock solution was two times 100-fold diluted with 55/45 (v/v) methanol/water. The final concentration of the test item solution was 0.1 mg/L. The test item blank solution was 55/45 (v/v) methanol/water.


Analytical details

Instrument: Acquity UPLC system (Waters, Milford, MA, USA)
Detector: Acquity UPLC TUV detector (Waters) and Acquity TQD mass spectrometer (Waters)
Column: Acquity UPLC HSS Cyano, 100 mm x 2.1 mm i.d., dp = 1.8 ¿m (Waters)
Column temperature: 35°C ± 1°C
Injection volume: 5 ¿L
Solvent A: 100% water
Solvent B: 100% methanol
Gradient: (see ¿Any other information on materials and methods incl. tables¿)
Flow: 0.4 mL/min
UV detection: 210 nm
MS detection:
Ionization source: ESI+
Cone voltage: 80 V
Collision energy: 58 eV
Quantitation: m/z 1298.9 --> 229.1

Sample Injections:
Reference substance and test item solutions were injected in duplicate. Blank solutions were analysed by single injection.

Details on sampling:

NA

Details on matrix:

NA

Details on test conditions:

NA

Computational methods:

NA

Key result

Sample No.:

#1

Type:

Koc

Value:

> 430 000 L/kg

pH:

7

Sample No.:

#1

Type:

log Koc

Value:

> 5.63 L/kg

pH:

7

Details on results (HPLC method):

In the UPLC-UV chromatogram of the test item solution, one peak with a retention time of 11.231 minutes was observed. Under the same analytical conditions, the retention time of 4,4¿-DDT (log Koc = 5.63) was 5.525 minutes. It was concluded that the log Koc of test item was > 5.63 (Koc > 4.27 x 10^5).

Adsorption and desorption constants:

NA

Recovery of test material:

NA

Concentration of test substance at end of adsorption equilibration period:

NA

Concentration of test substance at end of desorption equilibration period:

NA

Transformation products:

not specified

Details on results (Batch equilibrium method):

NA

Statistics:

NA

Koc of the test item,Epoxypropyl neodecanoate, oligomeric reaction products with cyclohexane-1,2-dicarboxylic anhydride and propylidenetrimethanol

Substance	Retention time (minutes)			Log koc	Koc
	Tr,1	Tr,2	mean
4,4¿-DDT	5.509	5.541	5.525	5.63
Test item¿peak 1	11.229	11.233	11.231	>5.63	>4.3 x 10^5

 

Validity criteria fulfilled:

yes

Conclusions:

The Koc and log Koc value of the test item at neutral pH was >4.3 x 10^5 and >5.63, respectively.

Executive summary:

The HPLC method using soil-adsorption-reference data was applied for the determination of the adsorption coefficient (Koc) of Epoxypropyl neodecanoate, oligomeric reaction products with cyclohexane-1,2-dicarboxylic anhydride and propylidenetrimethanol. The Koc and log Koc value of the test item at neutral pH was >4.3 x 10^5 and >5.63, respectively.

Description of key information

The HPLC method using soil-adsorption-reference data was applied for the determination of the adsorption coefficient (Koc) of Epoxypropyl neodecanoate, oligomeric reaction products with cyclohexane-1,2-dicarboxylic anhydride and propylidenetrimethanol. The Koc and log Koc value of the test item at neutral pH was >4.3 x 10^5 and >5.63, respectively.

Key value for chemical safety assessment

Koc at 20 °C:

430 000