Reaction mass of 2-[[4-[[3,5-dimethyl-4-(oxiran-2-ylmethoxy)phenyl]methyl]-2,6-dimethyl-phenoxy]methyl]oxirane and 1,3-bis[4-[[3,5-dimethyl-4-(oxiran-2-ylmethoxy)phenyl]methyl]-2,6-dimethyl-phenoxy]propan-2-ol and 1-[4-[[3,5-dimethyl-4-(oxiran-2-ylmethoxy)phenyl]methyl]-2,6-dimethyl-phenoxy]-3-[4-[[4-[3-[4-[[3,5-dimethyl-4-(oxiran-2-ylmethoxy)phenyl]methyl]-2,6-dimethyl-phenoxy]-2-hydroxy-propoxy]-3,5-dimethyl-phenyl]methyl]-2,6-dimethyl-phenoxy]propan-2-ol

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.19 (Estimation of the Adsorption Coefficient (KOC) on Soil and Sewage Sludge Using High Performance Liquid Chromatography (HPLC))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Media:

other: HPLC method; representative of sorption behaviour of the test substance on soil

Radiolabelling:

no

Test temperature:

Column temperature was 25°C

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: Agilent 1200 Series Liquid Chromatograph with Chemstation software
- Column: HyperClone CN (CPS) (25 cm x 4.6 mm internal diameter)
- Flow rate: 1.0 mL/Minute
- Injection volume: 10 μL
- Detection system: UV set at 210 nm

MOBILE PHASES
- Type: Mobile phase A (Methanol: water (55:45 v/v), Mobile phase B (Methanol).

DETERMINATION OF DEAD TIME
- Method: An internal standard (formamide) with no retention on the HPLC column was used to determine the dead time of the HPLC system.

REFERENCE SUBSTANCES
- Identity: Internal dead time standard (formamide), Acetanilide, Nitrobenzene, Naphthalene, 2-Methylnaphthalene, Anthracene and DDT with known LogKoc values.

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: 10 μL (approximately 90 mg/L in mobile phase A).
- Quantity of reference substances: 10 μL at varying appropriate concentrations (3-200 mg/L).

REPETITIONS
- Number of determinations: Duplicate

EVALUATION
- Calculation of capacity factors k':
K = ((measured retention time of sample or reference)-(the retention time of the internal deadtime standard))/the retention time of the internal deadtime standard.

- Determination of the log Koc value: A calibration plot of Log10k vs Log10Koc was conducted for reference standards. The logarithm of the capacity factors for the test substance was then calculated and the log10Koc value determined by interpolation.

Type:

log Koc

Value:

ca. 4.3

Temp.:

25 °C

Remarks on result:

other: Major chromatographic component

Type:

log Koc

Value:

> 5.6

Temp.:

25 °C

Remarks on result:

other: Significant components noted after retention time of highest available standard

Details on results (HPLC method):

- Retention times of reference substances used for calibration: Various (3.551 to 24.292 minutes)
- Details of fitted regression line (log k' vs. log Koc): Linear regression (based on mean of standard runs A and B): log10Koc = 2.88 log10k + 3.28
- Average retention data for test substance: The duplicate retention time values were 9.572 and 9.573 minutes.

Validity criteria fulfilled:

yes

Conclusions:

The test substance was determined to have a log10Koc value of 4.3 (equivalent Koc = 19000). The determined value was for the major chromatographic component. Other significant components were noted after the retention time of the highest available reference standard, DDT, indicating log10Koc values in excess of 5.6 for these.

Description of key information

A study is available assessing the adsorption coefficient of the test substance by the HPLC method according to the OECD guideline 121.

Key value for chemical safety assessment

Koc at 20 °C:

19 000

Additional information

The major chromatographic component of the test substance provided a LogKoc value of 4.3 (Koc of 19,000). Other significant components were noted to have LogKoc values > 5.6. All components showed high potential for adsorption to soil (low mobility) in this screening test; the Koc value for the major component has been used in the CSA as representative for registerable substance.

Other adsorption coefficient indicated as dimensionless:
- other: Log Koc (other significant components) ,5.6 at the temperature 25.0°C
- other: Koc (other significant components) ,398107.0 at the temperature 25.0°C

Further information on adsorption/desorption would not be gained from performance of additional testing as indicated in the results of the study required under Annex VIII.

[LogKoc: 4.3]