Di-tert-butyl 1,1,4,4-tetramethylbut-2-yn-1,4-ylene diperoxide

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:

from 2015-05-20 to 2015-06-18

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

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))

Version / remarks:

(May 2008)

Deviations:

no

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))

Version / remarks:

(January 2001)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Media:

other: HPLC screening

Radiolabelling:

no

Test temperature:

25 °C

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: HPLC system: LaChrom Elite

- HPLC Conditions: Column: LiChrospher 100 CN (5µm) 250x4, No: 933278
Mobile Phase: Acetonitrile : Water = 55 : 45 (v/v)
Flow: 0.8 mL/min
Injection volume: 5 µL
Temperature: 25 °C
Detector: 230 nm (Reference standards)
Detector: 205 nm (DYBP-85-WO)

REFERENCE SUBSTANCES
- Identity: Sodium nitrate, Acetanilide, Methyl benzoate, Isoproturon, Linuron, Naphthalene, Pyrazophos, Phenantrene, DDT

DETERMINATION OF RETENTION TIMES
Three series of the above-mentioned reference solutions were measured with two parallel injections, each. Three series of the test item solution (in acetonitrile and in eluent) were measured with two parallel injections in booth, each. The retention times were determined. The three calibration series and three test item series were measured alternately. For the determination of t0 (t0 = retention time of the unretarded component) three series of Sodium Nitrate solution were injected two times.

EVALUATION
Chromatograms were evaluated using EZChrom Elite chromatogram processor software. Calculations were carried out using Microsoft Office Excel.
The capacity factors, k were calculated from the retention times (tR) of the selected reference substances and the dead time (t0): k = (tR-t0)/t0
Then the log k data of the reference substances were plotted against their log Koc values. The regression coefficients (a, b) were determined by linear regression calculation using the least squares method.
The log Koc value of the test item was calculated, using these regression coefficients and the capacity factor of the test item: log k = a + b*log Koc; where: Koc = adsorption coefficient; a = constant, b = slope; k = capacity factor

Key result

Type:

log Koc

Value:

4.06

Temp.:

25 °C

Remarks on result:

other: 95 % confidence interval: 0.012

Key result

Type:

Koc

Value:

11 474

Temp.:

25 °C

Remarks on result:

other: 95 % confidence interval: 276

Validity criteria fulfilled:

yes

Conclusions:

The adsorption coefficient Koc was estimated to be 11474 ± 276 (95 % confidence interval) and the log Koc was 4.06 ± 0.012 (95 % confidence interval).

Executive summary:

The purpose of the study was to estimate the adsorption coefficient, Koc of the test item using HPLC according to OECD 121 and EU Methof A.19. This method is applicable for substances, which have log Koc value ranging from 1.5 to 5.0. The adsorption coefficient Koc was estimated to be 11474 ± 276 (95 % confidence interval) and the log Koc was 4.06 ± 0.012 (95 % confidence interval).

Description of key information

The adsorption coefficient Koc was estimated to be 11474 ± 276 (95 % confidence interval) and the logKoc was 4.06 ± 0.012 (95 % confidence interval).

Key value for chemical safety assessment

Koc at 20 °C:

11 474

Additional information

The adsorption coefficient of the test substance was estimated on soil and on sewage sludge using High Performance Liquid Chromatography (HPLC). The test was conducted in accordance with the OECD guideline 121 and EU method C. 19. This method is applicable for substances, which have log Koc value ranging from 1.5 to 5.0. The adsorption coefficient Koc was estimated to be 11474 ± 276 (95 % confidence interval) and the log Koc was 4.06 ± 0.012 (95 % confidence interval).