methyl 2-hydroxybut-3-enoate

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:

2021-11-09 to 2021-11-09

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:

adopted January 22, 2001

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Media:

soil/sewage sludge

Radiolabelling:

no

Details on study design: HPLC method:

EQUIPMENT
- Apparatus:
- HPLC system: Hitachi LaChrom Elite
L-2000 Organizer, No.: 18E32-083
L-2130 HPLC Pump, No.: 18E17-015
L-2200 Autosampler, No.: 19E40-005
L-2350 Column Oven, No.: 1831-023
- Detector: L-2400 UV Detector, No.: 18E33-030, 200 nm
- Column: LiChrospher 100 CN 250x4 mm, 5 μm; No.: 933278
- Temperature: 25 °C
- Mobile Phase: Acetonitrile : Water = 30 : 70 (v/v)
- Flow Rate: 1 mL/min
- Injection volume: 20 μL


REFERENCE SUBSTANCES
- Identity: Sodium nitrate (CAS no. 7631-99-4), Acetanilide (CAS no. 103-84-4), Pheneol (CAS no. 108-95-2), Methylbenzoate (CAS no. 93-58-3), Atrazine (CAS no. 1912-24-9), Naphthalene (CAS no. 91-20-3), Fenthion (CAS no. 55-38-9)

TEST SOLUTIONS
The reference items were dissolved in Acetonitrile. The concentrations of the stock solutions were about 1 mg/mL. These stock solutions were diluted with eluent resulting in concentrations of approximately 10 μg/mL. The test item was dissolved in Acetonitrile at ca. 1 mg/mL concentration level and was diluted with the mobile phase resulting in a 10 μg/mL solution for the measurements.

PERFORMANCE OF THE TEST
Three series of the above reference solutions were measured. Three samples of the test item solution were measured. The retention times were determined. The three calibration series and three test item samples were measured alternately. For the determination of t0 (t0 = retention time of the unretarded component) three samples of Sodium nitrate solution were injected.

EVALUATION
The capacity factors, k were calculated from the retention times (tR) of the selected reference
items and the dead time (t0): k = (tr-t0)/t0

Then the log k data of the reference items 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

Sample No.:

#1

Type:

log Koc

Value:

0.75 dimensionless

Matrix:

soil/sewage/water

Remarks on result:

other: measured using HPLC method; value extrapolated

Key result

Sample No.:

#1

Phase system:

other: soil/sewage/water

Type:

log Kp

Value:

0.75 dimensionless

Remarks on result:

other: measured using HPLC method

Details on results (HPLC method):

- Retention times of reference substances used for calibration: see attached table
- Details of fitted regression line (log k' vs. log Koc): see attached table
- Graph of regression line attached
- Average retention data for test substance: see attached table

Transformation products:

not measured

Validity criteria fulfilled:

yes

Conclusions:

Using the HPLC method according to OECD TG 121 the log Koc of the test item was determined to be < 1.25. Its extrapolated log Koc is 0.75 (corresponding to a Koc of 6).

Executive summary:

The adsorption coefficient (Koc) of the test item was determined using high performance liquid chromatography (HPLC-UV) in accordance with OECD TG 121. Detection was done at 200 nm. Values of log Koc derived from individual measurements fell within a range of 0.25 log units. The correlation coefficient R for the relationship between log k and log Koc for the set of reference items was 1.00. Difference of the estimated adsorption coefficient to the literature value of reference items was within a range of ± 0.5 log units. Therefore, all quality criteria were met. The mean retention time of 3.01 min determined for the test item based on three measurements is lower than the retention time of the first eluting standard: Acetanilide (mean 3.98 min) with a log Koc of 1.25. This result shows that the log Koc of the test item is lower than the calibrated range. The log Koc of of the test item was determined to be < 1.25. Its extrapolated log Koc is 0.75.

Description of key information

Using the HPLC method according to OECD TG 121 the log Koc of the test item was determined to be < 1.25. Its extrapolated log Koc is 0.75 (corresponding to a Koc of 6).

Key value for chemical safety assessment

Koc at 20 °C:

6

Additional information

The adsorption coefficient (Koc) of the test item was determined using high performance liquid chromatography (HPLC-UV) in accordance with OECD TG 121. Detection was done at 200 nm. Values of log Koc derived from individual measurements fell within a range of 0.25 log units. The correlation coefficient R for the relationship between log k and log Koc for the set of reference items was 1.00. Difference of the estimated adsorption coefficient to the literature value of reference items was within a range of ± 0.5 log units. Therefore, all quality criteria were met. The mean retention time of 3.01 min determined for the test item based on three measurements is lower than the retention time of the first eluting standard: Acetanilide (mean 3.98 min) with a log Koc of 1.25. This result shows that the log Koc of the test item is lower than the calibrated range. The log Koc of of the test item was determined to be < 1.25. Its extrapolated log Koc is 0.75.