2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropan-1-one

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:

2003-01-21 to 2003-01-21

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))

Version / remarks:

Adopted Test Guideline (January 2001)

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))

Version / remarks:

EC Directive 2001/59/EC, C. 19, EC publicafion L 225, August 2001

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Media:

soil

Radiolabelling:

no

Test temperature:

25 °C

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: Varian autosampler 9100; Varian pump 9010; Varian detector 9050; Jones column oven 7990
- Type: HPLC
- Type, material and dimension of analytical (guard) column: LiChrospher 100 CN, part, size 5 µm, 250 mm x 4 mm
- Detection system: UV/Vis (detection of the reference items and sodium nitrate: 210 nm; detection of the test item solution: 260 nm)

MOBILE PHASES
- Type: Water / methanol (45:55; v/v)
- pH: 6.8
- Solutes for dissolving test and reference substances: test item in THF (10 mL); reference item in methanol

DETERMINATION OF DEAD TIME
- Method: retetion time of sodium nitrate (1.146 min)


DETERMINATION OF RETENTION TIMES
- Quantity of reference substances: Acetanilide (2.980 min); isoproturon (3.541 min); triadimenol (4.101 min); pyrazophos (6.145 min); diclofop-methyl (7.487 min); 2.4-DDT (12.729 min)


REPETITIONS
- Number of determinations:3

EVALUATION
- Calculation of capacity factors k': k`=(tr(retention of test item)- to (dead-time))/to
- Determination of the log Koc value: log KOC = ( log k`- Y-axis intercept of the regression curve)/slope

Type:

log Koc

Value:

2.02

Temp.:

25 °C

Type:

Koc

Value:

104

Temp.:

25 °C

Details on results (HPLC method):

- Retention times of reference substances used for calibration: Acetanilide (2.980 min); isoproturon (3.541 min); triadimenol (4.101 min); pyrazophos (6.145 min); diclofop-methyl (7.487 min); 2.4-DDT (12.729 min)
- Details of fitted regression line (log k' vs. log Koc): log Koc = (log k`+ 0.023) + 0.182

The test Item solution was injected three times and the combined reference solution was injected six times. The log Koc was calculated using a regression curve (log k' vs. log Koc) and was found to be 2.02 which is equal to a KQC value of 104. In the present study the reference items covered the range of log Koc 1.25 to log Koc 5.63. The chromatography of the test item resulted in one main peak with a well-defined and reproducible retention time. The HPLC method was therefore considered to be suitable for the purpose of the study. Based on the chromatographic data, the test item was considered to be stable during the test procedure. The capacity factor (k') was calculated for each reference item using the retention times. Log Koc was plotted versus log k for each component to obtain a regression curve. The tabulated values may represent rounded or mean results, which were obtained by calculation using the exact raw data. In conclusion, the log of the adsorption coefficient (Koc) of the test item was estimated to be log Koc = 2.02 which is equal to Koc value of 104 using the HPLC method. This value indicates that the test item is moderately mobile.

Validity criteria fulfilled:

yes

Conclusions:

Adsorption to solid soil phase is not expected.

Executive summary:

In this guideline (OECD 121) study conducted with GLP certification, the log adsorption coefficient of the test material (EC 444-860-9) was determined to be log Koc = 2.02.

Description of key information

Significant adsorption of the test substance to solid soil phase is not expected.

The log Koc of the test substance measured in a guideline study according to OECD 121 was 2.02 (corresponding Koc = 104) , hence adsorption of the substance to soil particles is not likely (RCC Ltd., 2003).

Key value for chemical safety assessment

Koc at 20 °C:

104

Additional information

Study conducted to recognised testing guidelines with GLP certification.

[LogKoc: 2.02]