.beta.-Alanine, N-[2-chloro-4-[2-(4-nitrophenyl)diazenyl]phenyl]-, 2-[2-(1,3-dihydro-1,3-dioxo-2H-isoindol-2-yl)ethoxy]-2-oxoethyl ester

Adsorption / desorption

Administrative data

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From December 13 to December 17, 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Test guideline 1

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))

Test guideline 2

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))

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Media:

soil/sewage sludge

Test material

Test material information

Constituent 1

Reference substance name:

Yellow 981

IUPAC Name:

Yellow 981

Test material form:

solid: particulate/powder

Study design

Test temperature:

25 °C

HPLC method

Details on study design: HPLC method:

The first test to determine the adsorption coefficient (Koc) of test item was performed with methanol as organic solvent. Methanol was not sufficient to elute the test item from the column. Referring to this, acetonitrile was used as organic solvent.
Column: LiChrospher 100 CN, part. size 5 pm, 250 mm × 4 mm
Mobile phase: water and acetonitrile (45:55; v/v); pH 6.7
Detection: 210 nm for the reference items and for sodium nitrate; 438 nm for the test item solution
Temperature: 25 °C
lnjection volume: 5 µl
Flow: 1.0 ml/min

Batch equilibrium or other method

Details on test conditions:

Performance of the test
Test item (9 mg) was dissolved in DMF (10 ml) to prepare a stock solution of 900 µg/ml.
The stock soluition (1 ml) was diluted with acetonitrile to 10 ml to obtain a standard solution of 90 µg/ml. The pH value of the test item solution was determined to be 6.6. The test item solution was injected three times.

Reference Solutions
Stock solutions of the reference items in acetonitrile were prepared using as reference items: phenol, isoproturon and linuron, pyrazophos and diclofop-methyl, each dissolved in 10 ml acetonitrile. 2.4-DDT was dissolved in 25 ml acetonitrile.
A combined reference solution was prepared by transferring 220 µl of the phenol stock solution, 250 µl of the isoproturon stock solution, 165 µl of the linuron stock solution, 1110 µl of the pyrazophos stock solution 250 µl of the diclofop-methyl stock solution and 400 µl of the 2.4-DDT stock solution into one volumetric flask and diluting to a volume of 10 ml with a solvent mixture of water and acetonitrile (45:55: v/v). This reference solution was injected six
times.
Sodium nitrate (25 mg) was diluted to 100 ml with acetonitrile to obtain a stock solution. The stock solution (100 µl) was diluted to 1 ml with a solvent mixture of water and acetonitrile (45:55: v/v). Thìs sodium nitrate solution was injected two times for the determination of the deadtime of the HPLC system.

Results and discussion

Adsorption coefficient

Type:

log Koc

Remarks:

(Koc = 160913)

Value:

5.2 dimensionless

Results: HPLC method

Details on results (HPLC method):

Retention times (minutes):
- Test item: 7.14
- Negative control (dead time): 1.32
- Reference items:
phenol: 3.50
isoproturon: 3.87
linuron: 4.43
pyrazophos: 5.11
diclofap-methyl: 6.04
2.4-DDT: 7.72

logKoc
- Test item: 5.2
- Negative control (dead time): -
- Reference items:
phenol: 1.32
isoproturon: 1.86
linuron: 2.59
pyrazophos: 3.65
diclofap-methyl: 4.20
2.4-DDT: 5.63

Results: Batch equilibrium or other method

Adsorption and desorption constants:

logKoc = 5.2
Koc = 160913

Details on results (Batch equilibrium method):

The logKoc value of 5.2 indicates that the substnce is immobile and remains preferably in soil.

Applicant's summary and conclusion

Conclusions:

Koc = 160913 (log Koc = 5.2), thus, the substance is immobile in soil.