Tetrasodium 2,2''-diamino-8,8''-dihydroxy-4',4'''-{4-[bis(2-hydroxyethyl)amino]-1,3,5-triazine-2,6-diyldiimino}bis(naphthalene-1-azobenzene-2',6-disulfonate)

Adsorption / desorption

Administrative data

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Οctober 14th, 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Report date:

2002

Materials and methods

Test guideline

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))

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:

Red LF 6339

IUPAC Name:

Red LF 6339

Radiolabelling:

no

Study design

HPLC method

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: HPLC
- Type, material and dimension of analytical (guard) column: Lichrospher 100 CN, part size 5 μm, 250 mm - 4 mm
- Detection system: UV-Vis. 210 nm for reference item and sodium nitrate. 26 nm for test item solution

MOBILE PHASES
- Type: water and methanol (45:55)
- pH: 7.8

DETERMINATION OF DEAD TIME
- Method: by means of homologous series / by inert substances which are not retained by the column

REFERENCE SUBSTANCES
- Identity: acetanilide, isoproturon, triadimenol, linuron, napthalene, pyrazophos, sodium nitrate

EVALUATION
- Calculation of capacity factors k': calculated from the retention times.
- Determination of the log Koc value: the log k' value of the test item was used to calculate its logKoc value.

Results and discussion

Adsorption coefficient

Type:

log Koc

Value:

< 1.25 dimensionless

pH:

7.8

Temp.:

25 °C

Remarks on result:

other: pH and temperature of the HPLC analysis

Applicant's summary and conclusion

Validity criteria fulfilled:

not specified

Conclusions:

log Koc < 1.25; to Koc < 18.

Executive summary:

The determination of the adsorption coefficient (Koc) of the substance was performed according to the OECD Guideline for the Testing of Chemicals, No. 121 and the EC Directive 2001/59, C.19.

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) andwas found to be < 1.25 which is equal to a Koc value of < 18. In the present study, the

reference items covered the range log Koc 1.25 to log Koc 3.65.

The retention time of the substance in the HPLC chromatogram is shorter than the dead-time.

log Koc < 1.25 which is equal to Koc < 18

The substance will not be absorbed by organic carbon in soil. The substance is very mobile.