Nickel, 5-[2-(2-hydroxy-3,7-disulfo-1-naphthalenyl)diazenyl]-1H-1,2,4-triazole-3-carboxylate sodium complexes

Adsorption / desorption

Administrative data

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Study test phase 2002-10-22 to 2002-10-25. Report sign off 2002-11-14

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Meets the criteria for classification as Reliable without restriction according to Klimisch et al (1997)

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))

Deviations:

no

GLP compliance:

yes

Type of method:

HPLC estimation method

Media:

other: HPLC

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

443-510-2

EC Name:

-

Cas Number:

738587-10-5

Molecular formula:

C26H14N10Ni2O18S4 as free acid

IUPAC Name:

dinickel(2+) sodium 3-carboxy-5-[(1E)-2-(7-oxido-2,6-disulfonaphthalen-1-yl)diazen-1-yl]-1H-1,2,4-triazol-1-ide 3-carboxy-5-[(1E)-2-(7-oxido-2-sulfo-6-sulfonatonaphthalen-1-yl)diazen-1-yl]-1H-1,2,4-triazol-1-ide

Radiolabelling:

no

Study design

Test temperature:

20.1 - 22.3 deg C

HPLC method

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: A HPLC system comprising of the following components - HPLC pump, 25cm x 4.6mm id column packed with a 5um CN phase, Photo Diode Array (PDA) detector, Chromotography data system.
- Injection volume: 100ul

MOBILE PHASES
- Type: 55% methanol and 45% pH adjusted deionised water pumped at a flow rate of 1.5 ml/min

DETERMINATION OF DEAD TIME
- Method: by inert substances which are not retained by the column (sodium nitrate)

REFERENCE SUBSTANCES
- Identity: Acetamilide, Atrazin, Isoproturon, Linuron, Naphthalene, 1,2,3-Trichlorobenzene, Fenthion, Phenanthrene, ppDDT.

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column:100ul
- Quantity of reference substances:100ul

REPETITIONS
- Number of determinations: Reference substances were injected in duplicate as a minimum and average retention times determined. This was performed as least once daily.

EVALUATION
- Calculation of capacity factors k': k' = (retention time of test substance - column dead time)/ column dead time
- Calculation of retention times: measured by HPLC
- Determination of the log Koc value: Determined from equation of the line from the calibration graph of logKoc versus logk'

Batch equilibrium or other method

Analytical monitoring:

no

Results and discussion

Adsorption coefficient

Adsorption coefficient 1

Type:

log Koc

Remarks:

Estimated

Value:

> 5

Remarks on result:

other: pH2

Adsorption coefficient 2

Type:

log Koc

Remarks:

Estimated

Value:

> 5

Remarks on result:

other: pH10

Results: HPLC method

Details on results (HPLC method):

- Retention times (s) of reference substances used for calibration:
pH2
Sodium nitrate 91 (this is the t0 value)
Acetamilide 137
Atrazin 147
Isoproturon 158
Linuron 162
Naphthalene 183
1,2,3-Trichlorobenzene 174
Fenthion 190
Phenanthrene 232

pH10
Sodium nitrate 83 (this is the t0 value)
Acetamilide 135
Atrazin 138
Isoproturon 153
Linuron 156
Naphthalene 175
1,2,3-Trichlorobenzene 167
Fenthion 180
Phenanthrene 218

- Details of fitted regression line (log k' vs. log Koc): pH2 y = 5.857x + 3.018 r2 = 0.928, pH10 y=7.704x + 2.844 r2=0.932

- Average retention data (s) for test substance: pH2 >900, pH10 71

Any other information on results incl. tables

At pH 2 the log Koc is >5.0 and at pH 10 the log Koc is <1.5.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The test method has been validated for the quantitative estimation of logKoc values in the range 1.5 to 5.0. In those instances where the statistical treatment of the experimental data produces a calculated log Koc value outside of this range then the final result is quoted as either <1.5 or >5.0 as appropriate. At pH 2 the logk' for the test substance was >0.949 therefore the estimated logKoc for the test substance is >5.0. At pH 10 it was not possible to calculate the logk' for the test substance therefore the estimated log Koc for the test substance is <1.5.

Executive summary:

Introduction

This study was undertaken to determine the adsorption coeffiecient (Koc) of the test substance using a high peformance liquid chromatography (HPLC) correlation technique. The method was designed to be compatible with the following

- OECD Guideline for the Tesing of Chemicals (2001).Test Guideline 121, Estimation of the Adsorption Coefficient (Koc) on Soil and Sewage Sludge using High Performanec Liquid Chromatography (HPLC). (22 January 2001).

Results & Conclusions

At pH 2 the logk' for the test substance was >0.949 therefore the estimated logKoc for the test substance is >5.0. At pH 10 it was not possible to calculate the logk' for the test substance therefore the estimated log Koc for the test substance is <1.5.