Trisodium 5-[[4-chloro-6-(ethylphenylamino)-1,3,5-triazin-2-yl]amino]-4-hydroxy-3-[(4-methyl-2-sulphonatophenyl)azo]naphthalene-2,7-disulphonate

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:

February 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to 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))

Deviations:

yes

Remarks:

full test not performed

GLP compliance:

no

Remarks:

only non-GLP preliminary investigations conducted

Type of method:

HPLC estimation method

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: at dry and dark place between 5-30 degC
- Stability under test conditions: stable
- Solubility and stability of the test substance in the solvent/vehicle: >200 g/L in water

Radiolabelling:

no

Test temperature:

20-25 degC (adjusted to 22 degC, not controlled)

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: HPLC Agilent 1100
- Type: HPLC-DAD system
- Type, material and dimension of analytical (guard) column: YMC-Pack CN, 250 x 4.0 mm, S-5 um, 12 nm (YMC Europe GmbH)
- Detection system: Diode Array Detection (210 nm for reference substances, 548 nm for test item)

MOBILE PHASES
- Type: Methanol : HPLC water (70:30 v/v)

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

REFERENCE SUBSTANCES
- Identity: acetanilide, monuron, phenanthrene, and 4,4'-DDT

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: 800 ng
- Quantity of reference substances: 200 ng

REPETITIONS
- Number of determinations: single replicate with double injection

Key result

Type:

log Koc

Value:

< 1.26

Temp.:

22 °C

Matrix:

soil

Remarks on result:

not determinable because of methodological limitations

Key result

Type:

log Koc

Value:

< 1.52

Temp.:

22 °C

Matrix:

sludge

Remarks on result:

not determinable because of methodological limitations

Details on results (HPLC method):

- Retention times of reference substances used for calibration:
sodium nitrate 1.392 min
acetanilide 2.911 min
monuron 3.177 min
phenanthrene 4.635 min
4,4'-DDT 6.306 min

- Average retention data for test substance:
test item 1.273 min

Validity criteria fulfilled:

not applicable

Remarks:

full study not conducted

Conclusions:

As the retention time of the test item is below that of the void time marker, the estimation of the adsorption coefficient on soil and sewage sludge according to OECD 121 is not applicable for this substance.
It may be assumed that the adsorption coefficients of the test item are below that of the reference item acetanilide (logKoc, soil < 1.26 and log Koc, sludge < 1.52).

Executive summary:

Preliminary investigations (non-GLP) for the determination of the adsorption coefficient Koc of Reactive Red 45:1 on soil and on sewage sludge using high performance liquid chromatography (HPLC) were performed according to OECD 121 and Council Regulation (EC) No.440/2008, Method C.19.

 

The results of these experiments showed that this guideline is not applicable for the determination of the adsorption coefficient (Koc) of Reactive Red 45:1 on soil and on sewage sludge because the test item has a much lower capacity factor (retention time) than even the void time marker sodium nitrate.

 

It may be assumed that the adsorption coefficients of the test item are below that of the reference item acetanilide (log K_{OC, Soil}< 1.26 log K_{OC, sludge}< 1.52).

 

Description of key information

As the retention time of the test item Reactive Red 45:1 is below that of the void time marker, the estimation of the adsorption coefficient on soil and sewage sludge according to OECD 121 is not applicable for this substance.

It may be assumed that the adsorption coefficients of Reactive Red 45:1 are below that of the reference item acetanilide (log Koc, soil < 1.26 and log Koc, sludge < 1.52).

Key value for chemical safety assessment

Koc at 20 °C:

33

Additional information

It may be assumed that the adsorption coefficients of Reactive Red 45:1 are below that of the reference item acetanilide (log Koc, soil < 1.26 and log Koc, sludge < 1.52). The corresponding Koc values are: <18 in soil and <33 in sludge.