Alcohols, C11-15-secondary, ethoxylated

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:

10 March to 14 September 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study conducted in accordance with internationally accepted guidelines

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))

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:

other: Cyano-propyl bonded phase (HPLC column)

Radiolabelling:

no

Test temperature:

25°C

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: Liquid Chromatograph
- Type: Hewlett Packard 1050
- Type, material and dimension of analytical column: Supelcosil LC-PCN (15 cm x 3 mm internal diameter)
- Detection system: UV set at 210 nm (reference mixture); Shodex RI 71 Refractive Index (samples)


MOBILE PHASES
- Type: Methanol:water (55:45 v/v)
- Experiments with additives carried out on separate columns: no
- pH: unbuffered (substance not ionisable)
- Solvents for dissolving test and reference substances: HPLC mobile phase

DETERMINATION OF DEAD TIME
- Method: by inert substance which is not retained by the column (formamide)

REFERENCE SUBSTANCES
- Identity: acetanilide; nitrobenzene; naphthalene; 2-methylnaphthalene; anthracene; DDT

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: 20 ng
- Quantity of reference substances: 0.1-4 ng
- Intervals of calibration: approximately 1 log unit

REPETITIONS
- Number of determinations: Two

EVALUATION
- Calculation of capacity factors k': (retention time of sample/reference - retention time deadtime standard) / retention time deadtime standard)
- Calculation of retention times: observed retention time - deadtime
- Determination of the log Koc value: A calibration plot of log10 k versus log10 Koc was constructed for the reference standards. The logarithm of the capacity factors for the test substance was then calculated and the log10 Koc values determined by interpolation.

Type:

Koc

Value:

>= 14 000 - <= 420 000 dimensionless

Details on results (HPLC method):

- Retention times of reference substances used for calibration:

Acetanilide: 0.98 min
Nitrobenzene: 1.09 min
Naphthalene: 1.26 min
2-Methynaphthalene 1.37 min
Anthracene: 1.71 min
DDT: 2.48 min

(mean of two determinations)


- Details of fitted regression line (log k' vs. log Koc): Linear regression (based on mean of standard runs A and B): log10Koc = 3.59 log10k + 4.58

- Graph of regression line attached: yes


- Average retention data for test substance: 1.55 to 2.61 minutes

Validity criteria fulfilled:

yes

Executive summary:

The main components of Softanol 30 were determined to have log₁₀K_ocvalues ranging from of 4.1 to 5.6.

These values are equivalent to K_oc= 1.4 x 10⁴ to 4.2 x 10⁵.

Description of key information

The main components of Softanol 30 were determined to have log10Koc values ranging from of 4.1 to 5.6.
These values are equivalent to Koc=   1.4 x 10E4    to   4.2 x E5.

Key value for chemical safety assessment

Koc at 20 °C:

14 000

Additional information

The Koc value selected is the worst case for the aquatic environment where the substance is known to have hazardous properties.

[LogKoc: 4.1]