Bis(2-ethylhexyl) cyclohexane-1,4-dicarboxylate

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:

2010-04-20 to 2010-04-21

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

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))

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Specific details on test material used for the study:

Batch No.: 20091203
Purity: 99.42%

Radiolabelling:

no

Test temperature:

40 °C.

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: Agilent Technologies 1050, incorporating autosampler and workstation
- Type, material and dimension of analytical (guard) column: Hyperclone CN 5µ (150 mm × 4.6 mm in diameter)
- Detection system: UV detector wavelength 210 nm.

MOBILE PHASES
- Type: Methanol: Reversed osmosis water 55:45 % v/v
- pH: 7.0
- Flow-rate: 1.0 ml/min
- Injection volume: 10 μL
- Solutes for dissolving test and reference substances: Methanol

DETERMINATION OF DEAD TIME
- Method: By reference substance formamide which is not retained by the column

REFERENCE SUBSTANCES
Below respectively substance, % purity, concentation (mg/L)
- Formamide 99.5 % 688 mg/L
- Acetanilide 99 %, 105 mg/L
- Phenol 99 %, 101 mg/L
- Atrazine 97.2 %, 100 mg/L
- Isoproturon 99.8 %, 94 mg/L
- Triadimenol 98.4 %, 106 mg/L
- Linuron 99.7 %, 100 mg/L
- Naphthalene ≥ 98.0 %, 105 mg/L
- Endosulfandiol 99.8 %, 100 mg/L
- Fenthion 98.3 %, 116 mg/L
- α-endosulfan 99.6 %, 118 mg/L
- Phenanthrene ≥ 97.0 %, 107 mg/L
- Diclofop-methyl 99.5 %, 102 mg/L
- DDT 98 %, 101 mg/L

CONSTRUCTION OF CALIBRATION CURVE
- A calibration curve was constructed from retention time data of the dead time and reference standard solutions.
- The capacity factors for the reference standards were calculated as (retention time ÷ dead time) - 1

ADSORPTION COEFFICIENT OF SAMPLE
- The adsorption coefficient (log Koc) was calculted as (Log k - A) ÷ B, where:
-- A = intercept of calibration curve
-- B = Slope of calibration curve

REPETITIONS
- Number of determinations: 2

Key result

Type:

log Koc

Value:

> 5.63

Temp.:

40 °C

Details on results (HPLC method):

- Retention times of reference substances used for calibration:
- Details of fitted regression line (log k' vs. log Koc): log k = 0.308 × log Koc -0.984, r = 0.966
- Graph of regression line attached
- Retention data for test substance: 13.197 mins, 13.282 mins.

Validity criteria fulfilled:

yes

Conclusions:

In a study to OECD guideline 121 (HPLC method), the adsorption/desorption coefficient (log Koc) of the test material was determined to be > 5.63.

Description of key information

Log koc > 5.63 (OECD 121)

Key value for chemical safety assessment

Koc at 20 °C:

427 000

Additional information

In a study to OECD guideline 121 (HPLC method), the adsorption/desorption coefficient (log Koc) of the test material was determined to be > 5.63.

[LogKoc: 5.63]