Registration Dossier

Environmental fate & pathways

Adsorption / desorption

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
adsorption / desorption: screening
Type of information:
experimental study
Adequacy of study:
key study
Study period:
01 July 2014 to 13 March 2015
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP guideline study.
Qualifier:
according to
Guideline:
OECD Guideline 121 (Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC))
Deviations:
no
Qualifier:
according to
Guideline:
EU Method C.19 (Estimation of the Adsorption Coefficient (KOC) on Soil and Sewage Sludge Using High Performance Liquid Chromatography (HPLC))
Deviations:
no
GLP compliance:
yes (incl. certificate)
Type of method:
HPLC estimation method
Media:
other: not applicable
Test temperature:
30 °C
Details on study design: HPLC method:
PREPARATION OF THE DEAD TIME SOLUTION
- The dead time was determined by measuring the retention time of formamide (99.94%) at 609 mg/L in methanol:water (55:45 v/v).

PREPARATION OF THE SAMPLE SOLUTION
- Test item (2.5053 g) was diluted to 50 mL with tetrahydrofuran.

DETERMINATION OF RETENTION TIME
- The sample, dead time and reference standard solutions were injected in duplicate using the high performance liquid chromatography (HPLC) parameters described below.
- The mobile phase was ramped to 100% tetrahydrofuran (acidified with trifluoroacetic acid at 25 % in propan-2-ol) shortly after elution of the last reference standard to elute the highly retained test item components. This was carried out for the sample and sample blank injections only.
- HPLC system: Agilent Technologies 1200 incorporating workstation and autosampler
- Detector: Agilent variable wavelength detector (VWD)
- Column: Phenomenex Luna CN 5 µm (150 x 4.6 mm id)
- Column temperature: 30 °C
- Flow-rate: 1.0 mL/min
- Mobile phase: methanol:purified water (55:45 v/v)
- pH of mobile phase: 5.0 adjusted with trifluoroacetic acid
- Injection volume: 5 µL
- UV detector wavelength: 230 nm

CALCULATION
- Capacity factors for the reference standards and the test item were determined using the equation k' = (tr - t0) / t0 where k' = capacity factor; tr = retention time (min); t0 = dead time (min).
- A correlation of log10 k' versus Log10 Koc of the calibration standards was plotted using linear regression (see Figure 3.1, attached).
- Log10 Koc values for the reference standards were those quoted in OECD Method 121.
- The log10 Koc value for the test item was calculated using the equation log10 Koc = (log10 k' - A) / B where Koc = adsorption coefficient; k' = capacity factor; A = intercept of the calibration curve; B = slope of the calibration curve.

Key result
Sample No.:
#1
Type:
log Koc
Remarks:
log10 Koc of > 5.63
Value:
> 5.63 L/kg
pH:
5
Temp.:
30 °C
Remarks on result:
other: The adsorption coefficient of the test item has been determined to be greater than 4.27 x 10E5 with a log10 Koc of > 5.63.
Details on results (HPLC method):
- Typical chromatograms for dead time, reference standards and sample are attached.
- Retention times of the dead time and and retention times, capacity factors and log10 Koc values for the reference standards are shown in Table 3.2 and Table 3.3 (attached).
- The retention times, capacity factor and log10 Koc value determined for the sample are shown in Table 3.4 (attached).
Adsorption and desorption constants:
HPLC screening method designed to be compatible with Method C.19 of Commission Regulation (EC) No 440/2008 of 30 May 2008 and Method 121 of the OECD Guidelines for Testing of Chemicals, 22 January 2001.

RESULT
The adsorption coefficient of the test item has been determined to be greater than 4.27 x 10E5 with a log10 Koc of > 5.63.
Validity criteria fulfilled:
yes
Conclusions:
The adsorption coefficient of the test item has been determined to be greater than 4.27 x 10E5 with a log10 Koc of > 5.63.
Executive summary:

GUIDELINE

HPLC screening method designed to be compatible with Method C.19 of Commission Regulation (EC) No 440/2008 of 30 May 2008 and Method 121 of the OECD Guidelines for Testing of Chemicals, 22 January 2001.

RESULT

The adsorption coefficient of the test item has been determined to be greater than 4.27 x 10E5 with a log10 Koc of > 5.63.


Description of key information

The adsorption coefficient of the test item was determined to be greater than 4.27 x 10E5 with a log10 Koc of > 5.63 (OECD 121 and EU Method C.19).

Key value for chemical safety assessment

Koc at 20 °C:
426 580

Additional information

The determination was performed using the HPLC screening method designed to be compatible with Method C.19 of Commission Regulation (EC) No 440/2008 of 30 May 2008 and Method 121 of the OECD Guidelines for Testing of Chemicals, 22 January 2001. The adsorption coefficient of the test item was determined to be greater than 4.27 x 10E5 with a log10 Koc of > 5.63.

[LogKoc: 5.63]