Dichlorotricyclo[8.2.2.24,7]hexadeca-1(12),4,6,10,13,15-hexaene, mixed isomers

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:

2016

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

Media:

soil/sewage sludge

Radiolabelling:

no

Test temperature:

20 °C

Details on study design: HPLC method:

INSTRUMENTAL PARAMETERS:
HPLC: Shimadzu (LC2010 CHT with LC solution software)
Column: C-18, Agilent XDB-CN [150 mm x 4.6 mm (i.d), 3.5 µm particle size]
Wave Length: 210 nm
Mobile Phase: Solvent A: Acetonitrile (55%); Solvent B: Milli-Q water (45%)
Injection Volume: 10 µL
Flow Rate: 0.8 mL/minute

ANALYSIS OF SAMPLES:
The diluted reference standard solutions and test item diluted solution were injected individually in duplicate and corresponding retention times (tR) were recorded. The Mixture solution containing reference standards was also injected before and after the injection of the test item in duplicate.

Preparation of Test Item Solution:
Weight (mg) of Sample: 11.67
Final Volume (mL): 10
Volume made using: Acetonitrile
Dilution of Solution: Solution taken (mL): 0.10; Final volume (mL): 10; Solution taken (mL): 1.0; Final volume (mL): 10; Volume made using: Mobile Phase

Determination of Dead Time (t0):
The dead time (t0) was determined by injecting thiourea solution onto the HPLC and retention time was recorded.

Reference Standards:
Phenol, atrazine, linuron, naphthalene, phenanthrene and Lambda cyhalothrin.
The study was performed using cyanopropyl column at constant temperature (20 +/- 0.5 °C) and 210 nm wavelength using, acetonitrile: water (45:55 v/v) as mobile phase.
Thiourea was used as inert material and its mean retention time was 2.142 minutes.

Calculation of Capacity Factor and Preparation of Calibration Curve:
The capacity factor (k) was calculated for each Reference Standards from t0 and respective tR by using the following formula:
k= (tR - t0)/t0
t0 =Mean retention time of inert substance
tR=Mean retention time of Reference Standard
The log of capacity factor (k) for each Reference Standard was calculated. The log k values of the Reference Standards were plotted against their log Koc values obtained from the batch equilibrium method (Ref. OECD Guidelines N° 121).

Calculation of Koc of Test Item from Calibration Curve
The capacity factor (k) and log k for the test item was calculated:
Log Koc = a + [(b X (log k)]
Where,
a = Constant
b = Slope

Key result

Sample No.:

#1

Type:

log Koc

Value:

4.85 dimensionless

Temp.:

20 °C

Details on results (HPLC method):

The mean retention times of the Reference Standards phenol, atrazine, linuron, naphthalene, phenanthrene and lambda cyhalothrin were 2.834, 3.109, 3.716, 4.064, 4.838 and 8.765 minutes, respectively.
The calculated capacity factors (k) for Reference Standards were 0.323, 0.451, 0.735, 0.897, 1.259 and 3.092, respectively.
Calculated log k was plotted against log Koc and calibration curve was established and correlation coefficient (R) was 0.9879.

The mean retention time of DPX-C (Di-Cloro-Di-p-Xililene) was 6.866 minutes.
The capacity factor (k) and log k were 2.205 and 0.3434, respectively.
The calculated log Koc of the DPX-C was 4.85.

Validity criteria fulfilled:

yes

Conclusions:

The calculated log Koc of the DPX-C (Di-Cloro-Di-p-Xililene) was 4.85, which indicated that the substance is hardly mobile in soil and sewage sludge.

Description of key information

The calculated log Koc of the DPX-C (Di-Cloro-Di-p-Xililene) was 4.85, which indicated that the substance is hardly mobile in soil and sewage sludge.

Key value for chemical safety assessment

Koc at 20 °C:

70 795

Additional information

The calculated log Koc of the DPX-C (Di-Cloro-Di-p-Xililene) was 4.85, which indicated that the substance is hardly mobile in soil and sewage sludge.

[LogKoc: 4.85]