Cashew (Anacardium occidentale) Nutshell Extract, Decarboxylated, Distilled, oligomerisation products with 1-chloro-2,3-epoxypropane

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

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))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Media:

soil/sewage sludge

Radiolabelling:

no

Test temperature:

25 ± 1 °C.

Details on study design: HPLC method:

EQUIPMENT
- Pump: Gynkotek Pump M480 G, Autosampler ASI-100
- Type, material and dimension of analytical (guard) column:
Reprosil-Pur CN Dr. Maisch, 4.6 mm i.D., 125 mm length, particle size 3 µm
- Detection system: Dionex, UVD 170S

MOBILE PHASES
- Type: mixture of 55% methanol and 45% water, isocratic
- Experiments with additives carried out on separate columns: no
- pH: approx. 6

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

REFERENCE SUBSTANCES
- Identity:
Name CAS-No. Concentration injected
Sodium nitrate 7631-99-4 2.00 mg/L
Phenol 108-95-2 4.00 mg/L
Methylbenzoate 93-58-3 2.00 mg/L
Naphthalene 91-20-3 2.00 mg/L
1,2,3-Trichlorbenzene 87-61-6 4.00 mg/L
Phenanthrene 85-01-8 6.00 mg/L
DDT 50-29-3 19.7 mg/L


DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: no information
- Quantity of reference substances: no information
- Intervals of calibration: no information

REPETITIONS
- Number of determinations: 6 for reference substances and 3 for HEPES

EVALUATION
- Calculation of capacity factors k': The capacity factor k´ for every peak was calculated as follows: K'= (tr -to)/to, with tr=retention time and
to=dead time (retention time of sodium nitrate)
- Calculation of retention times: retention time of peaks were used
- Determination of the log Koc value:
The calibration function was drawn up from the six measurements of the capacity factors of the reference items. By plotting the (known) log KOC
values of the reference items against the mean log capacity factors and performing linear regression, a calibration function was obtained.
With the calculated capacity factors for the test item, each log KOC from the three determinations was calculated. Finally, mean and standard
deviation of the log KOC were calculated.

Type:

log Koc

Value:

> 5.63

Temp.:

25 °C

Details on results (HPLC method):

- Retention times (mean in minutes) of reference substances used for calibration:
Sodium nitrate 1.215
Phenole 2.855
Methylbenzoate 3.241
Naphthaline 4.418
1,2,3-Trichlorbenzene 5.024
Phenanthrene 6.940
DDT 13.955
- Details of fitted regression line (log k' vs. log Koc): log k’ = 0.2052 * logKOC - 0.1476 (r²=0.9989)
- Average retention data for test substance: 2.085 (SD = 0.01)

Retention Times Test Item

Measurement	RT Peak 1	RT Peak 2	RT Peak 3	RT Peak 4
	min.	min.	min.	min.
Measurement 1	5.365	6.029	7.066	8.765
Measurement 2	5.375	5.995	7.037	8.744
Measurement 3	5.380	6.018	7.063	8.754
Mean	5.373	6.014	7.055	8.754
Standard Deviation	0.008	0.017	0.016	0.011
Measurement	RTPeak5	RTPeak6	RTPeak7	RTPeak8
	min.	min.	min.	min.
Measurement 1	11.841	14.711	19.092	28.142
Measurement 2	11.716	14.658	18.992	27.996
Measurement 3	11.737	14.647	18.922	27.753
Mean	11.765	14.672	19.002	27.964
Standard Deviation	0.067	0.034	0.085	0.197

Using the correlation log k’ / log K_OC, the log K_OCof the peaks of the test item CARDOLITE NC-513 was estimated as > 5.63 (result of three determinations), as peaks 1 – 5 are minor peaks and peaks 4 – 8 lay outside the calibrated range.

Log koc of test item peaks

Peak	Mean retention time [min]	Log KOC+sd
1	5.373	4.297 ± 0.005
2	6.014	4.661 ± 0.009
3	7.055	5.164 ± 0.007
4	8.754	5.825 ± 0.004
5	11.765	6.703 ± 0.017
6	14.672	7.344 ± 0.007
7	19.002	8.082 ± 0.013
8	27.964	9.168 ± 0.020

Validity criteria fulfilled:

yes

Conclusions:

In a GLP-study according to OECD test guideline 121, the log koc of the registered substance was determined as > 5.63.

Executive summary:

The study was performed using a HPLC with a cyanopropyl chemical bound resin on a silica basecolumn. Six reference items with different retention times were used to produce a calibration curve, since retention time on cyanopropyl columns and K_OCare correlated. The reference items were chosen on behalf of the retention time of the test item CARDOLITE NC-513 on the column.

A solvent blank followed by three injections of a solution of the reference items were analysed with HPLC, then three injections of a solution of the test item; and finally three injections of the solution with the reference items, totalling to ten runs.

For each reference item, the capacity factor k’ was calculated from the retention time of sodium nitrate and the retention time of the respective reference item. A calibration function was set up using the literature values for K_OCof the reference items and the mean capacity factor of the six determinations. In the graph Log k’ versus Log K_OC, linear regression was performed, giving r²= 0.983 and r = 0.992.

The chromatogram of the test item gave eight peaks. With the help of the calibration function log K versus log K_OC, the corresponding log K_OCs were determined.

As the major peaks lay outside the calibrated range, the log K_OCof the test item CARDOLITE NC-513 should be stated as > 5.63.

Description of key information

estimated log Koc at 25 °C (determined using OECD 121, HPLC estimation method; GLP): > 5.63

Additional information

The substance has a high adsorption/desorption coefficient, which indicates that it will have high likelihood of partitioning to sediments, organic matter in soil or sludge in the sewer system.