Fatty acids, linseed-oil, reaction products with 2-amino-2-(hydroxymethyl)-1,3-propanediol and formaldehyde

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:

2016-07-28 to 2017-11-21

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))

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:

soil/sewage sludge

Radiolabelling:

no

Test temperature:

The temperature was held constant at 25 ± 0.5 °C by use of a HPLC column oven.

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: HPLC with a cyanopropyl chemical bound resin on a silica base column.
HPLC_3, Components: Degasser G1379A, Quaternary pump G1311A, Autosampler G1313A, Column compartment G1316A, UV/VIS-Detector MWD G1365B
- Type, material and dimension of analytical (guard) column: moderately polar analytical columns packed with a cyanopropyl solid phase containing lipophilic and polar moieties. Column compartment G1316A; Reprosil-Pur CN 3 μm Dr. Maisch, 4.6 mm x 125 mm, pre-column CN 3*4 mm
- Detection system: UV/VIS-Detector MWD G1365B

MOBILE PHASES
- Type: A mixture of 55% methanol and 45% water, isocratic, was used. The mix was produced by mixing of 275 mL methanol and 225 mL water resp. 55 mL methanol and 45 mL water.
- pH: 7.00 (measured once)
- Solutes for dissolving test and reference substances: Because low water solubility of the test item was expected, the test item solution was prepared in methanol.

DETERMINATION OF DEAD TIME
- Method: by means of homologous series / by inert substances which are not retained by the column
The dead time t0 was measured by using an unretained compound (sodium nitrate) which was included in the mix of the reference items. Dead time is 1.071± 0.004 minutes, with a RSD of 0.39%.

REFERENCE SUBSTANCES
- Identity: Six reference items with different retention times were used to produce a calibration curve. The reference items were chosen according to the pre-test.
The reference items were dissolved in the mobile phase.
- Sodium nitrate CAS-No.: 7631-99-4 Batch: SZBE1280V Purity: ≥ 99.5 % Concentration injected: 2.0 mg/L
- Phenol CAS-No.: 108-95-2 Batch: BCBN1982V Purity: ≥ 99.0 % Concentration injected: 4.0 mg/L
- Methylbenzoate CAS-No.: 93-58-3 Batch: BCBM9662V Purity: ≥ 99.5 % Concentration injected: 2.0 μL/L
- Naphthalene CAS-No.: 91-20-3 Batch: BCBM9272V Purity: ≥ 99.7 % Concentration injected: 2.0 mg/L
- 1,2,4-Trichlorobenzene* CAS-No.: 120-82-1 Batch: 774971 Purity: 99.9 % Concentration injected: 4.0 mg/L (* 1,2,4- Trichlorobenzene was used due to an error instead of 1,2 3-Trichlorbenzene during the pretest. This is stated as uncritical, because this reference item was not used for final evaluation.)
- 1,2,3-Trichlorobenzene CAS-No.: 87-61-6 Batch: MKBN5959V Purity: 99.0 % Concentration injected: 4.0 mg/L
- Phenanthrene CAS-No.: 85-01-8 Batch: 10506 Purity: 99.5 % Concentration injected: 3.0 mg/L
- 4,4’-DDT CAS-No.: 50-29-3 Batch: SZBE057XV Purity: 98.7 % Concentration injected: 10.0 mg/L

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: 20 μL
- Quantity of reference substances: 20 μL

REPETITIONS
- Number of determinations: 3

EVALUATION
- Calculation of capacity factors k': k' = (tR - t0)/t0 , where tR=retention time and t0= dead time (retention time of sodium nitrate)
- Calculation of retention times: determined by direct reading
- Determination of the log Koc value: log Koc was calculated from the capacity factor as follows: log Koc = (log k’ + 0.1181) / 0.245
A calibration function was set up using the literature values for Koc of the reference items and the mean capacity factor of the six determinations. In the graph Log k’ versus Log Koc, linear regression was performed, giving r^2 = 0.996 and r = 0.998.
Using the correlation log k’ / log Koc, the log Koc of the peak 1 of the test item VOELOFA Monomer was calculated as 2.362 ± 0.002 (mean ± standard deviation). The log Koc of the test item is stated as 2.363 - > 5.63 therefore.

Key result

Sample No.:

#1

Type:

log Koc

Value:

2.362 dimensionless

Sample No.:

#2

Type:

log Koc

Value:

> 5.63 dimensionless

Remarks on result:

other: log Koc of DDT

Sample No.:

#3

Type:

log Koc

Value:

> 5.63 dimensionless

Remarks on result:

other: log Koc of DDT

Details on results (HPLC method):

See Table 2 and 4 below.

The study was performed using a HPLC with a cyanopropyl chemical bound resin on a silica base column. Six reference items with different retention times were used to produce a calibration curve, since retention time on cyanopropyl columns and KOO are correlated. The reference items were chosen according to the pre-test. 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, in total ten runs.

For the first 32 minutes an isocratic program was used (retention time of DDT with the highest log Koc: 21.5 minutes). The HPLC program was prolonged with mobile phase 100% methanol to elute further test item peaks and to show, that test item peaks are detectable.

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 KOC of the reference items and the mean capacity factor of the six determinations. ln the graph Log k’ versus Log KOC, linear regression was performed, giving r2 = 0.996 and r = 0.998.

The test item showed a small peak with retention time 4.164 minutes in the isocratic part of the HPLC program and two peaks with retention times of 36.404 and 36.691 minutes, eluted in the HPLC program after change of eluent to 100% methanol. Because the retention times of the test item peaks 2 and 3 are higher than the retention time of DDT (21.5 minutes), the log KOO of peak 2 and peak 3 of the test item is stated as > 5.63 (log KOO of DDT).

Using the correlation log k’ / log Koo, the log KOO of the peak 1 of the test item VOELOFA Monomer was calculated as 2.362 i 0.002 (mean i standard deviation). The log KOO of the test item is stated as 2.363 - > 5.63 therefore. These values are the result of three independent determinations.

The dead time t0 was measured by using an unretained compound (sodium nitrate) which was included in the mix of the reference items.

Table 1 Method parameters HPLC

Time (min)	Eluent 1 [%] methanol/water 55/45 (% v/v), degassed	Eluent 2 [%] Methanol
0	100	0
32	100	0
33	0	100
38	0	100
39	100	0
44	100	0

* For the first 32 minutes an isocratic program was used (retention time of DDT with the highest log Koc: 21.5 minutes). The HPLC program was prolonged with mobile phase 100% methanol to elute further test item peaks.

Table 2 Retention Times (RT) Reference Items.

Compound	RT1	RT2	RT3	RT4	RT5	RT6
	min	min	min	min	min	min
Sodium nitrate	1.069	1.076	1.076	1.065	1.070	1.071
Phenole	2.886	2.887	2.888	2.886	2.888	2.887
Methylbenzoate	3.218	3.219	3.219	3.216	3.219	3.218
Naphthaline	4.953	4.954	4.955	4.945	4.953	4.947
1,2,3-Trichlorbenzene	6.023	6.023	6.023	6.008	6.016	6.011
Phenanthren	8.646	8.646	8.647	8.617	8.627	8.618
DDT	21.590	21.600	21.576	21.485	21.499	21.480

Table 3 Log k' and log Koc of Reference Items

Compound	log k'	log Koc
Phenole	0.229	1.32
Methylbenzoate	0.302	1.80
Naphthaline	0.559	2.75
1,2,3-Trichlorbenzene	0.664	3.16
Phenanthren	0.849	4.09
DDT	1.281	5.63

Table 4 Retention Times (RT) Test Item.

Measurement	RT1	RT2	RT3
	min	min	min
Measurement 1	4.167	36.409	36.696
Measurement 2	4.163	36.400	36.691
Measurement 3	4.162	36.401	36.685
Mean	4.164	36.404	36.691
Standard Deviation	0.003	0.005	0.005

The calculated values are presented in the following table:

 

Table 5: Capacity Factor, log Capacity Factor, log Koc Test Item

Peak 1 Test Item	k’	log k’	log Koc
Measurement 1	2.8905	0.4610	2.364
Measurement 2	2.8861	0.4603	2.361
Measurement 3	2.8856	0.4602	2.361
Mean			2.362
Standard deviation			0.002
Peak 2 Test Item	k’	log k’	log Koc
Measurement 1	n.c.*	n.c.*	n.c.*
Measurement 2	n.c.*	n.c.*	n.c.*
Measurement 3	n.c.*	n.c.*	n.c.*
Mean			n.c.*
Standard deviation			n.c.*
Peak 3 Test Item	k’	log k’	log Koc
Measurement 1	n.c.*	n.c.*	n.c.*
Measurement 2	n.c.*	n.c.*	n.c.*
Measurement 3	n.c.*	n.c.*	n.c.*
Mean			n.c.*
Standard deviation			n.c.*

* n.c. = not calculable, because the peak eluted not in the isocratic part of the program

 

log Koc was calculated from the capacity factor as follows:

log Koc = (log k’ + 0.1181) / 0.245

Validity

The test item peak showed a small peak with retention time 4.164 minutes in the isocratic part of the HPLC program and two peaks with retention times of 36.404 and 36.691 minutes, eluted in the HPLC program after change of eluent to 100% methanol.

The peaks eluted with very low standard deviations. The determination was precise. The calculation 0f the log KOO of the test item peaks 2 and 3 is not possible, because the peaks 2 and 3 eluted in the not isocratic part 0f the HPLC program. Extrapolation is not possible therefore. Because the retention times of the test item peaks 2 and 3 are higher than the retention time of DDT (21.5 minutes) the log KOO of peak 2 and peak 3 of the test item is stated as > 5.63 (log KOO of DDT).

Using the correlation log k’ / log Koo, the log KOO of the peak 1 of the test item VOELOFA Monomer was calculated as 2.362 ± 0.002 (mean ± standard deviation).

Validity criteria fulfilled:

yes

Conclusions:

The test item showed a small peak with retention time 4.164 minutes in the isocratic part of the HPLC program and two peaks with retention times of 36.404 and 36.691 minutes, eluted in the HPLC program after change of eluent to 100% methanol.
Because the retention times of the test item peaks 2 and 3 are higher than the retention time of DDT (21.5 minutes), the log Koc of peak 2 and peak 3 of the test item is stated as > 5.63 (log Koc of DDT).
Using the correlation log k’ / log Koc, the log Koc of the peak 1 of the test item VOELOFA Monomer was calculated as 2.362 ± 0.002.
The log KOC of the test item is stated as 2.363 - > 5.63.

Executive summary:

The study was performed using a HPLC with a cyanopropyl chemical bound resin on a silica base column. The experiment was conducted in accordance with the OECD 121 (2001), and in compliance with the EU GLP standard. Six reference items with different retention times were used to produce a calibration curve, since retention time on cyanopropyl columns and Koc are correlated. The reference items were chosen according to the pre-test. 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, in total ten runs.

For the first 32 minutes an isocratic program was used (retention time of DDT with the highest log Koc: 21.5 minutes). The HPLC program was prolonged with mobile phase 100% methanol to elute further test item peaks and to show, that test item peaks are detectable. 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 Koc of the reference items and the mean capacity factor of the six determinations. ln the graph Log k’ versus Log Koc, linear regression was performed, giving r2 = 0.996 and r = 0.998.

The test item showed a small peak with retention time 4.164 minutes in the isocratic part of the HPLC program and two peaks with retention times of 36.404 and 36.691 minutes, eluted in the HPLC program after change of eluent to 100% methanol. Because the retention times of the test item peaks 2 and 3 are higher than the retention time of DDT (21.5 minutes), the log Koc of peak 2 and peak 3 of the test item is stated as > 5.63 (log Koc of DDT). Using the correlation log k’ / log Koc, the log Koc of the peak 1 of the test item VOELOFA Monomer was calculated as 2.362 ± 0.002 (mean ± standard deviation).

The log Koc of the test item is stated as 2.363 - > 5.63 therefore.

These values are the result of three independent determinations.

Description of key information

In an adsorption study according to OECD guideline 121 (Estimation of the Adsorption Coefficient (Koc ) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC)) and GLP a log Koc of 2.364 (at 25 °C) was estimated via HPLC, corresponding to a Koc of 231 (at 25 °C).

Key value for chemical safety assessment

Koc at 20 °C:

231

Additional information

The adsorption/desorption characteristics of VOELOFA Monomer was estimated in a HPLC experiment.  The experiment was conducted in accordance with the OECD 121 (2001), and in compliance with the EU GLP standard. The test was performed at 25 °C, with a mobile phase consisting of 100 % methanol. A 200 mg/L sample of VOELOFA Monomer was analyzed via HPLC with a cyanopropyl chemical bound resin on a silica base column. Calibrations were performed using six reference items for soil and sewage sludge with known Koc values given by the guidelines. The reference items were measured twice, once before and once after the measurement of the test item. Dead time of the HPLC-system was determined with sodium nitrate. Using the correlation log k’ / log KOC, the log KOC of the peak 1 of the test item VOELOFA

Monomer was calculated as 2.362 ± 0.002. Because the retention times of the test item peaks 2 and 3 are higher than the retention time of DDT (21.5 minutes) the log Koc of peak 2 and peak 3 of the test item is stated as > 5.63 (log Koc of DDT).