(p-ammoniophenyl)bis(2-hydroxyethyl)ammonium sulphate

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:

From 2016-01-20 to 2016-09-29

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

All the validity criteria are met except the fact that no reference substance was eluted before the HPLC was used with A050. The Koc is extrapolated. However it was considered that the Koc is consistent with low adsorbing compounds as estimated from the linear response of the references substances used.

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))

Version / remarks:

January 22, 2001

Deviations:

no

GLP compliance:

yes

Type of method:

HPLC estimation method

Test temperature:

25°C

Details on study design: HPLC method:

Equipment:
- Detector: Agilent 1100 G1314A
- Pump: Agilent 1100 G1312A (Binary Pump)
- Data Acquisition: Empower 3
- Autosampler: Agilent 1100 G1313A
- Degasser: Agilent 1100 G1379A
- Column Heater: Agilent 1100 G1316A
- Column: Zorbax SB-CN, 250 mm × 4.6 mm, 5 μm

Isocratic Mobile Phase:
- Component A: Methanol
- Component B: 0.01 M Citric Acid (pH 6.51)
- Ratio: 47:53

Operating Conditions:
- Flow Rate: 1.0 mL/min
- Column Temperature: 25 °C
- Injection Volume: Various (5 or 10 μL)
- Detection: UV (λ = 254 nm)

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

REFERENCE SUBSTANCES
- Identity : Thiourea, Phenol, N,N-Dimethylbenzamide, Atrazine, Naphthalene, Phenanthrene.
- Stock solutions were prepared for each reference substance by weighing an amount of the respective substance into separate volumetric flasks, dissolving with methanol, and correcting for purity.
- Two mixed standard solutions were prepared by adding aliquots of the stock solutions and then vortexed to mix.

TEST SUBSTANCE PREPARATION
The test substance solution was prepared by adding 0.01102 g of Colipa A050 to a Class A 10-mL volumetric flask and bringing to volume with methanol. Correcting for purity, the concentration of this solution was 1.01 mg/ mL. A single peak was observed by HPLC analysis.

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: not reported
- Quantity of reference substances: not reported
- Intervals of calibration: log Koc = 1.32 to 4.09

REPETITIONS
- Number of determinations : A sample containing Colipa A050 and thiourea was injected in duplicate to estimate the adsorption coefficient of the test substance. The standard mix of the reference substances was injected before and after the test substance injections with thiourea.

EVALUATION
- Calculation of capacity factors k' = (TR-T0)/T0
with TR (the mean retention time for the component),
and T0 (the system dead time, that is, the mean retention time of thiourea)
- Calibration curve : For the reference substances, the logarithm of the capacity factor was plotted against the logarithm of the distribution coefficient to derive a calibration graph, fitted linearly : log Koc = slope * log K' + constant
- Determination of the log Koc value: The estimated distribution coefficient for the test substance was calculated from the capacity factor by derivation from the calibration graph equation above

Key result

Sample No.:

#1

Type:

Koc

Value:

4.3 L/kg

pH:

6.6

Temp.:

25 °C

Key result

Sample No.:

#1

Type:

log Koc

Value:

0.63 dimensionless

pH:

6.6

Temp.:

25 °C

Key result

Sample No.:

#2

Type:

Koc

Value:

4.3 L/kg

pH:

6.6

Temp.:

25 °C

Key result

Sample No.:

#2

Type:

log Koc

Value:

0.63 dimensionless

pH:

6.6

Temp.:

25 °C

Details on results (HPLC method):

- Retention times of reference substances used for calibration: see the table in "Any other information on results incl. tables"
- Details of fitted regression line (log k' vs. log Koc): y=1.7671 x + 1.7482 ; R2=0.9054
- Retention data for test substance: 3.769 and 3.773

Reference Substance Log k'Values

Reference substance	LogKoc	Injection No.	Retention time in min.	K’	Log K’	MeanLog K’
Thiourea	na	1404	3.051	na	na	na
		1459	3.057
Thiourea	na	1452	3.056	na	na	na
		1465	3.057
Phenol	1.32	1452	4.819	0.58	-0.24	-0.24
		1462	4.821	0.58	-0.24	-0.24
N-NDimethylbenzamide	1.52	1452	5.071	0.66	-0.18	-0.18
		1462	5.075	0.66	-0.18	-0.18
4-Nitrobenzamide	1.66	1404	4.939	0.62	-0.21	-0.21
		1459	4.958	0.62	-0.21	-0.21
Atrazine	1.81	1452	10.332	2.38	0.38	0.38
		1462	10.336	2.38	0.38	0.38
Naphthalene	2.75	1452	14.807	3.84	0.58	0.58
		1462	14.807	3.84	0.58	0.58
Phenanthrene	4.09	1452	48.502	14.87	1.17	1.17
		1462	48.328	14.81	1.17	1.17

na =not applicable

Regression results : R2 = 0.9054 ;Slope=1.767 ; Intercept = 1.7482

 

Estimation of Log Koc for Colipa A050

SampleID	Injection No.	Thiourea Retentiontime (min.)	Test subst. Retention time (min.)	K’	Log K’	LogKoc
Test Mix 2	1410	3.056	3.769	0.23	-0.63	0.63
Test Mix 2	1456	3.058	3.773	0.23	-0.63	0.63
Mean log Koc						0.63
Mean Koc						4.3

 

Validity criteria fulfilled:

yes

Remarks:

All the validity criteria are met except that no reference compounds eluted before Colipa A050. However it was considered that the Koc is consistent with low adsorbing compounds as estimated from the linear response of the reference substances used.

Conclusions:

The Adsorption Coefficient, log KOC, of 2-[[(4-aminophenyl)-(2-hydroxyethyl)]amino]ethanol sulphate, for soil was 0.63 (KOC 4.3 L/kg) measured by HPLC method (OECD 121).

Executive summary:

The Adsorption Coefficient of 2-[[(4-aminophenyl)-(2-hydroxyethyl)]amino]ethanol sulphate was determined following OECD 121 (High Performance Liquid Chromatography (HPLC)) and under GLP. The Koc of the tested substance was determined through comparison to compounds with known Koc values based upon the retention times on an HPLC analytical column.

A solution containing the tested substance and thiourea (an unretained organic compound used to establish dead time) was prepared and analyzed on a liquid-phase chromatograph equipped with a UV detector, a column heater set at 25 °C, and an analytical column packed with cyanopropyl solid phase.

4-nitrobenzamide, atrazine, N,N-dimethylbenzamide, naphthalene, phenanthrene, and phenol were used as reference substances and analyzed under the same analytical conditions. Samples of the tested substance were analyzed in duplicate and the standard mix of the reference substances was injected before and after the tested substance and thiourea. The measured retention times (consistent with those listed in the guidelines) and literature documented Koc values of the reference substances were used to construct a calibration graph. The Koc value of the tested substance was then determined using the calibration curve.

All the validity criteria are met, except that there were no reference compounds that eluted before the tested substance and the Koc is extrapolated. However it was considered that the determination of the Koc by this method was consistent with low adsorbing compounds as estimated from the linear response of the reference substances used.

At 25 °C, the log of the adsorption coefficient of 2 -[[(4 -aminophenyl)-(2 -hydroxyethyl)]amino]ethanol sulphate to soil was determined to be 0.63 (Koc = 4.3 L/kg) by HPLC estimation method.

Description of key information

The Adsorption Coefficient, log KOC, of 2-[[(4-aminophenyl)-(2-hydroxyethyl)]amino]ethanol sulphate, for soil was 0.63 (Koc 4.3 L/kg) measured by HPLC method (OECD 121).

Key value for chemical safety assessment

Koc at 20 °C:

4.27

Additional information

The Adsorption Coefficient of 2-[[(4-aminophenyl)-(2-hydroxyethyl)]amino]ethanol sulphate was determined following OECD 121 (High Performance Liquid Chromatography (HPLC)) and under GLP. The Koc of the tested substance was determined through comparison to compounds with known Koc values based upon the retention times on an HPLC analytical column.

A solution containing the tested substance and thiourea (an unretained organic compound used to establish dead time) was prepared and analyzed on a liquid-phase chromatograph equipped with a UV detector, a column heater set at 25 °C, and an analytical column packed with cyanopropyl solid phase.

4-nitrobenzamide, atrazine, N,N-dimethylbenzamide, naphthalene, phenanthrene, and phenol were used as reference substances and analyzed under the same analytical conditions. Samples of the tested substance were analyzed in duplicate and the standard mix of the reference substances was injected before and after the tested substance and thiourea. The measured retention times (consistent with those listed in the guidelines) and literature documented Koc values of the reference substances were used to construct a calibration graph. The Koc value of the tested substance was then determined using the calibration curve.

All the validity criteria are met, except that there were no reference compounds that eluted before the tested substance and the Koc is extrapolated. However it was considered that the determination of the Koc by this method was consistent with low adsorbing compounds as estimated from the linear response of the reference substances used.

At 25 °C, the log of the adsorption coefficient of 2 -[[(4 -aminophenyl)-(2 -hydroxyethyl)]amino]ethanol sulphate to soil was determined to be 0.63 (Koc = 4.3 L/kg) by HPLC estimation method.

[LogKoc: 0.63]

[LogKoc: 0.63]