Reaction mass of N1,N1'-(methanediyldibenzene-4,1 -diyl)diaryldiamine and 2-{4-[(4-aminophenyl)amino]benzyl}-N4-(4-{4-[(4-aminophenyl)amino]benzyl}phenyl)aryldiamine

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:

24 October 2014 to 26 January 2015

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

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))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Media:

soil/sewage sludge

Test temperature:

30 °C

Details on study design: HPLC method:

PERFORMANCE OF THE TEST
- Solutions of reference standards were prepared as shown in Table 3.1 (below).

PREPARATION OF THE DEAD TIME SOLUTION
- The dead time was determined by measuring the retention time of formamide (purity quoted by supplier: 99.94%) at 662 mg/L in methanol:water (55:45 v/v).

PREPARATION OF THE SAMPLE SOLUTION
- Test item (0.0245 g) was diluted to 100 mL with methanol.

DETERMINATION OF RETENTION TIME
- The sample, dead time and reference standard solutions were injected in duplicate using the High Performance Liquid Chromatography (HPLC) parameters shown in the table below.
- The mobile phase was ramped to 90 % tetrahydrofuran shortly after the 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.

CALCULATION OF CAPACITY FACTORS
- capacity factors were determined using the equation k’ = (tr – t0) / t0 where k’ = capacity factor; tr = retention time (min); t0 = dead time (min)

CONSTRUCTION OF THE CALIBRATON CURVE
- A correlation of Log10 k' versus log10 Koc of the calibration standards was plotted using linear
regression (Figure 3.1).
- The Log10 Koc values of the reference standards were those quoted in OECD Method 121.

ADSORPTION COEFFICIENT
- The Log10 Koc value 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.

Analytical monitoring:

no

Key result

Type:

log Koc

Value:

>= 1.63 - <= 5.63 dimensionless

pH:

8.5

Temp.:

30 °C

Details on results (HPLC method):

RESULTS
- Typical chromatographs are attached.
- The retention times of the dead time and the retention times, capacity factors and Log10 K0c values for the reference standards are shown in Tables 3.2 and 3.3 (below).
- The calibration curve is presented in Figure 3.1 (attached).
- The retention times, capacity factors and Log10 Koc values for the sample are shown in Table 3.4 (attached).
- Typical chromatography for the adsorption coefficient reference standards is shown in Appendix 2 (attached).

TABLE 3.2 – RETENTION TIMES OF THE DEAD TIME

Dead time	Retention time (mins) Injection 1	Retention time (mins) Injection 2	Mean retention time (mins)
Formamide	1.905	1.905	1.905

 

TABLE 3.3 – RETENTION TIMES, CAPACICITY FACTORS AND Log10 Koc VALUES FOR THE REFERENCE STANDARDS

Standard	Retention time (mins) Injection 1	Retention time (mins) Injection 1	Mean retention time (mins)	Capacity factor (k’)	Log10 k’	Log10 Koc
Acetanilide	2.609	2.604	2.607	0.369	-0.433	1.25
Atrazine	3.635	3.635	3.635	0.908	-4.18 x 10^-2	1.81
Isoproturon	3.902	3.902	3.902	1.05	2.06 x 10^-2	1.86
Triadimenol	5.063	5.063	5.063	1.66	0.220	2.40
Linuron	5.126	5.126	5.126	1.69	0.228	2.59
Naphthalene	4.529	4.529	4.529	1.38	0.139	2.75
Endosulfan-diol	5.982	5.977	5.979	2.14	0.330	3.02
Fenthion	7.449	7.449	7.449	2.91	0.464	3.31
α-Endosulfan	10.272	10.272	10.272	4.39	0.643	4.09
Diclofop-methyl	11.259	11.254	11.256	4.91	0.691	4.20
Phenanthrene	8.173	8.173	8.173	3.29	0.517	4.09
DDT	20.865	20.865	20.865	9.95	0.998	5.63

Validity criteria fulfilled:

yes

Conclusions:

The adsorption coefficient of the test item was determined to be m the range 42.8 to > 4.27 x 10E05 with a Log10 Pow of 1.63 to > 5.63.

Executive summary:

GUIDELINE

The determination was carried out using the HPLC screening method, designed to be compatible with Method C.19 Adsorption Coefficient 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 test utilised a High Performance Liquid Chromatograph. A commercially available cyanopropyl reverse phase HPLC column containing lipophilic and polar moieties was used.

 

RESULTS

The adsorption coefficient of the test item was determined to be in the range 42.8 to > 4.27 x 10E05 with a Log10 Pow of 1.63 to > 5.63.

Description of key information

The adsorption coefficient of the test item was determined to be in the range 42.8 to > 4.27 x 10E05 with a Log10 Pow of 1.63 to > 5.63 (OECD 121 and EU Method C.19).

Additional information

GUIDELINE

The determination was carried out using the HPLC screening method, designed to be compatible with Method C.19 Adsorption Coefficient 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 test utilised a High Performance Liquid Chromatograph. A commercially available cyanopropyl reverse phase HPLC column containing lipophilic and polar moieties was used.

 

RESULTS

The adsorption coefficient of the test item was determined to be in the range 42.8 to > 4.27 x 10E05 with a Log10 Pow of 1.63 to > 5.63.