Amines, polyethylenepoly-

Adsorption / desorption

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

adsorption / desorption, other

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Remarks:

Summary of available data used for the endpoint assessment of the target substance

Adequacy of study:

key study

Justification for type of information:

Please refer to the read-across justification attached to IUCLID section 13

Reason / purpose for cross-reference:

read-across source

Type:

log Koc

Value:

> 3.5 dimensionless

Temp.:

35 °C

Executive summary:

Experimental data on the adsorption/desorption of the substance are not available. In accordance with Regulation (EC) No 1907/2006 Annex XI, 1.5. , the assessment is therefore based on the structurally analogue substance PEHA (CAS 4067-16-7).

The adsorption /desorption of PEHA was investigated in a study according to OECD guideline 121 by HPLC estimation method. Based on the retention time of the substance a log Koc>3.5 was estimated.

Based on the experimental result for the read across substance, PEPA is considered to be acsorptive to organic matter and sediment particles.

Reference 2

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

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

Radiolabelling:

no

Details on study design: HPLC method:

EQUIPMENT/MOBILE PHASES
Instrument: Acquity UPLC system (Waters, Milford, MA, USA)
Detector: Acquity UPLC TUV detector (Waters) and ZQ 2000 mass spectrometer (Waters)
Column*: Hypersil BDS-CN, 100 mm  2.1 mm i.d., dp = 3 µm (Thermo Fisher Scientific, Waltham, MA, USA)
Column temperature: 35°C
Mobile phase: 0.1% formic acid in 55/45 (v/v) methanol/water
Flow: 0.2 ml/min
Injection volume: 10 µl
UV detection: 210 nm
MS detection:
- Ionisation source: ESI+
- Cone voltage: 28 V
- Acquisition: Full scan m/z 50 - 250 amu; MRM m/z 233 amu (test substance); MRM m/z 147 amu (structural homologue)

* Analyses were also performed without column in the analytical system (autosampler was connected to the detectors via a by-pass).

REFERENCE SUBSTANCES
2,4-DDT (97.2%, Supelco, Bellefonte, PA, USA);
TETA, structural homologue of the test substance:
- Name: Triethylenetetramine (TETA)
- Molecular formula: C6H18N4
- Molecular weight: 146.23
- Substance type: Clear colourless liquid
- Physical state: liquid
- Analytical purity: 96.2%
- Lot/batch No.: P0632
- Expiration date of the lot/batch: 14 August 2010
- Stability under test conditions: Stable
- Storage condition of test material: At room temperature in the dark under nitrogen

Log Koc structural homologue: 3.5
Log Koc 2,4-DDT: 5.63

DETERMINATION OF RETENTION TIMES
Reference substance solution: A 1.05 g/l stock solution of 2,4-DDT in methanol was used. The stock solution was diluted to obtain an end solution of 0.1% formic acid in 55/45 (v/v) methanol/water.
Structural homologue solution: A 1148 mg/l stock solution of the structural homologue was prepared in water. The stock solution was diluted with 0.1% formic acid in 55/45 (v/v) methanol/water. The final concentration of the structural homologue solution was 100 mg/l.
Test substance solution: A 1188 mg/l stock solution of the test substance was prepared in water. The stock solution was diluted with 0.1% formic acid in 55/45 (v/v) methanol/water. The final concentration of the test substance solution was 100 mg/l.

REPETITIONS
- Number of determinations: 2

EVALUATION
Retention time of the test substance was compared with the retention time of its structural homologue.

Type:

log Koc

Value:

> 3.5 dimensionless

Temp.:

35 °C

Details on results (HPLC method):

The retention time of 2,4-DDT (log Koc = 5.63) was 5.1 minutes.

In the chromatogram of the first injection of the structural homologue no peak could be detected. Based upon its log Koc value of 3.5 (Koc = 3162) the substance was expected to elute before 2,4-DDT. In the chromatogram of the second injection and of the first injection of the corresponding blank, broad peaks were detected which were due to the previous injections. This indicates that the structural homologue eluted from the column with a retention time of approximately 19 minutes.

In the chromatograms of the test substance solution, no peaks were detected. In the chromatograms of the blank solutions injected immediately after the test substance solutions, no test substance peak could be detected either.

To demonstrate that the test substance was applied, the solutions were also analysed in the by-pass mode (i.e. without the analytical column).The structural homologue and the test substance eluted in a similar way through the analytical system (peak maximum at a retention time of 1.1 minutes), whereas 2,4-DDT eluted unretained (peak maximum at 0.2 minutes). Based on this information, the Koc of the test substance should be compared with the Koc of the structural homologue, and not with 2,4-DDT.

Because the test substance was not eluted from the column within 60 minutes after the first injection, it can be safely concluded that the log Koc of the test substance is higher than the log Koc of the structural homologue.

Validity criteria fulfilled:

yes

Conclusions:

The log Koc value of the substance was determined to be > 3.5.

Description of key information

The substance is considered to be adsorptive (log Koc >3.5); read across

Key value for chemical safety assessment

Koc at 20 °C:

3 162

Additional information

Experimental data on the adsorption/desorption of the substance are not available. In accordance with Regulation (EC) No 1907/2006 Annex XI, 1.5. , the assessment is therefore based on the structurally analogue substance Penta ethylene hexamine (PEHA , CAS 4067-16-7).

The adsorption /desorption of PEHA was investigated in a study according to OECD guideline 121 by HPLC estimation method. Based on the retention time of the substance a log Koc>3.5 was estimated.

Based on the experimental result for the read across substance, PEPA is considered to be adsorptive to organic matter and sediment particles.

[LogKoc: 3.5]