2-Pentanone, 2,2',2''-[O,O',O''-(ethenylsilylidyne)trioxime]

Adsorption / desorption

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

adsorption / desorption: screening

Data waiving:

study technically not feasible

Justification for data waiving:

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
In accordance with Section 2 of REACH Annex XI, testing was omitted because it is technically not possible to conduct the study. OECD 121 and EC C.19 based on HPLC analysis are not applicable for determination of the adsorption coefficient due to the quick hydrolysis of the test substance (half-life time < 4 minutes). OECD 106 with a soil/water system is not applicable either because of the same reason. Calculation of the adsorption coefficient using a QSAR cannot be performed either since the partition coefficient cannot be determined.

Reason / purpose for cross-reference:

data waiving: supporting information

Reference 2

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Conducted with the hydrolysis product MPKO.

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:

not specified

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:

not specified

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Media:

soil/sewage sludge

Test temperature:

35 +- 1°C

Details on study design: HPLC method:

Instrument: Alliance Separation Module 2695 (Waters, Milford, MA, USA) Detector: Dual lambda Absorbance Detector 2487 (Waters) Column: 150 mm x 4.6 mm id. Hypersil BDS-CN; dp = 5 microm (Thermo, San Jose, CA?, USA) Column temperature: 35 +- 1 °C Mobile phase neutral pH: 30/70 (v/v) methanol/water Flow: 1 ml/min Injection volume: 10 microL UV detection: 210 nm

Analytical monitoring:

yes

Key result

Type:

Koc

Value:

< 20.9

Temp.:

35 °C

Key result

Type:

log Koc

Value:

< 1.32

Temp.:

35 °C

Details on results (HPLC method):

In the chromatogram of the test solution, one test substance peak was observed at a retention time of 2.6 minutes. Under the same analytical conditions, the retention time of phenol (log Koc = 1.32) was 3.1 minutes. Hence, it was concluded that the log Koc of the test substance was < 1.32 (Koc < 20.9).

pKa value for an acidic group in the molecular structure of the test substance was calculated using the Perrin calculation method:

RRC=NOH, pKa 12,49.

Validity criteria fulfilled:

yes

Conclusions:

The Koc and log Koc value of MPKO at neutral pH were determined to be <20.9 and <1.32 respectively.

Executive summary:

The adsorption coefficient (log Koc) of MPKO was determined by means of HPLC in accordance with OECD Guideline 121 and EU Method C19. In the chromatogram of the test solution, one test substance peak was observed at a retention time of 2.6 minutes. Under the same analytical conditions, the retention time of phenol (log Koc = 1.32) was 3.1 minutes. Hence, it was concluded that the log Koc of the test substance was < 1.32 (Koc < 20.9). The Koc and log Koc value of MPKO at neutral pH were determined to be < 20.9 and <1.32 respectively.

Description of key information

OS2600 shows quick hydrolysis in aqueous solutions. Therefore, the adsorption coefficient cannot be determined. However, the log Koc was determined for MPKO, the hydrolysis product of OS2600. It was determined to be < 1.32.

Key value for chemical safety assessment

Koc at 20 °C:

20.9

Additional information

Data waiving (study not technically feasible): In accordance with Section 2 of REACH Annex XI, testing was omitted because it is technically not possible to conduct the study. OECD 121 and EC C.19 based on HPLC analysis are not applicable for determination of the adsorption coefficient due to the quick hydrolysis of the test substance (half-life time < 4 minutes). OECD 106 with a soil/water system is not applicable either because of the same reason. Calculation of the adsorption coefficient using a QSAR cannot be performed either since the partition coefficient cannot be determined.

Supporting study: The adsorption coefficient (log Koc) of MPKO was determined by means of HPLC in accordance with OECD Guideline 121 and EU Method C19 (GLP study). The Koc and log Koc value of the test substance at neutral pH were determined to be < 20.9 and <1.32 respectively.

[LogKoc: 1.32]