Phosphoric acid, mono- and di-C16-18 (even numbered) alkyl esters, salts with 2,2'-iminodiethanol

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

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

Remarks:

See the Justification of Read Across

Adequacy of study:

key study

Study period:

2018

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

See the Read Across justification document

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

read-across source

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:

equivalent or similar 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:

other:

Specific details on test material used for the study:

Name: Phosphoric acid, mixed decyl and octyl esters, compds. with diethanolamine
CAS No.: 68425-57-0
Physical state: white solid at 20 °C (turbid, non-pourable paste)
Batch No.: PU61810016
Re-certification date of batch: 16 June 2018
Purity: 100 % (UVCB)
Moisture, % (KF) 1,2
pH, 10% in dW 7,2
Stability: stable under test conditions
Storage condition of test material: Room temperature, protected from light

Radiolabelling:

no

Details on study design: HPLC method:

The aim of this study was the determination of the adsorption coefficient of the test item on soil and on sewage sludge (Koc) by high performance liquid chromatography (HPLC) method according to EC method C.19 (440/2008) and OECD guideline 121. The analysis was performed on an analytical column packed with a commercially available cyanopropyl solid phase containing lipophilic and polar moieties. A moderately polar stationary phase based on a silica matrix was used (EC 150/4.6 Nucleodur 100-5 CN-RP 150 x 4.6 mm; 5 µm). A mixture of 55 % methanol / 45 % ultra-pure water was used as mobile phase and the column temperature was 25 °C ± 1 °C.

The dead time t0 was measured by using the unretained compound sodium nitrate. Sodium nitrate was included in the used reference mix. 6 reference compounds were used by injection of a reference mix. The reference mix was injected two times before and two times after the test item sample. The retention times were determined. The retention time of the test item was determined 4 times.Two measurements (made under identical conditions and using the same set of reference items) were performed.

Analytical monitoring:

yes

Matrix no.:

#1

Matrix type:

other: EC 150/4.6 Nucleodur 100-5 CN-RP 150 x 4.6 mm; 5 µm

Key result

Sample No.:

#1

Type:

log Koc

Remarks:

mean of two runs

Value:

< 1.32 dimensionless

Temp.:

25 °C

Matrix:

column: EC 150/4.6 Nucleodur 100-5 CN-RP 150 x 4.6 mm; 5 µm

Remarks on result:

other: log Koc is below determination limit of the method (log Koc = 1.5 according to OECD 121 and EC method C.19) but within the calibration range (log Koc of the lowest reference standard phenol is 1.32.

Transformation products:

not measured

Validity criteria fulfilled:

yes

Remarks:

The log Koc of two measurements made under identical conditions and using the same set of reference items fall within a range of ± 0.25 log units. The requirements of OECD guideline 121 concerning the quality criteria are fulfilled.

Conclusions:

The log Koc of the test item is below determination limit of the method (log Koc = 1.5 according to OECD 121 and EC method C.19) but within the calibration range (log Koc of the lowest reference standard phenol is 1.32. The log Koc of the peak end was determined to be 1.82.

Executive summary:

The aim of this study was the determination of the adsorption coefficient of the test item on soil and on sewage sludge (Koc) by high performance liquid chromatography (HPLC) method according to EC method C.19 (440/2008) and OECD guideline 121. The log Koc is below determination limit of the method (log Koc = 1.5 according to OECD 121 and EC method C.19) but within the calibration range (log Koc of the lowest reference standard phenol is 1.32. The log Koc of the peak end was determined to be 1.82.

Description of key information

The log Koc of the peak end was determined to be 1.82.

 

Key value for chemical safety assessment

Koc at 20 °C:

1.82

Additional information

The adsorption/desorption was evaluated with a results of a OECD Guideline 121 (Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge and EU Method C.19 (Estimation of the Adsorption Coefficient (KOC) on Soil and Sewage Sludge Using HPLC, of a similar substance. See the justification of Read Across.

The log Koc of the peak end was determined to be 1.82.